Safe High Stiffness Impedance Control for Series Elastic Actuators using Collocated Position Feedback

Physical human-robot interaction applications requiring safety and compliance characteristics usually employ mechanical devices such as series elastic actuators (SEAs). So far, impedance control schemes for SEAs have been investigated to overcome the limited displayable stiffness at end point, represented by of a physical spring, in passive manner. mount two encoders on both motor load sides position measurements. However, several applications, installation load-side encoder is not feasible from cost manufacturing perspectives. In this scenario, Kalman Filter based micro electro system accelerometers has proposed estimating external force side quantities, without need encoders. Herein, novel scheme leveraging approach effectively spring while maintaining passivity point. Compared with conventional encoder-based schemes, presents comparable performance, demonstrated simulation experimental results.