Design and Practical Implementation of a High Efficiency Two-Layer Trajectory Planning Method for AGV

This article proposes a two-layer trajectory optimization method for the autonomous ground vehicle. This two-layer strategy includes an efficient path planning layer and a fast trajectory planning layer. In the first layer, a novel target area adaptive rapidly exploring random tree algorithm (TAA-RRT*) is proposed to search the shortest path. This layer mainly includes a preprocessing and a sampling planning process. In the preprocessing process, the generalized voronoi diagram is used to construct the environment information and find the initial path. Then, the sampled target area (TA) is constructed based on this initial path to provide nonuniform sampling. In the sampling planning process, the improved adaptive RRT* algorithm is used to carry out sampling planning in the TA, and the direct connection strategy is combined to quickly locate the optimal solution. In the trajectory planning layer, combined with the constraints of the unmanned vehicle and the path constraints obtained in the first layer, the speed planning and the trajectory optimization are addressed by solving the optimal control problem. After performing a large number of experiments, the feasibility and effectiveness of the proposed method are verified.