Research on the Path Following Control of Intelligent Vehicle with Method of Added Planning Layer

Aimed at intelligent vehicles operating in complex driving environment, the paper is described on the basis that the reference trajectory has been determined. According to the vehicle running state and obstacle information, the vehicle's running track can be adjusted in real time to solve the path planning problem and according to the re-planned reference track, the following control is carried out in the paper to avoid obstacles. Firstly, a point mass model is established which ignores the car body size. Secondly, on the premise that the size of obstacles is smaller than the car body size, according to the obstacle information obtained by the sensor and the established point mass model, the obstacle avoidance penalty function is established, then the objective function of the path planner is established. Finally, two working conditions: single obstacle and two obstacles, are set up to simulate and verify the designed obstacle avoidance trajectory following system. By observing the distance between the actual track and obstacles under different simulated speeds, varied range of front wheel angle and centre of mass side deflection angle, different range of angular velocity of lateral swing and lateral acceleration to verify whether the vehicles can successfully avoid obstacles with different speed and numbers of obstacles in order to maintain good driving stability in the process. Simulation results show that, under the control of the path following system added to the planning layer, intelligent vehicles in a complex driving environment can autonomously plan their paths, avoid obstacles, follow the path, and ensure good driving stability meanwhile.