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); } }