TAF PUBLISHING

This paper presents a technique to reduce positional errors in redundant Wheeled Mobile Robots (WMRs) with omnidirectional wheels. The errors could originate from different resources during the process of design to fabrication of a WMR including modelling inaccuracy, backlash/joint deflection, and misalignment. The technique is explained based on the kinematic equations of WMRs, and could potentially be used to correct both the lateral and longitudinal errors observed during the movement of a non-holonomic mobile robot. The major advantages of this method are simplicity, time efficiency, and use of simple-to-understand kinematics equations. In addition, it uses the linear regression method – that is easy to use – to quantify the contribution of each wheel on observed errors. The effectiveness of the method was investigated by testing a prototype three-wheeled omnidirectional robot. According to the test results, the movements of the tested robot was improved, and the systematic errors decreased by at least 74%.