A simple nonlinear velocity estimator for high-performance motion control

Based on the fact that numerical integration can provide more stable and accurate results than numerical differentiation in the presence of noise, a constructive nonlinear velocity estimator (NVE) with simple computation is developed for high-quality instantaneous velocity estimation, based on the position measurement only. The attraction of the new velocity estimator is that it is very effective as well in the low-velocity ranges, it has high robustness against noise and design parameters, and it is easy to implement. Furthermore, the developed approach is model free. Both simulation and experimental tests have been run to verify its effectiveness and efficiency. The proposed new simple NVE has built a solid base for high-performance control of servo systems.