Functional Shoulder Joint Modeling for Accurate Reach Envelopes Based on Kinematic Estimation of the Rotation Center

We developed a new method to estimate the functional center of rotation of the shoulder joint. Using this method, we examined the relationship between the posture of the upper arm and the displacements of the estimated center of rotation of the shoulder joint. The displacements were calculated from the flexion-extension angle and abduction-adduction angle of the upper arm. In this study, we propose a shoulder model for digital manikins that simulates reach envelopes more accurately than that for the existing digital manikins.