Shortest Path Planning of UAV for Target Tracking and Obstacle Avoidance in 3D Environment

This paper focuses on planning the shortest path of the unmanned aerial vehicle (UAV) for tracking ground target under kinematics constraints, wind effects, and obstacle avoidance requirements in complex three-dimensional environment. First, the path planning mission is modeled in detail by formulating the UAV point-mass model, the target model, the obstacle model, etc. Then, the shortest path guidance vector field (SPGVF) is proposed to optimize UAV trajectory. According to the target motion information, the SPGVF algorithm can guide UAV to the optimal observation height in the vertical plane, as well as converge to the standoff distance along the tangent of the objective circle in the horizontal plane. Third, obstacle avoidance strategy is proposed to plan the collision-free path. By combining the SPGVF and obstacle avoidance strategy, the missions of tracking target and avoiding obstacles can be performed with the feasible shortest path simultaneously. Finally, the simulation results show that the hybrid method can generate the shortest path in various scenarios.