Dual Position Feedback-Based Oscillation Suppression Method for Full Closed-Loop Position Control

Abstract:
In robotic joint servo systems, Harmonic Drives are extensively utilized owing to their high reduction ratios and zero-backlash properties. Nevertheless, the structural compliance of the flexspline introduces elastic deformation between the motor output and load ends, resulting in positional deviations and resonant oscillations that degrade control performance. To address these challenges, this study establishes a full closed-loop control architecture by integrating a load-side position sensor for direct feedback of the end-effector position. Furthermore, a dual-position feedback control strategy is proposed to suppress oscillations in the closed-loop system. The method synergistically processes motor-side encoder data and load-side positional measurements through dynamic compensation, effectively mitigating resonance induced by mechanical flexibility while preserving trajectory tracking accuracy.