Inverse Kinematics Analysis of Forearm in CPM Based on Biomechanics

Continuous passive motion (CPM) is a surgical treatment or physiotherapy after operations for disorders. In the rehabilitation with the CPM device for the upper limb, because the musculoskeletal structure of the upper limb is not clarified, the relationships between the upper limb joint and CPM are not analyzed. Especially, the joint angle information by accompanying pronosupination of the forearm is not clear. In this paper, a method using the wrist direction vector for calculating inverse kinematics of the forearm is proposed and applied to pronosupination model based on the biomechanics. In addition, the results are verified by comparing with the measure result of the forearm.