Lyapunov Controller for an Agricultural Four-Wheel Independent Mobile Robot = Lyapunov Controller for an Agricultural Four-Wheel Independent Mobile Robot

다국어 초록 (Multilingual Abstract)

Due to their improved maneuverability in narrow spaces and increased stability, four-wheel independent mobile robots are becoming popular in several fields, such as agriculture, electrical vehicle, and planetary exploration. However, control algorithms are complicated owing to synchronization issues, mechanical constraints, and actuators equipped. This paper explores the kinematic model of a 4 wheel independent steering robot and make use of a Lyapunov controller and A-star planner for navigate a low velocity autonomous agricultural vehicle built on a 4 wheel independent steering configuration. The experiments were conducted in an even surface and the robot was equipped with incremental encoders for the driving motors and absolute encoders for the steering motors as well as a GPS TDR-3000 and a IMU LPMS-IG1 for navigation. Uneven terrains or obstacles were not considered for the experiments. The results show the capability of the controller to navigate the 4 wheel independent steering robot and reach the desired goals. In future, a local planner will be considered for obstacle avoidance and complex field experiments will be conducted in conditions of wheel slippage and low surface friction.