2D path control of four omni wheels mobile platform with compass and gyroscope sensors

Abstract

A four omni wheels platform was designed and constructed as the basis of a mobile robot. Liner bushing and spring is integrated with omni wheel supporting stand to construct each wheel simple suspension system. It can make sure that four wheels can always contact with uneven ground surface for avoiding wheel slipping or idle running. Electronic compass and gyroscope sensors are built in to measure the mobile platform azimuth and feedback for platform orientation control. Different filters are employed to handle those measured data signals processing for sensors fusion implementation. The distributed intelligent control algorithm is designed with each wheel rotation local control and the platform motion path motoring central control. Each omni wheel has a intelligent fuzzy sliding mode controller (FSMC) for rotation speed control. A central velocity compensator was designed to adjust four wheels speed based on compass or gyroscope orientation feedback for path navigation. Experimental results show that this embedded control system structure can improve the mobile platform moving path accuracy and reduce the influence of uneven surface or wheel idle spinning.