void ahrs_float_invariant_propagate(struct FloatRates* gyro, float dt)
{
// realign all the filter if needed
// a complete init cycle is required
if (ahrs_float_inv.reset) {
ahrs_float_inv.reset = false;
ahrs_float_inv.is_aligned = false;
init_invariant_state();
}
// fill command vector
struct FloatRates gyro_meas_body;
struct FloatRMat *body_to_imu_rmat = orientationGetRMat_f(&ahrs_float_inv.body_to_imu);
float_rmat_transp_ratemult(&gyro_meas_body, body_to_imu_rmat, gyro);
ahrs_float_inv.cmd.rates = gyro_meas_body;
// update correction gains
error_output(&ahrs_float_inv);
// propagate model
struct inv_state new_state;
runge_kutta_4_float((float *)&new_state,
(float *)&ahrs_float_inv.state, INV_STATE_DIM,
(float *)&ahrs_float_inv.cmd, INV_COMMAND_DIM,
invariant_model, dt);
ahrs_float_inv.state = new_state;
// normalize quaternion
float_quat_normalize(&ahrs_float_inv.state.quat);
//------------------------------------------------------------//
#if SEND_INVARIANT_FILTER
struct FloatEulers eulers;
float foo = 0.f;
float_eulers_of_quat(&eulers, &ahrs_float_inv.state.quat);
RunOnceEvery(3,
pprz_msg_send_INV_FILTER(&(DefaultChannel).trans_tx, &(DefaultDevice).device,
AC_ID,
&ahrs_float_inv.state.quat.qi,
&eulers.phi,
&eulers.theta,
&eulers.psi,
&foo,
&foo,
&foo,
&foo,
&foo,
&foo,
&ahrs_float_inv.state.bias.p,
&ahrs_float_inv.state.bias.q,
&ahrs_float_inv.state.bias.r,
&ahrs_float_inv.state.as,
&ahrs_float_inv.state.cs,
&foo,
&foo);
);
void ahrs_fc_set_body_to_imu_quat(struct FloatQuat *q_b2i)
{
orientationSetQuat_f(&ahrs_fc.body_to_imu, q_b2i);
if (!ahrs_fc.is_aligned) {
/* Set ltp_to_imu so that body is zero */
ahrs_fc.ltp_to_imu_quat = *orientationGetQuat_f(&ahrs_fc.body_to_imu);
ahrs_fc.ltp_to_imu_rmat = *orientationGetRMat_f(&ahrs_fc.body_to_imu);
}
}
/**
* Read received data
*/
void ahrs_vectornav_propagate(void)
{
// Rates [rad/s]
static struct FloatRates body_rate;
float_rmat_ratemult(&body_rate, orientationGetRMat_f(&ahrs_vn.body_to_imu), &ahrs_vn.vn_data.gyro); // compute body rates
stateSetBodyRates_f(&body_rate); // Set state [rad/s]
// Attitude [deg]
static struct FloatQuat imu_quat; // convert from euler to quat
float_quat_of_eulers(&imu_quat, &ahrs_vn.vn_data.attitude);
stateSetNedToBodyQuat_f(&imu_quat);
}
/**
* Compute body orientation and rates from imu orientation and rates
*/
static inline void compute_body_orientation_and_rates(void) {
/* Compute LTP to BODY quaternion */
struct FloatQuat ltp_to_body_quat;
struct FloatQuat *body_to_imu_quat = orientationGetQuat_f(&imu.body_to_imu);
float_quat_comp_inv(<p_to_body_quat, &ahrs_impl.ltp_to_imu_quat, body_to_imu_quat);
/* Set state */
stateSetNedToBodyQuat_f(<p_to_body_quat);
/* compute body rates */
struct FloatRates body_rate;
struct FloatRMat *body_to_imu_rmat = orientationGetRMat_f(&imu.body_to_imu);
float_rmat_transp_ratemult(&body_rate, body_to_imu_rmat, &ahrs_impl.imu_rate);
stateSetBodyRates_f(&body_rate);
}
void ahrs_init(void) {
ahrs.status = AHRS_UNINIT;
/* Set ltp_to_imu so that body is zero */
memcpy(&ahrs_impl.ltp_to_imu_euler, orientationGetEulers_f(&imu.body_to_imu),
sizeof(struct FloatEulers));
FLOAT_RATES_ZERO(ahrs_impl.imu_rate);
/* set inital filter dcm */
set_dcm_matrix_from_rmat(orientationGetRMat_f(&imu.body_to_imu));
ahrs_impl.gps_speed = 0;
ahrs_impl.gps_acceleration = 0;
ahrs_impl.gps_course = 0;
ahrs_impl.gps_course_valid = FALSE;
ahrs_impl.gps_age = 100;
}
void ahrs_dcm_init(void)
{
ahrs_dcm.status = AHRS_DCM_UNINIT;
ahrs_dcm.is_aligned = FALSE;
/* init ltp_to_imu euler with zero */
FLOAT_EULERS_ZERO(ahrs_dcm.ltp_to_imu_euler);
FLOAT_RATES_ZERO(ahrs_dcm.imu_rate);
/* set inital filter dcm */
set_dcm_matrix_from_rmat(orientationGetRMat_f(&ahrs_dcm.body_to_imu));
ahrs_dcm.gps_speed = 0;
ahrs_dcm.gps_acceleration = 0;
ahrs_dcm.gps_course = 0;
ahrs_dcm.gps_course_valid = FALSE;
ahrs_dcm.gps_age = 100;
}
/*
* Compute body orientation and rates from imu orientation and rates
*/
static inline void set_body_orientation_and_rates(void) {
struct FloatRMat *body_to_imu_rmat = orientationGetRMat_f(&imu.body_to_imu);
struct FloatRates body_rate;
FLOAT_RMAT_TRANSP_RATEMULT(body_rate, *body_to_imu_rmat, ahrs_impl.imu_rate);
stateSetBodyRates_f(&body_rate);
struct FloatRMat ltp_to_imu_rmat, ltp_to_body_rmat;
FLOAT_RMAT_OF_EULERS(ltp_to_imu_rmat, ahrs_impl.ltp_to_imu_euler);
FLOAT_RMAT_COMP_INV(ltp_to_body_rmat, ltp_to_imu_rmat, *body_to_imu_rmat);
// Some stupid lines of code for neutrals
struct FloatEulers ltp_to_body_euler;
FLOAT_EULERS_OF_RMAT(ltp_to_body_euler, ltp_to_body_rmat);
ltp_to_body_euler.phi -= ins_roll_neutral;
ltp_to_body_euler.theta -= ins_pitch_neutral;
stateSetNedToBodyEulers_f(<p_to_body_euler);
// should be replaced at the end by:
// stateSetNedToBodyRMat_f(<p_to_body_rmat);
}
void ahrs_init(void) {
ahrs.status = AHRS_UNINIT;
ahrs_impl.ltp_vel_norm_valid = FALSE;
ahrs_impl.heading_aligned = FALSE;
/* Set ltp_to_imu so that body is zero */
memcpy(&ahrs_impl.ltp_to_imu_quat, orientationGetQuat_f(&imu.body_to_imu),
sizeof(struct FloatQuat));
memcpy(&ahrs_impl.ltp_to_imu_rmat, orientationGetRMat_f(&imu.body_to_imu),
sizeof(struct FloatRMat));
FLOAT_RATES_ZERO(ahrs_impl.imu_rate);
/* set default filter cut-off frequency and damping */
ahrs_impl.accel_omega = AHRS_ACCEL_OMEGA;
ahrs_impl.accel_zeta = AHRS_ACCEL_ZETA;
ahrs_impl.mag_omega = AHRS_MAG_OMEGA;
ahrs_impl.mag_zeta = AHRS_MAG_ZETA;
#if AHRS_GRAVITY_UPDATE_COORDINATED_TURN
ahrs_impl.correct_gravity = TRUE;
#else
ahrs_impl.correct_gravity = FALSE;
#endif
ahrs_impl.gravity_heuristic_factor = AHRS_GRAVITY_HEURISTIC_FACTOR;
VECT3_ASSIGN(ahrs_impl.mag_h, AHRS_H_X, AHRS_H_Y, AHRS_H_Z);
ahrs_impl.accel_cnt = 0;
ahrs_impl.mag_cnt = 0;
#if PERIODIC_TELEMETRY
register_periodic_telemetry(DefaultPeriodic, "AHRS_EULER_INT", send_att);
register_periodic_telemetry(DefaultPeriodic, "GEO_MAG", send_geo_mag);
#endif
}
/**
* Propagate the received states into the vehicle
* state machine
*/
void ins_vectornav_propagate()
{
// Acceleration [m/s^2]
// in fixed point for sending as ABI and telemetry msgs
ACCELS_BFP_OF_REAL(ins_vn.accel_i, ins_vn.accel);
// Rates [rad/s]
static struct FloatRates body_rate;
// in fixed point for sending as ABI and telemetry msgs
RATES_BFP_OF_REAL(ins_vn.gyro_i, ins_vn.gyro);
float_rmat_ratemult(&body_rate, orientationGetRMat_f(&ins_vn.body_to_imu), &ins_vn.gyro); // compute body rates
stateSetBodyRates_f(&body_rate); // Set state [rad/s]
// Attitude [deg]
ins_vectornav_yaw_pitch_roll_to_attitude(&ins_vn.attitude); // convert to correct units and axis [rad]
static struct FloatQuat imu_quat; // convert from euler to quat
float_quat_of_eulers(&imu_quat, &ins_vn.attitude);
static struct FloatRMat imu_rmat; // convert from quat to rmat
float_rmat_of_quat(&imu_rmat, &imu_quat);
static struct FloatRMat ltp_to_body_rmat; // rotate to body frame
float_rmat_comp(<p_to_body_rmat, &imu_rmat, orientationGetRMat_f(&ins_vn.body_to_imu));
stateSetNedToBodyRMat_f(<p_to_body_rmat); // set body states [rad]
// NED (LTP) velocity [m/s]
// North east down (NED), also known as local tangent plane (LTP),
// is a geographical coordinate system for representing state vectors that is commonly used in aviation.
// It consists of three numbers: one represents the position along the northern axis,
// one along the eastern axis, and one represents vertical position. Down is chosen as opposed to
// up in order to comply with the right-hand rule.
// The origin of this coordinate system is usually chosen to be the aircraft's center of gravity.
// x = North
// y = East
// z = Down
stateSetSpeedNed_f(&ins_vn.vel_ned); // set state
// NED (LTP) acceleration [m/s^2]
static struct FloatVect3 accel_meas_ltp;// first we need to rotate linear acceleration from imu-frame to body-frame
float_rmat_transp_vmult(&accel_meas_ltp, orientationGetRMat_f(&ins_vn.body_to_imu), &(ins_vn.lin_accel));
static struct NedCoor_f ltp_accel; // assign to NedCoord_f struct
VECT3_ASSIGN(ltp_accel, accel_meas_ltp.x, accel_meas_ltp.y, accel_meas_ltp.z);
stateSetAccelNed_f(<p_accel); // then set the states
ins_vn.ltp_accel_f = ltp_accel;
// LLA position [rad, rad, m]
//static struct LlaCoor_f lla_pos; // convert from deg to rad, and from double to float
ins_vn.lla_pos.lat = RadOfDeg((float)ins_vn.pos_lla[0]); // ins_impl.pos_lla[0] = lat
ins_vn.lla_pos.lon = RadOfDeg((float)ins_vn.pos_lla[1]); // ins_impl.pos_lla[1] = lon
ins_vn.lla_pos.alt = ((float)ins_vn.pos_lla[2]); // ins_impl.pos_lla[2] = alt
LLA_BFP_OF_REAL(gps.lla_pos, ins_vn.lla_pos);
stateSetPositionLla_i(&gps.lla_pos);
// ECEF position
struct LtpDef_f def;
ltp_def_from_lla_f(&def, &ins_vn.lla_pos);
struct EcefCoor_f ecef_vel;
ecef_of_ned_point_f(&ecef_vel, &def, &ins_vn.vel_ned);
ECEF_BFP_OF_REAL(gps.ecef_vel, ecef_vel);
// ECEF velocity
gps.ecef_pos.x = stateGetPositionEcef_i()->x;
gps.ecef_pos.y = stateGetPositionEcef_i()->y;
gps.ecef_pos.z = stateGetPositionEcef_i()->z;
#if GPS_USE_LATLONG
// GPS UTM
/* Computes from (lat, long) in the referenced UTM zone */
struct UtmCoor_f utm_f;
utm_f.zone = nav_utm_zone0;
/* convert to utm */
//utm_of_lla_f(&utm_f, &lla_f);
utm_of_lla_f(&utm_f, &ins_vn.lla_pos);
/* copy results of utm conversion */
gps.utm_pos.east = (int32_t)(utm_f.east * 100);
gps.utm_pos.north = (int32_t)(utm_f.north * 100);
gps.utm_pos.alt = (int32_t)(utm_f.alt * 1000);
gps.utm_pos.zone = (uint8_t)nav_utm_zone0;
#endif
// GPS Ground speed
float speed = sqrt(ins_vn.vel_ned.x * ins_vn.vel_ned.x + ins_vn.vel_ned.y * ins_vn.vel_ned.y);
gps.gspeed = ((uint16_t)(speed * 100));
// GPS course
gps.course = (int32_t)(1e7 * (atan2(ins_vn.vel_ned.y, ins_vn.vel_ned.x)));
// Because we have not HMSL data from Vectornav, we are using LLA-Altitude
// as a workaround
gps.hmsl = (uint32_t)(gps.lla_pos.alt);
// set position uncertainty
ins_vectornav_set_pacc();
// set velocity uncertainty
ins_vectornav_set_sacc();
// check GPS status
gps.last_msg_time = sys_time.nb_sec;
gps.last_msg_ticks = sys_time.nb_sec_rem;
if (gps.fix == GPS_FIX_3D) {
gps.last_3dfix_time = sys_time.nb_sec;
gps.last_3dfix_ticks = sys_time.nb_sec_rem;
}
// read INS status
ins_vectornav_check_status();
// update internal states for telemetry purposes
// TODO: directly convert vectornav output instead of using state interface
// to support multiple INS running at the same time
ins_vn.ltp_pos_i = *stateGetPositionNed_i();
ins_vn.ltp_speed_i = *stateGetSpeedNed_i();
ins_vn.ltp_accel_i = *stateGetAccelNed_i();
// send ABI messages
uint32_t now_ts = get_sys_time_usec();
AbiSendMsgGPS(GPS_UBX_ID, now_ts, &gps);
AbiSendMsgIMU_GYRO_INT32(IMU_ASPIRIN_ID, now_ts, &ins_vn.gyro_i);
AbiSendMsgIMU_ACCEL_INT32(IMU_ASPIRIN_ID, now_ts, &ins_vn.accel_i);
}
void ahrs_fc_update_accel(struct Int32Vect3 *accel, float dt)
{
// check if we had at least one propagation since last update
if (ahrs_fc.accel_cnt == 0) {
return;
}
/* last column of roation matrix = ltp z-axis in imu-frame */
struct FloatVect3 c2 = { RMAT_ELMT(ahrs_fc.ltp_to_imu_rmat, 0, 2),
RMAT_ELMT(ahrs_fc.ltp_to_imu_rmat, 1, 2),
RMAT_ELMT(ahrs_fc.ltp_to_imu_rmat, 2, 2)
};
struct FloatVect3 imu_accel_float;
ACCELS_FLOAT_OF_BFP(imu_accel_float, *accel);
struct FloatVect3 residual;
struct FloatVect3 pseudo_gravity_measurement;
if (ahrs_fc.correct_gravity && ahrs_fc.ltp_vel_norm_valid) {
/*
* centrifugal acceleration in body frame
* a_c_body = omega x (omega x r)
* (omega x r) = tangential velocity in body frame
* a_c_body = omega x vel_tangential_body
* assumption: tangential velocity only along body x-axis
*/
const struct FloatVect3 vel_tangential_body = {ahrs_fc.ltp_vel_norm, 0.0, 0.0};
struct FloatRMat *body_to_imu_rmat = orientationGetRMat_f(&ahrs_fc.body_to_imu);
struct FloatRates body_rate;
float_rmat_transp_ratemult(&body_rate, body_to_imu_rmat, &ahrs_fc.imu_rate);
struct FloatVect3 acc_c_body;
VECT3_RATES_CROSS_VECT3(acc_c_body, body_rate, vel_tangential_body);
/* convert centrifugal acceleration from body to imu frame */
struct FloatVect3 acc_c_imu;
float_rmat_vmult(&acc_c_imu, body_to_imu_rmat, &acc_c_body);
/* and subtract it from imu measurement to get a corrected measurement of the gravity vector */
VECT3_DIFF(pseudo_gravity_measurement, imu_accel_float, acc_c_imu);
} else {
VECT3_COPY(pseudo_gravity_measurement, imu_accel_float);
}
VECT3_CROSS_PRODUCT(residual, pseudo_gravity_measurement, c2);
/* FIR filtered pseudo_gravity_measurement */
#define FIR_FILTER_SIZE 8
static struct FloatVect3 filtered_gravity_measurement = {0., 0., 0.};
VECT3_SMUL(filtered_gravity_measurement, filtered_gravity_measurement, FIR_FILTER_SIZE - 1);
VECT3_ADD(filtered_gravity_measurement, pseudo_gravity_measurement);
VECT3_SDIV(filtered_gravity_measurement, filtered_gravity_measurement, FIR_FILTER_SIZE);
if (ahrs_fc.gravity_heuristic_factor) {
/* heuristic on acceleration (gravity estimate) norm */
/* Factor how strongly to change the weight.
* e.g. for gravity_heuristic_factor 30:
* <0.66G = 0, 1G = 1.0, >1.33G = 0
*/
const float g_meas_norm = float_vect3_norm(&filtered_gravity_measurement) / 9.81;
ahrs_fc.weight = 1.0 - ahrs_fc.gravity_heuristic_factor * fabs(1.0 - g_meas_norm) / 10.0;
Bound(ahrs_fc.weight, 0.15, 1.0);
} else {
ahrs_fc.weight = 1.0;
}
/* Complementary filter proportional gain.
* Kp = 2 * zeta * omega * weight * ahrs_fc.accel_cnt
* with ahrs_fc.accel_cnt beeing the number of propagations since last update
*/
const float gravity_rate_update_gain = -2 * ahrs_fc.accel_zeta * ahrs_fc.accel_omega *
ahrs_fc.weight * ahrs_fc.accel_cnt / 9.81;
RATES_ADD_SCALED_VECT(ahrs_fc.rate_correction, residual, gravity_rate_update_gain);
// reset accel propagation counter
ahrs_fc.accel_cnt = 0;
/* Complementary filter integral gain
* Correct the gyro bias.
* Ki = (omega*weight)^2 * dt
*/
const float gravity_bias_update_gain = ahrs_fc.accel_omega * ahrs_fc.accel_omega *
ahrs_fc.weight * ahrs_fc.weight * dt / 9.81;
RATES_ADD_SCALED_VECT(ahrs_fc.gyro_bias, residual, gravity_bias_update_gain);
/* FIXME: saturate bias */
}
void Normalize(void)
{
float error = 0;
float temporary[3][3];
float renorm = 0;
uint8_t problem = FALSE;
// Find the non-orthogonality of X wrt Y
error = -Vector_Dot_Product(&DCM_Matrix[0][0], &DCM_Matrix[1][0]) * .5; //eq.19
// Add half the XY error to X, and half to Y
Vector_Scale(&temporary[0][0], &DCM_Matrix[1][0], error); //eq.19
Vector_Scale(&temporary[1][0], &DCM_Matrix[0][0], error); //eq.19
Vector_Add(&temporary[0][0], &temporary[0][0], &DCM_Matrix[0][0]); //eq.19
Vector_Add(&temporary[1][0], &temporary[1][0], &DCM_Matrix[1][0]); //eq.19
// The third axis is simply set perpendicular to the first 2. (there is not correction of XY based on Z)
Vector_Cross_Product(&temporary[2][0], &temporary[0][0], &temporary[1][0]); // c= a x b //eq.20
// Normalize lenght of X
renorm = Vector_Dot_Product(&temporary[0][0], &temporary[0][0]);
// a) if norm is close to 1, use the fast 1st element from the tailer expansion of SQRT
// b) if the norm is further from 1, use a real sqrt
// c) norm is huge: disaster! reset! mayday!
if (renorm < 1.5625f && renorm > 0.64f) {
renorm = .5 * (3 - renorm); //eq.21
} else if (renorm < 100.0f && renorm > 0.01f) {
renorm = 1. / sqrt(renorm);
#if PERFORMANCE_REPORTING == 1
renorm_sqrt_count++;
#endif
} else {
problem = TRUE;
#if PERFORMANCE_REPORTING == 1
renorm_blowup_count++;
#endif
}
Vector_Scale(&DCM_Matrix[0][0], &temporary[0][0], renorm);
// Normalize lenght of Y
renorm = Vector_Dot_Product(&temporary[1][0], &temporary[1][0]);
if (renorm < 1.5625f && renorm > 0.64f) {
renorm = .5 * (3 - renorm); //eq.21
} else if (renorm < 100.0f && renorm > 0.01f) {
renorm = 1. / sqrt(renorm);
#if PERFORMANCE_REPORTING == 1
renorm_sqrt_count++;
#endif
} else {
problem = TRUE;
#if PERFORMANCE_REPORTING == 1
renorm_blowup_count++;
#endif
}
Vector_Scale(&DCM_Matrix[1][0], &temporary[1][0], renorm);
// Normalize lenght of Z
renorm = Vector_Dot_Product(&temporary[2][0], &temporary[2][0]);
if (renorm < 1.5625f && renorm > 0.64f) {
renorm = .5 * (3 - renorm); //eq.21
} else if (renorm < 100.0f && renorm > 0.01f) {
renorm = 1. / sqrt(renorm);
#if PERFORMANCE_REPORTING == 1
renorm_sqrt_count++;
#endif
} else {
problem = TRUE;
#if PERFORMANCE_REPORTING == 1
renorm_blowup_count++;
#endif
}
Vector_Scale(&DCM_Matrix[2][0], &temporary[2][0], renorm);
// Reset on trouble
if (problem) { // Our solution is blowing up and we will force back to initial condition. Hope we are not upside down!
set_dcm_matrix_from_rmat(orientationGetRMat_f(&ahrs_dcm.body_to_imu));
problem = FALSE;
}
}
void gx3_packet_read_message(void) {
ahrs_impl.gx3_accel.x = bef(&ahrs_impl.gx3_packet.msg_buf[1]);
ahrs_impl.gx3_accel.y = bef(&ahrs_impl.gx3_packet.msg_buf[5]);
ahrs_impl.gx3_accel.z = bef(&ahrs_impl.gx3_packet.msg_buf[9]);
ahrs_impl.gx3_rate.p = bef(&ahrs_impl.gx3_packet.msg_buf[13]);
ahrs_impl.gx3_rate.q = bef(&ahrs_impl.gx3_packet.msg_buf[17]);
ahrs_impl.gx3_rate.r = bef(&ahrs_impl.gx3_packet.msg_buf[21]);
ahrs_impl.gx3_rmat.m[0] = bef(&ahrs_impl.gx3_packet.msg_buf[25]);
ahrs_impl.gx3_rmat.m[1] = bef(&ahrs_impl.gx3_packet.msg_buf[29]);
ahrs_impl.gx3_rmat.m[2] = bef(&ahrs_impl.gx3_packet.msg_buf[33]);
ahrs_impl.gx3_rmat.m[3] = bef(&ahrs_impl.gx3_packet.msg_buf[37]);
ahrs_impl.gx3_rmat.m[4] = bef(&ahrs_impl.gx3_packet.msg_buf[41]);
ahrs_impl.gx3_rmat.m[5] = bef(&ahrs_impl.gx3_packet.msg_buf[45]);
ahrs_impl.gx3_rmat.m[6] = bef(&ahrs_impl.gx3_packet.msg_buf[49]);
ahrs_impl.gx3_rmat.m[7] = bef(&ahrs_impl.gx3_packet.msg_buf[53]);
ahrs_impl.gx3_rmat.m[8] = bef(&ahrs_impl.gx3_packet.msg_buf[57]);
ahrs_impl.gx3_time = (uint32_t)(ahrs_impl.gx3_packet.msg_buf[61] << 24 |
ahrs_impl.gx3_packet.msg_buf[62] << 16 | ahrs_impl.gx3_packet.msg_buf[63] << 8 | ahrs_impl.gx3_packet.msg_buf[64]);
ahrs_impl.gx3_chksm = GX3_CHKSM(ahrs_impl.gx3_packet.msg_buf);
ahrs_impl.gx3_freq = 62500.0 / (float)(ahrs_impl.gx3_time - ahrs_impl.gx3_ltime);
ahrs_impl.gx3_ltime = ahrs_impl.gx3_time;
// Acceleration
VECT3_SMUL(ahrs_impl.gx3_accel, ahrs_impl.gx3_accel, 9.80665); // Convert g into m/s2
ACCELS_BFP_OF_REAL(imu.accel, ahrs_impl.gx3_accel); // for backwards compatibility with fixed point interface
imuf.accel = ahrs_impl.gx3_accel;
// Rates
struct FloatRates body_rate;
imuf.gyro = ahrs_impl.gx3_rate;
/* compute body rates */
struct FloatRMat *body_to_imu_rmat = orientationGetRMat_f(&imuf.body_to_imu);
FLOAT_RMAT_TRANSP_RATEMULT(body_rate, *body_to_imu_rmat, imuf.gyro);
/* Set state */
stateSetBodyRates_f(&body_rate);
// Attitude
struct FloatRMat ltp_to_body_rmat;
FLOAT_RMAT_COMP(ltp_to_body_rmat, ahrs_impl.gx3_rmat, *body_to_imu_rmat);
#if AHRS_USE_GPS_HEADING && USE_GPS
struct FloatEulers ltp_to_body_eulers;
float_eulers_of_rmat(<p_to_body_eulers, <p_to_body_rmat);
float course_f = (float)DegOfRad(gps.course / 1e7);
if (course_f > 180.0) {
course_f -= 360.0;
}
ltp_to_body_eulers.psi = (float)RadOfDeg(course_f);
stateSetNedToBodyEulers_f(<p_to_body_eulers);
#else // !AHRS_USE_GPS_HEADING
#ifdef IMU_MAG_OFFSET
struct FloatEulers ltp_to_body_eulers;
float_eulers_of_rmat(<p_to_body_eulers, <p_to_body_rmat);
ltp_to_body_eulers.psi -= ahrs_impl.mag_offset;
stateSetNedToBodyEulers_f(<p_to_body_eulers);
#else
stateSetNedToBodyRMat_f(<p_to_body_rmat);
#endif // IMU_MAG_OFFSET
#endif // !AHRS_USE_GPS_HEADING
}
