Feedforward for multi-rate motion control: Enhanced performance and cost-effectiveness

In traditional feedback control, a single sampling rate is used for all control loops. Consequently, achieving higher performance by increasing the sampling rate is generally costly. The aim of this paper is to develop a multi-rate control framework to create a breakthrough in the performance/cost trade-off in digital controller implementation. In the proposed approach one of the control loops is implemented at a lower rate of which the feedforward controller is designed through norm-based minimalization of the tracking error in this multi-rate framework. By designing and implementing one of the control loops at a lower rate, the cost is reduced and the multi-rate problem is addressed. Through simulation the adequate performance of the proposed multi-rate approach is demonstrated.