On-line denoising of motor speed control loop using order statistics filtering

In real-time motor speed measurements and control, severe noise spikes cause unacceptable performance degradation of the control loop. In this work, we propose a real-time filtering mechanism to reduce the unwanted effects of spiky noise. A Hardware-In-the-Loop (HIL) experimental setup was used to measure the noisy motor speed and an online order statistics filtering was applied to mitigate the effect of the noise. We tested and evaluated experimentally several orders of the applied on-line filtering algorithm. We showed that larger windows tend to enhance the smoothness of the response but at the expense of extra delay that can lead to oscillatory responses when a feedback controller is used. For the implemented system, we showed experimentally that a window size of 5 samples achieves a good compromise between impulsive noise rejection and acceptable oscillatory response.