Output feedback elliptical orbital rendezvous via state‐dependent Riccati differential equations

This article studies spacecraft rendezvous with the target spacecraft in an arbitrary elliptical orbit. Based on the linearised Tschauner–Hempel equations, state‐dependent Riccati differential equation (RDE)‐based approaches are proposed to solve the problem. An observer‐based output feedback controller is established. To implement the proposed controller, only some forward‐type RDEs need to be integrated online, indicating that the controllers can be implemented online as long as some positive‐definite initial conditions are given. Moreover, it is shown analytically that the closed‐loop system under the proposed feedback controller is exponentially asymptotically stable. Numerical examples show the effectiveness of the proposed approach.