Chapter 2 New for OEM7 – FirmwareOEM6 to OEM7 Integration Guide v1 153SETINSPROFILE LANDThe currently selected profile option is available in the INSCONFIG log.RBV CalibrationFor the profiles to provide the greatest benefit, the rotation offset of the IMU body to the vehicleframe (RBV) should be known as accurately as possible. Since constraints happen at the vehiclelevel, any error in the offset will translate into worse performance. These parameters are estim-ated in the background when the system is fully converged, however it is always better to havethis measured as precisely as possible before mission critical data is collected.The INSCALIBRATE RBV functionality can be used to estimate and save these offsets to NVM in acontrolled manor.2.4.8 Multi-Line Body to Vehicle Frame Rotation Calibration RoutineThe single pass Body to Vehicle frame offset calibration feature assumes flat ground when estim-ating the roll offsets between the IMU Body and Vehicle frames, as this component of the rota-tional offset is difficult to observe through typical ground vehicle motion. In practice this canresult in an outstanding roll offset error as high as several degrees. For applications wherevehicle roll must be well known, or pass-to-pass accuracy of a highly offset position is especiallyimportant, the Multi-Line IMU Body to Vehicle frame offset calibration routine offers higher cal-ibrated accuracy in roll. This is done by running independent calibrations over the same groundpath in opposite directions; averaging the results cancels out the effect of any terrain inducedroll. A minimum of two iterations are required. Additional iteration pairs can be executed forincreased reliability.Figure 1: Multi-Line IMU Body to Vehicle Calibration
