Comparison of Joint Angle Measurements from Three Types of Motion Capture Systems for Ergonomic Postural Assessment

Abstract

Observational ergonomic postural assessment methods have been used to evaluate the risks of musculoskeletal disorders. Recently, researchers have actively proposed semiautomatic approaches using motion capture data. This study compared joint angle measurements from optical, inertial, and depth-based motion capture systems, especially for cases with occlusions. Participants performed 6 static postures with different degrees of occlusion while capturing motion data by three motion capture systems. Results showed that the joint angle difference between the three systems was acceptably low in general, but the difference between Kinect and the other two systems was larger, especially in cases with occlusions. The findings indicate that the Kinect-based system is less stable than optical and inertial-based motion capture systems, but it can be used for ergonomic postural assessments in the environment without severe occlusions.