/** ****************************************************************************** * @addtogroup OpenPilotModules OpenPilot Modules * @{ * @addtogroup Attitude Copter Control Attitude Estimation * @brief Acquires sensor data and computes attitude estimate * Specifically updates the the @ref AttitudeActual "AttitudeActual" and @ref AttitudeRaw "AttitudeRaw" settings objects * @{ * * @file attitude.c * @author The OpenPilot Team, http://www.openpilot.org Copyright (C) 2010. * @brief Module to handle all comms to the AHRS on a periodic basis. * * @see The GNU Public License (GPL) Version 3 * ******************************************************************************/ /* * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ /** * Input objects: None, takes sensor data via pios * Output objects: @ref AttitudeRaw @ref AttitudeActual * * This module computes an attitude estimate from the sensor data * * The module executes in its own thread. * * UAVObjects are automatically generated by the UAVObjectGenerator from * the object definition XML file. * * Modules have no API, all communication to other modules is done through UAVObjects. * However modules may use the API exposed by shared libraries. * See the OpenPilot wiki for more details. * http://www.openpilot.org/OpenPilot_Application_Architecture * */ #include "pios.h" #include "attitude.h" #include "gyros.h" #include "accels.h" #include "attitudeactual.h" #include "attitudesettings.h" #include "flightstatus.h" #include "manualcontrolcommand.h" #include "CoordinateConversions.h" #include // Private constants #define STACK_SIZE_BYTES 540 #define TASK_PRIORITY (tskIDLE_PRIORITY+3) #define SENSOR_PERIOD 4 #define UPDATE_RATE 25.0f #define GYRO_NEUTRAL 1665 #define PI_MOD(x) (fmod(x + M_PI, M_PI * 2) - M_PI) // Private types // Private variables static xTaskHandle taskHandle; // Private functions static void AttitudeTask(void *parameters); static float gyro_correct_int[3] = {0,0,0}; static xQueueHandle gyro_queue; static int32_t updateSensors(AccelsData *, GyrosData *); static int32_t updateSensorsCC3D(AccelsData * accelsData, GyrosData * gyrosData); static void updateAttitude(AccelsData *, GyrosData *); static void settingsUpdatedCb(UAVObjEvent * objEv); static float accelKi = 0; static float accelKp = 0; static float yawBiasRate = 0; static float gyroGain = 0.42; static int16_t accelbias[3]; static float q[4] = {1,0,0,0}; static float R[3][3]; static int8_t rotate = 0; static bool zero_during_arming = false; static bool bias_correct_gyro = true; // For running trim flights static volatile bool trim_requested = false; static volatile int32_t trim_accels[3]; static volatile int32_t trim_samples; int32_t const MAX_TRIM_FLIGHT_SAMPLES = 65535; #define GRAV 9.81f #define ACCEL_SCALE (GRAV * 0.004f) /* 0.004f is gravity / LSB */ /** * Initialise the module, called on startup * \returns 0 on success or -1 if initialisation failed */ int32_t AttitudeStart(void) { // Start main task xTaskCreate(AttitudeTask, (signed char *)"Attitude", STACK_SIZE_BYTES/4, NULL, TASK_PRIORITY, &taskHandle); TaskMonitorAdd(TASKINFO_RUNNING_ATTITUDE, taskHandle); PIOS_WDG_RegisterFlag(PIOS_WDG_ATTITUDE); return 0; } /** * Initialise the module, called on startup * \returns 0 on success or -1 if initialisation failed */ int32_t AttitudeInitialize(void) { AttitudeActualInitialize(); AttitudeSettingsInitialize(); AccelsInitialize(); GyrosInitialize(); // Initialize quaternion AttitudeActualData attitude; AttitudeActualGet(&attitude); attitude.q1 = 1; attitude.q2 = 0; attitude.q3 = 0; attitude.q4 = 0; AttitudeActualSet(&attitude); // Cannot trust the values to init right above if BL runs gyro_correct_int[0] = 0; gyro_correct_int[1] = 0; gyro_correct_int[2] = 0; q[0] = 1; q[1] = 0; q[2] = 0; q[3] = 0; for(uint8_t i = 0; i < 3; i++) for(uint8_t j = 0; j < 3; j++) R[i][j] = 0; trim_requested = false; AttitudeSettingsConnectCallback(&settingsUpdatedCb); return 0; } MODULE_INITCALL(AttitudeInitialize, AttitudeStart) /** * Module thread, should not return. */ int32_t accel_test; int32_t gyro_test; static void AttitudeTask(void *parameters) { uint8_t init = 0; AlarmsClear(SYSTEMALARMS_ALARM_ATTITUDE); // Set critical error and wait until the accel is producing data while(PIOS_ADXL345_FifoElements() == 0) { AlarmsSet(SYSTEMALARMS_ALARM_ATTITUDE, SYSTEMALARMS_ALARM_CRITICAL); PIOS_WDG_UpdateFlag(PIOS_WDG_ATTITUDE); } const struct pios_board_info * bdinfo = &pios_board_info_blob; bool cc3d = bdinfo->board_rev == 0x02; if(cc3d) { #if defined(PIOS_INCLUDE_MPU6000) gyro_test = PIOS_MPU6000_Test(); #endif } else { #if defined(PIOS_INCLUDE_ADXL345) accel_test = PIOS_ADXL345_Test(); #endif #if defined(PIOS_INCLUDE_ADC) // Create queue for passing gyro data, allow 2 back samples in case gyro_queue = xQueueCreate(1, sizeof(float) * 4); PIOS_Assert(gyro_queue != NULL); PIOS_ADC_SetQueue(gyro_queue); PIOS_ADC_Config((PIOS_ADC_RATE / 1000.0f) * UPDATE_RATE); #endif } // Force settings update to make sure rotation loaded settingsUpdatedCb(AttitudeSettingsHandle()); // Main task loop while (1) { FlightStatusData flightStatus; FlightStatusGet(&flightStatus); if((xTaskGetTickCount() < 7000) && (xTaskGetTickCount() > 1000)) { // For first 7 seconds use accels to get gyro bias accelKp = 1; accelKi = 0.9; yawBiasRate = 0.23; init = 0; } else if (zero_during_arming && (flightStatus.Armed == FLIGHTSTATUS_ARMED_ARMING)) { accelKp = 1; accelKi = 0.9; yawBiasRate = 0.23; init = 0; } else if (init == 0) { // Reload settings (all the rates) AttitudeSettingsAccelKiGet(&accelKi); AttitudeSettingsAccelKpGet(&accelKp); AttitudeSettingsYawBiasRateGet(&yawBiasRate); init = 1; } PIOS_WDG_UpdateFlag(PIOS_WDG_ATTITUDE); AccelsData accels; GyrosData gyros; int32_t retval = 0; if (cc3d) retval = updateSensorsCC3D(&accels, &gyros); else retval = updateSensors(&accels, &gyros); // Only update attitude when sensor data is good if (retval != 0) AlarmsSet(SYSTEMALARMS_ALARM_ATTITUDE, SYSTEMALARMS_ALARM_ERROR); else { // Do not update attitude data in simulation mode if (!AttitudeActualReadOnly()) updateAttitude(&accels, &gyros); AlarmsClear(SYSTEMALARMS_ALARM_ATTITUDE); } } } float gyros_passed[3]; /** * Get an update from the sensors * @param[in] attitudeRaw Populate the UAVO instead of saving right here * @return 0 if successfull, -1 if not */ static int32_t updateSensors(AccelsData * accels, GyrosData * gyros) { struct pios_adxl345_data accel_data; float gyro[4]; // Only wait the time for two nominal updates before setting an alarm if(xQueueReceive(gyro_queue, (void * const) gyro, UPDATE_RATE * 2) == errQUEUE_EMPTY) { AlarmsSet(SYSTEMALARMS_ALARM_ATTITUDE, SYSTEMALARMS_ALARM_ERROR); return -1; } // Do not read raw sensor data in simulation mode if (GyrosReadOnly() || AccelsReadOnly()) return 0; // No accel data available if(PIOS_ADXL345_FifoElements() == 0) return -1; // First sample is temperature gyros->x = -(gyro[1] - GYRO_NEUTRAL) * gyroGain; gyros->y = (gyro[2] - GYRO_NEUTRAL) * gyroGain; gyros->z = -(gyro[3] - GYRO_NEUTRAL) * gyroGain; int32_t x = 0; int32_t y = 0; int32_t z = 0; uint8_t i = 0; uint8_t samples_remaining; do { i++; samples_remaining = PIOS_ADXL345_Read(&accel_data); x += accel_data.x; y += -accel_data.y; z += -accel_data.z; } while ( (i < 32) && (samples_remaining > 0) ); gyros->temperature = samples_remaining; float accel[3] = {(float) x / i, (float) y / i, (float) z / i}; if(rotate) { // TODO: rotate sensors too so stabilization is well behaved float vec_out[3]; rot_mult(R, accel, vec_out); accels->x = vec_out[0]; accels->y = vec_out[1]; accels->z = vec_out[2]; rot_mult(R, &gyros->x, vec_out); gyros->x = vec_out[0]; gyros->y = vec_out[1]; gyros->z = vec_out[2]; } else { accels->x = accel[0]; accels->y = accel[1]; accels->z = accel[2]; } if (trim_requested) { if (trim_samples >= MAX_TRIM_FLIGHT_SAMPLES) { trim_requested = false; } else { uint8_t armed; float throttle; FlightStatusArmedGet(&armed); ManualControlCommandThrottleGet(&throttle); // Until flight status indicates airborne if ((armed == FLIGHTSTATUS_ARMED_ARMED) && (throttle > 0)) { trim_samples++; // Store the digitally scaled version since that is what we use for bias trim_accels[0] += accels->x; trim_accels[1] += accels->y; trim_accels[2] += accels->z; } } } // Scale accels and correct bias accels->x = (accels->x - accelbias[0]) * ACCEL_SCALE; accels->y = (accels->y - accelbias[1]) * ACCEL_SCALE; accels->z = (accels->z - accelbias[2]) * ACCEL_SCALE; if(bias_correct_gyro) { // Applying integral component here so it can be seen on the gyros and correct bias gyros->x += gyro_correct_int[0]; gyros->y += gyro_correct_int[1]; gyros->z += gyro_correct_int[2]; } // Because most crafts wont get enough information from gravity to zero yaw gyro, we try // and make it average zero (weakly) gyro_correct_int[2] += - gyros->z * yawBiasRate; GyrosSet(gyros); AccelsSet(accels); return 0; } /** * Get an update from the sensors * @param[in] attitudeRaw Populate the UAVO instead of saving right here * @return 0 if successfull, -1 if not */ struct pios_mpu6000_data mpu6000_data; static int32_t updateSensorsCC3D(AccelsData * accelsData, GyrosData * gyrosData) { float accels[3], gyros[3]; #if defined(PIOS_INCLUDE_MPU6000) xQueueHandle queue = PIOS_MPU6000_GetQueue(); if(xQueueReceive(queue, (void *) &mpu6000_data, SENSOR_PERIOD) == errQUEUE_EMPTY) return -1; // Error, no data // Do not read raw sensor data in simulation mode if (GyrosReadOnly() || AccelsReadOnly()) return 0; gyros[0] = -mpu6000_data.gyro_y * PIOS_MPU6000_GetScale(); gyros[1] = -mpu6000_data.gyro_x * PIOS_MPU6000_GetScale(); gyros[2] = -mpu6000_data.gyro_z * PIOS_MPU6000_GetScale(); accels[0] = -mpu6000_data.accel_y * PIOS_MPU6000_GetAccelScale(); accels[1] = -mpu6000_data.accel_x * PIOS_MPU6000_GetAccelScale(); accels[2] = -mpu6000_data.accel_z * PIOS_MPU6000_GetAccelScale(); gyrosData->temperature = 35.0f + ((float) mpu6000_data.temperature + 512.0f) / 340.0f; accelsData->temperature = 35.0f + ((float) mpu6000_data.temperature + 512.0f) / 340.0f; #endif if(rotate) { // TODO: rotate sensors too so stabilization is well behaved float vec_out[3]; rot_mult(R, accels, vec_out); accels[0] = vec_out[0]; accels[1] = vec_out[1]; accels[2] = vec_out[2]; rot_mult(R, gyros, vec_out); gyros[0] = vec_out[0]; gyros[1] = vec_out[1]; gyros[2] = vec_out[2]; } accelsData->x = accels[0] - accelbias[0] * ACCEL_SCALE; // Applying arbitrary scale here to match CC v1 accelsData->y = accels[1] - accelbias[1] * ACCEL_SCALE; accelsData->z = accels[2] - accelbias[2] * ACCEL_SCALE; AccelsSet(&accelsData); gyrosData->x = gyros[0]; gyrosData->y = gyros[1]; gyrosData->z = gyros[2]; if(bias_correct_gyro) { // Applying integral component here so it can be seen on the gyros and correct bias gyrosData->x += gyro_correct_int[0]; gyrosData->y += gyro_correct_int[1]; gyrosData->z += gyro_correct_int[2]; } // Because most crafts wont get enough information from gravity to zero yaw gyro, we try // and make it average zero (weakly) gyro_correct_int[2] += - gyrosData->z * yawBiasRate; GyrosSet(gyrosData); AccelsSet(accelsData); return 0; } static void updateAttitude(AccelsData * accelsData, GyrosData * gyrosData) { float dT; portTickType thisSysTime = xTaskGetTickCount(); static portTickType lastSysTime = 0; dT = (thisSysTime == lastSysTime) ? 0.001 : (portMAX_DELAY & (thisSysTime - lastSysTime)) / portTICK_RATE_MS / 1000.0f; lastSysTime = thisSysTime; // Bad practice to assume structure order, but saves memory float * gyros = &gyrosData->x; float * accels = &accelsData->x; float grot[3]; float accel_err[3]; // Rotate gravity to body frame and cross with accels grot[0] = -(2 * (q[1] * q[3] - q[0] * q[2])); grot[1] = -(2 * (q[2] * q[3] + q[0] * q[1])); grot[2] = -(q[0] * q[0] - q[1]*q[1] - q[2]*q[2] + q[3]*q[3]); CrossProduct((const float *) accels, (const float *) grot, accel_err); // Account for accel magnitude float accel_mag = sqrtf(accels[0]*accels[0] + accels[1]*accels[1] + accels[2]*accels[2]); if(accel_mag < 1.0e-3f) return; accel_err[0] /= accel_mag; accel_err[1] /= accel_mag; accel_err[2] /= accel_mag; // Accumulate integral of error. Scale here so that units are (deg/s) but Ki has units of s gyro_correct_int[0] += accel_err[0] * accelKi; gyro_correct_int[1] += accel_err[1] * accelKi; //gyro_correct_int[2] += accel_err[2] * accelKi; // Correct rates based on error, integral component dealt with in updateSensors gyros[0] += accel_err[0] * accelKp / dT; gyros[1] += accel_err[1] * accelKp / dT; gyros[2] += accel_err[2] * accelKp / dT; { // scoping variables to save memory // Work out time derivative from INSAlgo writeup // Also accounts for the fact that gyros are in deg/s float qdot[4]; qdot[0] = (-q[1] * gyros[0] - q[2] * gyros[1] - q[3] * gyros[2]) * dT * M_PI / 180 / 2; qdot[1] = (q[0] * gyros[0] - q[3] * gyros[1] + q[2] * gyros[2]) * dT * M_PI / 180 / 2; qdot[2] = (q[3] * gyros[0] + q[0] * gyros[1] - q[1] * gyros[2]) * dT * M_PI / 180 / 2; qdot[3] = (-q[2] * gyros[0] + q[1] * gyros[1] + q[0] * gyros[2]) * dT * M_PI / 180 / 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]; if(q[0] < 0) { q[0] = -q[0]; q[1] = -q[1]; q[2] = -q[2]; q[3] = -q[3]; } } // Renomalize 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 quaternion has become inappropriately short or is nan reinit. // THIS SHOULD NEVER ACTUALLY HAPPEN if((fabs(qmag) < 1e-3) || (qmag != qmag)) { q[0] = 1; q[1] = 0; q[2] = 0; q[3] = 0; } AttitudeActualData attitudeActual; AttitudeActualGet(&attitudeActual); quat_copy(q, &attitudeActual.q1); // Convert into eueler degrees (makes assumptions about RPY order) Quaternion2RPY(&attitudeActual.q1,&attitudeActual.Roll); AttitudeActualSet(&attitudeActual); } static void settingsUpdatedCb(UAVObjEvent * objEv) { AttitudeSettingsData attitudeSettings; AttitudeSettingsGet(&attitudeSettings); accelKp = attitudeSettings.AccelKp; accelKi = attitudeSettings.AccelKi; yawBiasRate = attitudeSettings.YawBiasRate; gyroGain = attitudeSettings.GyroGain; zero_during_arming = attitudeSettings.ZeroDuringArming == ATTITUDESETTINGS_ZERODURINGARMING_TRUE; bias_correct_gyro = attitudeSettings.BiasCorrectGyro == ATTITUDESETTINGS_BIASCORRECTGYRO_TRUE; accelbias[0] = attitudeSettings.AccelBias[ATTITUDESETTINGS_ACCELBIAS_X]; accelbias[1] = attitudeSettings.AccelBias[ATTITUDESETTINGS_ACCELBIAS_Y]; accelbias[2] = attitudeSettings.AccelBias[ATTITUDESETTINGS_ACCELBIAS_Z]; gyro_correct_int[0] = attitudeSettings.GyroBias[ATTITUDESETTINGS_GYROBIAS_X] / 100.0f; gyro_correct_int[1] = attitudeSettings.GyroBias[ATTITUDESETTINGS_GYROBIAS_Y] / 100.0f; gyro_correct_int[2] = attitudeSettings.GyroBias[ATTITUDESETTINGS_GYROBIAS_Z] / 100.0f; // Indicates not to expend cycles on rotation if(attitudeSettings.BoardRotation[0] == 0 && attitudeSettings.BoardRotation[1] == 0 && attitudeSettings.BoardRotation[2] == 0) { rotate = 0; // Shouldn't be used but to be safe float rotationQuat[4] = {1,0,0,0}; Quaternion2R(rotationQuat, R); } else { float rotationQuat[4]; const float rpy[3] = {attitudeSettings.BoardRotation[ATTITUDESETTINGS_BOARDROTATION_ROLL], attitudeSettings.BoardRotation[ATTITUDESETTINGS_BOARDROTATION_PITCH], attitudeSettings.BoardRotation[ATTITUDESETTINGS_BOARDROTATION_YAW]}; RPY2Quaternion(rpy, rotationQuat); Quaternion2R(rotationQuat, R); rotate = 1; } if (attitudeSettings.TrimFlight == ATTITUDESETTINGS_TRIMFLIGHT_START) { trim_accels[0] = 0; trim_accels[1] = 0; trim_accels[2] = 0; trim_samples = 0; trim_requested = true; } else if (attitudeSettings.TrimFlight == ATTITUDESETTINGS_TRIMFLIGHT_LOAD) { trim_requested = false; attitudeSettings.AccelBias[ATTITUDESETTINGS_ACCELBIAS_X] = trim_accels[0] / trim_samples; attitudeSettings.AccelBias[ATTITUDESETTINGS_ACCELBIAS_Y] = trim_accels[1] / trim_samples; // Z should average -grav attitudeSettings.AccelBias[ATTITUDESETTINGS_ACCELBIAS_Z] = trim_accels[2] / trim_samples + GRAV / ACCEL_SCALE; attitudeSettings.TrimFlight = ATTITUDESETTINGS_TRIMFLIGHT_NORMAL; AttitudeSettingsSet(&attitudeSettings); } else trim_requested = false; } /** * @} * @} */