Optical Enhancement of Exoskeleton-Based Estimation of Glenohumeral Angles

In Robot-Assisted Rehabilitation (RAR) the accurate estimation of the patient limb joint angles is critical for assessing therapy efficacy. To address the said limitations in posture estimation, we propose installing the cameras of an optical marker-based MOCAP in the rehabilitation exoskeleton. Then, the GH joint angles are estimated by combining the estimated marker poses and exoskeleton Forward Kinematics.

• 1
  The results show that, even with significant errors in the marker position estimation, method accuracy is adequate for RAR.
• 2
  By averaging the results of all movement datasets, errors of 0.00110 mts and 0.88921 deg. in the upper arm position and orientation estimation are obtained.
• 3
  Even with marker drifts of 0.02 mts, the GH joint angles can be estimated with an accuracy (RMSE 3.6 deg.) appropriate for the mobility evaluation of patients