Minoru Yokoyama, Tomoyuki Shimono, Satoru Nakamura
From the viewpoint of implementation, the simplicity and effectiveness of a control method are important factors for widespread adoption. This study presents a simple and intuitive method for bidirectional switching between position control and force control for robotic applications. To explicitly control position during free motion and interaction force during constrained motion, a cascade structure with an outer position controller, a switching controller, and an inner force controller is proposed. The switching controller comprises a saturation function to realize explicit force control and a compensator to restore position control performance. The stability of transitions between control modes is discussed within the framework of hybrid dynamical systems. Experimental results establish the validity of the proposed method.