#if INERTIAL_NAV == ENABLED // generates a new location and velocity in space based on inertia // Calc 100 hz void calc_inertia() { // rotate accels based on DCM // -------------------------- accels_rotated = ahrs.get_dcm_matrix() * imu.get_accel(); accels_rotated += accels_offset; // skew accels to account for long term error using calibration accels_rotated.z += 9.805; // remove influence of gravity // rising = 2 // neutral = 0 // falling = -2 // ACC Y POS = going EAST // ACC X POS = going North // ACC Z POS = going DOWN (lets flip this) // Integrate accels to get the velocity // ------------------------------------ Vector3f temp = accels_rotated * (G_Dt * 100); temp.z = -temp.z; // Temp is changed to world frame and we can use it normaly // Integrate accels to get the velocity // ------------------------------------ accels_velocity += temp; } void z_error_correction() { speed_error.z = climb_rate - accels_velocity.z; accels_velocity.z += speed_error.z * 0.0350; //speed_correction_z; accels_velocity.z -= g.pid_throttle.get_integrator() * 0.0045; //g.alt_offset_correction; // OK accels_offset.z -= g.pid_throttle.get_integrator() * 0.000003; //g.alt_i_correction ; // .000002; // For developement only // --------------------- if(motors.armed()) Log_Write_Raw(); } void xy_error_correction() { // Calculate speed error // --------------------- speed_error.x = x_actual_speed - accels_velocity.x; speed_error.y = y_actual_speed - accels_velocity.y; // correct integrated velocity by speed_error // this number must be small or we will bring back sensor latency // ------------------------------------------- accels_velocity.x += speed_error.x * 0.0175; // g.speed_correction_x; accels_velocity.y += speed_error.y * 0.0175; // Error correct the accels to deal with calibration, drift and noise // ------------------------------------------------------------------ accels_velocity.x -= g.pid_loiter_rate_lon.get_integrator() * 0.007; // g.loiter_offset_correction; //.001; accels_velocity.y -= g.pid_loiter_rate_lat.get_integrator() * 0.007; // g.loiter_offset_correction; //.001; // update our accel offsets // ------------------------- accels_offset.x -= g.pid_loiter_rate_lon.get_integrator() * 0.000003; // g.loiter_i_correction; accels_offset.y -= g.pid_loiter_rate_lat.get_integrator() * 0.000003; // g.loiter_i_correction; } static void calibrate_accels() { // sets accels_velocity to 0,0,0 zero_accels(); accels_offset.x = 0; accels_offset.y = 0; accels_offset.z = 0; for (int i = 0; i < 200; i++){ delay(10); read_AHRS(); } for (int i = 0; i < 100; i++){ delay(10); read_AHRS(); calc_inertia(); Serial.printf("call accels: %1.5f, %1.5f, %1.5f,\n", accels_rotated.x, accels_rotated.y, accels_rotated.z); } accels_velocity /= 100; accels_offset = accels_velocity; zero_accels(); calc_inertia(); Log_Write_Data(25, (float)accels_offset.x); Log_Write_Data(26, (float)accels_offset.y); Log_Write_Data(27, (float)accels_offset.z); } void zero_accels() { accels_rotated.x = 0; accels_rotated.y = 0; accels_rotated.z = 0; accels_velocity.x = 0; accels_velocity.y = 0; accels_velocity.z = 0; } #endif