DEVELOPMENT OF A FUZZY LOGIC CONTROLLER FOR AUTONOMOUS FOREST PATH NAVIGATION

Abstract

We describe the application of fuzzy logic to the control of a robot intended to navigate forest paths. Robots couldimprove the safety of forest operations by removing the operator from the vehicle and also reduce costs by automating theseoperations. The controller was organized into three modules, each of which was capable of providing a headingrecommendation for the robot. Sensory information was provided by shaft encoders and three ultrasonic rangefinders. Thecontroller required a set of sensory data acquired from one training run down the path. Two of the modules provided headingrecommendations from the shaft encoder and ultrasonic rangefinder data, respectively. A third module arbitrated therecommendations of the first two modules and provided a final heading recommendation. Decisions made by the operatorduring the training run were used in the arbitration to weight the recommendations of the individual modules. It was observedthat the combination of modules performed better than the individual modules alone. Despite the simplicity of the controller,a test vehicle was able to consistently navigate 152 m (500 ft) down a forest path. It was concluded that the approach isfeasible, and further development of the control algorithm is warranted.