力の護り：未知環境との相互作用における安全臨界コンプライアント制御
Guarding Force: Safety-Critical Compliant Control for Robot-Environment Interaction
未知環境との接触時に力制約を厳密に守るため、力制約制御バリア関数と二次計画法を組み合わせたコンプライアント制御手法を提案し、UR3eロボットで有効性を検証した。
著者: Xinming Wang, Jun Yang, Jianliang Mao, Jinzhuo Liang, Shihua Li, Yunda Yan
分類: cs.RO
原文アブストラクト
In this study, we propose a safety-critical compliant control strategy designed to strictly enforce interaction force constraints during the physical interaction of robots with unknown environments. The interaction force constraint is interpreted as a new force-constrained control barrier function (FC-CBF) by exploiting the generalized contact model and the prior information of the environment, i.e., the prior stiffness and rest position, for robot kinematics. The difference between the real environment and the generalized contact model is approximated by constructing a tracking differentiator, and its estimation error is quantified based on Lyapunov theory. By interpreting strict interaction safety specification as a dynamic constraint, restricting the desired joint angular rates in kinematics, the proposed approach modifies nominal compliant controllers using quadratic programming, ensuring adherence to interaction force constraints in unknown environments. The strict force constraint and the stability of the closed-loop system are rigorously analyzed. Experimental tests using a UR3e industrial robot with different environments verify the effectiveness of the proposed method in achieving the force constraints in unknown environments.
