void stabilization_attitude_ref_update(void) { /* integrate reference attitude */ #if STABILIZATION_ATTITUDE_REF_QUAT_INFINITESIMAL_STEP struct FloatQuat qdot; FLOAT_QUAT_DERIVATIVE(qdot, stab_att_ref_rate, stab_att_ref_quat); QUAT_SMUL(qdot, qdot, DT_UPDATE); QUAT_ADD(stab_att_ref_quat, qdot); #else // use finite step (involves trig) struct FloatQuat delta_q; FLOAT_QUAT_DIFFERENTIAL(delta_q, stab_att_ref_rate, DT_UPDATE); /* compose new ref_quat by quaternion multiplication of delta rotation and current ref_quat */ struct FloatQuat new_ref_quat; FLOAT_QUAT_COMP(new_ref_quat, delta_q, stab_att_ref_quat); QUAT_COPY(stab_att_ref_quat, new_ref_quat); #endif FLOAT_QUAT_NORMALIZE(stab_att_ref_quat); /* integrate reference rotational speeds */ struct FloatRates delta_rate; RATES_SMUL(delta_rate, stab_att_ref_accel, DT_UPDATE); RATES_ADD(stab_att_ref_rate, delta_rate); /* compute reference angular accelerations */ struct FloatQuat err; /* compute reference attitude error */ FLOAT_QUAT_INV_COMP(err, stab_att_sp_quat, stab_att_ref_quat); /* wrap it in the shortest direction */ FLOAT_QUAT_WRAP_SHORTEST(err); /* propagate the 2nd order linear model */ stab_att_ref_accel.p = -2.*stab_att_ref_model[ref_idx].zeta.p*stab_att_ref_model[ref_idx].omega.p*stab_att_ref_rate.p - stab_att_ref_model[ref_idx].omega.p*stab_att_ref_model[ref_idx].omega.p*err.qx; stab_att_ref_accel.q = -2.*stab_att_ref_model[ref_idx].zeta.q*stab_att_ref_model[ref_idx].omega.q*stab_att_ref_rate.q - stab_att_ref_model[ref_idx].omega.q*stab_att_ref_model[ref_idx].omega.q*err.qy; stab_att_ref_accel.r = -2.*stab_att_ref_model[ref_idx].zeta.r*stab_att_ref_model[ref_idx].omega.r*stab_att_ref_rate.r - stab_att_ref_model[ref_idx].omega.r*stab_att_ref_model[ref_idx].omega.r*err.qz; /* saturate acceleration */ const struct FloatRates MIN_ACCEL = { -REF_ACCEL_MAX_P, -REF_ACCEL_MAX_Q, -REF_ACCEL_MAX_R }; const struct FloatRates MAX_ACCEL = { REF_ACCEL_MAX_P, REF_ACCEL_MAX_Q, REF_ACCEL_MAX_R }; RATES_BOUND_BOX(stab_att_ref_accel, MIN_ACCEL, MAX_ACCEL); /* saturate angular speed and trim accel accordingly */ SATURATE_SPEED_TRIM_ACCEL(); /* compute ref_euler */ FLOAT_EULERS_OF_QUAT(stab_att_ref_euler, stab_att_ref_quat); }
void stabilization_attitude_ref_update() { #if USE_REF /* dumb integrate reference attitude */ struct FloatRates delta_rate; RATES_SMUL(delta_rate, stab_att_ref_rate, DT_UPDATE); struct FloatEulers delta_angle; EULERS_ASSIGN(delta_angle, delta_rate.p, delta_rate.q, delta_rate.r); EULERS_ADD(stab_att_ref_euler, delta_angle); FLOAT_ANGLE_NORMALIZE(stab_att_ref_euler.psi); /* integrate reference rotational speeds */ struct FloatRates delta_accel; RATES_SMUL(delta_accel, stab_att_ref_accel, DT_UPDATE); RATES_ADD(stab_att_ref_rate, delta_accel); /* compute reference attitude error */ struct FloatEulers ref_err; EULERS_DIFF(ref_err, stab_att_ref_euler, stab_att_sp_euler); /* wrap it in the shortest direction */ FLOAT_ANGLE_NORMALIZE(ref_err.psi); /* compute reference angular accelerations */ stab_att_ref_accel.p = -2.*ZETA_P * OMEGA_P * stab_att_ref_rate.p - OMEGA_P * OMEGA_P * ref_err.phi; stab_att_ref_accel.q = -2.*ZETA_Q * OMEGA_P * stab_att_ref_rate.q - OMEGA_Q * OMEGA_Q * ref_err.theta; stab_att_ref_accel.r = -2.*ZETA_R * OMEGA_P * stab_att_ref_rate.r - OMEGA_R * OMEGA_R * ref_err.psi; /* saturate acceleration */ const struct FloatRates MIN_ACCEL = { -REF_ACCEL_MAX_P, -REF_ACCEL_MAX_Q, -REF_ACCEL_MAX_R }; const struct FloatRates MAX_ACCEL = { REF_ACCEL_MAX_P, REF_ACCEL_MAX_Q, REF_ACCEL_MAX_R }; RATES_BOUND_BOX(stab_att_ref_accel, MIN_ACCEL, MAX_ACCEL); /* saturate speed and trim accel accordingly */ SATURATE_SPEED_TRIM_ACCEL(); #else /* !USE_REF */ EULERS_COPY(stab_att_ref_euler, stabilization_att_sp); FLOAT_RATES_ZERO(stab_att_ref_rate); FLOAT_RATES_ZERO(stab_att_ref_accel); #endif /* USE_REF */ }