Switching PID Strategy for Positioning Systems with Non-Symmetric Friction and Noisy Velocity Measurements

This paper proposes a model-free, switching PID control strategy for point-to-point motion in positioning systems, where asymmetric friction and noisy velocity measurements are present. Traditional low-level control methods, such as PID, struggle with friction and noise in real-world conditions, particularly due to the difficulty in tuning parameters. The proposed approach employs a two-stage state-machine design to manage friction asymmetries and measurement noise, without requiring friction estimation or complex models. Experimental results on an industrial system demonstrate the approach's simplicity, robustness, and independence from system-specific parameters, offering a practical solution for high-precision, repeatable motion control in the presence of challenging disturbances.