Switching Control for a Soft Rehabilitation Glove With Pneumatic Bellows Actuators

This letter introduces a switching control method for a soft rehabilitation glove using pneumatic bellows actuators. The design and manufacture are introduced for the soft rehabilitation glove. A dynamic nonlinear system is established for deflection angles of finger joints when using the soft rehabilitation glove via an Euler-Lagrange modeling method. Inspired by active-disturbance-rejection-control method, the switching control method is designed for motion control of the soft rehabilitation glove based on tracking differentiators and extended state observers. Tracking differentiators are used to arrange transient processes for obtaining continuous smooth tracking signals and differential signals of each finger segment desired rotation angles. Extended state observers are used to estimate unknown states of the dynamic nonlinear system. Theoretical analysis are carried out for the estimation errors and tracking errors of the dynamic nonlinear system under the switching control method, the estimation errors and tracking errors are proved to be uniformly ultimately bounded. Finally, deflection angles control simulation is performed for finger joints when using the soft rehabilitation glove under the proposed switching control method.