Path Planning of Multiple AGVs Using a Time-space Network Model

Path planning of Automated Guided Vehicles(AGVs) is critical for the material handling in manufacturing and warehouses. For collision-free path planning of AGVs, this paper proposes a new time-space network model which combines an minimal time objective with the constraints of time and space. First of all, the paper gives an optimal mathematical model to plan the shortest time path to complete a number of tasks for AGVs. The space constraints are added to resolve vehicle collision on the basis of the shortest path. Time constraints are added to make the AGV correspond to its space and time states when moving. In this way, the state of the AGV can be obtained to plan the optimal path. In order to verify the validity of the proposed method, collision avoidances of the proposed planning method are demonstrated with an example of three AGVs working at the same time. The results show that this method could be used to plan non-conflicting paths for AGVs when working simultaneously and to achieve the shortest time path. It can be found that the total time can be optimized by changing the running time of the AGV.