Auto-Calibration of Bias Compensated 2D-Mounting Orientation of an IMU on an Electric Bicycle Using Bike-Specific Motions

The strong increase of electronically power assisted cycles (EPACs) and the progress in the development of electric bicycles lead to an increasing amount of inertial measurement unit (IMU) -based use-cases for EPACs. One requirement for such use-cases is a calibrated orientation of the IMU on the EPAC. The approach presented in this paper uses bike-specific motions to calibrate a 2D-mounting orientation of a micro-electrical-mechanical-system (MEMS) IMU. The method is independent of sensor biases and requires only a small amount of computations. The results show high accuracy of the calibrated orientation during the experimental testing with an EPAC.