Collaborative control in a flying-boom aerial refueling simulation

Unmanned aerial systems are increasingly prevalent in the defense and civil sectors, and there is a desire to increase their effectiveness and versatility by adding the capability to perform air-to-air refueling. Furthermore, the burden on pilots can be significantly reduced by implementing automated flight control in refueling operations. Existing work on automated air-to-air refueling focuses on leader/follower architectures, which do not fully exploit all available control authority. This paper presents a collaborative control design that may be used to coordinate the flying boom and receiver aircraft. The control scheme is implemented in a refueling scenario modeled with a detailed air-to-air refueling simulation model. Results suggest that employing a weighted collaborative target point between the flying boom and receiver improves the docking time and reduces the susceptibility to disturbances because the errors for the tracking controllers are weighted by the displacement between the two objects. However, to maintain the docking in the operational envelope, a virtual structure is required to suitably anchor the target point.