The Computation of Desired Ball Velocity after Striking Based on Self-tunning Fuzzy Algorithm for Robotic Table Tennis
基于模糊自调节算法的乒乓球机器人回球速度计算

A model of computing the desired velocity of returning balls is developed so that the robot could return the incoming ball to a desired point on the table with a specified landing velocity. Firstly, three polynomials of the flying time are used to fit the ball's trajectory while neglecting the effort of the Magnus force; the initial velocity is obtained after the coefficients of the polynomials are estimated using LM algorithm. Then, a new configuration of storing and replacing experimental data is introduced; the result is received by fitting the stored data. The weighted average of the two results is regarded as the original value of the fuzzy correcting algorithm. With the analysis of the influence of the desired velocity on the error between the actual landing point and the desired point, the velocity is tuned using the fuzzy algorithm after the landing point is predicted. The tuned velocity is the eventual result for controlling the striking speed and posture of the paddle in the process of returning the ball. Finally, experiments were well conducted to verify the performance of the proposed method.