Design of a variable resistance training system using rotary magneto-rheological brake

In literature, variable resistance exercises have reported as a rehabilitation for motor improvement in cerebellar/extremity ataxia. In this study, a new rehabilitation device has been designed for training ataxic patients for developing upper extremity functions. In order to provide coordination muscle exercises, circular movements with different resistance patterns have been suggested. The designed device is setup of a rotary magneto-rheological brake (MR), force sensor, and a brace. Pulse width modulation (PWM) scheme has been proposed as a simple control technique to generate MR brake current relating to the selected reference resistance pattern. The experimental results have been discussed.