Segmented hybrid impedance wave based control for hyper-redundant space manipulators

Hyper-Redundant Space Manipulators (HRSMs) have become a pivotal solution for space operations, offering a safer and more economical alternative to the risks and costs of astronaut-led extravehicular activities. Initially designed to navigate and avoid obstacles, these manipulators have advanced significantly, now capable of actively interacting with their environment. However, traditional control methods face significant challenges in managing multiple contact points, often compromising stability in the dynamic and unpredictable conditions of microgravity. To address these limitations, this paper proposes a novel segmented hybrid impedance wave-based control strategy for HRSMs operating in multi-contact environments. Integrating wave-based control with hybrid impedance control, this approach leverages mechanical flexibility and bidirectional wave propagation to enable robust management of multiple contact points, effectively mitigate sensor noise, and ensure smooth transitions in contact forces. The wave-based control framework simplifies implementation by reducing the need for complex system modeling while simultaneously achieving precise position control and active vibration damping. The full non-linear dynamics of the HRSM system are modeled using Kane's method, accounting for both free-space motion and constrained operational phases. Extensive numerical simulations validate the proposed strategy, demonstrating its effectiveness in maintaining stable multi-point contact interactions and absorbing residual vibrations and outperforming the impedance control architecture. These results underline the potential of the proposed control strategy to enhance the reliability and performance of HRSMs, paving the way for advanced applications in space robotic operations.