A Three-Channel Control Scheme with Force Estimation for Transparency and Stability Improvement in Bilateral Telerobotic Systems

Abstract

This research proposes a three-channel control scheme to improve transparency and stability in nonlinear bilateral telerobotic systems. The control framework emphasizes position tracking and synchronization, with an unknown input observer estimating the external force exchanged between the environment and the slave robot. This estimated force signal is incorporated into the master robot's controller to achieve the design objectives. Specifically, the control approach addresses three primary goals: (1) position tracking and synchronization; (2) enhanced transparency through accurate force refection; and (3) stability analysis of the telerobotic system. The system architecture, structured as a three-channel bidirectional design, leverages the observer-based control law to ensure that position tracking errors remain stable. Ultimately, the performance of the proposed control scheme is validated on a nonlinear bilateral telerobotic system, demonstrating its potential to enhance both stability and transparency in real-world applications. Copyright © 2025 The Authors.