Fuzzy systems for slippage control of a pruning robot

For a mobile robot using an encoder to measure the travel distance, a critical cause inducing the error is the slip of the wheel. The slippage not only causes the distance error, but also increases the overall energy consumption and decreases the locomotion performance. To cope with these effects without spending extra sensors or high processing load, the slippage control system composed of two fuzzy modules, namely the trajectory estimator and velocity controller, has been developed based on experimental data collected from encoders and a motion capture system. The control system applied the cross-coupling control technique by employing the estimated velocity from the estimator as a part of an input for the velocity controller of four wheels. This way, the simple yet effective slippage control system is feasible. Promising results verify the potential of the system. Thus, this initial research provides the framework to develop the competent slippage control system for our pruning robot.