Function navtk::inertial::mechanization_wander(const Vector3&, const Vector3&, double, const Matrix3&, double, const Vector3&, const Matrix3&, const MechanizationOptions&, AidingAltData *)

Function Documentation

std::tuple<Matrix3, double, Vector3, Matrix3> navtk::inertial::mechanization_wander(const Vector3 &dv_s, const Vector3 &dth_s, double dt, const Matrix3 &C_n_to_e_0, double h0, const Vector3 &v_n_0, const Matrix3 &C_s_to_l_0, const MechanizationOptions &mech_options = MechanizationOptions{}, AidingAltData *aiding_alt_data = nullptr)

Performs a single mechanization in the wander azimuth frame.

Based on equations found in Strapdown Analytics by Paul Savage, primarily Vol 1, Ch. 7.

Parameters

  • dv_s – Vector3 of delta velocity measurements in the inertial sensor frame, m/s.

  • dth_s – Vector3 of delta rotation measurements in the inertial sensor frame, rad.

  • dt – Delta time over which dv_s and dth_s are valid, seconds.

  • C_n_to_e_0 – DCM that rotates from Savage defined ‘N’ frame to the Savage defined ‘E’ frame. Encodes position/wander angle at the starting point of mechanization.

  • h0 – Height above ellipsoid at the start of mechanization, meters.

  • v_n_0 – Vector3 of X, Y, Z velocities in the Savage defined ‘N’ frame, m/s.

  • C_s_to_l_0 – DCM that rotates from the inertial sensor frame to the Savage defined ‘L’ frame at the starting point of mechanization.

  • mech_options – Mechanization options to use. This function only honors the grav_model and earth_model fields.

  • aiding_alt_data – Container holding an external altitude measurement in m HAE, the accumulated error resulting from the aiding the altitude in the inertial’s mechanization, and additional options for the aiding algorithm.

Returns

Tuple consisting of the post-mechanization position matrix, height, velocity and orientation DCM, following the same format as C_n_to_e_0, h0, v_n_0, C_s_to_l_0 respectively.