static void simulateModelAgnostic()
{
float Rbe[3][3];
float q[4];
// Simulate accels based on current attitude
AttitudeActualData attitudeActual;
AttitudeActualGet(&attitudeActual);
q[0] = attitudeActual.q1;
q[1] = attitudeActual.q2;
q[2] = attitudeActual.q3;
q[3] = attitudeActual.q4;
Quaternion2R(q,Rbe);
AccelsData accelsData; // Skip get as we set all the fields
accelsData.x = -GRAVITY * Rbe[0][2];
accelsData.y = -GRAVITY * Rbe[1][2];
accelsData.z = -GRAVITY * Rbe[2][2];
accelsData.temperature = 30;
AccelsSet(&accelsData);
RateDesiredData rateDesired;
RateDesiredGet(&rateDesired);
GyrosData gyrosData; // Skip get as we set all the fields
gyrosData.x = rateDesired.Roll + rand_gauss();
gyrosData.y = rateDesired.Pitch + rand_gauss();
gyrosData.z = rateDesired.Yaw + rand_gauss();
// Apply bias correction to the gyros
GyrosBiasData gyrosBias;
GyrosBiasGet(&gyrosBias);
gyrosData.x += gyrosBias.x;
gyrosData.y += gyrosBias.y;
gyrosData.z += gyrosBias.z;
GyrosSet(&gyrosData);
BaroAltitudeData baroAltitude;
BaroAltitudeGet(&baroAltitude);
baroAltitude.Altitude = 1;
BaroAltitudeSet(&baroAltitude);
GPSPositionData gpsPosition;
GPSPositionGet(&gpsPosition);
gpsPosition.Latitude = 0;
gpsPosition.Longitude = 0;
gpsPosition.Altitude = 0;
GPSPositionSet(&gpsPosition);
// Because most crafts wont get enough information from gravity to zero yaw gyro, we try
// and make it average zero (weakly)
MagnetometerData mag;
mag.x = 400;
mag.y = 0;
mag.z = 800;
MagnetometerSet(&mag);
}
/**
* 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);
}
}
/**
* WARNING! This callback executes with critical flight control priority every
* time a gyroscope update happens do NOT put any time consuming calculations
* in this loop unless they really have to execute with every gyro update
*/
static void stabilizationInnerloopTask()
{
// watchdog and error handling
{
#ifdef PIOS_INCLUDE_WDG
PIOS_WDG_UpdateFlag(PIOS_WDG_STABILIZATION);
#endif
bool warn = false;
bool error = false;
bool crit = false;
// check if outer loop keeps executing
if (stabSettings.monitor.rateupdates > -64) {
stabSettings.monitor.rateupdates--;
}
if (stabSettings.monitor.rateupdates < -(2 * OUTERLOOP_SKIPCOUNT)) {
// warning if rate loop skipped more than 2 execution
warn = true;
}
if (stabSettings.monitor.rateupdates < -(4 * OUTERLOOP_SKIPCOUNT)) {
// critical if rate loop skipped more than 4 executions
crit = true;
}
// check if gyro keeps updating
if (stabSettings.monitor.gyroupdates < 1) {
// error if gyro didn't update at all!
error = true;
}
if (stabSettings.monitor.gyroupdates > 1) {
// warning if we missed a gyro update
warn = true;
}
if (stabSettings.monitor.gyroupdates > 3) {
// critical if we missed 3 gyro updates
crit = true;
}
stabSettings.monitor.gyroupdates = 0;
if (crit) {
AlarmsSet(SYSTEMALARMS_ALARM_STABILIZATION, SYSTEMALARMS_ALARM_CRITICAL);
} else if (error) {
AlarmsSet(SYSTEMALARMS_ALARM_STABILIZATION, SYSTEMALARMS_ALARM_ERROR);
} else if (warn) {
AlarmsSet(SYSTEMALARMS_ALARM_STABILIZATION, SYSTEMALARMS_ALARM_WARNING);
} else {
AlarmsClear(SYSTEMALARMS_ALARM_STABILIZATION);
}
}
RateDesiredData rateDesired;
ActuatorDesiredData actuator;
StabilizationStatusInnerLoopData enabled;
FlightStatusControlChainData cchain;
RateDesiredGet(&rateDesired);
ActuatorDesiredGet(&actuator);
StabilizationStatusInnerLoopGet(&enabled);
FlightStatusControlChainGet(&cchain);
float *rate = &rateDesired.Roll;
float *actuatorDesiredAxis = &actuator.Roll;
int t;
float dT;
dT = PIOS_DELTATIME_GetAverageSeconds(&timeval);
for (t = 0; t < AXES; t++) {
bool reinit = (cast_struct_to_array(enabled, enabled.Roll)[t] != previous_mode[t]);
previous_mode[t] = cast_struct_to_array(enabled, enabled.Roll)[t];
if (t < STABILIZATIONSTATUS_INNERLOOP_THRUST) {
if (reinit) {
stabSettings.innerPids[t].iAccumulator = 0;
}
switch (cast_struct_to_array(enabled, enabled.Roll)[t]) {
case STABILIZATIONSTATUS_INNERLOOP_VIRTUALFLYBAR:
stabilization_virtual_flybar(gyro_filtered[t], rate[t], &actuatorDesiredAxis[t], dT, reinit, t, &stabSettings.settings);
break;
case STABILIZATIONSTATUS_INNERLOOP_RELAYTUNING:
rate[t] = boundf(rate[t],
-cast_struct_to_array(stabSettings.stabBank.MaximumRate, stabSettings.stabBank.MaximumRate.Roll)[t],
cast_struct_to_array(stabSettings.stabBank.MaximumRate, stabSettings.stabBank.MaximumRate.Roll)[t]
);
stabilization_relay_rate(rate[t] - gyro_filtered[t], &actuatorDesiredAxis[t], t, reinit);
break;
case STABILIZATIONSTATUS_INNERLOOP_AXISLOCK:
if (fabsf(rate[t]) > stabSettings.settings.MaxAxisLockRate) {
// While getting strong commands act like rate mode
axis_lock_accum[t] = 0;
} else {
// For weaker commands or no command simply attitude lock (almost) on no gyro change
axis_lock_accum[t] += (rate[t] - gyro_filtered[t]) * dT;
axis_lock_accum[t] = boundf(axis_lock_accum[t], -stabSettings.settings.MaxAxisLock, stabSettings.settings.MaxAxisLock);
rate[t] = axis_lock_accum[t] * stabSettings.settings.AxisLockKp;
}
// IMPORTANT: deliberately no "break;" here, execution continues with regular RATE control loop to avoid code duplication!
// keep order as it is, RATE must follow!
case STABILIZATIONSTATUS_INNERLOOP_RATE:
// limit rate to maximum configured limits (once here instead of 5 times in outer loop)
rate[t] = boundf(rate[t],
-cast_struct_to_array(stabSettings.stabBank.MaximumRate, stabSettings.stabBank.MaximumRate.Roll)[t],
cast_struct_to_array(stabSettings.stabBank.MaximumRate, stabSettings.stabBank.MaximumRate.Roll)[t]
);
actuatorDesiredAxis[t] = pid_apply_setpoint(&stabSettings.innerPids[t], speedScaleFactor, rate[t], gyro_filtered[t], dT);
break;
case STABILIZATIONSTATUS_INNERLOOP_DIRECT:
default:
actuatorDesiredAxis[t] = rate[t];
break;
}
} else {
switch (cast_struct_to_array(enabled, enabled.Roll)[t]) {
case STABILIZATIONSTATUS_INNERLOOP_CRUISECONTROL:
actuatorDesiredAxis[t] = cruisecontrol_apply_factor(rate[t]);
break;
case STABILIZATIONSTATUS_INNERLOOP_DIRECT:
default:
actuatorDesiredAxis[t] = rate[t];
break;
}
}
actuatorDesiredAxis[t] = boundf(actuatorDesiredAxis[t], -1.0f, 1.0f);
}
actuator.UpdateTime = dT * 1000;
if (cchain.Stabilization == FLIGHTSTATUS_CONTROLCHAIN_TRUE) {
ActuatorDesiredSet(&actuator);
} else {
// Force all axes to reinitialize when engaged
for (t = 0; t < AXES; t++) {
previous_mode[t] = 255;
}
}
{
uint8_t armed;
FlightStatusArmedGet(&armed);
float throttleDesired;
ManualControlCommandThrottleGet(&throttleDesired);
if (armed != FLIGHTSTATUS_ARMED_ARMED ||
((stabSettings.settings.LowThrottleZeroIntegral == STABILIZATIONSETTINGS_LOWTHROTTLEZEROINTEGRAL_TRUE) && throttleDesired < 0)) {
// Force all axes to reinitialize when engaged
for (t = 0; t < AXES; t++) {
previous_mode[t] = 255;
}
}
}
PIOS_CALLBACKSCHEDULER_Schedule(callbackHandle, FAILSAFE_TIMEOUT_MS, CALLBACK_UPDATEMODE_LATER);
}
/**
* This method performs a simple simulation of a car
*
* It takes in the ActuatorDesired command to rotate the aircraft and performs
* a simple kinetic model where the throttle increases the energy and drag decreases
* it. Changing altitude moves energy from kinetic to potential.
*
* 1. Update attitude based on ActuatorDesired
* 2. Update position based on velocity
*/
static void simulateModelCar()
{
static double pos[3] = {0,0,0};
static double vel[3] = {0,0,0};
static double ned_accel[3] = {0,0,0};
static float q[4] = {1,0,0,0};
static float rpy[3] = {0,0,0}; // Low pass filtered actuator
static float baro_offset = 0.0f;
float Rbe[3][3];
const float ACTUATOR_ALPHA = 0.8;
const float MAX_THRUST = 9.81 * 0.5;
const float K_FRICTION = 0.2;
const float GPS_PERIOD = 0.1;
const float MAG_PERIOD = 1.0 / 75.0;
const float BARO_PERIOD = 1.0 / 20.0;
static uint32_t last_time;
float dT = (PIOS_DELAY_DiffuS(last_time) / 1e6);
if(dT < 1e-3)
dT = 2e-3;
last_time = PIOS_DELAY_GetRaw();
FlightStatusData flightStatus;
FlightStatusGet(&flightStatus);
ActuatorDesiredData actuatorDesired;
ActuatorDesiredGet(&actuatorDesired);
float thrust = (flightStatus.Armed == FLIGHTSTATUS_ARMED_ARMED) ? actuatorDesired.Throttle * MAX_THRUST : 0;
if (thrust < 0)
thrust = 0;
if (thrust != thrust)
thrust = 0;
// float control_scaling = thrust * thrustToDegs;
// // In rad/s
// rpy[0] = control_scaling * actuatorDesired.Roll * (1 - ACTUATOR_ALPHA) + rpy[0] * ACTUATOR_ALPHA;
// rpy[1] = control_scaling * actuatorDesired.Pitch * (1 - ACTUATOR_ALPHA) + rpy[1] * ACTUATOR_ALPHA;
// rpy[2] = control_scaling * actuatorDesired.Yaw * (1 - ACTUATOR_ALPHA) + rpy[2] * ACTUATOR_ALPHA;
//
// GyrosData gyrosData; // Skip get as we set all the fields
// gyrosData.x = rpy[0] * 180 / M_PI + rand_gauss();
// gyrosData.y = rpy[1] * 180 / M_PI + rand_gauss();
// gyrosData.z = rpy[2] * 180 / M_PI + rand_gauss();
/**** 1. Update attitude ****/
RateDesiredData rateDesired;
RateDesiredGet(&rateDesired);
// Need to get roll angle for easy cross coupling
AttitudeActualData attitudeActual;
AttitudeActualGet(&attitudeActual);
rpy[0] = 0; // cannot roll
rpy[1] = 0; // cannot pitch
rpy[2] = (flightStatus.Armed == FLIGHTSTATUS_ARMED_ARMED) * rateDesired.Yaw * (1 - ACTUATOR_ALPHA) + rpy[2] * ACTUATOR_ALPHA;
GyrosData gyrosData; // Skip get as we set all the fields
gyrosData.x = rpy[0] + rand_gauss();
gyrosData.y = rpy[1] + rand_gauss();
gyrosData.z = rpy[2] + rand_gauss();
GyrosSet(&gyrosData);
// Predict the attitude forward in time
float qdot[4];
qdot[0] = (-q[1] * rpy[0] - q[2] * rpy[1] - q[3] * rpy[2]) * dT * DEG2RAD / 2;
qdot[1] = (q[0] * rpy[0] - q[3] * rpy[1] + q[2] * rpy[2]) * dT * DEG2RAD / 2;
qdot[2] = (q[3] * rpy[0] + q[0] * rpy[1] - q[1] * rpy[2]) * dT * DEG2RAD / 2;
qdot[3] = (-q[2] * rpy[0] + q[1] * rpy[1] + q[0] * rpy[2]) * dT * DEG2RAD / 2;
// Take a time step
q[0] = q[0] + qdot[0];
q[1] = q[1] + qdot[1];
q[2] = q[2] + qdot[2];
q[3] = q[3] + qdot[3];
float qmag = sqrtf(q[0]*q[0] + q[1]*q[1] + q[2]*q[2] + q[3]*q[3]);
q[0] = q[0] / qmag;
q[1] = q[1] / qmag;
q[2] = q[2] / qmag;
q[3] = q[3] / qmag;
if(overideAttitude){
AttitudeActualData attitudeActual;
AttitudeActualGet(&attitudeActual);
attitudeActual.q1 = q[0];
attitudeActual.q2 = q[1];
attitudeActual.q3 = q[2];
attitudeActual.q4 = q[3];
AttitudeActualSet(&attitudeActual);
}
/**** 2. Update position based on velocity ****/
// Rbe takes a vector from body to earth. If we take (1,0,0)^T through this and then dot with airspeed
// we get forward airspeed
Quaternion2R(q,Rbe);
double groundspeed[3] = {vel[0], vel[1], vel[2] };
double forwardSpeed = Rbe[0][0] * groundspeed[0] + Rbe[0][1] * groundspeed[1] + Rbe[0][2] * groundspeed[2];
double sidewaysSpeed = Rbe[1][0] * groundspeed[0] + Rbe[1][1] * groundspeed[1] + Rbe[1][2] * groundspeed[2];
/* Compute aerodynamic forces in body referenced frame. Later use more sophisticated equations */
/* TODO: This should become more accurate. Use the force equations to calculate lift from the */
/* various surfaces based on AoA and airspeed. From that compute torques and forces. For later */
double forces[3]; // X, Y, Z
forces[0] = thrust - forwardSpeed * K_FRICTION; // Friction is applied in all directions in NED
forces[1] = 0 - sidewaysSpeed * K_FRICTION * 100; // No side slip
forces[2] = 0;
// Negate force[2] as NED defines down as possitive, aircraft convention is Z up is positive (?)
ned_accel[0] = forces[0] * Rbe[0][0] + forces[1] * Rbe[1][0] - forces[2] * Rbe[2][0];
ned_accel[1] = forces[0] * Rbe[0][1] + forces[1] * Rbe[1][1] - forces[2] * Rbe[2][1];
ned_accel[2] = 0;
// Apply acceleration based on velocity
ned_accel[0] -= K_FRICTION * (vel[0]);
ned_accel[1] -= K_FRICTION * (vel[1]);
// Predict the velocity forward in time
vel[0] = vel[0] + ned_accel[0] * dT;
vel[1] = vel[1] + ned_accel[1] * dT;
vel[2] = vel[2] + ned_accel[2] * dT;
// Predict the position forward in time
pos[0] = pos[0] + vel[0] * dT;
pos[1] = pos[1] + vel[1] * dT;
pos[2] = pos[2] + vel[2] * dT;
// Simulate hitting ground
if(pos[2] > 0) {
pos[2] = 0;
vel[2] = 0;
ned_accel[2] = 0;
}
// Sensor feels gravity (when not acceleration in ned frame e.g. ned_accel[2] = 0)
ned_accel[2] -= GRAVITY;
// Transform the accels back in to body frame
AccelsData accelsData; // Skip get as we set all the fields
accelsData.x = ned_accel[0] * Rbe[0][0] + ned_accel[1] * Rbe[0][1] + ned_accel[2] * Rbe[0][2] + accel_bias[0];
accelsData.y = ned_accel[0] * Rbe[1][0] + ned_accel[1] * Rbe[1][1] + ned_accel[2] * Rbe[1][2] + accel_bias[1];
accelsData.z = ned_accel[0] * Rbe[2][0] + ned_accel[1] * Rbe[2][1] + ned_accel[2] * Rbe[2][2] + accel_bias[2];
accelsData.temperature = 30;
AccelsSet(&accelsData);
if(baro_offset == 0) {
// Hacky initialization
baro_offset = 50;// * rand_gauss();
} else {
// Very small drift process
baro_offset += rand_gauss() / 100;
}
// Update baro periodically
static uint32_t last_baro_time = 0;
if(PIOS_DELAY_DiffuS(last_baro_time) / 1.0e6 > BARO_PERIOD) {
BaroAltitudeData baroAltitude;
BaroAltitudeGet(&baroAltitude);
baroAltitude.Altitude = -pos[2] + baro_offset;
BaroAltitudeSet(&baroAltitude);
last_baro_time = PIOS_DELAY_GetRaw();
}
HomeLocationData homeLocation;
HomeLocationGet(&homeLocation);
static float gps_vel_drift[3] = {0,0,0};
gps_vel_drift[0] = gps_vel_drift[0] * 0.65 + rand_gauss() / 5.0;
gps_vel_drift[1] = gps_vel_drift[1] * 0.65 + rand_gauss() / 5.0;
gps_vel_drift[2] = gps_vel_drift[2] * 0.65 + rand_gauss() / 5.0;
// Update GPS periodically
static uint32_t last_gps_time = 0;
if(PIOS_DELAY_DiffuS(last_gps_time) / 1.0e6 > GPS_PERIOD) {
// Use double precision here as simulating what GPS produces
double T[3];
T[0] = homeLocation.Altitude+6.378137E6f * DEG2RAD;
T[1] = cosf(homeLocation.Latitude / 10e6 * DEG2RAD)*(homeLocation.Altitude+6.378137E6) * DEG2RAD;
T[2] = -1.0;
static float gps_drift[3] = {0,0,0};
gps_drift[0] = gps_drift[0] * 0.95 + rand_gauss() / 10.0;
gps_drift[1] = gps_drift[1] * 0.95 + rand_gauss() / 10.0;
gps_drift[2] = gps_drift[2] * 0.95 + rand_gauss() / 10.0;
GPSPositionData gpsPosition;
GPSPositionGet(&gpsPosition);
gpsPosition.Latitude = homeLocation.Latitude + ((pos[0] + gps_drift[0]) / T[0] * 10.0e6);
gpsPosition.Longitude = homeLocation.Longitude + ((pos[1] + gps_drift[1])/ T[1] * 10.0e6);
gpsPosition.Altitude = homeLocation.Altitude + ((pos[2] + gps_drift[2]) / T[2]);
gpsPosition.Groundspeed = sqrtf(pow(vel[0] + gps_vel_drift[0],2) + pow(vel[1] + gps_vel_drift[1],2));
gpsPosition.Heading = 180 / M_PI * atan2f(vel[1] + gps_vel_drift[1],vel[0] + gps_vel_drift[0]);
gpsPosition.Satellites = 7;
gpsPosition.PDOP = 1;
GPSPositionSet(&gpsPosition);
last_gps_time = PIOS_DELAY_GetRaw();
}
// Update GPS Velocity measurements
static uint32_t last_gps_vel_time = 1000; // Delay by a millisecond
if(PIOS_DELAY_DiffuS(last_gps_vel_time) / 1.0e6 > GPS_PERIOD) {
GPSVelocityData gpsVelocity;
GPSVelocityGet(&gpsVelocity);
gpsVelocity.North = vel[0] + gps_vel_drift[0];
gpsVelocity.East = vel[1] + gps_vel_drift[1];
gpsVelocity.Down = vel[2] + gps_vel_drift[2];
GPSVelocitySet(&gpsVelocity);
last_gps_vel_time = PIOS_DELAY_GetRaw();
}
// Update mag periodically
static uint32_t last_mag_time = 0;
if(PIOS_DELAY_DiffuS(last_mag_time) / 1.0e6 > MAG_PERIOD) {
MagnetometerData mag;
mag.x = 100+homeLocation.Be[0] * Rbe[0][0] + homeLocation.Be[1] * Rbe[0][1] + homeLocation.Be[2] * Rbe[0][2];
mag.y = 100+homeLocation.Be[0] * Rbe[1][0] + homeLocation.Be[1] * Rbe[1][1] + homeLocation.Be[2] * Rbe[1][2];
mag.z = 100+homeLocation.Be[0] * Rbe[2][0] + homeLocation.Be[1] * Rbe[2][1] + homeLocation.Be[2] * Rbe[2][2];
magOffsetEstimation(&mag);
MagnetometerSet(&mag);
last_mag_time = PIOS_DELAY_GetRaw();
}
AttitudeSimulatedData attitudeSimulated;
AttitudeSimulatedGet(&attitudeSimulated);
attitudeSimulated.q1 = q[0];
attitudeSimulated.q2 = q[1];
attitudeSimulated.q3 = q[2];
attitudeSimulated.q4 = q[3];
Quaternion2RPY(q,&attitudeSimulated.Roll);
attitudeSimulated.Position[0] = pos[0];
attitudeSimulated.Position[1] = pos[1];
attitudeSimulated.Position[2] = pos[2];
attitudeSimulated.Velocity[0] = vel[0];
attitudeSimulated.Velocity[1] = vel[1];
attitudeSimulated.Velocity[2] = vel[2];
AttitudeSimulatedSet(&attitudeSimulated);
}
static void simulateModelQuadcopter()
{
static double pos[3] = {0,0,0};
static double vel[3] = {0,0,0};
static double ned_accel[3] = {0,0,0};
static float q[4] = {1,0,0,0};
static float rpy[3] = {0,0,0}; // Low pass filtered actuator
static float baro_offset = 0.0f;
static float temperature = 20;
float Rbe[3][3];
const float ACTUATOR_ALPHA = 0.8;
const float MAX_THRUST = GRAVITY * 2;
const float K_FRICTION = 1;
const float GPS_PERIOD = 0.1;
const float MAG_PERIOD = 1.0 / 75.0;
const float BARO_PERIOD = 1.0 / 20.0;
static uint32_t last_time;
float dT = (PIOS_DELAY_DiffuS(last_time) / 1e6);
if(dT < 1e-3)
dT = 2e-3;
last_time = PIOS_DELAY_GetRaw();
FlightStatusData flightStatus;
FlightStatusGet(&flightStatus);
ActuatorDesiredData actuatorDesired;
ActuatorDesiredGet(&actuatorDesired);
float thrust = (flightStatus.Armed == FLIGHTSTATUS_ARMED_ARMED) ? actuatorDesired.Throttle * MAX_THRUST : 0;
if (thrust < 0)
thrust = 0;
if (thrust != thrust)
thrust = 0;
// float control_scaling = thrust * thrustToDegs;
// // In rad/s
// rpy[0] = control_scaling * actuatorDesired.Roll * (1 - ACTUATOR_ALPHA) + rpy[0] * ACTUATOR_ALPHA;
// rpy[1] = control_scaling * actuatorDesired.Pitch * (1 - ACTUATOR_ALPHA) + rpy[1] * ACTUATOR_ALPHA;
// rpy[2] = control_scaling * actuatorDesired.Yaw * (1 - ACTUATOR_ALPHA) + rpy[2] * ACTUATOR_ALPHA;
//
// GyrosData gyrosData; // Skip get as we set all the fields
// gyrosData.x = rpy[0] * 180 / M_PI + rand_gauss();
// gyrosData.y = rpy[1] * 180 / M_PI + rand_gauss();
// gyrosData.z = rpy[2] * 180 / M_PI + rand_gauss();
RateDesiredData rateDesired;
RateDesiredGet(&rateDesired);
rpy[0] = (flightStatus.Armed == FLIGHTSTATUS_ARMED_ARMED) * rateDesired.Roll * (1 - ACTUATOR_ALPHA) + rpy[0] * ACTUATOR_ALPHA;
rpy[1] = (flightStatus.Armed == FLIGHTSTATUS_ARMED_ARMED) * rateDesired.Pitch * (1 - ACTUATOR_ALPHA) + rpy[1] * ACTUATOR_ALPHA;
rpy[2] = (flightStatus.Armed == FLIGHTSTATUS_ARMED_ARMED) * rateDesired.Yaw * (1 - ACTUATOR_ALPHA) + rpy[2] * ACTUATOR_ALPHA;
temperature = 20;
GyrosData gyrosData; // Skip get as we set all the fields
gyrosData.x = rpy[0] + rand_gauss() + (temperature - 20) * 1 + powf(temperature - 20,2) * 0.11; // - powf(temperature - 20,3) * 0.05;;
gyrosData.y = rpy[1] + rand_gauss() + (temperature - 20) * 1 + powf(temperature - 20,2) * 0.11;;
gyrosData.z = rpy[2] + rand_gauss() + (temperature - 20) * 1 + powf(temperature - 20,2) * 0.11;;
gyrosData.temperature = temperature;
GyrosSet(&gyrosData);
// Predict the attitude forward in time
float qdot[4];
qdot[0] = (-q[1] * rpy[0] - q[2] * rpy[1] - q[3] * rpy[2]) * dT * DEG2RAD / 2;
qdot[1] = (q[0] * rpy[0] - q[3] * rpy[1] + q[2] * rpy[2]) * dT * DEG2RAD / 2;
qdot[2] = (q[3] * rpy[0] + q[0] * rpy[1] - q[1] * rpy[2]) * dT * DEG2RAD / 2;
qdot[3] = (-q[2] * rpy[0] + q[1] * rpy[1] + q[0] * rpy[2]) * dT * DEG2RAD / 2;
// Take a time step
q[0] = q[0] + qdot[0];
q[1] = q[1] + qdot[1];
q[2] = q[2] + qdot[2];
q[3] = q[3] + qdot[3];
float qmag = sqrtf(q[0]*q[0] + q[1]*q[1] + q[2]*q[2] + q[3]*q[3]);
q[0] = q[0] / qmag;
q[1] = q[1] / qmag;
q[2] = q[2] / qmag;
q[3] = q[3] / qmag;
if(overideAttitude){
AttitudeActualData attitudeActual;
AttitudeActualGet(&attitudeActual);
attitudeActual.q1 = q[0];
attitudeActual.q2 = q[1];
attitudeActual.q3 = q[2];
attitudeActual.q4 = q[3];
AttitudeActualSet(&attitudeActual);
}
static float wind[3] = {0,0,0};
wind[0] = wind[0] * 0.95 + rand_gauss() / 10.0;
wind[1] = wind[1] * 0.95 + rand_gauss() / 10.0;
wind[2] = wind[2] * 0.95 + rand_gauss() / 10.0;
Quaternion2R(q,Rbe);
// Make thrust negative as down is positive
ned_accel[0] = -thrust * Rbe[2][0];
ned_accel[1] = -thrust * Rbe[2][1];
// Gravity causes acceleration of 9.81 in the down direction
ned_accel[2] = -thrust * Rbe[2][2] + GRAVITY;
// Apply acceleration based on velocity
ned_accel[0] -= K_FRICTION * (vel[0] - wind[0]);
ned_accel[1] -= K_FRICTION * (vel[1] - wind[1]);
ned_accel[2] -= K_FRICTION * (vel[2] - wind[2]);
// Predict the velocity forward in time
vel[0] = vel[0] + ned_accel[0] * dT;
vel[1] = vel[1] + ned_accel[1] * dT;
vel[2] = vel[2] + ned_accel[2] * dT;
// Predict the position forward in time
pos[0] = pos[0] + vel[0] * dT;
pos[1] = pos[1] + vel[1] * dT;
pos[2] = pos[2] + vel[2] * dT;
// Simulate hitting ground
if(pos[2] > 0) {
pos[2] = 0;
vel[2] = 0;
ned_accel[2] = 0;
}
// Sensor feels gravity (when not acceleration in ned frame e.g. ned_accel[2] = 0)
ned_accel[2] -= 9.81;
// Transform the accels back in to body frame
AccelsData accelsData; // Skip get as we set all the fields
accelsData.x = ned_accel[0] * Rbe[0][0] + ned_accel[1] * Rbe[0][1] + ned_accel[2] * Rbe[0][2] + accel_bias[0];
accelsData.y = ned_accel[0] * Rbe[1][0] + ned_accel[1] * Rbe[1][1] + ned_accel[2] * Rbe[1][2] + accel_bias[1];
accelsData.z = ned_accel[0] * Rbe[2][0] + ned_accel[1] * Rbe[2][1] + ned_accel[2] * Rbe[2][2] + accel_bias[2];
accelsData.temperature = 30;
AccelsSet(&accelsData);
if(baro_offset == 0) {
// Hacky initialization
baro_offset = 50;// * rand_gauss();
} else {
// Very small drift process
baro_offset += rand_gauss() / 100;
}
// Update baro periodically
static uint32_t last_baro_time = 0;
if(PIOS_DELAY_DiffuS(last_baro_time) / 1.0e6 > BARO_PERIOD) {
BaroAltitudeData baroAltitude;
BaroAltitudeGet(&baroAltitude);
baroAltitude.Altitude = -pos[2] + baro_offset;
BaroAltitudeSet(&baroAltitude);
last_baro_time = PIOS_DELAY_GetRaw();
}
HomeLocationData homeLocation;
HomeLocationGet(&homeLocation);
static float gps_vel_drift[3] = {0,0,0};
gps_vel_drift[0] = gps_vel_drift[0] * 0.65 + rand_gauss() / 5.0;
gps_vel_drift[1] = gps_vel_drift[1] * 0.65 + rand_gauss() / 5.0;
gps_vel_drift[2] = gps_vel_drift[2] * 0.65 + rand_gauss() / 5.0;
// Update GPS periodically
static uint32_t last_gps_time = 0;
if(PIOS_DELAY_DiffuS(last_gps_time) / 1.0e6 > GPS_PERIOD) {
// Use double precision here as simulating what GPS produces
double T[3];
T[0] = homeLocation.Altitude+6.378137E6f * DEG2RAD;
T[1] = cosf(homeLocation.Latitude / 10e6 * DEG2RAD)*(homeLocation.Altitude+6.378137E6) * DEG2RAD;
T[2] = -1.0;
static float gps_drift[3] = {0,0,0};
gps_drift[0] = gps_drift[0] * 0.95 + rand_gauss() / 10.0;
gps_drift[1] = gps_drift[1] * 0.95 + rand_gauss() / 10.0;
gps_drift[2] = gps_drift[2] * 0.95 + rand_gauss() / 10.0;
GPSPositionData gpsPosition;
GPSPositionGet(&gpsPosition);
gpsPosition.Latitude = homeLocation.Latitude + ((pos[0] + gps_drift[0]) / T[0] * 10.0e6);
gpsPosition.Longitude = homeLocation.Longitude + ((pos[1] + gps_drift[1])/ T[1] * 10.0e6);
gpsPosition.Altitude = homeLocation.Altitude + ((pos[2] + gps_drift[2]) / T[2]);
gpsPosition.Groundspeed = sqrtf(pow(vel[0] + gps_vel_drift[0],2) + pow(vel[1] + gps_vel_drift[1],2));
gpsPosition.Heading = 180 / M_PI * atan2f(vel[1] + gps_vel_drift[1],vel[0] + gps_vel_drift[0]);
gpsPosition.Satellites = 7;
gpsPosition.PDOP = 1;
gpsPosition.Status = GPSPOSITION_STATUS_FIX3D;
GPSPositionSet(&gpsPosition);
last_gps_time = PIOS_DELAY_GetRaw();
}
// Update GPS Velocity measurements
static uint32_t last_gps_vel_time = 1000; // Delay by a millisecond
if(PIOS_DELAY_DiffuS(last_gps_vel_time) / 1.0e6 > GPS_PERIOD) {
GPSVelocityData gpsVelocity;
GPSVelocityGet(&gpsVelocity);
gpsVelocity.North = vel[0] + gps_vel_drift[0];
gpsVelocity.East = vel[1] + gps_vel_drift[1];
gpsVelocity.Down = vel[2] + gps_vel_drift[2];
GPSVelocitySet(&gpsVelocity);
last_gps_vel_time = PIOS_DELAY_GetRaw();
}
// Update mag periodically
static uint32_t last_mag_time = 0;
if(PIOS_DELAY_DiffuS(last_mag_time) / 1.0e6 > MAG_PERIOD) {
MagnetometerData mag;
mag.x = homeLocation.Be[0] * Rbe[0][0] + homeLocation.Be[1] * Rbe[0][1] + homeLocation.Be[2] * Rbe[0][2];
mag.y = homeLocation.Be[0] * Rbe[1][0] + homeLocation.Be[1] * Rbe[1][1] + homeLocation.Be[2] * Rbe[1][2];
mag.z = homeLocation.Be[0] * Rbe[2][0] + homeLocation.Be[1] * Rbe[2][1] + homeLocation.Be[2] * Rbe[2][2];
// Run the offset compensation algorithm from the firmware
magOffsetEstimation(&mag);
MagnetometerSet(&mag);
last_mag_time = PIOS_DELAY_GetRaw();
}
AttitudeSimulatedData attitudeSimulated;
AttitudeSimulatedGet(&attitudeSimulated);
attitudeSimulated.q1 = q[0];
attitudeSimulated.q2 = q[1];
attitudeSimulated.q3 = q[2];
attitudeSimulated.q4 = q[3];
Quaternion2RPY(q,&attitudeSimulated.Roll);
attitudeSimulated.Position[0] = pos[0];
attitudeSimulated.Position[1] = pos[1];
attitudeSimulated.Position[2] = pos[2];
attitudeSimulated.Velocity[0] = vel[0];
attitudeSimulated.Velocity[1] = vel[1];
attitudeSimulated.Velocity[2] = vel[2];
AttitudeSimulatedSet(&attitudeSimulated);
}
/**
* 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);
}
}
