Abstract
Conventional automatic trajectory tracking control technics for car-like ground vehicles typically decompose the controller into separate longitudinal driving control and lateral-directional steering control, owing to the nonholonomic kinematic constraint, highly nonlinear dynamics and control under-actuation of such vehicles. However, such decoupled control techniques inevitably impose operational constraints on agile maneuvers that may be critical in evading impending collisions, preventing loss-of-control of the vehicle, and special maneuvers that are needed for law enforcement missions. Thus, integrated three-Degree-of-Freedom (3DOF) tracking control of car-like ground vehicles are highly desirable but remains a challenging problem. There also appears to be a lack of research on automated reverse driving. In our previous work [ASME DSCC2017-5372, DSCC2018-9148], design and hardware validation test results of an integrated 3DOF trajectory tracking controller based on nonlinear kinematics and dynamics vehicle model using Trajectory Linearization Control (TLC) for forward driving have been reported. The present paper supplements that work with design and hardware validation test results on vehicle backward driving at fast and low speeds. The reverse driving control incurs minimal alteration to the original design with minimal tuning efforts due to the model-based TLC control approach, and it should be readily scaled-up to full-size vehicles and adapted to different types of autonomous ground vehicles with the knowledge of vehicles’ kinematics and dynamics parameters.