Optimization-based trajectory planning for reconfigurable unmanned vehicle units with multi-steering modes during the reconfiguration process

Reconfigurable unmanned vehicle unit (RUVU) exhibits three distinct steering modes: Ackermann steering, Diagonal steering, and In-Situ steering. This arises from its capacity for All-Wheel-Independent-Steering (AWIS) and All-Wheel-Independent-Driving (AWID). Given its unique motion characteristics, there is currently a lack of established methods to assist a RUVU in autonomously planning trajectories. In response to this deficiency, this paper proposes the Multi-Steering Modes Trajectory Planning algorithm (MSMTP) based on the framework of optimal control problem (OCP). The approach innovatively formulates the kinematics and Steering-Mode-Switch theory for vehicles with multi-steering modes. Additionally, a safe traveling corridor (STC) is implemented to guarantee non-conflicting interaction with the surrounding environment. Ultimately, the Bonmin solver is utilized to derive optimal results. Our findings demonstrate the effectiveness of the proposed algorithm in RUVU’s trajectory planning. When comparing the trajectory of RUVU to that of a vehicle only with Ackermann steering, the results also reveal that RUVU has the advantage of reaching its destination in a shorter time, especially in narrow environments.