Safety in Admittance Control using Reference Trajectory Shaping
This work addresses safety and compliance issues in human-robot interaction, which is incremental as it builds on existing admittance control methods with added safety guarantees.
The paper tackled the problem of ensuring safety and compliance in human-robot collaboration by proposing a switched model reference admittance control framework with reference trajectory shaping, achieving asymptotic convergence of tracking error and validating effectiveness through simulations and real-time implementation on manipulators.
This paper presents a switched model reference admittance control framework to achieve safe and compliant human-robot collaboration through reference trajectory shaping. The proposed method generates variable admittance parameters according to task compliance and task-space safety requirements. Additionally, a disturbance bound is incorporated to enhance robustness against disturbances. Safety guarantees are explicitly established by integrating invariance control, ensuring that the reference trajectory remains within the admissible region. Stability of the switched system is analyzed using a common quadratic Lyapunov function, which confirms asymptotic convergence of the tracking error. The effectiveness of the approach is demonstrated through simulations on a two link manipulator and comparisons with existing methods are also presented. Furthermore, real time implementation on a single link manipulator validates the practical feasibility of the controller, highlighting its ability to achieve both compliance and safety in physical interaction scenarios.