Active force control system for tremor suppression in elbow joint

Tremor is a neurological disorder characterized by involuntary oscillations. Difficulties associated with tremor in patients with Parkinson's disease have motivated the researchers to work on developing various methods for tremor suppression. Active Force Control (AFC) method for tremor attenuation in human body parts is considered in this work. This paper proposes a new AFC system based on a piezoelectric actuator. A one-degree-of-freedom musculoskeletal model of the elbow joint with two links and one joint is developed. The model includes two muscles, biceps, and triceps as the flexor and the extensor of the elbow joint. First, simulation of the tremor generation in the model is performed and then the performance of AFC system for suppressing elbow joint tremor is investigated. A single piezoelectric actuator is embedded in AFC system for controlling the behaviour of the classic proportional-derivative controller. MATLAB Simulink is used to analyse the model. Results show that the AFC-based system with a piezoelectric actuator and a PD controller is very effective in suppressing the human hand tremor.