Abstract:Reset control is known to be able to outperform PID and the like linear controllers. However, in motion control systems, quantization can cause severe performance degradation. This paper shows the application of time regularization to mitigate this practical issue in reset control systems. Numerical simulations have been conducted in order to analyze the cause of the quantization induced performance degradation and the effectiveness of time regularization to mitigate this degradation; with tuning guidelines for the time regularization parameter also provided. Moreover, a robustness analysis is performed. The solution is also tested experimentally on a high precision motion system for validation. It is estimated by numerical simulations that time regularization can reduce quantization induced performance degradation by almost 10 dB. Experiments have similarly shown a reduction of several dB for the high precision motion stage.
Abstract:Reset control has emerged as a viable alternative to popular PID, capable of outperforming and overcoming the linear limitations. However, in motion control systems, quantization can cause severe performance degradation. This paper investigates this degradation in practical systems and re-purposes the reset band condition in order to mitigate the same. Numerical simulations have been conducted on a mass based positioning system to analyze the cause of the quantization induced performance degradation. Moreover, a performance and robustness analysis was performed with the proposed solution. Finally, novel tuning guidelines are provided for estimating the required reset band parameter. Additionally, practical experiments have been conducted on a high precision motion system for validation. The experiments show by example that the reset band can reduce the error in the problematic region by up to 285% and hence shows the need and effectiveness of the proposed solution.