Li Rongbing

Research on relative navigation algorithm for UAV Autonomous Aerial Refueling rendezvous phase

The lack of Autonomous Aerial Refueling capability is one of the greatest limitations of UAV (unmanned aerial vehicle). The estimation of the relative position, velocity and attitude is the key issue in this research area. This paper proposes a novel method for relative navigation. We focus on the need for the rendezvous phase. The structure of this paper is as follows. Firstly, we shall briefly introduce the autonomous aerial refueling phases and the related navigation sensors. Then we establish the error equation. After using the Kalman filter, we obtain the estimation of the relative state error. The employed algorithm based on the SINS/GPS/IRST integrated relative navigation, it has advantages of both autonomous navigation and passive target positioning. In simulation experiments, the results show that our algorithm can track the relative state variation and restrain the error divergency effectively.

Dynamic modeling and performance analysis of a hose-drogue aerial refueling system based on the Kane equation

This paper proposes a dynamic model and performance analysis method of hose-drogue aerial refueling system based on Kane equation by rigid multibody dynamics. In this method, the hose is divided into finite segment rigid joint of bars. To depict spatial state of each hose-bar, system generalized coordinates and generalized rates are defined. A set of multi-level recursive formulas and dynamic equations are derived to describe the dynamic properties of the hose-drogue under a prescribed motion of tanker. To calculate the external aerodynamic loads of each hose-bar, the effects of tanker wake, steady flow and atmospheric turbulence are considered. Numerical simulation results show a good correctness of the dynamic model by steady-state characteristics of the balance drag trajectory of hose-drogue in different flight conditions. Furthermore, the dynamic characteristics of the hose-drogue resulting from atmospheric turbulence are investigated.