Calibration of Motors for a Mecanum Platform

Mecanum mobile platforms offer high maneuverability in confined spaces, making them widely used in industrial automation as well as educational and research applications. However, their over-actuated nature necessitates precise motor synchronization to prevent slippage and ensure accurate motion execution. In this study, as a significant step in the development of our custom-designed and manufactured four-wheeled mecanum platform, we present a control method to effectively control the brushed DC motors used in the system. The platform incorporates four easily accessible brushed DC motors, each exhibiting unique characteristics (heterogeneous motor structure). Each motor undergoes individual calibration to determine its dead regions, and a PWM-RPM mapping is established. Encoder data is processed to estimate wheel speed, and a cascaded control architecture is implemented. Additionally, the proposed approach ensures robust performance by dynamically adjusting control gains as battery voltage decreases. The developed controllers have been validated through experiments on the real system.