Exponential predefined-time spatial–temporal cooperative guidance method with obstacle avoidance

This paper investigates the cooperative guidance problem with effective obstacle avoidance considering spatial–temporal constraint. A novel cooperative guidance methodology is presented to make multiple flight vehicles not only attack the target with desired Line-of-Sight (LOS) angle intervals simultaneously, but also avoid the obstacle safely. First, we design the temporal cooperative guidance law along the LOS direction to meet the requirement of the simultaneous arrival, and present the lateral cooperative guidance law by utilizing the errors of the bias LOS angles to form the desired angle intervals. Then, the constraints of impact time and LOS angle are considered in the spatial–temporal cooperative guidance law. To achieve obstacle avoidance, an additional obstacle avoidance acceleration command is derived. This command leverages real-time measurements of both the distance and the relative orientation between each flight vehicle and nearby obstacles, generating repulsive maneuvers as needed. Finally, weighting coefficients, dynamically adjusted based primarily on the proximity to obstacles, are introduced to optimally blend the cooperative guidance acceleration components and the obstacle avoidance acceleration components. This allows the flight vehicles to prioritize obstacle evasion when critically close, while seamlessly resuming coordinated flight towards the target when safe, achieving spatial–temporal coordination and robust obstacle avoidance concurrently. Both theoretical analysis and numerical simulation demonstrate the effectiveness and robustness of the presented cooperative guidance approach.