Limiting Control and Accurate Observation of Transmission Torque and Its Jerk in Elastic Servo Systems

To enhance the transmission safety and accuracy of the servo system, this article comprehensively designs the control loops for transmission torque and its jerk, and innovatively explores a steady-state Kalman filter (SSKF) suitable for transmission control. First, this article proposes a design method for the transmission torque loop that considers both stability and compliance, and provides the controller parameter range and tuning rules. The proposed method does not rely on reference signals, offering a degree of general applicability. In addition, to address the issue of speed overshoot and oscillation caused by transmission state limits, a proportional–integral speed controller based on the antiwindup technique is designed. Next, this article proposes a higher order SSKF based on a constant jerk model to accommodate the transmission state feedback required in the studied cascade loop. Through stability analysis, the range and tuning rules of the observer's single adjustable parameter are determined, meeting both observation and control requirements (a tradeoff between smoothness and responsiveness). Compared to existing research on observers in transmission states cascade loop, the designed SSKF offers advantages such as high observation accuracy, low computational complexity, and ease of adjustment. Both simulations and experiments confirm the excellent transmission performance of the designed servo control structure and the observational capabilities of the SSKF. Furthermore, experimental comparison with the reference planning method verifies the precise tracking performance of the proposed control method for transmission torque and jerk.