Progress in modeling and control of probe-and-drogue autonomous aerial refueling

By refueling aircraft while they are in flight, aerial refueling is an efficient technique to extend their endurance and range. Autonomous Aerial Refueling (AAR) is anticipated to be used to complete aerial refueling for unmanned aircraft. There are three aerial refueling methods: the Probe-and-Drogue Refueling (PDR) refueling method, the flying-boom refueling method, and the boom-drogue-adapter refueling method. The paper considers the PDR approach, the most challenging of the three, because the flexible hose-drogue assembly has fast dynamics and is susceptible to various kinds of winds, which makes the probe docking with the drogue difficult. PDR is divided into four phases, namely the rendezvous phase, joining phase, refueling phase, and reform phase, with the refueling phase being the most crucial. The controller design faces the greatest challenge during the docking control of the refueling phase since it calls for a high level of safety, precision, and efficiency. As a result, the modeling and control issues encountered during the refueling phase are typical and difficult. The fundamental idea of AAR is presented in the paper first, after which the characteristics and requirements of AAR are outlined. The progress in modeling and control techniques for the AAR's refueling phase is then systematically reviewed. Finally, potential future work for high safety, precision, and efficiency requirements is examined and suggested.