Equilibrium-Point Control and Robustness Analysis of Bioinspired Musculoskeletal Robotic System

Abstract

Compared to general joint-link robotic systems, bioinspired musculoskeletal robotic systems provide more potential advantages in terms of robustness, flexibility, and operation accuracy. Research on bioinspired control and structure has been a hot topic in recent years, indicating that musculoskeletal robots are a promising option for next-generation robots. However, standard modeling and analysis of the system are scarce; therefore, controller design and stability proof are still open questions. Based on previous studies, we built the standardized state-space equations for musculoskeletal robotic dynamics. The robustness was proved through muscle contractile dynamics and the Lyapunov stability theorem. Furthermore, a bioinspired equilibrium-point (EP) controller was designed to realize high-precision target-reaching tasks that required low control frequency and computation cost. Simulations and experiments were conducted to demonstrate the conclusions of the theoretical analysis. The effectiveness and anti-interference abilities of the EP controller were initially verified. This study provides a promising direction for motion control in bioinspired musculoskeletal robotic systems. A relatively complete system model was established, and a preliminary controller design and proof framework was proposed, which offers a reference for research and applications of musculoskeletal robotic systems.