/**
* Select and use failsafe control
* @param [in] reset_controller True if previously another controller was used
*/
int32_t failsafe_control_select(bool reset_controller)
{
if (reset_controller) {
FlightStatusArmedOptions armed;
FlightStatusArmedGet(&armed);
armed_when_enabled = (armed == FLIGHTSTATUS_ARMED_ARMED);
}
uint8_t flight_status;
FlightStatusFlightModeGet(&flight_status);
if (flight_status != FLIGHTSTATUS_FLIGHTMODE_STABILIZED1 || reset_controller) {
flight_status = FLIGHTSTATUS_FLIGHTMODE_STABILIZED1;
FlightStatusFlightModeSet(&flight_status);
}
#ifdef GIMBAL
// Gimbals do not need failsafe
StabilizationDesiredData stabilization_desired;
StabilizationDesiredGet(&stabilization_desired);
stabilization_desired.Throttle = -1;
stabilization_desired.Roll = 0;
stabilization_desired.Pitch = 0;
stabilization_desired.Yaw = 0;
stabilization_desired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_ROLL] = STABILIZATIONDESIRED_STABILIZATIONMODE_POI;
stabilization_desired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_PITCH] = STABILIZATIONDESIRED_STABILIZATIONMODE_POI;
stabilization_desired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_YAW] = STABILIZATIONDESIRED_STABILIZATIONMODE_AXISLOCK;
StabilizationDesiredSet(&stabilization_desired);
#else
// Pick default values that will roughly cause a plane to circle down
// and a quad to fall straight down
StabilizationDesiredData stabilization_desired;
StabilizationDesiredGet(&stabilization_desired);
if (!armed_when_enabled) {
/* disable stabilization so outputs do not move when system was not armed */
stabilization_desired.Throttle = -1;
stabilization_desired.Roll = 0;
stabilization_desired.Pitch = 0;
stabilization_desired.Yaw = 0;
stabilization_desired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_ROLL] = STABILIZATIONDESIRED_STABILIZATIONMODE_NONE;
stabilization_desired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_PITCH] = STABILIZATIONDESIRED_STABILIZATIONMODE_NONE;
stabilization_desired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_YAW] = STABILIZATIONDESIRED_STABILIZATIONMODE_NONE;
} else {
/* Pick default values that will roughly cause a plane to circle down and */
/* a quad to fall straight down */
stabilization_desired.Throttle = -1;
stabilization_desired.Roll = -10;
stabilization_desired.Pitch = 0;
stabilization_desired.Yaw = -5;
stabilization_desired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_ROLL] = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabilization_desired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_PITCH] = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabilization_desired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_YAW] = STABILIZATIONDESIRED_STABILIZATIONMODE_RATE;
}
StabilizationDesiredSet(&stabilization_desired);
#endif
return 0;
}
void VtolLandFSM::run_at_descentrate(uint8_t flTimeout)
{
VelocityStateData velocityState;
VelocityStateGet(&velocityState);
StabilizationDesiredData stabDesired;
StabilizationDesiredGet(&stabDesired);
mLandData->sum1 += velocityState.Down;
mLandData->sum2 += stabDesired.Thrust;
mLandData->observationCount++;
if (flTimeout) {
mLandData->fsmLandStatus.averageDescentRate = boundf((mLandData->sum1 / (float)(mLandData->observationCount)), 0.5f * MIN_LANDRATE, 1.5f * MAX_LANDRATE);
mLandData->fsmLandStatus.averageDescentThrust = boundf((mLandData->sum2 / (float)(mLandData->observationCount)), vtolPathFollowerSettings->ThrustLimits.Min, vtolPathFollowerSettings->ThrustLimits.Max);
// We need to calculate a neutral limit to use later to constrain upper thrust range during states where we are close to the ground
// As our battery gets flat, ThrustLimits.Neutral needs to constrain us too much and we get too fast a descent rate. We can
// detect this by the fact that the descent rate will exceed the target and the required thrust will exceed the neutral value
mLandData->fsmLandStatus.calculatedNeutralThrust = mLandData->fsmLandStatus.averageDescentRate / mLandData->fsmLandStatus.targetDescentRate * mLandData->fsmLandStatus.averageDescentThrust;
mLandData->fsmLandStatus.calculatedNeutralThrust = boundf(mLandData->fsmLandStatus.calculatedNeutralThrust, vtolPathFollowerSettings->ThrustLimits.Neutral, vtolPathFollowerSettings->ThrustLimits.Max);
setState(LAND_STATE_WTG_FOR_GROUNDEFFECT, STATUSVTOLLAND_STATEEXITREASON_DESCENTRATEOK);
}
}
void VtolLandFSM::run_wtg_for_descentrate(uint8_t flTimeout)
{
// Look at current actual thrust...are we already shutdown??
VelocityStateData velocityState;
VelocityStateGet(&velocityState);
StabilizationDesiredData stabDesired;
StabilizationDesiredGet(&stabDesired);
// We don't expect PID to get exactly the target descent rate, so have a lower
// water mark but need to see 5 observations to be confident that we have semi-stable
// descent achieved
// we need to see velocity down within a range of control before we proceed, without which we
// really don't have confidence to allow later states to run.
if (velocityState.Down > (LANDRATE_LOWLIMIT_FACTOR * mLandData->fsmLandStatus.targetDescentRate) &&
velocityState.Down < (LANDRATE_HILIMIT_FACTOR * mLandData->fsmLandStatus.targetDescentRate)) {
if (mLandData->observationCount++ > WTG_FOR_DESCENTRATE_COUNT_LIMIT) {
setState(LAND_STATE_AT_DESCENTRATE, STATUSVTOLLAND_STATEEXITREASON_DESCENTRATEOK);
return;
}
}
if (flTimeout) {
setState(LAND_STATE_ABORT, STATUSVTOLLAND_STATEEXITREASON_TIMEOUT);
}
}
void plan_setup_AutoTakeoff()
{
autotakeoffState = STATUSVTOLAUTOTAKEOFF_CONTROLSTATE_WAITFORARMED;
// We only allow takeoff if the state transition of disarmed to armed occurs
// whilst in the autotake flight mode
FlightStatusData flightStatus;
FlightStatusGet(&flightStatus);
StabilizationDesiredData stabiDesired;
StabilizationDesiredGet(&stabiDesired);
// Are we inflight?
if (flightStatus.Armed && stabiDesired.Thrust > AUTOTAKEOFF_INFLIGHT_THROTTLE_CHECK_LIMIT) {
// ok assume already in flight and just enter position hold
// if we are not actually inflight this will just be a violent autotakeoff
autotakeoffState = STATUSVTOLAUTOTAKEOFF_CONTROLSTATE_POSITIONHOLD;
plan_setup_positionHold();
} else {
if (flightStatus.Armed) {
autotakeoffState = STATUSVTOLAUTOTAKEOFF_CONTROLSTATE_REQUIREUNARMEDFIRST;
// Note that if this mode was invoked unintentionally whilst in flight, effectively
// all inputs get ignored and the vtol continues to fly to its previous
// stabi command.
}
PathDesiredData pathDesired;
plan_setup_AutoTakeoff_helper(&pathDesired);
PathDesiredSet(&pathDesired);
}
}
static void UpdateStabilizationDesired(bool doingIdent) {
StabilizationDesiredData stabDesired;
StabilizationDesiredGet(&stabDesired);
uint8_t rollMax, pitchMax;
float manualRate[STABILIZATIONSETTINGS_MANUALRATE_NUMELEM];
StabilizationSettingsRollMaxGet(&rollMax);
StabilizationSettingsPitchMaxGet(&pitchMax);
StabilizationSettingsManualRateGet(manualRate);
ManualControlCommandRollGet(&stabDesired.Roll);
stabDesired.Roll *= rollMax;
ManualControlCommandPitchGet(&stabDesired.Pitch);
stabDesired.Pitch *= pitchMax;
ManualControlCommandYawGet(&stabDesired.Yaw);
stabDesired.Yaw *= manualRate[STABILIZATIONSETTINGS_MANUALRATE_YAW];
if (doingIdent) {
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_ROLL] = STABILIZATIONDESIRED_STABILIZATIONMODE_SYSTEMIDENT;
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_PITCH] = STABILIZATIONDESIRED_STABILIZATIONMODE_SYSTEMIDENT;
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_YAW] = STABILIZATIONDESIRED_STABILIZATIONMODE_SYSTEMIDENT;
} else {
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_ROLL] = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_PITCH] = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_YAW] = STABILIZATIONDESIRED_STABILIZATIONMODE_RATE;
}
ManualControlCommandThrottleGet(&stabDesired.Throttle);
StabilizationDesiredSet(&stabDesired);
}
static void updateStabilizationDesired(ManualControlCommandData * cmd, ManualControlSettingsData * settings)
{
StabilizationDesiredData stabilization;
StabilizationDesiredGet(&stabilization);
StabilizationSettingsData stabSettings;
StabilizationSettingsGet(&stabSettings);
uint8_t * stab_settings;
switch(cmd->FlightMode) {
case MANUALCONTROLCOMMAND_FLIGHTMODE_STABILIZED1:
stab_settings = settings->Stabilization1Settings;
break;
case MANUALCONTROLCOMMAND_FLIGHTMODE_STABILIZED2:
stab_settings = settings->Stabilization2Settings;
break;
case MANUALCONTROLCOMMAND_FLIGHTMODE_STABILIZED3:
stab_settings = settings->Stabilization3Settings;
break;
default:
// Major error, this should not occur because only enter this block when one of these is true
AlarmsSet(SYSTEMALARMS_ALARM_MANUALCONTROL, SYSTEMALARMS_ALARM_CRITICAL);
break;
}
// TOOD: Add assumption about order of stabilization desired and manual control stabilization mode fields having same order
stabilization.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_ROLL] = stab_settings[0];
stabilization.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_PITCH] = stab_settings[1];
stabilization.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_YAW] = stab_settings[2];
stabilization.Roll = (stab_settings[0] == STABILIZATIONDESIRED_STABILIZATIONMODE_NONE) ? cmd->Roll :
(stab_settings[0] == STABILIZATIONDESIRED_STABILIZATIONMODE_RATE) ? cmd->Roll * stabSettings.MaximumRate[STABILIZATIONSETTINGS_MAXIMUMRATE_ROLL] :
(stab_settings[0] == STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE) ? cmd->Roll * stabSettings.RollMax :
0; // this is an invalid mode
;
stabilization.Pitch = (stab_settings[1] == STABILIZATIONDESIRED_STABILIZATIONMODE_NONE) ? cmd->Pitch :
(stab_settings[1] == STABILIZATIONDESIRED_STABILIZATIONMODE_RATE) ? cmd->Pitch * stabSettings.MaximumRate[STABILIZATIONSETTINGS_MAXIMUMRATE_PITCH] :
(stab_settings[1] == STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE) ? cmd->Pitch * stabSettings.PitchMax :
0; // this is an invalid mode
stabilization.Yaw = (stab_settings[2] == STABILIZATIONDESIRED_STABILIZATIONMODE_NONE) ? cmd->Yaw :
(stab_settings[2] == STABILIZATIONDESIRED_STABILIZATIONMODE_RATE) ? cmd->Yaw * stabSettings.MaximumRate[STABILIZATIONSETTINGS_MAXIMUMRATE_YAW] :
(stab_settings[2] == STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE) ? fmod(cmd->Yaw * 180.0, 360) :
0; // this is an invalid mode
stabilization.Throttle = (cmd->Throttle < 0) ? -1 : cmd->Throttle;
StabilizationDesiredSet(&stabilization);
}
/**
* Module thread, should not return.
*/
static void AutotuneTask(void *parameters)
{
//AlarmsClear(SYSTEMALARMS_ALARM_ATTITUDE);
enum AUTOTUNE_STATE state = AT_INIT;
portTickType lastUpdateTime = xTaskGetTickCount();
while(1) {
PIOS_WDG_UpdateFlag(PIOS_WDG_AUTOTUNE);
// TODO:
// 1. get from queue
// 2. based on whether it is flightstatus or manualcontrol
portTickType diffTime;
const uint32_t PREPARE_TIME = 2000;
const uint32_t MEAURE_TIME = 30000;
FlightStatusData flightStatus;
FlightStatusGet(&flightStatus);
// Only allow this module to run when autotuning
if (flightStatus.FlightMode != FLIGHTSTATUS_FLIGHTMODE_AUTOTUNE) {
state = AT_INIT;
vTaskDelay(50);
continue;
}
StabilizationDesiredData stabDesired;
StabilizationDesiredGet(&stabDesired);
StabilizationSettingsData stabSettings;
StabilizationSettingsGet(&stabSettings);
ManualControlSettingsData manualSettings;
ManualControlSettingsGet(&manualSettings);
ManualControlCommandData manualControl;
ManualControlCommandGet(&manualControl);
RelayTuningSettingsData relaySettings;
RelayTuningSettingsGet(&relaySettings);
bool rate = relaySettings.Mode == RELAYTUNINGSETTINGS_MODE_RATE;
if (rate) { // rate mode
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_ROLL] = STABILIZATIONDESIRED_STABILIZATIONMODE_RATE;
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_PITCH] = STABILIZATIONDESIRED_STABILIZATIONMODE_RATE;
stabDesired.Roll = manualControl.Roll * stabSettings.ManualRate[STABILIZATIONSETTINGS_MANUALRATE_ROLL];
stabDesired.Pitch = manualControl.Pitch * stabSettings.ManualRate[STABILIZATIONSETTINGS_MANUALRATE_PITCH];
} else {
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_ROLL] = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_PITCH] = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabDesired.Roll = manualControl.Roll * stabSettings.RollMax;
stabDesired.Pitch = manualControl.Pitch * stabSettings.PitchMax;
}
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_YAW] = STABILIZATIONDESIRED_STABILIZATIONMODE_RATE;
stabDesired.Yaw = manualControl.Yaw * stabSettings.ManualRate[STABILIZATIONSETTINGS_MANUALRATE_YAW];
stabDesired.Throttle = manualControl.Throttle;
switch(state) {
case AT_INIT:
lastUpdateTime = xTaskGetTickCount();
// Only start when armed and flying
if (flightStatus.Armed == FLIGHTSTATUS_ARMED_ARMED && stabDesired.Throttle > 0)
state = AT_START;
break;
case AT_START:
diffTime = xTaskGetTickCount() - lastUpdateTime;
// Spend the first block of time in normal rate mode to get airborne
if (diffTime > PREPARE_TIME) {
state = AT_ROLL;
lastUpdateTime = xTaskGetTickCount();
}
break;
case AT_ROLL:
diffTime = xTaskGetTickCount() - lastUpdateTime;
// Run relay mode on the roll axis for the measurement time
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_ROLL] = rate ? STABILIZATIONDESIRED_STABILIZATIONMODE_RELAYRATE :
STABILIZATIONDESIRED_STABILIZATIONMODE_RELAYATTITUDE;
if (diffTime > MEAURE_TIME) { // Move on to next state
state = AT_PITCH;
lastUpdateTime = xTaskGetTickCount();
}
break;
case AT_PITCH:
diffTime = xTaskGetTickCount() - lastUpdateTime;
// Run relay mode on the pitch axis for the measurement time
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_PITCH] = rate ? STABILIZATIONDESIRED_STABILIZATIONMODE_RELAYRATE :
STABILIZATIONDESIRED_STABILIZATIONMODE_RELAYATTITUDE;
if (diffTime > MEAURE_TIME) { // Move on to next state
state = AT_FINISHED;
lastUpdateTime = xTaskGetTickCount();
}
break;
case AT_FINISHED:
// Wait until disarmed and landed before updating the settings
if (flightStatus.Armed == FLIGHTSTATUS_ARMED_DISARMED && stabDesired.Throttle <= 0)
state = AT_SET;
break;
case AT_SET:
update_stabilization_settings();
state = AT_INIT;
break;
default:
// Set an alarm or some shit like that
break;
}
StabilizationDesiredSet(&stabDesired);
vTaskDelay(10);
}
}
/**
* Compute desired attitude from the desired velocity
*
* Takes in @ref NedActual which has the acceleration in the
* NED frame as the feedback term and then compares the
* @ref VelocityActual against the @ref VelocityDesired
*/
static void updateGroundDesiredAttitude()
{
float dT = guidanceSettings.UpdatePeriod / 1000.0f;
VelocityDesiredData velocityDesired;
VelocityActualData velocityActual;
StabilizationDesiredData stabDesired;
AttitudeActualData attitudeActual;
NedAccelData nedAccel;
GroundPathFollowerSettingsData guidanceSettings;
StabilizationSettingsData stabSettings;
SystemSettingsData systemSettings;
SystemSettingsGet(&systemSettings);
GroundPathFollowerSettingsGet(&guidanceSettings);
VelocityActualGet(&velocityActual);
VelocityDesiredGet(&velocityDesired);
StabilizationDesiredGet(&stabDesired);
VelocityDesiredGet(&velocityDesired);
AttitudeActualGet(&attitudeActual);
StabilizationSettingsGet(&stabSettings);
NedAccelGet(&nedAccel);
float northVel = velocityActual.North;
float eastVel = velocityActual.East;
// Calculate direction from velocityDesired and set stabDesired.Yaw
stabDesired.Yaw = atan2f( velocityDesired.East, velocityDesired.North ) * RAD2DEG;
// Calculate throttle and set stabDesired.Throttle
float velDesired = sqrtf(powf(velocityDesired.East,2) + powf(velocityDesired.North,2));
float velActual = sqrtf(powf(eastVel,2) + powf(northVel,2));
ManualControlCommandData manualControlData;
ManualControlCommandGet(&manualControlData);
switch (guidanceSettings.ThrottleControl) {
case GROUNDPATHFOLLOWERSETTINGS_THROTTLECONTROL_MANUAL:
{
stabDesired.Throttle = manualControlData.Throttle;
break;
}
case GROUNDPATHFOLLOWERSETTINGS_THROTTLECONTROL_PROPORTIONAL:
{
float velRatio = velDesired / guidanceSettings.HorizontalVelMax;
stabDesired.Throttle = guidanceSettings.MaxThrottle * velRatio;
if (guidanceSettings.ManualOverride == GROUNDPATHFOLLOWERSETTINGS_MANUALOVERRIDE_TRUE) {
stabDesired.Throttle = stabDesired.Throttle * manualControlData.Throttle;
}
break;
}
case GROUNDPATHFOLLOWERSETTINGS_THROTTLECONTROL_AUTO:
{
float velError = velDesired - velActual;
stabDesired.Throttle = pid_apply(&ground_pids[VELOCITY], velError, dT) + velDesired * guidanceSettings.VelocityFeedforward;
if (guidanceSettings.ManualOverride == GROUNDPATHFOLLOWERSETTINGS_MANUALOVERRIDE_TRUE) {
stabDesired.Throttle = stabDesired.Throttle * manualControlData.Throttle;
}
break;
}
default:
{
PIOS_Assert(0);
break;
}
}
// Limit throttle as per settings
stabDesired.Throttle = bound_min_max(stabDesired.Throttle, 0, guidanceSettings.MaxThrottle);
// Set StabilizationDesired object
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_ROLL] = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_PITCH] = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_YAW] = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
StabilizationDesiredSet(&stabDesired);
}
/**
* Module thread, should not return.
*/
static void groundPathFollowerTask(void *parameters)
{
SystemSettingsData systemSettings;
FlightStatusData flightStatus;
uint32_t lastUpdateTime;
GroundPathFollowerSettingsConnectCallback(SettingsUpdatedCb);
PathDesiredConnectCallback(SettingsUpdatedCb);
GroundPathFollowerSettingsGet(&guidanceSettings);
PathDesiredGet(&pathDesired);
// Main task loop
lastUpdateTime = PIOS_Thread_Systime();
while (1) {
// Conditions when this runs:
// 1. Must have GROUND type airframe
// 2. Flight mode is PositionHold and PathDesired.Mode is Endpoint OR
// FlightMode is PathPlanner and PathDesired.Mode is Endpoint or Path
SystemSettingsGet(&systemSettings);
if ( (systemSettings.AirframeType != SYSTEMSETTINGS_AIRFRAMETYPE_GROUNDVEHICLECAR) &&
(systemSettings.AirframeType != SYSTEMSETTINGS_AIRFRAMETYPE_GROUNDVEHICLEDIFFERENTIAL) &&
(systemSettings.AirframeType != SYSTEMSETTINGS_AIRFRAMETYPE_GROUNDVEHICLEMOTORCYCLE) )
{
AlarmsSet(SYSTEMALARMS_ALARM_PATHFOLLOWER,SYSTEMALARMS_ALARM_WARNING);
PIOS_Thread_Sleep(1000);
continue;
}
// Continue collecting data if not enough time
PIOS_Thread_Sleep_Until(&lastUpdateTime, guidanceSettings.UpdatePeriod);
// Convert the accels into the NED frame
updateNedAccel();
FlightStatusGet(&flightStatus);
// Check the combinations of flightmode and pathdesired mode
switch(flightStatus.FlightMode) {
/* This combination of RETURNTOHOME and HOLDPOSITION looks strange but
* is correct. RETURNTOHOME mode uses HOLDPOSITION with the position
* set to home */
case FLIGHTSTATUS_FLIGHTMODE_RETURNTOHOME:
if (pathDesired.Mode == PATHDESIRED_MODE_HOLDPOSITION) {
updateEndpointVelocity();
updateGroundDesiredAttitude();
} else {
AlarmsSet(SYSTEMALARMS_ALARM_PATHFOLLOWER,SYSTEMALARMS_ALARM_ERROR);
}
break;
case FLIGHTSTATUS_FLIGHTMODE_POSITIONHOLD:
if (pathDesired.Mode == PATHDESIRED_MODE_HOLDPOSITION) {
updateEndpointVelocity();
updateGroundDesiredAttitude();
} else {
AlarmsSet(SYSTEMALARMS_ALARM_PATHFOLLOWER,SYSTEMALARMS_ALARM_ERROR);
}
break;
case FLIGHTSTATUS_FLIGHTMODE_PATHPLANNER:
if (pathDesired.Mode == PATHDESIRED_MODE_FLYENDPOINT ||
pathDesired.Mode == PATHDESIRED_MODE_HOLDPOSITION) {
updateEndpointVelocity();
updateGroundDesiredAttitude();
} else if (pathDesired.Mode == PATHDESIRED_MODE_FLYVECTOR ||
pathDesired.Mode == PATHDESIRED_MODE_FLYCIRCLELEFT ||
pathDesired.Mode == PATHDESIRED_MODE_FLYCIRCLERIGHT) {
updatePathVelocity();
updateGroundDesiredAttitude();
} else {
AlarmsSet(SYSTEMALARMS_ALARM_PATHFOLLOWER,SYSTEMALARMS_ALARM_ERROR);
}
break;
default:
// Be cleaner and get rid of global variables
northVelIntegral = 0;
eastVelIntegral = 0;
northPosIntegral = 0;
eastPosIntegral = 0;
// Track throttle before engaging this mode. Cheap system ident
StabilizationDesiredData stabDesired;
StabilizationDesiredGet(&stabDesired);
throttleOffset = stabDesired.Throttle;
break;
}
AlarmsClear(SYSTEMALARMS_ALARM_PATHFOLLOWER);
}
}
/**
* Module thread, should not return.
*/
static void altitudeHoldTask(void *parameters)
{
bool engaged = false;
AltitudeHoldDesiredData altitudeHoldDesired;
StabilizationDesiredData stabilizationDesired;
AltitudeHoldSettingsData altitudeHoldSettings;
UAVObjEvent ev;
struct pid velocity_pid;
// Listen for object updates.
AltitudeHoldDesiredConnectQueue(queue);
AltitudeHoldSettingsConnectQueue(queue);
FlightStatusConnectQueue(queue);
AltitudeHoldSettingsGet(&altitudeHoldSettings);
pid_configure(&velocity_pid, altitudeHoldSettings.VelocityKp,
altitudeHoldSettings.VelocityKi, 0.0f, 1.0f);
AlarmsSet(SYSTEMALARMS_ALARM_ALTITUDEHOLD, SYSTEMALARMS_ALARM_OK);
// Main task loop
const uint32_t dt_ms = 5;
const float dt_s = dt_ms * 0.001f;
uint32_t timeout = dt_ms;
while (1) {
if (PIOS_Queue_Receive(queue, &ev, timeout) != true) {
} else if (ev.obj == FlightStatusHandle()) {
uint8_t flight_mode;
FlightStatusFlightModeGet(&flight_mode);
if (flight_mode == FLIGHTSTATUS_FLIGHTMODE_ALTITUDEHOLD && !engaged) {
// Copy the current throttle as a starting point for integral
StabilizationDesiredThrottleGet(&velocity_pid.iAccumulator);
velocity_pid.iAccumulator *= 1000.0f; // pid library scales up accumulator by 1000
engaged = true;
} else if (flight_mode != FLIGHTSTATUS_FLIGHTMODE_ALTITUDEHOLD)
engaged = false;
// Run loop at 20 Hz when engaged otherwise just slowly wait for it to be engaged
timeout = engaged ? dt_ms : 100;
} else if (ev.obj == AltitudeHoldDesiredHandle()) {
AltitudeHoldDesiredGet(&altitudeHoldDesired);
} else if (ev.obj == AltitudeHoldSettingsHandle()) {
AltitudeHoldSettingsGet(&altitudeHoldSettings);
pid_configure(&velocity_pid, altitudeHoldSettings.VelocityKp,
altitudeHoldSettings.VelocityKi, 0.0f, 1.0f);
}
bool landing = altitudeHoldDesired.Land == ALTITUDEHOLDDESIRED_LAND_TRUE;
// For landing mode allow throttle to go negative to allow the integrals
// to stop winding up
const float min_throttle = landing ? -0.1f : 0.0f;
// When engaged compute altitude controller output
if (engaged) {
float position_z, velocity_z, altitude_error;
PositionActualDownGet(&position_z);
VelocityActualDownGet(&velocity_z);
position_z = -position_z; // Use positive up convention
velocity_z = -velocity_z; // Use positive up convention
// Compute the altitude error
altitude_error = altitudeHoldDesired.Altitude - position_z;
// Velocity desired is from the outer controller plus the set point
float velocity_desired = altitude_error * altitudeHoldSettings.PositionKp + altitudeHoldDesired.ClimbRate;
float throttle_desired = pid_apply_antiwindup(&velocity_pid,
velocity_desired - velocity_z,
min_throttle, 1.0f, // positive limits since this is throttle
dt_s);
if (altitudeHoldSettings.AttitudeComp > 0) {
// Throttle desired is at this point the mount desired in the up direction, we can
// account for the attitude if desired
AttitudeActualData attitudeActual;
AttitudeActualGet(&attitudeActual);
// Project a unit vector pointing up into the body frame and
// get the z component
float fraction = attitudeActual.q1 * attitudeActual.q1 -
attitudeActual.q2 * attitudeActual.q2 -
attitudeActual.q3 * attitudeActual.q3 +
attitudeActual.q4 * attitudeActual.q4;
// Add ability to scale up the amount of compensation to achieve
// level forward flight
fraction = powf(fraction, (float) altitudeHoldSettings.AttitudeComp / 100.0f);
// Dividing by the fraction remaining in the vertical projection will
// attempt to compensate for tilt. This acts like the thrust is linear
// with the output which isn't really true. If the fraction is starting
// to go negative we are inverted and should shut off throttle
throttle_desired = (fraction > 0.1f) ? (throttle_desired / fraction) : 0.0f;
}
StabilizationDesiredGet(&stabilizationDesired);
stabilizationDesired.Throttle = bound_min_max(throttle_desired, min_throttle, 1.0f);
if (landing) {
stabilizationDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_ROLL] = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabilizationDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_PITCH] = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabilizationDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_YAW] = STABILIZATIONDESIRED_STABILIZATIONMODE_AXISLOCK;
stabilizationDesired.Roll = 0;
stabilizationDesired.Pitch = 0;
stabilizationDesired.Yaw = 0;
} else {
stabilizationDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_ROLL] = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabilizationDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_PITCH] = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabilizationDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_YAW] = STABILIZATIONDESIRED_STABILIZATIONMODE_AXISLOCK;
stabilizationDesired.Roll = altitudeHoldDesired.Roll;
stabilizationDesired.Pitch = altitudeHoldDesired.Pitch;
stabilizationDesired.Yaw = altitudeHoldDesired.Yaw;
}
StabilizationDesiredSet(&stabilizationDesired);
}
}
}
/**
* @brief Handler to control Stabilized flightmodes. FlightControl is governed by "Stabilization"
* @input: ManualControlCommand
* @output: StabilizationDesired
*/
void stabilizedHandler(bool newinit)
{
if (newinit) {
StabilizationDesiredInitialize();
StabilizationBankInitialize();
}
ManualControlCommandData cmd;
ManualControlCommandGet(&cmd);
FlightModeSettingsData settings;
FlightModeSettingsGet(&settings);
StabilizationDesiredData stabilization;
StabilizationDesiredGet(&stabilization);
StabilizationBankData stabSettings;
StabilizationBankGet(&stabSettings);
cmd.Roll = applyExpo(cmd.Roll, stabSettings.StickExpo.Roll);
cmd.Pitch = applyExpo(cmd.Pitch, stabSettings.StickExpo.Pitch);
cmd.Yaw = applyExpo(cmd.Yaw, stabSettings.StickExpo.Yaw);
uint8_t *stab_settings;
FlightStatusData flightStatus;
FlightStatusGet(&flightStatus);
switch (flightStatus.FlightMode) {
case FLIGHTSTATUS_FLIGHTMODE_STABILIZED1:
stab_settings = FlightModeSettingsStabilization1SettingsToArray(settings.Stabilization1Settings);
break;
case FLIGHTSTATUS_FLIGHTMODE_STABILIZED2:
stab_settings = FlightModeSettingsStabilization2SettingsToArray(settings.Stabilization2Settings);
break;
case FLIGHTSTATUS_FLIGHTMODE_STABILIZED3:
stab_settings = FlightModeSettingsStabilization3SettingsToArray(settings.Stabilization3Settings);
break;
case FLIGHTSTATUS_FLIGHTMODE_STABILIZED4:
stab_settings = FlightModeSettingsStabilization4SettingsToArray(settings.Stabilization4Settings);
break;
case FLIGHTSTATUS_FLIGHTMODE_STABILIZED5:
stab_settings = FlightModeSettingsStabilization5SettingsToArray(settings.Stabilization5Settings);
break;
case FLIGHTSTATUS_FLIGHTMODE_STABILIZED6:
stab_settings = FlightModeSettingsStabilization6SettingsToArray(settings.Stabilization6Settings);
break;
default:
// Major error, this should not occur because only enter this block when one of these is true
AlarmsSet(SYSTEMALARMS_ALARM_MANUALCONTROL, SYSTEMALARMS_ALARM_CRITICAL);
stab_settings = FlightModeSettingsStabilization1SettingsToArray(settings.Stabilization1Settings);
return;
}
stabilization.Roll =
(stab_settings[0] == STABILIZATIONDESIRED_STABILIZATIONMODE_MANUAL) ? cmd.Roll :
(stab_settings[0] == STABILIZATIONDESIRED_STABILIZATIONMODE_RATE) ? cmd.Roll * stabSettings.ManualRate.Roll :
(stab_settings[0] == STABILIZATIONDESIRED_STABILIZATIONMODE_WEAKLEVELING) ? cmd.Roll * stabSettings.RollMax :
(stab_settings[0] == STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE) ? cmd.Roll * stabSettings.RollMax :
(stab_settings[0] == STABILIZATIONDESIRED_STABILIZATIONMODE_AXISLOCK) ? cmd.Roll * stabSettings.ManualRate.Roll :
(stab_settings[0] == STABILIZATIONDESIRED_STABILIZATIONMODE_VIRTUALBAR) ? cmd.Roll :
(stab_settings[0] == STABILIZATIONDESIRED_STABILIZATIONMODE_ACRO) ? cmd.Roll * stabSettings.ManualRate.Roll :
(stab_settings[0] == STABILIZATIONDESIRED_STABILIZATIONMODE_RATTITUDE) ? cmd.Roll * stabSettings.RollMax :
0; // this is an invalid mode
stabilization.Pitch =
(stab_settings[1] == STABILIZATIONDESIRED_STABILIZATIONMODE_MANUAL) ? cmd.Pitch :
(stab_settings[1] == STABILIZATIONDESIRED_STABILIZATIONMODE_RATE) ? cmd.Pitch * stabSettings.ManualRate.Pitch :
(stab_settings[1] == STABILIZATIONDESIRED_STABILIZATIONMODE_WEAKLEVELING) ? cmd.Pitch * stabSettings.PitchMax :
(stab_settings[1] == STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE) ? cmd.Pitch * stabSettings.PitchMax :
(stab_settings[1] == STABILIZATIONDESIRED_STABILIZATIONMODE_AXISLOCK) ? cmd.Pitch * stabSettings.ManualRate.Pitch :
(stab_settings[1] == STABILIZATIONDESIRED_STABILIZATIONMODE_VIRTUALBAR) ? cmd.Pitch :
(stab_settings[1] == STABILIZATIONDESIRED_STABILIZATIONMODE_ACRO) ? cmd.Pitch * stabSettings.ManualRate.Pitch :
(stab_settings[1] == STABILIZATIONDESIRED_STABILIZATIONMODE_RATTITUDE) ? cmd.Pitch * stabSettings.PitchMax :
0; // this is an invalid mode
// TOOD: Add assumption about order of stabilization desired and manual control stabilization mode fields having same order
stabilization.StabilizationMode.Roll = stab_settings[0];
stabilization.StabilizationMode.Pitch = stab_settings[1];
// Other axes (yaw) cannot be Rattitude, so use Rate
// Should really do this for Attitude mode as well?
if (stab_settings[2] == STABILIZATIONDESIRED_STABILIZATIONMODE_RATTITUDE) {
stabilization.StabilizationMode.Yaw = STABILIZATIONDESIRED_STABILIZATIONMODE_RATE;
stabilization.Yaw = cmd.Yaw * stabSettings.ManualRate.Yaw;
} else {
stabilization.StabilizationMode.Yaw = stab_settings[2];
stabilization.Yaw =
(stab_settings[2] == STABILIZATIONDESIRED_STABILIZATIONMODE_MANUAL) ? cmd.Yaw :
(stab_settings[2] == STABILIZATIONDESIRED_STABILIZATIONMODE_RATE) ? cmd.Yaw * stabSettings.ManualRate.Yaw :
(stab_settings[2] == STABILIZATIONDESIRED_STABILIZATIONMODE_WEAKLEVELING) ? cmd.Yaw * stabSettings.YawMax :
(stab_settings[2] == STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE) ? cmd.Yaw * stabSettings.YawMax :
(stab_settings[2] == STABILIZATIONDESIRED_STABILIZATIONMODE_AXISLOCK) ? cmd.Yaw * stabSettings.ManualRate.Yaw :
(stab_settings[2] == STABILIZATIONDESIRED_STABILIZATIONMODE_VIRTUALBAR) ? cmd.Yaw :
(stab_settings[2] == STABILIZATIONDESIRED_STABILIZATIONMODE_ACRO) ? cmd.Yaw * stabSettings.ManualRate.Yaw :
(stab_settings[2] == STABILIZATIONDESIRED_STABILIZATIONMODE_RATTITUDE) ? cmd.Yaw * stabSettings.YawMax :
0; // this is an invalid mode
}
stabilization.StabilizationMode.Thrust = stab_settings[3];
stabilization.Thrust = cmd.Thrust;
StabilizationDesiredSet(&stabilization);
}
/**
* Compute desired attitude from the desired velocity
*
* Takes in @ref NedActual which has the acceleration in the
* NED frame as the feedback term and then compares the
* @ref VelocityActual against the @ref VelocityDesired
*/
static void updateVtolDesiredAttitude()
{
float dT = guidanceSettings.UpdatePeriod / 1000.0f;
VelocityDesiredData velocityDesired;
VelocityActualData velocityActual;
StabilizationDesiredData stabDesired;
AttitudeActualData attitudeActual;
NedAccelData nedAccel;
StabilizationSettingsData stabSettings;
float northError;
float northCommand;
float eastError;
float eastCommand;
float downError;
float downCommand;
VtolPathFollowerSettingsGet(&guidanceSettings);
VelocityActualGet(&velocityActual);
VelocityDesiredGet(&velocityDesired);
StabilizationDesiredGet(&stabDesired);
VelocityDesiredGet(&velocityDesired);
AttitudeActualGet(&attitudeActual);
StabilizationSettingsGet(&stabSettings);
NedAccelGet(&nedAccel);
float northVel = velocityActual.North;
float eastVel = velocityActual.East;
float downVel = velocityActual.Down;
// Compute desired north command from velocity error
northError = velocityDesired.North - northVel;
northCommand = pid_apply_antiwindup(&vtol_pids[NORTH_VELOCITY], northError,
-guidanceSettings.MaxRollPitch, guidanceSettings.MaxRollPitch, dT) + velocityDesired.North * guidanceSettings.VelocityFeedforward;
// Compute desired east command from velocity error
eastError = velocityDesired.East - eastVel;
eastCommand = pid_apply_antiwindup(&vtol_pids[NORTH_VELOCITY], eastError,
-guidanceSettings.MaxRollPitch, guidanceSettings.MaxRollPitch, dT) + velocityDesired.East * guidanceSettings.VelocityFeedforward;
// Compute desired down command. Using NED accel as the damping term
downError = velocityDesired.Down - downVel;
// Negative is critical here since throttle is negative with down
downCommand = -pid_apply_antiwindup(&vtol_pids[DOWN_VELOCITY], downError, -1, 1, dT) +
nedAccel.Down * guidanceSettings.VerticalVelPID[VTOLPATHFOLLOWERSETTINGS_VERTICALVELPID_KD];
// If this setting is zero then the throttle level available when enabled is used for hover:wq
float used_throttle_offset = (guidanceSettings.HoverThrottle == 0) ? throttleOffset : guidanceSettings.HoverThrottle;
stabDesired.Throttle = bound_min_max(downCommand + used_throttle_offset, 0, 1);
// Project the north and east command signals into the pitch and roll based on yaw.
// For this to behave well the craft should move similarly for 5 deg roll versus 5 deg pitch.
// Notice the inputs are crudely bounded by the anti-winded but if both N and E were
// saturated and the craft were at 45 degrees that would result in a value greater than
// the limit, so apply limit again here.
stabDesired.Pitch = bound_min_max(-northCommand * cosf(attitudeActual.Yaw * DEG2RAD) +
-eastCommand * sinf(attitudeActual.Yaw * DEG2RAD),
-guidanceSettings.MaxRollPitch, guidanceSettings.MaxRollPitch);
stabDesired.Roll = bound_min_max(-northCommand * sinf(attitudeActual.Yaw * DEG2RAD) +
eastCommand * cosf(attitudeActual.Yaw * DEG2RAD),
-guidanceSettings.MaxRollPitch, guidanceSettings.MaxRollPitch);
if(guidanceSettings.ThrottleControl == VTOLPATHFOLLOWERSETTINGS_THROTTLECONTROL_FALSE) {
// For now override throttle with manual control. Disable at your risk, quad goes to China.
ManualControlCommandData manualControl;
ManualControlCommandGet(&manualControl);
stabDesired.Throttle = manualControl.Throttle;
}
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_ROLL] = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDEPLUS;
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_PITCH] = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDEPLUS;
float yaw;
switch(guidanceSettings.YawMode) {
case VTOLPATHFOLLOWERSETTINGS_YAWMODE_RATE:
/* This is awkward. This allows the transmitter to control the yaw while flying navigation */
ManualControlCommandYawGet(&yaw);
stabDesired.Yaw = stabSettings.ManualRate[STABILIZATIONSETTINGS_MANUALRATE_YAW] * yaw;
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_YAW] = STABILIZATIONDESIRED_STABILIZATIONMODE_RATE;
break;
case VTOLPATHFOLLOWERSETTINGS_YAWMODE_AXISLOCK:
ManualControlCommandYawGet(&yaw);
stabDesired.Yaw = stabSettings.ManualRate[STABILIZATIONSETTINGS_MANUALRATE_YAW] * yaw;
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_YAW] = STABILIZATIONDESIRED_STABILIZATIONMODE_AXISLOCK;
break;
case VTOLPATHFOLLOWERSETTINGS_YAWMODE_ATTITUDE:
ManualControlCommandYawGet(&yaw);
stabDesired.Yaw = stabSettings.YawMax * yaw;
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_YAW] = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
break;
case VTOLPATHFOLLOWERSETTINGS_YAWMODE_POI:
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_YAW] = STABILIZATIONDESIRED_STABILIZATIONMODE_POI;
break;
}
StabilizationDesiredSet(&stabDesired);
}
/**
* Compute desired attitude from the desired velocity for fixed wing craft
*/
uint8_t FixedWingFlyController::updateFixedDesiredAttitude()
{
uint8_t result = 1;
const float dT = fixedWingSettings->UpdatePeriod / 1000.0f;
VelocityDesiredData velocityDesired;
VelocityStateData velocityState;
StabilizationDesiredData stabDesired;
AttitudeStateData attitudeState;
FixedWingPathFollowerStatusData fixedWingPathFollowerStatus;
AirspeedStateData airspeedState;
SystemSettingsData systemSettings;
float groundspeedProjection;
float indicatedAirspeedState;
float indicatedAirspeedDesired;
float airspeedError;
float pitchCommand;
float descentspeedDesired;
float descentspeedError;
float powerCommand;
float airspeedVector[2];
float fluidMovement[2];
float courseComponent[2];
float courseError;
float courseCommand;
FixedWingPathFollowerStatusGet(&fixedWingPathFollowerStatus);
VelocityStateGet(&velocityState);
StabilizationDesiredGet(&stabDesired);
VelocityDesiredGet(&velocityDesired);
AttitudeStateGet(&attitudeState);
AirspeedStateGet(&airspeedState);
SystemSettingsGet(&systemSettings);
/**
* Compute speed error and course
*/
// missing sensors for airspeed-direction we have to assume within
// reasonable error that measured airspeed is actually the airspeed
// component in forward pointing direction
// airspeedVector is normalized
airspeedVector[0] = cos_lookup_deg(attitudeState.Yaw);
airspeedVector[1] = sin_lookup_deg(attitudeState.Yaw);
// current ground speed projected in forward direction
groundspeedProjection = velocityState.North * airspeedVector[0] + velocityState.East * airspeedVector[1];
// note that airspeedStateBias is ( calibratedAirspeed - groundspeedProjection ) at the time of measurement,
// but thanks to accelerometers, groundspeedProjection reacts faster to changes in direction
// than airspeed and gps sensors alone
indicatedAirspeedState = groundspeedProjection + indicatedAirspeedStateBias;
// fluidMovement is a vector describing the aproximate movement vector of
// the surrounding fluid in 2d space (aka wind vector)
fluidMovement[0] = velocityState.North - (indicatedAirspeedState * airspeedVector[0]);
fluidMovement[1] = velocityState.East - (indicatedAirspeedState * airspeedVector[1]);
// calculate the movement vector we need to fly to reach velocityDesired -
// taking fluidMovement into account
courseComponent[0] = velocityDesired.North - fluidMovement[0];
courseComponent[1] = velocityDesired.East - fluidMovement[1];
indicatedAirspeedDesired = boundf(sqrtf(courseComponent[0] * courseComponent[0] + courseComponent[1] * courseComponent[1]),
fixedWingSettings->HorizontalVelMin,
fixedWingSettings->HorizontalVelMax);
// if we could fly at arbitrary speeds, we'd just have to move towards the
// courseComponent vector as previously calculated and we'd be fine
// unfortunately however we are bound by min and max air speed limits, so
// we need to recalculate the correct course to meet at least the
// velocityDesired vector direction at our current speed
// this overwrites courseComponent
bool valid = correctCourse(courseComponent, (float *)&velocityDesired.North, fluidMovement, indicatedAirspeedDesired);
// Error condition: wind speed too high, we can't go where we want anymore
fixedWingPathFollowerStatus.Errors.Wind = 0;
if ((!valid) &&
fixedWingSettings->Safetymargins.Wind > 0.5f) { // alarm switched on
fixedWingPathFollowerStatus.Errors.Wind = 1;
result = 0;
}
// Airspeed error
airspeedError = indicatedAirspeedDesired - indicatedAirspeedState;
// Vertical speed error
descentspeedDesired = boundf(
velocityDesired.Down,
-fixedWingSettings->VerticalVelMax,
fixedWingSettings->VerticalVelMax);
descentspeedError = descentspeedDesired - velocityState.Down;
// Error condition: plane too slow or too fast
fixedWingPathFollowerStatus.Errors.Highspeed = 0;
fixedWingPathFollowerStatus.Errors.Lowspeed = 0;
if (indicatedAirspeedState > systemSettings.AirSpeedMax * fixedWingSettings->Safetymargins.Overspeed) {
fixedWingPathFollowerStatus.Errors.Overspeed = 1;
result = 0;
}
if (indicatedAirspeedState > fixedWingSettings->HorizontalVelMax * fixedWingSettings->Safetymargins.Highspeed) {
fixedWingPathFollowerStatus.Errors.Highspeed = 1;
result = 0;
}
if (indicatedAirspeedState < fixedWingSettings->HorizontalVelMin * fixedWingSettings->Safetymargins.Lowspeed) {
fixedWingPathFollowerStatus.Errors.Lowspeed = 1;
result = 0;
}
if (indicatedAirspeedState < systemSettings.AirSpeedMin * fixedWingSettings->Safetymargins.Stallspeed) {
fixedWingPathFollowerStatus.Errors.Stallspeed = 1;
result = 0;
}
/**
* Compute desired thrust command
*/
// Compute the cross feed from vertical speed to pitch, with saturation
float speedErrorToPowerCommandComponent = boundf(
(airspeedError / fixedWingSettings->HorizontalVelMin) * fixedWingSettings->AirspeedToPowerCrossFeed.Kp,
-fixedWingSettings->AirspeedToPowerCrossFeed.Max,
fixedWingSettings->AirspeedToPowerCrossFeed.Max
);
// Compute final thrust response
powerCommand = pid_apply(&PIDpower, -descentspeedError, dT) +
speedErrorToPowerCommandComponent;
// Output internal state to telemetry
fixedWingPathFollowerStatus.Error.Power = descentspeedError;
fixedWingPathFollowerStatus.ErrorInt.Power = PIDpower.iAccumulator;
fixedWingPathFollowerStatus.Command.Power = powerCommand;
// set thrust
stabDesired.Thrust = boundf(fixedWingSettings->ThrustLimit.Neutral + powerCommand,
fixedWingSettings->ThrustLimit.Min,
fixedWingSettings->ThrustLimit.Max);
// Error condition: plane cannot hold altitude at current speed.
fixedWingPathFollowerStatus.Errors.Lowpower = 0;
if (fixedWingSettings->ThrustLimit.Neutral + powerCommand >= fixedWingSettings->ThrustLimit.Max && // thrust at maximum
velocityState.Down > 0.0f && // we ARE going down
descentspeedDesired < 0.0f && // we WANT to go up
airspeedError > 0.0f && // we are too slow already
fixedWingSettings->Safetymargins.Lowpower > 0.5f) { // alarm switched on
fixedWingPathFollowerStatus.Errors.Lowpower = 1;
result = 0;
}
// Error condition: plane keeps climbing despite minimum thrust (opposite of above)
fixedWingPathFollowerStatus.Errors.Highpower = 0;
if (fixedWingSettings->ThrustLimit.Neutral + powerCommand <= fixedWingSettings->ThrustLimit.Min && // thrust at minimum
velocityState.Down < 0.0f && // we ARE going up
descentspeedDesired > 0.0f && // we WANT to go down
airspeedError < 0.0f && // we are too fast already
fixedWingSettings->Safetymargins.Highpower > 0.5f) { // alarm switched on
fixedWingPathFollowerStatus.Errors.Highpower = 1;
result = 0;
}
/**
* Compute desired pitch command
*/
// Compute the cross feed from vertical speed to pitch, with saturation
float verticalSpeedToPitchCommandComponent = boundf(-descentspeedError * fixedWingSettings->VerticalToPitchCrossFeed.Kp,
-fixedWingSettings->VerticalToPitchCrossFeed.Max,
fixedWingSettings->VerticalToPitchCrossFeed.Max
);
// Compute the pitch command as err*Kp + errInt*Ki + X_feed.
pitchCommand = -pid_apply(&PIDspeed, airspeedError, dT) + verticalSpeedToPitchCommandComponent;
fixedWingPathFollowerStatus.Error.Speed = airspeedError;
fixedWingPathFollowerStatus.ErrorInt.Speed = PIDspeed.iAccumulator;
fixedWingPathFollowerStatus.Command.Speed = pitchCommand;
stabDesired.Pitch = boundf(fixedWingSettings->PitchLimit.Neutral + pitchCommand,
fixedWingSettings->PitchLimit.Min,
fixedWingSettings->PitchLimit.Max);
// Error condition: high speed dive
fixedWingPathFollowerStatus.Errors.Pitchcontrol = 0;
if (fixedWingSettings->PitchLimit.Neutral + pitchCommand >= fixedWingSettings->PitchLimit.Max && // pitch demand is full up
velocityState.Down > 0.0f && // we ARE going down
descentspeedDesired < 0.0f && // we WANT to go up
airspeedError < 0.0f && // we are too fast already
fixedWingSettings->Safetymargins.Pitchcontrol > 0.5f) { // alarm switched on
fixedWingPathFollowerStatus.Errors.Pitchcontrol = 1;
result = 0;
}
/**
* Compute desired roll command
*/
courseError = RAD2DEG(atan2f(courseComponent[1], courseComponent[0])) - attitudeState.Yaw;
if (courseError < -180.0f) {
courseError += 360.0f;
}
if (courseError > 180.0f) {
courseError -= 360.0f;
}
// overlap calculation. Theres a dead zone behind the craft where the
// counter-yawing of some craft while rolling could render a desired right
// turn into a desired left turn. Making the turn direction based on
// current roll angle keeps the plane committed to a direction once chosen
if (courseError < -180.0f + (fixedWingSettings->ReverseCourseOverlap * 0.5f)
&& attitudeState.Roll > 0.0f) {
courseError += 360.0f;
}
if (courseError > 180.0f - (fixedWingSettings->ReverseCourseOverlap * 0.5f)
&& attitudeState.Roll < 0.0f) {
courseError -= 360.0f;
}
courseCommand = pid_apply(&PIDcourse, courseError, dT);
fixedWingPathFollowerStatus.Error.Course = courseError;
fixedWingPathFollowerStatus.ErrorInt.Course = PIDcourse.iAccumulator;
fixedWingPathFollowerStatus.Command.Course = courseCommand;
stabDesired.Roll = boundf(fixedWingSettings->RollLimit.Neutral +
courseCommand,
fixedWingSettings->RollLimit.Min,
fixedWingSettings->RollLimit.Max);
// TODO: find a check to determine loss of directional control. Likely needs some check of derivative
/**
* Compute desired yaw command
*/
// TODO implement raw control mode for yaw and base on Accels.Y
stabDesired.Yaw = 0.0f;
stabDesired.StabilizationMode.Roll = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabDesired.StabilizationMode.Pitch = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabDesired.StabilizationMode.Yaw = STABILIZATIONDESIRED_STABILIZATIONMODE_MANUAL;
stabDesired.StabilizationMode.Thrust = STABILIZATIONDESIRED_STABILIZATIONMODE_MANUAL;
StabilizationDesiredSet(&stabDesired);
FixedWingPathFollowerStatusSet(&fixedWingPathFollowerStatus);
return result;
}
/**
* Compute desired attitude from the desired velocity
*
* Takes in @ref NedActual which has the acceleration in the
* NED frame as the feedback term and then compares the
* @ref VelocityActual against the @ref VelocityDesired
*/
uint8_t waypointFollowing(uint8_t flightMode, FixedWingPathFollowerSettingsCCData fixedwingpathfollowerSettings)
{
float dT = fixedwingpathfollowerSettings.UpdatePeriod / 1000.0f; //Convert from [ms] to [s]
VelocityActualData velocityActual;
StabilizationDesiredData stabDesired;
float trueAirspeed;
float calibratedAirspeedActual;
float airspeedDesired;
float airspeedError;
float pitchCommand;
float powerCommand;
float headingError_R;
float rollCommand;
//TODO: Move these out of the loop
FixedWingAirspeedsData fixedwingAirspeeds;
FixedWingAirspeedsGet(&fixedwingAirspeeds);
VelocityActualGet(&velocityActual);
StabilizationDesiredGet(&stabDesired);
// TODO: Create UAVO that merges airspeed together
AirspeedActualTrueAirspeedGet(&trueAirspeed);
PositionActualData positionActual;
PositionActualGet(&positionActual);
PathDesiredData pathDesired;
PathDesiredGet(&pathDesired);
if (flightStatusUpdate) {
//Reset integrals
integral->totalEnergyError = 0;
integral->airspeedError = 0;
integral->lineError = 0;
integral->circleError = 0;
if (flightMode == FLIGHTSTATUS_FLIGHTMODE_RETURNTOHOME) {
// Simple Return To Home mode: climb 10 meters and fly to home position
pathDesired.Start[PATHDESIRED_START_NORTH] =
positionActual.North;
pathDesired.Start[PATHDESIRED_START_EAST] =
positionActual.East;
pathDesired.Start[PATHDESIRED_START_DOWN] =
positionActual.Down;
pathDesired.End[PATHDESIRED_END_NORTH] = 0;
pathDesired.End[PATHDESIRED_END_EAST] = 0;
pathDesired.End[PATHDESIRED_END_DOWN] =
positionActual.Down - 10;
pathDesired.StartingVelocity =
fixedwingAirspeeds.BestClimbRateSpeed;
pathDesired.EndingVelocity =
fixedwingAirspeeds.BestClimbRateSpeed;
pathDesired.Mode = PATHDESIRED_MODE_FLYVECTOR;
homeOrbit = false;
} else if (flightMode == FLIGHTSTATUS_FLIGHTMODE_POSITIONHOLD) {
// Simple position hold: stay at present altitude and position
//Offset by one so that the start and end points don't perfectly coincide
pathDesired.Start[PATHDESIRED_START_NORTH] =
positionActual.North - 1;
pathDesired.Start[PATHDESIRED_START_EAST] =
positionActual.East;
pathDesired.Start[PATHDESIRED_START_DOWN] =
positionActual.Down;
pathDesired.End[PATHDESIRED_END_NORTH] =
positionActual.North;
pathDesired.End[PATHDESIRED_END_EAST] =
positionActual.East;
pathDesired.End[PATHDESIRED_END_DOWN] =
positionActual.Down;
pathDesired.StartingVelocity =
fixedwingAirspeeds.BestClimbRateSpeed;
pathDesired.EndingVelocity =
fixedwingAirspeeds.BestClimbRateSpeed;
pathDesired.Mode = PATHDESIRED_MODE_FLYVECTOR;
}
PathDesiredSet(&pathDesired);
flightStatusUpdate = false;
}
/**
* Compute speed error (required for throttle and pitch)
*/
// Current airspeed
calibratedAirspeedActual = trueAirspeed; //BOOOOOOOOOO!!! Where's the conversion from TAS to CAS?
// Current heading
float headingActual_R =
atan2f(velocityActual.East, velocityActual.North);
// Desired airspeed
airspeedDesired = pathDesired.EndingVelocity;
// Airspeed error
airspeedError = airspeedDesired - calibratedAirspeedActual;
/**
* Compute desired throttle command
*/
//Proxy because instead of m*(1/2*v^2+g*h), it's v^2+2*gh. This saves processing power
float totalEnergyProxySetpoint = powf(pathDesired.EndingVelocity,
2.0f) -
2.0f * GRAVITY * pathDesired.End[2];
float totalEnergyProxyActual =
powf(trueAirspeed, 2.0f) - 2.0f * GRAVITY * positionActual.Down;
float errorTotalEnergy =
totalEnergyProxySetpoint - totalEnergyProxyActual;
float throttle_kp =
fixedwingpathfollowerSettings.
ThrottlePI[FIXEDWINGPATHFOLLOWERSETTINGSCC_THROTTLEPI_KP];
float throttle_ki = fixedwingpathfollowerSettings.ThrottlePI[FIXEDWINGPATHFOLLOWERSETTINGSCC_THROTTLEPI_KI];
float throttle_ilimit = fixedwingpathfollowerSettings.ThrottlePI[FIXEDWINGPATHFOLLOWERSETTINGSCC_THROTTLEPI_ILIMIT];
//Integrate with bound. Make integral leaky for better performance. Approximately 30s time constant.
if (throttle_ilimit > 0.0f) {
integral->totalEnergyError =
bound(integral->totalEnergyError + errorTotalEnergy * dT,
-throttle_ilimit / throttle_ki,
throttle_ilimit / throttle_ki) * (1.0f -
1.0f / (1.0f +
30.0f /
dT));
}
powerCommand = errorTotalEnergy * throttle_kp
+ integral->totalEnergyError * throttle_ki;
float throttlelimit_neutral =
fixedwingpathfollowerSettings.
ThrottleLimit[FIXEDWINGPATHFOLLOWERSETTINGSCC_THROTTLELIMIT_NEUTRAL];
float throttlelimit_min =
fixedwingpathfollowerSettings.
ThrottleLimit[FIXEDWINGPATHFOLLOWERSETTINGSCC_THROTTLELIMIT_MIN];
float throttlelimit_max =
fixedwingpathfollowerSettings.
ThrottleLimit[FIXEDWINGPATHFOLLOWERSETTINGSCC_THROTTLELIMIT_MAX];
// set throttle
stabDesired.Throttle = bound(powerCommand + throttlelimit_neutral,
throttlelimit_min, throttlelimit_max);
/**
* Compute desired pitch command
*/
float airspeed_kp =
fixedwingpathfollowerSettings.
AirspeedPI[FIXEDWINGPATHFOLLOWERSETTINGSCC_AIRSPEEDPI_KP];
float airspeed_ki =
fixedwingpathfollowerSettings.
AirspeedPI[FIXEDWINGPATHFOLLOWERSETTINGSCC_AIRSPEEDPI_KI];
float airspeed_ilimit =
fixedwingpathfollowerSettings.
AirspeedPI[FIXEDWINGPATHFOLLOWERSETTINGSCC_AIRSPEEDPI_ILIMIT];
if (airspeed_ki > 0.0f) {
//Integrate with saturation
integral->airspeedError =
bound(integral->airspeedError + airspeedError * dT,
-airspeed_ilimit / airspeed_ki,
airspeed_ilimit / airspeed_ki);
}
//Compute the cross feed from altitude to pitch, with saturation
float pitchcrossfeed_kp =
fixedwingpathfollowerSettings.
VerticalToPitchCrossFeed
[FIXEDWINGPATHFOLLOWERSETTINGSCC_VERTICALTOPITCHCROSSFEED_KP];
float pitchcrossfeed_min =
fixedwingpathfollowerSettings.
VerticalToPitchCrossFeed
[FIXEDWINGPATHFOLLOWERSETTINGSCC_VERTICALTOPITCHCROSSFEED_MAX];
float pitchcrossfeed_max =
fixedwingpathfollowerSettings.
VerticalToPitchCrossFeed
[FIXEDWINGPATHFOLLOWERSETTINGSCC_VERTICALTOPITCHCROSSFEED_MAX];
float alitudeError = -(pathDesired.End[2] - positionActual.Down); //Negative to convert from Down to altitude
float altitudeToPitchCommandComponent =
bound(alitudeError * pitchcrossfeed_kp,
-pitchcrossfeed_min,
pitchcrossfeed_max);
//Compute the pitch command as err*Kp + errInt*Ki + X_feed.
pitchCommand = -(airspeedError * airspeed_kp
+ integral->airspeedError * airspeed_ki) +
altitudeToPitchCommandComponent;
//Saturate pitch command
float pitchlimit_neutral =
fixedwingpathfollowerSettings.
PitchLimit[FIXEDWINGPATHFOLLOWERSETTINGSCC_PITCHLIMIT_NEUTRAL];
float pitchlimit_min =
fixedwingpathfollowerSettings.
PitchLimit[FIXEDWINGPATHFOLLOWERSETTINGSCC_PITCHLIMIT_MIN];
float pitchlimit_max =
fixedwingpathfollowerSettings.
PitchLimit[FIXEDWINGPATHFOLLOWERSETTINGSCC_PITCHLIMIT_MAX];
stabDesired.Pitch = bound(pitchlimit_neutral +
pitchCommand, pitchlimit_min, pitchlimit_max);
/**
* Compute desired roll command
*/
float p[3] =
{ positionActual.North, positionActual.East, positionActual.Down };
float *c = pathDesired.End;
float *r = pathDesired.Start;
float q[3] = { pathDesired.End[0] - pathDesired.Start[0],
pathDesired.End[1] - pathDesired.Start[1],
pathDesired.End[2] - pathDesired.Start[2]
};
float k_path = fixedwingpathfollowerSettings.VectorFollowingGain / pathDesired.EndingVelocity; //Divide gain by airspeed so that the turn rate is independent of airspeed
float k_orbit = fixedwingpathfollowerSettings.OrbitFollowingGain / pathDesired.EndingVelocity; //Divide gain by airspeed so that the turn rate is independent of airspeed
float k_psi_int = fixedwingpathfollowerSettings.FollowerIntegralGain;
//========================================
//SHOULD NOT BE HARD CODED
bool direction;
float chi_inf = PI / 4.0f; //THIS NEEDS TO BE A FUNCTION OF HOW LONG OUR PATH IS.
//Saturate chi_inf. I.e., never approach the path at a steeper angle than 45 degrees
chi_inf = chi_inf < PI / 4.0f ? PI / 4.0f : chi_inf;
//========================================
float rho;
float headingCommand_R;
float pncn = p[0] - c[0];
float pece = p[1] - c[1];
float d = sqrtf(pncn * pncn + pece * pece);
//Assume that we want a 15 degree bank angle. This should yield a nice, non-agressive turn
#define ROLL_FOR_HOLDING_CIRCLE 15.0f
//Calculate radius, rho, using r*omega=v and omega = g/V_g * tan(phi)
//THIS SHOULD ONLY BE CALCULATED ONCE, INSTEAD OF EVERY TIME
rho = powf(pathDesired.EndingVelocity,
2) / (GRAVITY * tanf(fabs(ROLL_FOR_HOLDING_CIRCLE * DEG2RAD)));
typedef enum {
LINE,
ORBIT
} pathTypes_t;
pathTypes_t pathType;
//Determine if we should fly on a line or orbit path.
switch (flightMode) {
case FLIGHTSTATUS_FLIGHTMODE_RETURNTOHOME:
if (d < rho + 5.0f * pathDesired.EndingVelocity || homeOrbit == true) { //When approx five seconds from the circle, start integrating into it
pathType = ORBIT;
homeOrbit = true;
} else {
pathType = LINE;
}
break;
case FLIGHTSTATUS_FLIGHTMODE_POSITIONHOLD:
pathType = ORBIT;
break;
default:
pathType = LINE;
break;
}
//Check to see if we've gone past our destination. Since the path follower
//is simply following a vector, it has no concept of where the vector ends.
//It will simply keep following it to infinity if we don't stop it. So while
//we don't know why the commutation to the next point failed, we don't know
//we don't want the plane flying off.
if (pathType == LINE) {
//Compute the norm squared of the horizontal path length
//IT WOULD BE NICE TO ONLY DO THIS ONCE PER WAYPOINT UPDATE, INSTEAD OF
//EVERY LOOP
float pathLength2 = q[0] * q[0] + q[1] * q[1];
//Perform a quick vector math operation, |a| < a.b/|a| = |b|cos(theta),
//to test if we've gone past the waypoint. Add in a distance equal to 5s
//of flight time, for good measure to make sure we don't add jitter.
if (((p[0] - r[0]) * q[0] + (p[1] - r[1]) * q[1]) >
pathLength2 + 5.0f * pathDesired.EndingVelocity) {
//Whoops, we've really overflown our destination point, and haven't
//received any instructions. Start circling
//flightMode will reset the next time a waypoint changes, so there's
//no danger of it getting stuck in orbit mode.
flightMode = FLIGHTSTATUS_FLIGHTMODE_POSITIONHOLD;
pathType = ORBIT;
}
}
switch (pathType) {
case ORBIT:
if (pathDesired.Mode == PATHDESIRED_MODE_FLYCIRCLELEFT) {
direction = false;
} else {
//In the case where the direction is undefined, always fly in a
//clockwise fashion
direction = true;
}
headingCommand_R =
followOrbit(c, rho, direction, p, headingActual_R, k_orbit,
k_psi_int, dT);
break;
case LINE:
headingCommand_R =
followStraightLine(r, q, p, headingActual_R, chi_inf,
k_path, k_psi_int, dT);
break;
}
//Calculate heading error
headingError_R = headingCommand_R - headingActual_R;
//Wrap heading error around circle
if (headingError_R < -PI)
headingError_R += 2.0f * PI;
if (headingError_R > PI)
headingError_R -= 2.0f * PI;
//GET RID OF THE RAD2DEG. IT CAN BE FACTORED INTO HeadingPI
float rolllimit_neutral =
fixedwingpathfollowerSettings.
RollLimit[FIXEDWINGPATHFOLLOWERSETTINGSCC_ROLLLIMIT_NEUTRAL];
float rolllimit_min =
fixedwingpathfollowerSettings.
RollLimit[FIXEDWINGPATHFOLLOWERSETTINGSCC_ROLLLIMIT_MIN];
float rolllimit_max =
fixedwingpathfollowerSettings.
RollLimit[FIXEDWINGPATHFOLLOWERSETTINGSCC_ROLLLIMIT_MAX];
float headingpi_kp =
fixedwingpathfollowerSettings.
HeadingPI[FIXEDWINGPATHFOLLOWERSETTINGSCC_HEADINGPI_KP];
rollCommand = (headingError_R * headingpi_kp) * RAD2DEG;
//Turn heading
stabDesired.Roll = bound(rolllimit_neutral +
rollCommand, rolllimit_min, rolllimit_max);
#ifdef SIM_OSX
fprintf(stderr, " headingError_R: %f, rollCommand: %f\n",
headingError_R, rollCommand);
#endif
/**
* Compute desired yaw command
*/
// Coordinated flight, so we reset the desired yaw.
stabDesired.Yaw = 0;
stabDesired.
StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_ROLL] =
STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabDesired.
StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_PITCH] =
STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabDesired.
StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_YAW] =
STABILIZATIONDESIRED_STABILIZATIONMODE_NONE;
StabilizationDesiredSet(&stabDesired);
//Stuff some debug variables into PathDesired, because right now these
//fields aren't being used.
pathDesired.ModeParameters[0] = pitchCommand;
pathDesired.ModeParameters[1] = airspeedError;
pathDesired.ModeParameters[2] = integral->airspeedError;
pathDesired.ModeParameters[3] = alitudeError;
pathDesired.UID = errorTotalEnergy;
PathDesiredSet(&pathDesired);
return 0;
}
/**
* Compute desired attitude from the desired velocity
*
* Takes in @ref NedActual which has the acceleration in the
* NED frame as the feedback term and then compares the
* @ref VelocityActual against the @ref VelocityDesired
*/
static uint8_t updateFixedDesiredAttitude()
{
uint8_t result = 1;
float dT = fixedwingpathfollowerSettings.UpdatePeriod / 1000.0f; //Convert from [ms] to [s]
VelocityDesiredData velocityDesired;
VelocityActualData velocityActual;
StabilizationDesiredData stabDesired;
AttitudeActualData attitudeActual;
FixedWingPathFollowerStatusData fixedwingpathfollowerStatus;
AirspeedActualData airspeedActual;
float groundspeedActual;
float groundspeedDesired;
float indicatedAirspeedActual;
float indicatedAirspeedDesired;
float airspeedError;
float pitchCommand;
float descentspeedDesired;
float descentspeedError;
float powerError;
float powerCommand;
float bearingError;
float bearingCommand;
FixedWingPathFollowerStatusGet(&fixedwingpathfollowerStatus);
VelocityActualGet(&velocityActual);
StabilizationDesiredGet(&stabDesired);
VelocityDesiredGet(&velocityDesired);
AttitudeActualGet(&attitudeActual);
AirspeedActualGet(&airspeedActual);
/**
* Compute speed error (required for throttle and pitch)
*/
// Current ground speed
groundspeedActual = sqrtf( velocityActual.East*velocityActual.East + velocityActual.North*velocityActual.North );
// note that airspeedActualBias is ( calibratedAirspeed - groundSpeed ) at the time of measurement,
// but thanks to accelerometers, groundspeed reacts faster to changes in direction
// than airspeed and gps sensors alone
indicatedAirspeedActual = groundspeedActual + indicatedAirspeedActualBias;
// Desired ground speed
groundspeedDesired = sqrtf(velocityDesired.North*velocityDesired.North + velocityDesired.East*velocityDesired.East);
indicatedAirspeedDesired = bound_min_max( groundspeedDesired + indicatedAirspeedActualBias,
fixedWingAirspeeds.BestClimbRateSpeed,
fixedWingAirspeeds.CruiseSpeed);
// Airspeed error (positive means not enough airspeed)
airspeedError = indicatedAirspeedDesired - indicatedAirspeedActual;
// Vertical speed error
descentspeedDesired = bound_min_max (
velocityDesired.Down,
-fixedWingAirspeeds.VerticalVelMax,
fixedWingAirspeeds.VerticalVelMax);
descentspeedError = descentspeedDesired - velocityActual.Down;
// Error condition: wind speed is higher than maximum allowed speed. We are forced backwards!
fixedwingpathfollowerStatus.Errors[FIXEDWINGPATHFOLLOWERSTATUS_ERRORS_WIND] = 0;
if (groundspeedDesired - indicatedAirspeedActualBias <= 0 ) {
fixedwingpathfollowerStatus.Errors[FIXEDWINGPATHFOLLOWERSTATUS_ERRORS_WIND] = 1;
result = 0;
}
// Error condition: plane too slow or too fast
fixedwingpathfollowerStatus.Errors[FIXEDWINGPATHFOLLOWERSTATUS_ERRORS_HIGHSPEED] = 0;
fixedwingpathfollowerStatus.Errors[FIXEDWINGPATHFOLLOWERSTATUS_ERRORS_LOWSPEED] = 0;
if ( indicatedAirspeedActual > fixedWingAirspeeds.AirSpeedMax) {
fixedwingpathfollowerStatus.Errors[FIXEDWINGPATHFOLLOWERSTATUS_ERRORS_OVERSPEED] = 1;
result = 0;
}
if ( indicatedAirspeedActual > fixedWingAirspeeds.CruiseSpeed * 1.2f) {
fixedwingpathfollowerStatus.Errors[FIXEDWINGPATHFOLLOWERSTATUS_ERRORS_HIGHSPEED] = 1;
result = 0;
}
if (indicatedAirspeedActual < fixedWingAirspeeds.BestClimbRateSpeed * 0.8f && 1) { //The next three && 1 are placeholders for UAVOs representing LANDING and TAKEOFF
fixedwingpathfollowerStatus.Errors[FIXEDWINGPATHFOLLOWERSTATUS_ERRORS_LOWSPEED] = 1;
result = 0;
}
if (indicatedAirspeedActual < fixedWingAirspeeds.StallSpeedClean && 1 && 1) { //Where the && 1 represents the UAVO that will control whether the airplane is prepped for landing or not
fixedwingpathfollowerStatus.Errors[FIXEDWINGPATHFOLLOWERSTATUS_ERRORS_STALLSPEED] = 1;
result = 0;
}
if (indicatedAirspeedActual < fixedWingAirspeeds.StallSpeedDirty && 1) {
fixedwingpathfollowerStatus.Errors[FIXEDWINGPATHFOLLOWERSTATUS_ERRORS_STALLSPEED] = 1;
result = 0;
}
if (indicatedAirspeedActual<1e-6f) {
// prevent division by zero, abort without controlling anything. This guidance mode is not suited for takeoff or touchdown, or handling stationary planes
// also we cannot handle planes flying backwards, lets just wait until the nose drops
fixedwingpathfollowerStatus.Errors[FIXEDWINGPATHFOLLOWERSTATUS_ERRORS_LOWSPEED] = 1;
return 0;
}
/**
* Compute desired throttle command
* positive airspeed error means not enough airspeed
* positive decent_speed_error means decending too fast
*/
// compute proportional throttle response
powerError = -descentspeedError +
bound_min_max(
(airspeedError / fixedWingAirspeeds.BestClimbRateSpeed)* fixedwingpathfollowerSettings.AirspeedToVerticalCrossFeed[FIXEDWINGPATHFOLLOWERSETTINGS_AIRSPEEDTOVERTICALCROSSFEED_KP] ,
-fixedwingpathfollowerSettings.AirspeedToVerticalCrossFeed[FIXEDWINGPATHFOLLOWERSETTINGS_AIRSPEEDTOVERTICALCROSSFEED_MAX],
fixedwingpathfollowerSettings.AirspeedToVerticalCrossFeed[FIXEDWINGPATHFOLLOWERSETTINGS_AIRSPEEDTOVERTICALCROSSFEED_MAX]
);
// compute saturated integral error throttle response. Make integral leaky for better performance. Approximately 30s time constant.
if (fixedwingpathfollowerSettings.PowerPI[FIXEDWINGPATHFOLLOWERSETTINGS_POWERPI_KI] >0) {
powerIntegral = bound_min_max(powerIntegral + -descentspeedError * dT,
-fixedwingpathfollowerSettings.PowerPI[FIXEDWINGPATHFOLLOWERSETTINGS_POWERPI_ILIMIT]/fixedwingpathfollowerSettings.PowerPI[FIXEDWINGPATHFOLLOWERSETTINGS_POWERPI_KI],
fixedwingpathfollowerSettings.PowerPI[FIXEDWINGPATHFOLLOWERSETTINGS_POWERPI_ILIMIT]/fixedwingpathfollowerSettings.PowerPI[FIXEDWINGPATHFOLLOWERSETTINGS_POWERPI_KI]
)*(1.0f-1.0f/(1.0f+30.0f/dT));
} else
powerIntegral = 0;
// Compute final throttle response
powerCommand = bound_min_max(
(powerError * fixedwingpathfollowerSettings.PowerPI[FIXEDWINGPATHFOLLOWERSETTINGS_POWERPI_KP] +
powerIntegral* fixedwingpathfollowerSettings.PowerPI[FIXEDWINGPATHFOLLOWERSETTINGS_POWERPI_KI]) + fixedwingpathfollowerSettings.ThrottleLimit[FIXEDWINGPATHFOLLOWERSETTINGS_THROTTLELIMIT_NEUTRAL],
fixedwingpathfollowerSettings.ThrottleLimit[FIXEDWINGPATHFOLLOWERSETTINGS_THROTTLELIMIT_MIN],
fixedwingpathfollowerSettings.ThrottleLimit[FIXEDWINGPATHFOLLOWERSETTINGS_THROTTLELIMIT_MAX]);
//Output internal state to telemetry
fixedwingpathfollowerStatus.Error[FIXEDWINGPATHFOLLOWERSTATUS_ERROR_POWER] = powerError;
fixedwingpathfollowerStatus.ErrorInt[FIXEDWINGPATHFOLLOWERSTATUS_ERRORINT_POWER] = powerIntegral;
fixedwingpathfollowerStatus.Command[FIXEDWINGPATHFOLLOWERSTATUS_COMMAND_POWER] = powerCommand;
// set throttle
stabDesired.Throttle = powerCommand;
// Error condition: plane cannot hold altitude at current speed.
fixedwingpathfollowerStatus.Errors[FIXEDWINGPATHFOLLOWERSTATUS_ERRORS_LOWPOWER] = 0;
if (
powerCommand == fixedwingpathfollowerSettings.ThrottleLimit[FIXEDWINGPATHFOLLOWERSETTINGS_THROTTLELIMIT_MAX] // throttle at maximum
&& velocityActual.Down > 0 // we ARE going down
&& descentspeedDesired < 0 // we WANT to go up
&& airspeedError > 0 // we are too slow already
)
{
fixedwingpathfollowerStatus.Errors[FIXEDWINGPATHFOLLOWERSTATUS_ERRORS_LOWPOWER] = 1;
result = 0;
}
// Error condition: plane keeps climbing despite minimum throttle (opposite of above)
fixedwingpathfollowerStatus.Errors[FIXEDWINGPATHFOLLOWERSTATUS_ERRORS_HIGHPOWER] = 0;
if (
powerCommand == fixedwingpathfollowerSettings.ThrottleLimit[FIXEDWINGPATHFOLLOWERSETTINGS_THROTTLELIMIT_MIN] // throttle at minimum
&& velocityActual.Down < 0 // we ARE going up
&& descentspeedDesired > 0 // we WANT to go down
&& airspeedError < 0 // we are too fast already
)
{
fixedwingpathfollowerStatus.Errors[FIXEDWINGPATHFOLLOWERSTATUS_ERRORS_HIGHPOWER] = 1;
result = 0;
}
/**
* Compute desired pitch command
*/
if (fixedwingpathfollowerSettings.SpeedPI[FIXEDWINGPATHFOLLOWERSETTINGS_SPEEDPI_KI] > 0){
//Integrate with saturation
airspeedErrorInt=bound_min_max(airspeedErrorInt + airspeedError * dT,
-fixedwingpathfollowerSettings.SpeedPI[FIXEDWINGPATHFOLLOWERSETTINGS_SPEEDPI_ILIMIT]/fixedwingpathfollowerSettings.SpeedPI[FIXEDWINGPATHFOLLOWERSETTINGS_SPEEDPI_KI],
fixedwingpathfollowerSettings.SpeedPI[FIXEDWINGPATHFOLLOWERSETTINGS_SPEEDPI_ILIMIT]/fixedwingpathfollowerSettings.SpeedPI[FIXEDWINGPATHFOLLOWERSETTINGS_SPEEDPI_KI]);
} else
airspeedErrorInt = 0;
//Compute the cross feed from vertical speed to pitch, with saturation
float verticalSpeedToPitchCommandComponent=bound_min_max (-descentspeedError * fixedwingpathfollowerSettings.VerticalToPitchCrossFeed[FIXEDWINGPATHFOLLOWERSETTINGS_VERTICALTOPITCHCROSSFEED_KP],
-fixedwingpathfollowerSettings.VerticalToPitchCrossFeed[FIXEDWINGPATHFOLLOWERSETTINGS_VERTICALTOPITCHCROSSFEED_MAX],
fixedwingpathfollowerSettings.VerticalToPitchCrossFeed[FIXEDWINGPATHFOLLOWERSETTINGS_VERTICALTOPITCHCROSSFEED_MAX]
);
//Compute the pitch command as err*Kp + errInt*Ki + X_feed.
pitchCommand= -(airspeedError*fixedwingpathfollowerSettings.SpeedPI[FIXEDWINGPATHFOLLOWERSETTINGS_SPEEDPI_KP]
+ airspeedErrorInt*fixedwingpathfollowerSettings.SpeedPI[FIXEDWINGPATHFOLLOWERSETTINGS_SPEEDPI_KI]
) + verticalSpeedToPitchCommandComponent;
fixedwingpathfollowerStatus.Error[FIXEDWINGPATHFOLLOWERSTATUS_ERROR_SPEED] = airspeedError;
fixedwingpathfollowerStatus.ErrorInt[FIXEDWINGPATHFOLLOWERSTATUS_ERRORINT_SPEED] = airspeedErrorInt;
fixedwingpathfollowerStatus.Command[FIXEDWINGPATHFOLLOWERSTATUS_COMMAND_SPEED] = pitchCommand;
stabDesired.Pitch = bound_min_max(fixedwingpathfollowerSettings.PitchLimit[FIXEDWINGPATHFOLLOWERSETTINGS_PITCHLIMIT_NEUTRAL] +
pitchCommand,
fixedwingpathfollowerSettings.PitchLimit[FIXEDWINGPATHFOLLOWERSETTINGS_PITCHLIMIT_MIN],
fixedwingpathfollowerSettings.PitchLimit[FIXEDWINGPATHFOLLOWERSETTINGS_PITCHLIMIT_MAX]);
// Error condition: high speed dive
fixedwingpathfollowerStatus.Errors[FIXEDWINGPATHFOLLOWERSTATUS_ERRORS_PITCHCONTROL] = 0;
if (
pitchCommand == fixedwingpathfollowerSettings.PitchLimit[FIXEDWINGPATHFOLLOWERSETTINGS_PITCHLIMIT_MAX] // pitch demand is full up
&& velocityActual.Down > 0 // we ARE going down
&& descentspeedDesired < 0 // we WANT to go up
&& airspeedError < 0 // we are too fast already
) {
fixedwingpathfollowerStatus.Errors[FIXEDWINGPATHFOLLOWERSTATUS_ERRORS_PITCHCONTROL] = 1;
result = 0;
}
/**
* Compute desired roll command
*/
if (groundspeedDesired> 1e-6f) {
bearingError = RAD2DEG * (atan2f(velocityDesired.East,velocityDesired.North) - atan2f(velocityActual.East,velocityActual.North));
} else {
// if we are not supposed to move, keep going wherever we are now. Don't make things worse by changing direction.
bearingError = 0;
}
if (bearingError<-180.0f) bearingError+=360.0f;
if (bearingError>180.0f) bearingError-=360.0f;
bearingIntegral = bound_min_max(bearingIntegral + bearingError * dT * fixedwingpathfollowerSettings.BearingPI[FIXEDWINGPATHFOLLOWERSETTINGS_BEARINGPI_KI],
-fixedwingpathfollowerSettings.BearingPI[FIXEDWINGPATHFOLLOWERSETTINGS_BEARINGPI_ILIMIT],
fixedwingpathfollowerSettings.BearingPI[FIXEDWINGPATHFOLLOWERSETTINGS_BEARINGPI_ILIMIT]);
bearingCommand = (bearingError * fixedwingpathfollowerSettings.BearingPI[FIXEDWINGPATHFOLLOWERSETTINGS_BEARINGPI_KP] +
bearingIntegral);
fixedwingpathfollowerStatus.Error[FIXEDWINGPATHFOLLOWERSTATUS_ERROR_BEARING] = bearingError;
fixedwingpathfollowerStatus.ErrorInt[FIXEDWINGPATHFOLLOWERSTATUS_ERRORINT_BEARING] = bearingIntegral;
fixedwingpathfollowerStatus.Command[FIXEDWINGPATHFOLLOWERSTATUS_COMMAND_BEARING] = bearingCommand;
stabDesired.Roll = bound_min_max( fixedwingpathfollowerSettings.RollLimit[FIXEDWINGPATHFOLLOWERSETTINGS_ROLLLIMIT_NEUTRAL] +
bearingCommand,
fixedwingpathfollowerSettings.RollLimit[FIXEDWINGPATHFOLLOWERSETTINGS_ROLLLIMIT_MIN],
fixedwingpathfollowerSettings.RollLimit[FIXEDWINGPATHFOLLOWERSETTINGS_ROLLLIMIT_MAX] );
// TODO: find a check to determine loss of directional control. Likely needs some check of derivative
/**
* Compute desired yaw command
*/
// TODO implement raw control mode for yaw and base on Accels.Y
stabDesired.Yaw = 0;
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_ROLL] = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_PITCH] = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_YAW] = STABILIZATIONDESIRED_STABILIZATIONMODE_NONE;
if (isnan(stabDesired.Roll) || isnan(stabDesired.Pitch) || isnan(stabDesired.Yaw) || isnan(stabDesired.Throttle)) {
northVelIntegral = 0;
eastVelIntegral = 0;
downVelIntegral = 0;
bearingIntegral = 0;
speedIntegral = 0;
accelIntegral = 0;
powerIntegral = 0;
airspeedErrorInt = 0;
result = 0;
} else {
StabilizationDesiredSet(&stabDesired);
}
FixedWingPathFollowerStatusSet(&fixedwingpathfollowerStatus);
return result;
}
/**
* Module thread, should not return.
*/
static void vtolPathFollowerTask(void *parameters)
{
SystemSettingsData systemSettings;
FlightStatusData flightStatus;
portTickType lastUpdateTime;
VtolPathFollowerSettingsConnectCallback(SettingsUpdatedCb);
PathDesiredConnectCallback(SettingsUpdatedCb);
VtolPathFollowerSettingsGet(&guidanceSettings);
PathDesiredGet(&pathDesired);
// Main task loop
lastUpdateTime = xTaskGetTickCount();
while (1) {
// Conditions when this runs:
// 1. Must have VTOL type airframe
// 2. Flight mode is PositionHold and PathDesired.Mode is Endpoint OR
// FlightMode is PathPlanner and PathDesired.Mode is Endpoint or Path
SystemSettingsGet(&systemSettings);
if ( (systemSettings.AirframeType != SYSTEMSETTINGS_AIRFRAMETYPE_VTOL) &&
(systemSettings.AirframeType != SYSTEMSETTINGS_AIRFRAMETYPE_QUADP) &&
(systemSettings.AirframeType != SYSTEMSETTINGS_AIRFRAMETYPE_QUADX) &&
(systemSettings.AirframeType != SYSTEMSETTINGS_AIRFRAMETYPE_HEXA) &&
(systemSettings.AirframeType != SYSTEMSETTINGS_AIRFRAMETYPE_HEXAX) &&
(systemSettings.AirframeType != SYSTEMSETTINGS_AIRFRAMETYPE_HEXACOAX) &&
(systemSettings.AirframeType != SYSTEMSETTINGS_AIRFRAMETYPE_OCTO) &&
(systemSettings.AirframeType != SYSTEMSETTINGS_AIRFRAMETYPE_OCTOV) &&
(systemSettings.AirframeType != SYSTEMSETTINGS_AIRFRAMETYPE_OCTOCOAXP) &&
(systemSettings.AirframeType != SYSTEMSETTINGS_AIRFRAMETYPE_OCTOCOAXX) &&
(systemSettings.AirframeType != SYSTEMSETTINGS_AIRFRAMETYPE_TRI) )
{
AlarmsSet(SYSTEMALARMS_ALARM_PATHFOLLOWER,SYSTEMALARMS_ALARM_WARNING);
vTaskDelay(1000);
continue;
}
// Continue collecting data if not enough time
vTaskDelayUntil(&lastUpdateTime, MS2TICKS(guidanceSettings.UpdatePeriod));
// Convert the accels into the NED frame
updateNedAccel();
FlightStatusGet(&flightStatus);
// Check the combinations of flightmode and pathdesired mode
switch(flightStatus.FlightMode) {
/* This combination of RETURNTOHOME and HOLDPOSITION looks strange but
* is correct. RETURNTOHOME mode uses HOLDPOSITION with the position
* set to home */
case FLIGHTSTATUS_FLIGHTMODE_RETURNTOHOME:
if (pathDesired.Mode == PATHDESIRED_MODE_HOLDPOSITION) {
updateEndpointVelocity();
updateVtolDesiredAttitude();
} else {
AlarmsSet(SYSTEMALARMS_ALARM_PATHFOLLOWER,SYSTEMALARMS_ALARM_ERROR);
}
break;
case FLIGHTSTATUS_FLIGHTMODE_POSITIONHOLD:
if (pathDesired.Mode == PATHDESIRED_MODE_HOLDPOSITION) {
updateEndpointVelocity();
updateVtolDesiredAttitude();
} else {
AlarmsSet(SYSTEMALARMS_ALARM_PATHFOLLOWER,SYSTEMALARMS_ALARM_ERROR);
}
break;
case FLIGHTSTATUS_FLIGHTMODE_PATHPLANNER:
if (pathDesired.Mode == PATHDESIRED_MODE_FLYENDPOINT ||
pathDesired.Mode == PATHDESIRED_MODE_HOLDPOSITION) {
updateEndpointVelocity();
updateVtolDesiredAttitude();
} else if (pathDesired.Mode == PATHDESIRED_MODE_FLYVECTOR ||
pathDesired.Mode == PATHDESIRED_MODE_FLYCIRCLELEFT ||
pathDesired.Mode == PATHDESIRED_MODE_FLYCIRCLERIGHT) {
updatePathVelocity();
updateVtolDesiredAttitude();
} else {
AlarmsSet(SYSTEMALARMS_ALARM_PATHFOLLOWER,SYSTEMALARMS_ALARM_ERROR);
}
break;
default:
for (uint32_t i = 0; i < VTOL_PID_NUM; i++)
pid_zero(&vtol_pids[i]);
// Track throttle before engaging this mode. Cheap system ident
StabilizationDesiredData stabDesired;
StabilizationDesiredGet(&stabDesired);
throttleOffset = stabDesired.Throttle;
break;
}
AlarmsClear(SYSTEMALARMS_ALARM_PATHFOLLOWER);
}
}
/**
* Compute desired attitude from the desired velocity
*
* Takes in @ref NedActual which has the acceleration in the
* NED frame as the feedback term and then compares the
* @ref VelocityActual against the @ref VelocityDesired
*/
static void updateVtolDesiredAttitude()
{
static portTickType lastSysTime;
portTickType thisSysTime = xTaskGetTickCount();;
float dT = 0;
VelocityDesiredData velocityDesired;
VelocityActualData velocityActual;
StabilizationDesiredData stabDesired;
AttitudeActualData attitudeActual;
NedAccelData nedAccel;
GuidanceSettingsData guidanceSettings;
StabilizationSettingsData stabSettings;
SystemSettingsData systemSettings;
float northError;
float northCommand;
float eastError;
float eastCommand;
float downError;
float downCommand;
// Check how long since last update
if(thisSysTime > lastSysTime) // reuse dt in case of wraparound
dT = (thisSysTime - lastSysTime) / portTICK_RATE_MS / 1000.0f;
lastSysTime = thisSysTime;
SystemSettingsGet(&systemSettings);
GuidanceSettingsGet(&guidanceSettings);
VelocityActualGet(&velocityActual);
VelocityDesiredGet(&velocityDesired);
StabilizationDesiredGet(&stabDesired);
VelocityDesiredGet(&velocityDesired);
AttitudeActualGet(&attitudeActual);
StabilizationSettingsGet(&stabSettings);
NedAccelGet(&nedAccel);
// Testing code - refactor into manual control command
ManualControlCommandData manualControlData;
ManualControlCommandGet(&manualControlData);
stabDesired.Yaw = stabSettings.MaximumRate[STABILIZATIONSETTINGS_MAXIMUMRATE_YAW] * manualControlData.Yaw;
// Compute desired north command
northError = velocityDesired.North - velocityActual.North;
northVelIntegral = bound(northVelIntegral + northError * dT * guidanceSettings.HorizontalVelPID[GUIDANCESETTINGS_HORIZONTALVELPID_KI],
-guidanceSettings.HorizontalVelPID[GUIDANCESETTINGS_HORIZONTALVELPID_ILIMIT],
guidanceSettings.HorizontalVelPID[GUIDANCESETTINGS_HORIZONTALVELPID_ILIMIT]);
northCommand = (northError * guidanceSettings.HorizontalVelPID[GUIDANCESETTINGS_HORIZONTALVELPID_KP] +
northVelIntegral -
nedAccel.North * guidanceSettings.HorizontalVelPID[GUIDANCESETTINGS_HORIZONTALVELPID_KD]);
// Compute desired east command
eastError = velocityDesired.East - velocityActual.East;
eastVelIntegral = bound(eastVelIntegral + eastError * dT * guidanceSettings.HorizontalVelPID[GUIDANCESETTINGS_HORIZONTALVELPID_KI],
-guidanceSettings.HorizontalVelPID[GUIDANCESETTINGS_HORIZONTALVELPID_ILIMIT],
guidanceSettings.HorizontalVelPID[GUIDANCESETTINGS_HORIZONTALVELPID_ILIMIT]);
eastCommand = (eastError * guidanceSettings.HorizontalVelPID[GUIDANCESETTINGS_HORIZONTALVELPID_KP] +
eastVelIntegral -
nedAccel.East * guidanceSettings.HorizontalVelPID[GUIDANCESETTINGS_HORIZONTALVELPID_KD]);
// Compute desired down command
downError = velocityDesired.Down - velocityActual.Down;
downVelIntegral = bound(downVelIntegral + downError * dT * guidanceSettings.VerticalVelPID[GUIDANCESETTINGS_VERTICALVELPID_KI],
-guidanceSettings.VerticalVelPID[GUIDANCESETTINGS_VERTICALVELPID_ILIMIT],
guidanceSettings.VerticalVelPID[GUIDANCESETTINGS_VERTICALVELPID_ILIMIT]);
downCommand = (downError * guidanceSettings.VerticalVelPID[GUIDANCESETTINGS_VERTICALVELPID_KP] +
downVelIntegral -
nedAccel.Down * guidanceSettings.VerticalVelPID[GUIDANCESETTINGS_VERTICALVELPID_KD]);
stabDesired.Throttle = bound(downCommand, 0, 1);
// Project the north and east command signals into the pitch and roll based on yaw. For this to behave well the
// craft should move similarly for 5 deg roll versus 5 deg pitch
stabDesired.Pitch = bound(-northCommand * cosf(attitudeActual.Yaw * M_PI / 180) +
-eastCommand * sinf(attitudeActual.Yaw * M_PI / 180),
-guidanceSettings.MaxRollPitch, guidanceSettings.MaxRollPitch);
stabDesired.Roll = bound(-northCommand * sinf(attitudeActual.Yaw * M_PI / 180) +
eastCommand * cosf(attitudeActual.Yaw * M_PI / 180),
-guidanceSettings.MaxRollPitch, guidanceSettings.MaxRollPitch);
if(guidanceSettings.ThrottleControl == GUIDANCESETTINGS_THROTTLECONTROL_FALSE) {
// For now override throttle with manual control. Disable at your risk, quad goes to China.
ManualControlCommandData manualControl;
ManualControlCommandGet(&manualControl);
stabDesired.Throttle = manualControl.Throttle;
}
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_ROLL] = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_PITCH] = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_YAW] = STABILIZATIONDESIRED_STABILIZATIONMODE_RATE;
StabilizationDesiredSet(&stabDesired);
}
int8_t VtolFlyController::UpdateStabilizationDesired(bool yaw_attitude, float yaw_direction)
{
uint8_t result = 1;
StabilizationDesiredData stabDesired;
AttitudeStateData attitudeState;
StabilizationBankData stabSettings;
float northCommand;
float eastCommand;
StabilizationDesiredGet(&stabDesired);
AttitudeStateGet(&attitudeState);
StabilizationBankGet(&stabSettings);
controlNE.GetNECommand(&northCommand, &eastCommand);
float angle_radians = DEG2RAD(attitudeState.Yaw);
float cos_angle = cosf(angle_radians);
float sine_angle = sinf(angle_radians);
float maxPitch = vtolPathFollowerSettings->MaxRollPitch;
stabDesired.StabilizationMode.Pitch = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabDesired.Pitch = boundf(-northCommand * cos_angle - eastCommand * sine_angle, -maxPitch, maxPitch); // this should be in the controller
stabDesired.StabilizationMode.Roll = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabDesired.Roll = boundf(-northCommand * sine_angle + eastCommand * cos_angle, -maxPitch, maxPitch);
ManualControlCommandData manualControl;
ManualControlCommandGet(&manualControl);
// TODO The below need to be rewritten because the PID implementation has changed.
#if 0
// DEBUG HACK: allow user to skew compass on purpose to see if emergency failsafe kicks in
if (vtolPathFollowerSettings->FlyawayEmergencyFallback == VTOLPATHFOLLOWERSETTINGS_FLYAWAYEMERGENCYFALLBACK_DEBUGTEST) {
attitudeState.Yaw += 120.0f;
if (attitudeState.Yaw > 180.0f) {
attitudeState.Yaw -= 360.0f;
}
}
if ( // emergency flyaway detection
( // integral already at its limit
vtolPathFollowerSettings.HorizontalVelPID.ILimit - fabsf(global.PIDvel[0].iAccumulator) < 1e-6f ||
vtolPathFollowerSettings.HorizontalVelPID.ILimit - fabsf(global.PIDvel[1].iAccumulator) < 1e-6f
) &&
// angle between desired and actual velocity >90 degrees (by dot product)
(velocityDesired.North * velocityState.North + velocityDesired.East * velocityState.East < 0.0f) &&
// quad is moving at significant speed (during flyaway it would keep speeding up)
squaref(velocityState.North) + squaref(velocityState.East) > 1.0f
) {
vtolEmergencyFallback += dT;
if (vtolEmergencyFallback >= vtolPathFollowerSettings->FlyawayEmergencyFallbackTriggerTime) {
// after emergency timeout, trigger alarm - everything else is handled by callers
// (switch to emergency algorithm, switch to emergency waypoint in pathplanner, alarms, ...)
result = 0;
}
} else {
vtolEmergencyFallback = 0.0f;
}
#endif // if 0
if (yaw_attitude) {
stabDesired.StabilizationMode.Yaw = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabDesired.Yaw = yaw_direction;
} else {
stabDesired.StabilizationMode.Yaw = STABILIZATIONDESIRED_STABILIZATIONMODE_AXISLOCK;
stabDesired.Yaw = stabSettings.MaximumRate.Yaw * manualControl.Yaw;
}
// default thrust mode to cruise control
stabDesired.StabilizationMode.Thrust = STABILIZATIONDESIRED_STABILIZATIONMODE_CRUISECONTROL;
if (mManualThrust) {
stabDesired.Thrust = manualControl.Thrust;
} else {
stabDesired.Thrust = controlDown.GetDownCommand();
}
StabilizationDesiredSet(&stabDesired);
return result;
}
/**
* Module task
*/
static void stabilizationTask(void* parameters)
{
portTickType lastSysTime;
portTickType thisSysTime;
UAVObjEvent ev;
ActuatorDesiredData actuatorDesired;
StabilizationDesiredData stabDesired;
RateDesiredData rateDesired;
AttitudeActualData attitudeActual;
AttitudeRawData attitudeRaw;
SystemSettingsData systemSettings;
FlightStatusData flightStatus;
SettingsUpdatedCb((UAVObjEvent *) NULL);
// Main task loop
lastSysTime = xTaskGetTickCount();
ZeroPids();
while(1) {
PIOS_WDG_UpdateFlag(PIOS_WDG_STABILIZATION);
// Wait until the AttitudeRaw object is updated, if a timeout then go to failsafe
if ( xQueueReceive(queue, &ev, FAILSAFE_TIMEOUT_MS / portTICK_RATE_MS) != pdTRUE )
{
AlarmsSet(SYSTEMALARMS_ALARM_STABILIZATION,SYSTEMALARMS_ALARM_WARNING);
continue;
}
// Check how long since last update
thisSysTime = xTaskGetTickCount();
if(thisSysTime > lastSysTime) // reuse dt in case of wraparound
dT = (thisSysTime - lastSysTime) / portTICK_RATE_MS / 1000.0f;
lastSysTime = thisSysTime;
FlightStatusGet(&flightStatus);
StabilizationDesiredGet(&stabDesired);
AttitudeActualGet(&attitudeActual);
AttitudeRawGet(&attitudeRaw);
RateDesiredGet(&rateDesired);
SystemSettingsGet(&systemSettings);
#if defined(PIOS_QUATERNION_STABILIZATION)
// Quaternion calculation of error in each axis. Uses more memory.
float rpy_desired[3];
float q_desired[4];
float q_error[4];
float local_error[3];
// Essentially zero errors for anything in rate or none
if(stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_ROLL] == STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE)
rpy_desired[0] = stabDesired.Roll;
else
rpy_desired[0] = attitudeActual.Roll;
if(stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_PITCH] == STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE)
rpy_desired[1] = stabDesired.Pitch;
else
rpy_desired[1] = attitudeActual.Pitch;
if(stabDesired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_YAW] == STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE)
rpy_desired[2] = stabDesired.Yaw;
else
rpy_desired[2] = attitudeActual.Yaw;
RPY2Quaternion(rpy_desired, q_desired);
quat_inverse(q_desired);
quat_mult(q_desired, &attitudeActual.q1, q_error);
quat_inverse(q_error);
Quaternion2RPY(q_error, local_error);
#else
// Simpler algorithm for CC, less memory
float local_error[3] = {stabDesired.Roll - attitudeActual.Roll,
stabDesired.Pitch - attitudeActual.Pitch,
stabDesired.Yaw - attitudeActual.Yaw};
local_error[2] = fmod(local_error[2] + 180, 360) - 180;
#endif
for(uint8_t i = 0; i < MAX_AXES; i++) {
gyro_filtered[i] = gyro_filtered[i] * gyro_alpha + attitudeRaw.gyros[i] * (1 - gyro_alpha);
}
float *attitudeDesiredAxis = &stabDesired.Roll;
float *actuatorDesiredAxis = &actuatorDesired.Roll;
float *rateDesiredAxis = &rateDesired.Roll;
//Calculate desired rate
for(uint8_t i=0; i< MAX_AXES; i++)
{
switch(stabDesired.StabilizationMode[i])
{
case STABILIZATIONDESIRED_STABILIZATIONMODE_RATE:
rateDesiredAxis[i] = attitudeDesiredAxis[i];
axis_lock_accum[i] = 0;
break;
case STABILIZATIONDESIRED_STABILIZATIONMODE_WEAKLEVELING:
{
float weak_leveling = local_error[i] * weak_leveling_kp;
if(weak_leveling > weak_leveling_max)
weak_leveling = weak_leveling_max;
if(weak_leveling < -weak_leveling_max)
weak_leveling = -weak_leveling_max;
rateDesiredAxis[i] = attitudeDesiredAxis[i] + weak_leveling;
axis_lock_accum[i] = 0;
break;
}
case STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE:
rateDesiredAxis[i] = ApplyPid(&pids[PID_ROLL + i], local_error[i]);
axis_lock_accum[i] = 0;
break;
case STABILIZATIONDESIRED_STABILIZATIONMODE_AXISLOCK:
if(fabs(attitudeDesiredAxis[i]) > max_axislock_rate) {
// While getting strong commands act like rate mode
rateDesiredAxis[i] = attitudeDesiredAxis[i];
axis_lock_accum[i] = 0;
} else {
// For weaker commands or no command simply attitude lock (almost) on no gyro change
axis_lock_accum[i] += (attitudeDesiredAxis[i] - gyro_filtered[i]) * dT;
if(axis_lock_accum[i] > max_axis_lock)
axis_lock_accum[i] = max_axis_lock;
else if(axis_lock_accum[i] < -max_axis_lock)
axis_lock_accum[i] = -max_axis_lock;
rateDesiredAxis[i] = ApplyPid(&pids[PID_ROLL + i], axis_lock_accum[i]);
}
break;
}
}
uint8_t shouldUpdate = 1;
RateDesiredSet(&rateDesired);
ActuatorDesiredGet(&actuatorDesired);
//Calculate desired command
for(int8_t ct=0; ct< MAX_AXES; ct++)
{
if(rateDesiredAxis[ct] > settings.MaximumRate[ct])
rateDesiredAxis[ct] = settings.MaximumRate[ct];
else if(rateDesiredAxis[ct] < -settings.MaximumRate[ct])
rateDesiredAxis[ct] = -settings.MaximumRate[ct];
switch(stabDesired.StabilizationMode[ct])
{
case STABILIZATIONDESIRED_STABILIZATIONMODE_RATE:
case STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE:
case STABILIZATIONDESIRED_STABILIZATIONMODE_AXISLOCK:
case STABILIZATIONDESIRED_STABILIZATIONMODE_WEAKLEVELING:
{
float command = ApplyPid(&pids[PID_RATE_ROLL + ct], rateDesiredAxis[ct] - gyro_filtered[ct]);
actuatorDesiredAxis[ct] = bound(command);
break;
}
case STABILIZATIONDESIRED_STABILIZATIONMODE_NONE:
switch (ct)
{
case ROLL:
actuatorDesiredAxis[ct] = bound(attitudeDesiredAxis[ct]);
shouldUpdate = 1;
break;
case PITCH:
actuatorDesiredAxis[ct] = bound(attitudeDesiredAxis[ct]);
shouldUpdate = 1;
break;
case YAW:
actuatorDesiredAxis[ct] = bound(attitudeDesiredAxis[ct]);
shouldUpdate = 1;
break;
}
break;
}
}
// Save dT
actuatorDesired.UpdateTime = dT * 1000;
if(PARSE_FLIGHT_MODE(flightStatus.FlightMode) == FLIGHTMODE_MANUAL)
shouldUpdate = 0;
if(shouldUpdate)
{
actuatorDesired.Throttle = stabDesired.Throttle;
if(dT > 15)
actuatorDesired.NumLongUpdates++;
ActuatorDesiredSet(&actuatorDesired);
}
if(flightStatus.Armed != FLIGHTSTATUS_ARMED_ARMED ||
(lowThrottleZeroIntegral && stabDesired.Throttle < 0) ||
!shouldUpdate)
{
ZeroPids();
}
// Clear alarms
AlarmsClear(SYSTEMALARMS_ALARM_STABILIZATION);
}
}
/**
* Select and use failsafe control
* @param [in] reset_controller True if previously another controller was used
*/
int32_t failsafe_control_select(bool reset_controller)
{
if (reset_controller) {
FlightStatusArmedOptions armed;
FlightStatusArmedGet(&armed);
armed_when_enabled = (armed == FLIGHTSTATUS_ARMED_ARMED);
rth_active = false;
/* Get configured failsafe behavior */
uint8_t failsafe_behavior;
ManualControlSettingsFailsafeBehaviorGet(&failsafe_behavior);
/* check whether RTH failsafe is configured and can be used */
if (failsafe_behavior == MANUALCONTROLSETTINGS_FAILSAFEBEHAVIOR_RTH
&& check_rth_preconditions_met())
rth_active = true;
}
uint8_t flight_mode_desired = rth_active ? FLIGHTSTATUS_FLIGHTMODE_RETURNTOHOME : FLIGHTSTATUS_FLIGHTMODE_STABILIZED1;
uint8_t flight_mode_actual;
FlightStatusFlightModeGet(&flight_mode_actual);
if (flight_mode_actual != flight_mode_desired || reset_controller) {
FlightStatusFlightModeSet(&flight_mode_desired);
}
#ifdef GIMBAL
// Gimbals do not need failsafe
StabilizationDesiredData stabilization_desired;
StabilizationDesiredGet(&stabilization_desired);
stabilization_desired.Throttle = -1;
stabilization_desired.Roll = 0;
stabilization_desired.Pitch = 0;
stabilization_desired.Yaw = 0;
stabilization_desired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_ROLL] = STABILIZATIONDESIRED_STABILIZATIONMODE_POI;
stabilization_desired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_PITCH] = STABILIZATIONDESIRED_STABILIZATIONMODE_POI;
stabilization_desired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_YAW] = STABILIZATIONDESIRED_STABILIZATIONMODE_AXISLOCK;
StabilizationDesiredSet(&stabilization_desired);
#else
if (!rth_active) {
// Pick default values that will roughly cause a plane to circle down
// and a quad to fall straight down
StabilizationDesiredData stabilization_desired;
StabilizationDesiredGet(&stabilization_desired);
if (!armed_when_enabled) {
/* disable stabilization so outputs do not move when system was not armed */
stabilization_desired.Throttle = -1;
stabilization_desired.Roll = 0;
stabilization_desired.Pitch = 0;
stabilization_desired.Yaw = 0;
stabilization_desired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_ROLL] = STABILIZATIONDESIRED_STABILIZATIONMODE_NONE;
stabilization_desired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_PITCH] = STABILIZATIONDESIRED_STABILIZATIONMODE_NONE;
stabilization_desired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_YAW] = STABILIZATIONDESIRED_STABILIZATIONMODE_NONE;
} else {
/* Pick default values that will roughly cause a plane to circle down and */
/* a quad to fall straight down */
stabilization_desired.Throttle = -1;
stabilization_desired.Roll = -10;
stabilization_desired.Pitch = 0;
stabilization_desired.Yaw = -5;
stabilization_desired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_ROLL] = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabilization_desired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_PITCH] = STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE;
stabilization_desired.StabilizationMode[STABILIZATIONDESIRED_STABILIZATIONMODE_YAW] = STABILIZATIONDESIRED_STABILIZATIONMODE_RATE;
}
StabilizationDesiredSet(&stabilization_desired);
}
#endif
return 0;
}
/**
* Module task
*/
static void stabilizationTask(void* parameters)
{
UAVObjEvent ev;
uint32_t timeval = PIOS_DELAY_GetRaw();
ActuatorDesiredData actuatorDesired;
StabilizationDesiredData stabDesired;
RateDesiredData rateDesired;
AttitudeActualData attitudeActual;
GyrosData gyrosData;
FlightStatusData flightStatus;
float *stabDesiredAxis = &stabDesired.Roll;
float *actuatorDesiredAxis = &actuatorDesired.Roll;
float *rateDesiredAxis = &rateDesired.Roll;
float horizonRateFraction = 0.0f;
// Force refresh of all settings immediately before entering main task loop
SettingsUpdatedCb((UAVObjEvent *) NULL);
// Settings for system identification
uint32_t iteration = 0;
const uint32_t SYSTEM_IDENT_PERIOD = 75;
uint32_t system_ident_timeval = PIOS_DELAY_GetRaw();
float dT_filtered = 0;
// Main task loop
zero_pids();
while(1) {
iteration++;
PIOS_WDG_UpdateFlag(PIOS_WDG_STABILIZATION);
// Wait until the AttitudeRaw object is updated, if a timeout then go to failsafe
if (PIOS_Queue_Receive(queue, &ev, FAILSAFE_TIMEOUT_MS) != true)
{
AlarmsSet(SYSTEMALARMS_ALARM_STABILIZATION,SYSTEMALARMS_ALARM_WARNING);
continue;
}
calculate_pids();
float dT = PIOS_DELAY_DiffuS(timeval) * 1.0e-6f;
timeval = PIOS_DELAY_GetRaw();
// exponential moving averaging (EMA) of dT to reduce jitter; ~200points
// to have more or less equivalent noise reduction to a normal N point moving averaging: alpha = 2 / (N + 1)
// run it only at the beginning for the first samples, to reduce CPU load, and the value should converge to a constant value
if (iteration < 100) {
dT_filtered = dT;
} else if (iteration < 2000) {
dT_filtered = 0.01f * dT + (1.0f - 0.01f) * dT_filtered;
} else if (iteration == 2000) {
gyro_filter_updated = true;
}
if (gyro_filter_updated) {
if (settings.GyroCutoff < 1.0f) {
gyro_alpha = 0;
} else {
gyro_alpha = expf(-2.0f * (float)(M_PI) *
settings.GyroCutoff * dT_filtered);
}
// Compute time constant for vbar decay term
if (settings.VbarTau < 0.001f) {
vbar_decay = 0;
} else {
vbar_decay = expf(-dT_filtered / settings.VbarTau);
}
gyro_filter_updated = false;
}
FlightStatusGet(&flightStatus);
StabilizationDesiredGet(&stabDesired);
AttitudeActualGet(&attitudeActual);
GyrosGet(&gyrosData);
ActuatorDesiredGet(&actuatorDesired);
#if defined(RATEDESIRED_DIAGNOSTICS)
RateDesiredGet(&rateDesired);
#endif
struct TrimmedAttitudeSetpoint {
float Roll;
float Pitch;
float Yaw;
} trimmedAttitudeSetpoint;
// Mux in level trim values, and saturate the trimmed attitude setpoint.
trimmedAttitudeSetpoint.Roll = bound_min_max(
stabDesired.Roll + trimAngles.Roll,
-settings.RollMax + trimAngles.Roll,
settings.RollMax + trimAngles.Roll);
trimmedAttitudeSetpoint.Pitch = bound_min_max(
stabDesired.Pitch + trimAngles.Pitch,
-settings.PitchMax + trimAngles.Pitch,
settings.PitchMax + trimAngles.Pitch);
trimmedAttitudeSetpoint.Yaw = stabDesired.Yaw;
// For horizon mode we need to compute the desire attitude from an unscaled value and apply the
// trim offset. Also track the stick with the most deflection to choose rate blending.
horizonRateFraction = 0.0f;
if (stabDesired.StabilizationMode[ROLL] == STABILIZATIONDESIRED_STABILIZATIONMODE_HORIZON) {
trimmedAttitudeSetpoint.Roll = bound_min_max(
stabDesired.Roll * settings.RollMax + trimAngles.Roll,
-settings.RollMax + trimAngles.Roll,
settings.RollMax + trimAngles.Roll);
horizonRateFraction = fabsf(stabDesired.Roll);
}
if (stabDesired.StabilizationMode[PITCH] == STABILIZATIONDESIRED_STABILIZATIONMODE_HORIZON) {
trimmedAttitudeSetpoint.Pitch = bound_min_max(
stabDesired.Pitch * settings.PitchMax + trimAngles.Pitch,
-settings.PitchMax + trimAngles.Pitch,
settings.PitchMax + trimAngles.Pitch);
horizonRateFraction = MAX(horizonRateFraction, fabsf(stabDesired.Pitch));
}
if (stabDesired.StabilizationMode[YAW] == STABILIZATIONDESIRED_STABILIZATIONMODE_HORIZON) {
trimmedAttitudeSetpoint.Yaw = stabDesired.Yaw * settings.YawMax;
horizonRateFraction = MAX(horizonRateFraction, fabsf(stabDesired.Yaw));
}
// For weak leveling mode the attitude setpoint is the trim value (drifts back towards "0")
if (stabDesired.StabilizationMode[ROLL] == STABILIZATIONDESIRED_STABILIZATIONMODE_WEAKLEVELING) {
trimmedAttitudeSetpoint.Roll = trimAngles.Roll;
}
if (stabDesired.StabilizationMode[PITCH] == STABILIZATIONDESIRED_STABILIZATIONMODE_WEAKLEVELING) {
trimmedAttitudeSetpoint.Pitch = trimAngles.Pitch;
}
if (stabDesired.StabilizationMode[YAW] == STABILIZATIONDESIRED_STABILIZATIONMODE_WEAKLEVELING) {
trimmedAttitudeSetpoint.Yaw = 0;
}
// Note we divide by the maximum limit here so the fraction ranges from 0 to 1 depending on
// how much is requested.
horizonRateFraction = bound_sym(horizonRateFraction, HORIZON_MODE_MAX_BLEND) / HORIZON_MODE_MAX_BLEND;
// Calculate the errors in each axis. The local error is used in the following modes:
// ATTITUDE, HORIZON, WEAKLEVELING
float local_attitude_error[3];
local_attitude_error[0] = trimmedAttitudeSetpoint.Roll - attitudeActual.Roll;
local_attitude_error[1] = trimmedAttitudeSetpoint.Pitch - attitudeActual.Pitch;
local_attitude_error[2] = trimmedAttitudeSetpoint.Yaw - attitudeActual.Yaw;
// Wrap yaw error to [-180,180]
local_attitude_error[2] = circular_modulus_deg(local_attitude_error[2]);
static float gyro_filtered[3];
gyro_filtered[0] = gyro_filtered[0] * gyro_alpha + gyrosData.x * (1 - gyro_alpha);
gyro_filtered[1] = gyro_filtered[1] * gyro_alpha + gyrosData.y * (1 - gyro_alpha);
gyro_filtered[2] = gyro_filtered[2] * gyro_alpha + gyrosData.z * (1 - gyro_alpha);
// A flag to track which stabilization mode each axis is in
static uint8_t previous_mode[MAX_AXES] = {255,255,255};
bool error = false;
//Run the selected stabilization algorithm on each axis:
for(uint8_t i=0; i< MAX_AXES; i++)
{
// Check whether this axis mode needs to be reinitialized
bool reinit = (stabDesired.StabilizationMode[i] != previous_mode[i]);
// The unscaled input (-1,1)
float *raw_input = &stabDesired.Roll;
previous_mode[i] = stabDesired.StabilizationMode[i];
// Apply the selected control law
switch(stabDesired.StabilizationMode[i])
{
case STABILIZATIONDESIRED_STABILIZATIONMODE_RATE:
if(reinit)
pids[PID_GROUP_RATE + i].iAccumulator = 0;
// Store to rate desired variable for storing to UAVO
rateDesiredAxis[i] = bound_sym(stabDesiredAxis[i], settings.ManualRate[i]);
// Compute the inner loop
actuatorDesiredAxis[i] = pid_apply_setpoint(&pids[PID_GROUP_RATE + i], rateDesiredAxis[i], gyro_filtered[i], dT);
actuatorDesiredAxis[i] = bound_sym(actuatorDesiredAxis[i],1.0f);
break;
case STABILIZATIONDESIRED_STABILIZATIONMODE_ACROPLUS:
// this implementation is based on the Openpilot/Librepilot Acro+ flightmode
// and our existing rate & MWRate flightmodes
if(reinit)
pids[PID_GROUP_RATE + i].iAccumulator = 0;
// The factor for gyro suppression / mixing raw stick input into the output; scaled by raw stick input
float factor = fabsf(raw_input[i]) * settings.AcroInsanityFactor / 100;
// Store to rate desired variable for storing to UAVO
rateDesiredAxis[i] = bound_sym(raw_input[i] * settings.ManualRate[i], settings.ManualRate[i]);
// Zero integral for aggressive maneuvers, like it is done for MWRate
if ((i < 2 && fabsf(gyro_filtered[i]) > 150.0f) ||
(i == 0 && fabsf(raw_input[i]) > 0.2f)) {
pids[PID_GROUP_RATE + i].iAccumulator = 0;
pids[PID_GROUP_RATE + i].i = 0;
}
// Compute the inner loop
actuatorDesiredAxis[i] = pid_apply_setpoint(&pids[PID_GROUP_RATE + i], rateDesiredAxis[i], gyro_filtered[i], dT);
actuatorDesiredAxis[i] = factor * raw_input[i] + (1.0f - factor) * actuatorDesiredAxis[i];
actuatorDesiredAxis[i] = bound_sym(actuatorDesiredAxis[i], 1.0f);
break;
case STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE:
if(reinit) {
pids[PID_GROUP_ATT + i].iAccumulator = 0;
pids[PID_GROUP_RATE + i].iAccumulator = 0;
}
// Compute the outer loop
rateDesiredAxis[i] = pid_apply(&pids[PID_GROUP_ATT + i], local_attitude_error[i], dT);
rateDesiredAxis[i] = bound_sym(rateDesiredAxis[i], settings.MaximumRate[i]);
// Compute the inner loop
actuatorDesiredAxis[i] = pid_apply_setpoint(&pids[PID_GROUP_RATE + i], rateDesiredAxis[i], gyro_filtered[i], dT);
actuatorDesiredAxis[i] = bound_sym(actuatorDesiredAxis[i],1.0f);
break;
case STABILIZATIONDESIRED_STABILIZATIONMODE_VIRTUALBAR:
// Store for debugging output
rateDesiredAxis[i] = stabDesiredAxis[i];
// Run a virtual flybar stabilization algorithm on this axis
stabilization_virtual_flybar(gyro_filtered[i], rateDesiredAxis[i], &actuatorDesiredAxis[i], dT, reinit, i, &pids[PID_GROUP_VBAR + i], &settings);
break;
case STABILIZATIONDESIRED_STABILIZATIONMODE_WEAKLEVELING:
{
if (reinit)
pids[PID_GROUP_RATE + i].iAccumulator = 0;
float weak_leveling = local_attitude_error[i] * weak_leveling_kp;
weak_leveling = bound_sym(weak_leveling, weak_leveling_max);
// Compute desired rate as input biased towards leveling
rateDesiredAxis[i] = stabDesiredAxis[i] + weak_leveling;
actuatorDesiredAxis[i] = pid_apply_setpoint(&pids[PID_GROUP_RATE + i], rateDesiredAxis[i], gyro_filtered[i], dT);
actuatorDesiredAxis[i] = bound_sym(actuatorDesiredAxis[i],1.0f);
break;
}
case STABILIZATIONDESIRED_STABILIZATIONMODE_AXISLOCK:
if (reinit)
pids[PID_GROUP_RATE + i].iAccumulator = 0;
if (fabsf(stabDesiredAxis[i]) > max_axislock_rate) {
// While getting strong commands act like rate mode
rateDesiredAxis[i] = bound_sym(stabDesiredAxis[i], settings.ManualRate[i]);
// Reset accumulator
axis_lock_accum[i] = 0;
} else {
// For weaker commands or no command simply lock (almost) on no gyro change
axis_lock_accum[i] += (stabDesiredAxis[i] - gyro_filtered[i]) * dT;
axis_lock_accum[i] = bound_sym(axis_lock_accum[i], max_axis_lock);
// Compute the inner loop
float tmpRateDesired = pid_apply(&pids[PID_GROUP_ATT + i], axis_lock_accum[i], dT);
rateDesiredAxis[i] = bound_sym(tmpRateDesired, settings.MaximumRate[i]);
}
actuatorDesiredAxis[i] = pid_apply_setpoint(&pids[PID_GROUP_RATE + i], rateDesiredAxis[i], gyro_filtered[i], dT);
actuatorDesiredAxis[i] = bound_sym(actuatorDesiredAxis[i],1.0f);
break;
case STABILIZATIONDESIRED_STABILIZATIONMODE_HORIZON:
if(reinit) {
pids[PID_GROUP_RATE + i].iAccumulator = 0;
}
// Do not allow outer loop integral to wind up in this mode since the controller
// is often disengaged.
pids[PID_GROUP_ATT + i].iAccumulator = 0;
// Compute the outer loop for the attitude control
float rateDesiredAttitude = pid_apply(&pids[PID_GROUP_ATT + i], local_attitude_error[i], dT);
// Compute the desire rate for a rate control
float rateDesiredRate = raw_input[i] * settings.ManualRate[i];
// Blend from one rate to another. The maximum of all stick positions is used for the
// amount so that when one axis goes completely to rate the other one does too. This
// prevents doing flips while one axis tries to stay in attitude mode.
rateDesiredAxis[i] = rateDesiredAttitude * (1.0f-horizonRateFraction) + rateDesiredRate * horizonRateFraction;
rateDesiredAxis[i] = bound_sym(rateDesiredAxis[i], settings.ManualRate[i]);
// Compute the inner loop
actuatorDesiredAxis[i] = pid_apply_setpoint(&pids[PID_GROUP_RATE + i], rateDesiredAxis[i], gyro_filtered[i], dT);
actuatorDesiredAxis[i] = bound_sym(actuatorDesiredAxis[i],1.0f);
break;
case STABILIZATIONDESIRED_STABILIZATIONMODE_MWRATE:
{
if(reinit) {
pids[PID_GROUP_MWR + i].iAccumulator = 0;
}
/*
Conversion from MultiWii PID settings to our units.
Kp = Kp_mw * 4 / 80 / 500
Kd = Kd_mw * looptime * 1e-6 * 4 * 3 / 32 / 500
Ki = Ki_mw * 4 / 125 / 64 / (looptime * 1e-6) / 500
These values will just be approximate and should help
you get started.
*/
// The unscaled input (-1,1) - note in MW this is from (-500,500)
float *raw_input = &stabDesired.Roll;
// dynamic PIDs are scaled both by throttle and stick position
float scale = (i == 0 || i == 1) ? mwrate_settings.RollPitchRate : mwrate_settings.YawRate;
float pid_scale = (100.0f - scale * fabsf(raw_input[i])) / 100.0f;
float dynP8 = pids[PID_GROUP_MWR + i].p * pid_scale;
float dynD8 = pids[PID_GROUP_MWR + i].d * pid_scale;
// these terms are used by the integral loop this proportional term is scaled by throttle (this is different than MW
// that does not apply scale
float cfgP8 = pids[PID_GROUP_MWR + i].p;
float cfgI8 = pids[PID_GROUP_MWR + i].i;
// Dynamically adjust PID settings
struct pid mw_pid;
mw_pid.p = 0; // use zero Kp here because of strange setpoint. applied later.
mw_pid.d = dynD8;
mw_pid.i = cfgI8;
mw_pid.iLim = pids[PID_GROUP_MWR + i].iLim;
mw_pid.iAccumulator = pids[PID_GROUP_MWR + i].iAccumulator;
mw_pid.lastErr = pids[PID_GROUP_MWR + i].lastErr;
mw_pid.lastDer = pids[PID_GROUP_MWR + i].lastDer;
// Zero integral for aggressive maneuvers
if ((i < 2 && fabsf(gyro_filtered[i]) > 150.0f) ||
(i == 0 && fabsf(raw_input[i]) > 0.2f)) {
mw_pid.iAccumulator = 0;
mw_pid.i = 0;
}
// Apply controller as if we want zero change, then add stick input afterwards
actuatorDesiredAxis[i] = pid_apply_setpoint(&mw_pid, raw_input[i] / cfgP8, gyro_filtered[i], dT);
actuatorDesiredAxis[i] += raw_input[i]; // apply input
actuatorDesiredAxis[i] -= dynP8 * gyro_filtered[i]; // apply Kp term
actuatorDesiredAxis[i] = bound_sym(actuatorDesiredAxis[i],1.0f);
// Store PID accumulators for next cycle
pids[PID_GROUP_MWR + i].iAccumulator = mw_pid.iAccumulator;
pids[PID_GROUP_MWR + i].lastErr = mw_pid.lastErr;
pids[PID_GROUP_MWR + i].lastDer = mw_pid.lastDer;
}
break;
case STABILIZATIONDESIRED_STABILIZATIONMODE_SYSTEMIDENT:
if(reinit) {
pids[PID_GROUP_ATT + i].iAccumulator = 0;
pids[PID_GROUP_RATE + i].iAccumulator = 0;
}
static uint32_t ident_iteration = 0;
static float ident_offsets[3] = {0};
if (PIOS_DELAY_DiffuS(system_ident_timeval) / 1000.0f > SYSTEM_IDENT_PERIOD && SystemIdentHandle()) {
ident_iteration++;
system_ident_timeval = PIOS_DELAY_GetRaw();
SystemIdentData systemIdent;
SystemIdentGet(&systemIdent);
const float SCALE_BIAS = 7.1f;
float roll_scale = expf(SCALE_BIAS - systemIdent.Beta[SYSTEMIDENT_BETA_ROLL]);
float pitch_scale = expf(SCALE_BIAS - systemIdent.Beta[SYSTEMIDENT_BETA_PITCH]);
float yaw_scale = expf(SCALE_BIAS - systemIdent.Beta[SYSTEMIDENT_BETA_YAW]);
if (roll_scale > 0.25f)
roll_scale = 0.25f;
if (pitch_scale > 0.25f)
pitch_scale = 0.25f;
if (yaw_scale > 0.25f)
yaw_scale = 0.2f;
switch(ident_iteration & 0x07) {
case 0:
ident_offsets[0] = 0;
ident_offsets[1] = 0;
ident_offsets[2] = yaw_scale;
break;
case 1:
ident_offsets[0] = roll_scale;
ident_offsets[1] = 0;
ident_offsets[2] = 0;
break;
case 2:
ident_offsets[0] = 0;
ident_offsets[1] = 0;
ident_offsets[2] = -yaw_scale;
break;
case 3:
ident_offsets[0] = -roll_scale;
ident_offsets[1] = 0;
ident_offsets[2] = 0;
break;
case 4:
ident_offsets[0] = 0;
ident_offsets[1] = 0;
ident_offsets[2] = yaw_scale;
break;
case 5:
ident_offsets[0] = 0;
ident_offsets[1] = pitch_scale;
ident_offsets[2] = 0;
break;
case 6:
ident_offsets[0] = 0;
ident_offsets[1] = 0;
ident_offsets[2] = -yaw_scale;
break;
case 7:
ident_offsets[0] = 0;
ident_offsets[1] = -pitch_scale;
ident_offsets[2] = 0;
break;
}
}
if (i == ROLL || i == PITCH) {
// Compute the outer loop
rateDesiredAxis[i] = pid_apply(&pids[PID_GROUP_ATT + i], local_attitude_error[i], dT);
rateDesiredAxis[i] = bound_sym(rateDesiredAxis[i], settings.MaximumRate[i]);
// Compute the inner loop
actuatorDesiredAxis[i] = pid_apply_setpoint(&pids[PID_GROUP_RATE + i], rateDesiredAxis[i], gyro_filtered[i], dT);
actuatorDesiredAxis[i] += ident_offsets[i];
actuatorDesiredAxis[i] = bound_sym(actuatorDesiredAxis[i],1.0f);
} else {
// Get the desired rate. yaw is always in rate mode in system ident.
rateDesiredAxis[i] = bound_sym(stabDesiredAxis[i], settings.ManualRate[i]);
// Compute the inner loop only for yaw
actuatorDesiredAxis[i] = pid_apply_setpoint(&pids[PID_GROUP_RATE + i], rateDesiredAxis[i], gyro_filtered[i], dT);
actuatorDesiredAxis[i] += ident_offsets[i];
actuatorDesiredAxis[i] = bound_sym(actuatorDesiredAxis[i],1.0f);
}
break;
case STABILIZATIONDESIRED_STABILIZATIONMODE_COORDINATEDFLIGHT:
switch (i) {
case YAW:
if (reinit) {
pids[PID_COORDINATED_FLIGHT_YAW].iAccumulator = 0;
pids[PID_RATE_YAW].iAccumulator = 0;
axis_lock_accum[YAW] = 0;
}
//If we are not in roll attitude mode, trigger an error
if (stabDesired.StabilizationMode[ROLL] != STABILIZATIONDESIRED_STABILIZATIONMODE_ATTITUDE)
{
error = true;
break ;
}
if (fabsf(stabDesired.Yaw) < COORDINATED_FLIGHT_MAX_YAW_THRESHOLD) { //If yaw is within the deadband...
if (fabsf(stabDesired.Roll) > COORDINATED_FLIGHT_MIN_ROLL_THRESHOLD) { // We're requesting more roll than the threshold
float accelsDataY;
AccelsyGet(&accelsDataY);
//Reset integral if we have changed roll to opposite direction from rudder. This implies that we have changed desired turning direction.
if ((stabDesired.Roll > 0 && actuatorDesiredAxis[YAW] < 0) ||
(stabDesired.Roll < 0 && actuatorDesiredAxis[YAW] > 0)){
pids[PID_COORDINATED_FLIGHT_YAW].iAccumulator = 0;
}
// Coordinate flight can simply be seen as ensuring that there is no lateral acceleration in the
// body frame. As such, we use the (noisy) accelerometer data as our measurement. Ideally, at
// some point in the future we will estimate acceleration and then we can use the estimated value
// instead of the measured value.
float errorSlip = -accelsDataY;
float command = pid_apply(&pids[PID_COORDINATED_FLIGHT_YAW], errorSlip, dT);
actuatorDesiredAxis[YAW] = bound_sym(command ,1.0);
// Reset axis-lock integrals
pids[PID_RATE_YAW].iAccumulator = 0;
axis_lock_accum[YAW] = 0;
} else if (fabsf(stabDesired.Roll) <= COORDINATED_FLIGHT_MIN_ROLL_THRESHOLD) { // We're requesting less roll than the threshold
// Axis lock on no gyro change
axis_lock_accum[YAW] += (0 - gyro_filtered[YAW]) * dT;
rateDesiredAxis[YAW] = pid_apply(&pids[PID_ATT_YAW], axis_lock_accum[YAW], dT);
rateDesiredAxis[YAW] = bound_sym(rateDesiredAxis[YAW], settings.MaximumRate[YAW]);
actuatorDesiredAxis[YAW] = pid_apply_setpoint(&pids[PID_RATE_YAW], rateDesiredAxis[YAW], gyro_filtered[YAW], dT);
actuatorDesiredAxis[YAW] = bound_sym(actuatorDesiredAxis[YAW],1.0f);
// Reset coordinated-flight integral
pids[PID_COORDINATED_FLIGHT_YAW].iAccumulator = 0;
}
} else { //... yaw is outside the deadband. Pass the manual input directly to the actuator.
actuatorDesiredAxis[YAW] = bound_sym(stabDesiredAxis[YAW], 1.0);
// Reset all integrals
pids[PID_COORDINATED_FLIGHT_YAW].iAccumulator = 0;
pids[PID_RATE_YAW].iAccumulator = 0;
axis_lock_accum[YAW] = 0;
}
break;
case ROLL:
case PITCH:
default:
//Coordinated Flight has no effect in these modes. Trigger a configuration error.
error = true;
break;
}
break;
case STABILIZATIONDESIRED_STABILIZATIONMODE_POI:
// The sanity check enforces this is only selectable for Yaw
// for a gimbal you can select pitch too.
if(reinit) {
pids[PID_GROUP_ATT + i].iAccumulator = 0;
pids[PID_GROUP_RATE + i].iAccumulator = 0;
}
float error;
float angle;
if (CameraDesiredHandle()) {
switch(i) {
case PITCH:
CameraDesiredDeclinationGet(&angle);
error = circular_modulus_deg(angle - attitudeActual.Pitch);
break;
case ROLL:
{
uint8_t roll_fraction = 0;
#ifdef GIMBAL
if (BrushlessGimbalSettingsHandle()) {
BrushlessGimbalSettingsRollFractionGet(&roll_fraction);
}
#endif /* GIMBAL */
// For ROLL POI mode we track the FC roll angle (scaled) to
// allow keeping some motion
CameraDesiredRollGet(&angle);
angle *= roll_fraction / 100.0f;
error = circular_modulus_deg(angle - attitudeActual.Roll);
}
break;
case YAW:
CameraDesiredBearingGet(&angle);
error = circular_modulus_deg(angle - attitudeActual.Yaw);
break;
default:
error = true;
}
} else
error = true;
// Compute the outer loop
rateDesiredAxis[i] = pid_apply(&pids[PID_GROUP_ATT + i], error, dT);
rateDesiredAxis[i] = bound_sym(rateDesiredAxis[i], settings.PoiMaximumRate[i]);
// Compute the inner loop
actuatorDesiredAxis[i] = pid_apply_setpoint(&pids[PID_GROUP_RATE + i], rateDesiredAxis[i], gyro_filtered[i], dT);
actuatorDesiredAxis[i] = bound_sym(actuatorDesiredAxis[i],1.0f);
break;
case STABILIZATIONDESIRED_STABILIZATIONMODE_NONE:
actuatorDesiredAxis[i] = bound_sym(stabDesiredAxis[i],1.0f);
break;
default:
error = true;
break;
}
}
if (settings.VbarPiroComp == STABILIZATIONSETTINGS_VBARPIROCOMP_TRUE)
stabilization_virtual_flybar_pirocomp(gyro_filtered[2], dT);
#if defined(RATEDESIRED_DIAGNOSTICS)
RateDesiredSet(&rateDesired);
#endif
// Save dT
actuatorDesired.UpdateTime = dT * 1000;
actuatorDesired.Throttle = stabDesired.Throttle;
if(flightStatus.FlightMode != FLIGHTSTATUS_FLIGHTMODE_MANUAL) {
ActuatorDesiredSet(&actuatorDesired);
} else {
// Force all axes to reinitialize when engaged
for(uint8_t i=0; i< MAX_AXES; i++)
previous_mode[i] = 255;
}
if(flightStatus.Armed != FLIGHTSTATUS_ARMED_ARMED ||
(lowThrottleZeroIntegral && stabDesired.Throttle < 0))
{
// Force all axes to reinitialize when engaged
for(uint8_t i=0; i< MAX_AXES; i++)
previous_mode[i] = 255;
}
// Clear or set alarms. Done like this to prevent toggling each cycle
// and hammering system alarms
if (error)
AlarmsSet(SYSTEMALARMS_ALARM_STABILIZATION,SYSTEMALARMS_ALARM_ERROR);
else
AlarmsClear(SYSTEMALARMS_ALARM_STABILIZATION);
}
}
