Modeling and Simulation of a Four-Wheel-Steered Agricultural Robotic Vehicle

摘要

A four-wheel-steered (4WS), four-wheel-driven (4WD) small agricultural robotic vehicle (AgRV) is under development in Agricultural Robotics Laboratory at the Iowa State University. This paper presents the modeling of a 4WS/4WD AgRV platform to assessits dynamic behavior and stability through simulation. The simulation was implemented using Matlab?Simulink and SimMechanics toolboxes. The vehicle was simulated considering three translational and three rotational degrees of freedom of the vehicle body.The steering performance of the vehicle for better maneuverability was studied using coordinated, crab and conventional steering systems. In the developed model, side slips, lateral acceleration of the vehicle, slip angle and the lateral force generatedon each of the four wheels during the simulation were analyzed for the dynamic stability evaluation of the vehicle. The extensive modeling and simulation of the vehicle will aid the design and finally the development of an AgRV navigational controller.