Musculoskeletal Modeling and Simulation of the Human Arm in Rehabilitation by Shoulder Wheel Device Using an Adaptive Robust Control Scheme

Shoulder pain is one of the most common musculoskeletal pains among patients. Rehabilitation is the key to getting the shoulder back to its original position. The shoulder wheel device is one of the shoulder rehabilitation devices that a patient can rotate it in the sagittal plane. In this study, the musculoskeletal modeling and simulation of the human arm rehabilitation in the sagittal planar motion by a shoulder wheel device are studied. The end-point of the patient's arm on the shoulder wheel device follows a specific path. Desired trajectories of the shoulder and elbow joints are obtained using inverse kinematics. Optimal muscle forces are obtained using static optimization based on the Lagrange's coefficients method. Also, the adaptive nonsingular fast terminal sliding mode (ANFTSM) controller is provided to control the end-point of the human arm on the path of the shoulder wheel device by taking into account uncertainties and disturbances. Eventually, numerical simulations are presented to show the results of the static optimization problem of the muscle forces and the performance of the ANFTSM controller as the human nervous system to generate control signals in the presence and absence of uncertainties and disturbances.