Quaternion-based AHRS with MEMS Motion Sensor for Biomedical Applications

This work presents relevant theoretical and practical aspects towards the design of a quaternion-based real-time Attitude and Heading Reference System (AHRS). The motion sensor used in this work is the TDK InvenSense MPU-9250 9-degree (gyro + accelerometer + compass) Microelectromechanical system. Results show that the AHRS developed device is “gimbal lock” immune, given that the 3D rotations are performed in quaternions. The tiny electronic device allows real-time transmission of the 3D orientation and can be used as an AHRS solution for medical, sports science, rehabilitation and assistive technology. The contribution of this paper is a theoretical methodology and a practical implementation of an AHRS device for Biomedical applications.