Delayless differentiation algorithm and its efficient implementation for motion control applications

Abstract

Acceleration feedback can improve the performance of motion control in motor drives. Acceleration control is, however, seldom implemented in practical drive systems due to the unsatisfactory results of most acceleration measurement methods. In this paper, we introduce a computationally efficient (Finite Impulse Response) filter-based algorithm which makes it possible to differentiate the polynomial-like velocity signal with optimal white noise attenuation. The proposed signal processing algorithm does not delay the acceleration signal but, instead, the prediction step can be freely adjusted to compensate for various delays in the physical implementation. Our algorithm can be implemented by utilizing recursive structure so that the amount of multiplications and additions required does not depend on the filter length. No additional hardware is required to implement the algorithm because it can be programmed as part of the control software. The performance of the new algorithm is evaluated by applying it to a simulated motion control application.