Robust Subsystem-based Impedance Control of Flexible Manipulator

Abstract

This paper proposes a Robust Subsystem-based Impedance Model Predictive Control (RSI-MPC) framework for the task-space control of flexible manipulators. Controlling flexible-link manipulators poses significant challenges due to their distributed dynamics, structural vibrations, and sensitivity to external disturbances. To address these issues, the flexible structure is modeled kinematically and dynamically as an open chain of rigid bodies. This formulation uses feedback from a network of Inertial Measurement Unit (IMU) sensors, enabling accurate state estimation while maintaining compatibility with real-time implementation in closed-loop configurations. Building on the approximated dynamic model of the open-chain system, the proposed RSI-MPC method ensures robust impedance behavior under model uncertainties and varying interaction conditions. Experimental results demonstrate that the RSI-MPC significantly improves the precision of interaction force handling while simultaneously generating smoother and lower-magnitude control inputs, validating its effectiveness in real-time manipulation tasks.