A CALIBRATION PROCEDURE FOR MIMU SENSORS ALLOWING FOR THE CALCULATION OF ELBOW ANGLES

Abstract

Non-optical wearable sensors such as magnetic and inertial measurement units (MIMUs) are gaining popularity in sport and clinical settings owing to their ease of application, relative affordability and potential for improved ecological validity. We propose a method for the standardised reference calibration of a simple two-sensor MIMU system for the estimation of anatomically meaningful elbow kinematics. The participant poses with the elbow at 90° flexion and neutral (0°) pronation, allowing for the relative orientation of the MIMU on the forearm to be determined with reference to the MIMU located on the arm. Comparisons were with traditional kinematic marker method results. Root mean squared errors of less than 1° in flex/ext and < 2° (pro/sup) found in simple movements. Results with simple movements provide rationale to expand research to complex movements.