A mathematical model of the motion of an unmanned tractor with front steerable wheels during the ‘single lane change’ maneuver

BACKGROUND: The motion of an unmanned tractor can be represented in the form of elementary primitives, one of which is the ‘single lane change’ maneuver. Taking into account the kinematic limitations of a wheeled mover with front steerable wheels, it is necessary to calculate in advance the coordinates of the beginning of the maneuver depending on the magnitude of the displacement and the motion velocity for accurate and effective planning of the motion path. OBJECTIVE: Development of a mathematical model of the motion of an unmanned wheeled tractor with front steerable wheels when performing the ‘single lane change’ maneuver, obtaining analytical dependences of the length of the maneuver and the time of the control signal from the motion velocity and the required displacement value. METHODS: To achieve this aim, the mathematical model of the kinematics of the curvilinear motion of a wheeled tractor with front steerable wheels was developed. The description of the maneuver and possible motion paths are given. RESULTS: During the theoretical study, the dependences of the time of the control signal and the length of the maneuver were obtained, depending on the required amount of displacement when the tractor is moving at various velocities. The approximation of the obtained data made it possible to obtain analytical dependencies. CONCLUSIONS: The obtained dependencies can be used to control unmanned tractors with front steerable wheels at various displacement values and when moving at various velocities to perform the ‘single lane change’ maneuver clearly at specified waypoints.