void updateBoardAlignment(int16_t roll, int16_t pitch)
{
const float sinAlignYaw = sin_approx(DECIDEGREES_TO_RADIANS(boardAlignment()->yawDeciDegrees));
const float cosAlignYaw = cos_approx(DECIDEGREES_TO_RADIANS(boardAlignment()->yawDeciDegrees));
boardAlignmentMutable()->rollDeciDegrees += -sinAlignYaw * pitch + cosAlignYaw * roll;
boardAlignmentMutable()->pitchDeciDegrees += cosAlignYaw * pitch + sinAlignYaw * roll;
initBoardAlignment();
}
static void imuCalculateEstimatedAttitude(float dT)
{
float courseOverGround = 0;
int accWeight = 0;
bool useMag = false;
bool useCOG = false;
accWeight = imuCalculateAccelerometerConfidence();
if (sensors(SENSOR_MAG) && isMagnetometerHealthy()) {
useMag = true;
}
#if defined(GPS)
else if (STATE(FIXED_WING) && sensors(SENSOR_GPS) && STATE(GPS_FIX) && gpsSol.numSat >= 5 && gpsSol.groundSpeed >= 300) {
// In case of a fixed-wing aircraft we can use GPS course over ground to correct heading
if (gpsHeadingInitialized) {
courseOverGround = DECIDEGREES_TO_RADIANS(gpsSol.groundCourse);
useCOG = true;
}
else {
// Re-initialize quaternion from known Roll, Pitch and GPS heading
imuComputeQuaternionFromRPY(attitude.values.roll, attitude.values.pitch, gpsSol.groundCourse);
gpsHeadingInitialized = true;
}
}
#endif
imuMahonyAHRSupdate(dT, imuMeasuredRotationBF.A[X], imuMeasuredRotationBF.A[Y], imuMeasuredRotationBF.A[Z],
accWeight, imuMeasuredGravityBF.A[X], imuMeasuredGravityBF.A[Y], imuMeasuredGravityBF.A[Z],
useMag, magADC[X], magADC[Y], magADC[Z],
useCOG, courseOverGround);
imuUpdateEulerAngles();
}
void initBoardAlignment(void)
{
if (isBoardAlignmentStandard(boardAlignment())) {
standardBoardAlignment = true;
} else {
fp_angles_t rotationAngles;
standardBoardAlignment = false;
rotationAngles.angles.roll = DECIDEGREES_TO_RADIANS(boardAlignment()->rollDeciDegrees );
rotationAngles.angles.pitch = DECIDEGREES_TO_RADIANS(boardAlignment()->pitchDeciDegrees);
rotationAngles.angles.yaw = DECIDEGREES_TO_RADIANS(boardAlignment()->yawDeciDegrees );
rotationMatrixFromAngles(&boardRotMatrix, &rotationAngles);
}
}
static void imuCalculateEstimatedAttitude(void)
{
static biquad_t accLPFState[3];
static bool accStateIsSet;
static uint32_t previousIMUUpdateTime;
float rawYawError = 0;
int32_t axis;
bool useAcc = false;
bool useMag = false;
bool useYaw = false;
uint32_t currentTime = micros();
uint32_t deltaT = currentTime - previousIMUUpdateTime;
previousIMUUpdateTime = currentTime;
// Smooth and use only valid accelerometer readings
for (axis = 0; axis < 3; axis++) {
if (imuRuntimeConfig->acc_cut_hz) {
if (accStateIsSet) {
accSmooth[axis] = lrintf(applyBiQuadFilter((float) accADC[axis], &accLPFState[axis]));
} else {
for (axis = 0; axis < 3; axis++) BiQuadNewLpf(imuRuntimeConfig->acc_cut_hz, &accLPFState[axis], 1000);
accStateIsSet = true;
}
} else {
accSmooth[axis] = accADC[axis];
}
}
if (imuIsAccelerometerHealthy()) {
useAcc = true;
}
if (sensors(SENSOR_MAG) && isMagnetometerHealthy()) {
useMag = true;
}
#if defined(GPS)
else if (STATE(FIXED_WING) && sensors(SENSOR_GPS) && STATE(GPS_FIX) && GPS_numSat >= 5 && GPS_speed >= 300) {
// In case of a fixed-wing aircraft we can use GPS course over ground to correct heading
rawYawError = DECIDEGREES_TO_RADIANS(attitude.values.yaw - GPS_ground_course);
useYaw = true;
}
#endif
imuMahonyAHRSupdate(deltaT * 1e-6f,
gyroADC[X] * gyroScale, gyroADC[Y] * gyroScale, gyroADC[Z] * gyroScale,
useAcc, accSmooth[X], accSmooth[Y], accSmooth[Z],
useMag, magADC[X], magADC[Y], magADC[Z],
useYaw, rawYawError);
imuUpdateEulerAngles();
imuCalculateAcceleration(deltaT); // rotate acc vector into earth frame
}
void mavlinkSendAttitude(void)
{
uint16_t msgLength;
mavlink_msg_attitude_pack(0, 200, &mavMsg,
// time_boot_ms Timestamp (milliseconds since system boot)
millis(),
// roll Roll angle (rad)
DECIDEGREES_TO_RADIANS(attitude.values.roll),
// pitch Pitch angle (rad)
DECIDEGREES_TO_RADIANS(-attitude.values.pitch),
// yaw Yaw angle (rad)
DECIDEGREES_TO_RADIANS(attitude.values.yaw),
// rollspeed Roll angular speed (rad/s)
0,
// pitchspeed Pitch angular speed (rad/s)
0,
// yawspeed Yaw angular speed (rad/s)
0);
msgLength = mavlink_msg_to_send_buffer(mavBuffer, &mavMsg);
mavlinkSerialWrite(mavBuffer, msgLength);
}
void applyFixedWingPitchRollThrottleController(navigationFSMStateFlags_t navStateFlags, uint32_t currentTime)
{
int16_t pitchCorrection = 0; // >0 climb, <0 dive
int16_t rollCorrection = 0; // >0 right, <0 left
int16_t throttleCorrection = 0; // raw throttle
int16_t minThrottleCorrection = posControl.navConfig->fw_min_throttle - posControl.navConfig->fw_cruise_throttle;
int16_t maxThrottleCorrection = posControl.navConfig->fw_max_throttle - posControl.navConfig->fw_cruise_throttle;
// Mix Pitch/Roll/Throttle
if (isPitchAdjustmentValid && (navStateFlags & NAV_CTL_ALT)) {
pitchCorrection += posControl.rcAdjustment[PITCH];
throttleCorrection += DECIDEGREES_TO_DEGREES(posControl.rcAdjustment[PITCH]) * posControl.navConfig->fw_pitch_to_throttle;
throttleCorrection = constrain(throttleCorrection, minThrottleCorrection, maxThrottleCorrection);
}
if (isRollAdjustmentValid && (navStateFlags & NAV_CTL_POS)) {
pitchCorrection += ABS(posControl.rcAdjustment[ROLL]) * (posControl.navConfig->fw_roll_to_pitch / 100.0f);
rollCorrection += posControl.rcAdjustment[ROLL];
}
// Speed controller - only apply in POS mode
if (navStateFlags & NAV_CTL_POS) {
throttleCorrection += applyFixedWingMinSpeedController(currentTime);
throttleCorrection = constrain(throttleCorrection, minThrottleCorrection, maxThrottleCorrection);
}
// Limit and apply
if (isPitchAdjustmentValid && (navStateFlags & NAV_CTL_ALT)) {
// PITCH angle is measured in opposite direction ( >0 - dive, <0 - climb)
pitchCorrection = constrain(pitchCorrection, -DEGREES_TO_CENTIDEGREES(posControl.navConfig->fw_max_dive_angle), DEGREES_TO_CENTIDEGREES(posControl.navConfig->fw_max_climb_angle));
rcCommand[PITCH] = -pidAngleToRcCommand(pitchCorrection, posControl.pidProfile->max_angle_inclination[FD_PITCH]);
}
if (isRollAdjustmentValid && (navStateFlags & NAV_CTL_POS)) {
rollCorrection = constrain(rollCorrection, -DEGREES_TO_CENTIDEGREES(posControl.navConfig->fw_max_bank_angle), DEGREES_TO_CENTIDEGREES(posControl.navConfig->fw_max_bank_angle));
rcCommand[ROLL] = pidAngleToRcCommand(rollCorrection, posControl.pidProfile->max_angle_inclination[FD_ROLL]);
// Calculate coordinated turn rate based on velocity and banking angle
if (posControl.actualState.velXY >= 300.0f) {
float targetYawRateDPS = RADIANS_TO_DEGREES(tan_approx(DECIDEGREES_TO_RADIANS(-rollCorrection)) * GRAVITY_CMSS / posControl.actualState.velXY);
rcCommand[YAW] = pidRateToRcCommand(targetYawRateDPS, currentControlRateProfile->rates[FD_YAW]);
}
else {
rcCommand[YAW] = 0;
}
}
if ((navStateFlags & NAV_CTL_ALT) || (navStateFlags & NAV_CTL_POS)) {
uint16_t correctedThrottleValue = constrain(posControl.navConfig->fw_cruise_throttle + throttleCorrection, posControl.navConfig->fw_min_throttle, posControl.navConfig->fw_max_throttle);
rcCommand[THROTTLE] = constrain(correctedThrottleValue, posControl.escAndServoConfig->minthrottle, posControl.escAndServoConfig->maxthrottle);
}
}
STATIC_UNIT_TESTED void imuComputeQuaternionFromRPY(int16_t initialRoll, int16_t initialPitch, int16_t initialYaw)
{
if (initialRoll > 1800) initialRoll -= 3600;
if (initialPitch > 1800) initialPitch -= 3600;
if (initialYaw > 1800) initialYaw -= 3600;
float cosRoll = cos_approx(DECIDEGREES_TO_RADIANS(initialRoll) * 0.5f);
float sinRoll = sin_approx(DECIDEGREES_TO_RADIANS(initialRoll) * 0.5f);
float cosPitch = cos_approx(DECIDEGREES_TO_RADIANS(initialPitch) * 0.5f);
float sinPitch = sin_approx(DECIDEGREES_TO_RADIANS(initialPitch) * 0.5f);
float cosYaw = cos_approx(DECIDEGREES_TO_RADIANS(-initialYaw) * 0.5f);
float sinYaw = sin_approx(DECIDEGREES_TO_RADIANS(-initialYaw) * 0.5f);
q0 = cosRoll * cosPitch * cosYaw + sinRoll * sinPitch * sinYaw;
q1 = sinRoll * cosPitch * cosYaw - cosRoll * sinPitch * sinYaw;
q2 = cosRoll * sinPitch * cosYaw + sinRoll * cosPitch * sinYaw;
q3 = cosRoll * cosPitch * sinYaw - sinRoll * sinPitch * cosYaw;
imuComputeRotationMatrix();
}