Kalman filter based equivalent elastic force feedback for time-delay compensation

This research proposes a Kalman filter-based equivalent elastic force feedback approach for time-delay compensation. This research shows that the time-varying delay can be regarded as noise in the input and output signals. In order to achieve robustness, this research proposes a Kalman filter-based state observer (KFSO) in the time-delay system for the estimation and the compensation of the disturbance forces without enhancing the effect of the time-varying delay. Furthermore, the state variables estimated by the KFSO are combined with the equivalent elastic force feedback in the time-delay system in order to improve the stability. Although the robustness of conventional time-delay compensation methods deteriorate during disturbances, the proposed method can retain stability while maintaining the robustness without enhancing the noise effects caused by the time-varying delay. The proposed method is validated by experimental results.