A simple improved velocity estimation for low-speed regions based on position measurements only

High-quality low-speed motion control calls for precise position and velocity signals. However, velocity estimation based on simple numerical differentiation from only the position measurement may be very erroneous, especially in the low-speed regions. A simple efficient high-quality instantaneous velocity estimation algorithm is developed in this paper, by using the position measurements only. The proposed estimator is constructed based on the fact that numerical integration can provide more stable and accurate results than numerical differentiation in the presence of noise. The main attraction of the new algorithm is that it is very effective as far as in low-speed ranges, high robustness against noise, and easy implementation with simple computation. Both extensive simulations and experimental tests have been performed to verify the effectiveness and efficiency of the proposed approach.