Design of a series elastic resistance mechanism for exercise and rehabilitation

This paper introduces an initial investigation of a series elastic resistance mechanism for exercise and rehabilitation. The idea of Series Elastic Actuator is applied to a resistance mechanism that is designed to perform stable force control under safe operation in a cost effective way. The mechanism can generate various resistance force considering the biomechanical characteristic of a human by actively controlling resistance during an exercise stroke. As an initial investment of a series elastic resistance mechanism, a prototype hardware has been developed. Bluetooth communication is used to connect the prototype with a smartphone which sets resistance levels and receives experimental data log. A PID feedback controller is implemented with the prototype hardware to provide a constant, non-inertial resistance force by maintaining a constant deflection of springs during an exercise stroke. Dynamic simulation and experimental results of the prototype are also presented.