Abstract:

Path planning of multiple Automated Guided Vehicles （AGVs） in intelligent garage directly affects the efficiency and security of the vehicle. For the task execution priority of AGVs in RIG， the Improved Conflict-Based Search with priority （iCBS-pri） path planning model is proposed. The improved model is mainly composed of Task Allocation （TA）， single-AGV Path Planning （PP）， multi-AGV Conflict Detection and Resolution modules. The TA module allocates unassigned tasks to AGVs. The PP module improves the completion efficiency of AGV tasks by setting a linear penalty function to reduce the impact of the number of turns of the path on AGV running time. The CDAR module includes Conflict Detection （CD） submodule and Conflict Resolution （CR） submodule. The CR submodule develops conflict resolution policies based on Spare Zone （SZ） and Bypass planning （BP） for the conflict types detected by the CD submodule， so as to plan multi-AGV conflict-free routes. Simulation experiments verify the model under typical scenarios. The results show that： （1） Compared with the traditional A* algorithm， the improved A* proposed by the PP module reduces the path length and the number of inflection points by 8.82% and 38.62%， respectively； （2） The assignment success rate of the task allocation algorithm reaches 100%， with the task consistency probability reaching 88.9%； （3） Compared with the iCBS algorithm， the success rate of task planning of iCBS-pri algorithm is improved by 11.3% on average， with the average running time of the algorithm improved by 5.93%， which further improves the efficiency of RIG access vehicle.

Key words: intelligent garage, path planning, task execution priority, autonomous guide vehicle, conflict