|Fuzzy Control Strategy for Course Correction of Omnidirectional Mobile Robot
Niu Zijie*, Lu Qiang, Cui Yonjie, and Sun Zhijun
International Journal of Control, Automation, and Systems, vol. 17, no. 9, pp.2354-2364, 2019
Abstract : Omnidirectional mobile robots (OMRs) based on the Mecanum wheel, often slide during driving and cause the actual course to deviate from the set heading. To improve the OMR course accuracy, we propose a fuzzy
PI control algorithm that modifies the OMR course in real time, by analyzing the omnidirectional movement of the Mecanum wheel and the kinematic model of the OMR, fuzzification, fuzzy reasoning, and defuzzification, the robot’s heading is corrected in real time. Analysis of the yaw error of the robots, with and without the fuzzy PI control algorithm, show that the yaw error has been reduced from the original values of −2.5-0◦ and −10.5-0◦ down to −0.6-0.6◦ and −1-0◦ , when the robot travels a distance of 3.5 m in the longitudinal and transverse directions, respectively. Through experiments, the traditional PI control algorithm and fuzzy PI control algorithm are compared in terms of the robot heading-regulation performance. From the analysis of experimental data, we can see that, when the yaw error of an OMR with the fuzzy PI control algorithm is between 35 and 40◦, the adjustment time is sped up by 1.3 s and 1.2 s and overshoot angle is reduced by 7.7◦ and 4.3◦ , respectively, for longitudinal and transverse movements. Both experimental results show that the fuzzy PI control algorithm has good regulation performance and can achieve good control effects.
Course modification, fuzzy PI control, Mecanum wheel, omnidirectional mobile robot (OMR).