Lyapunov-Based Thrusters’ Selection for Spacecraft Control: Analysis and Experimentation

摘要

This paper introduces a method for spacecraft rotation and translation control by on–off thrusters withnguaranteedLyapunov-stable tracking of linear dynamicmodels. In particular, the proposed controlmethod switchesnon, at each time step, only those thrusters needed to maintain stability. Furthermore, the strategy allocates thenconfiguration so that the minimum number of actuators is used. One of the benefits of the proposedmethod is that itnsubstitutes both the thruster mapping and the pulsemodulation algorithms typically used for real-time allocation ofnthe firing thrusters and for determining the duration of the firing.The proposed approach reduces the computationalnburden of the onboard computer versus the use of classical thruster mapping algorithms, which typically involveniterativematrix operations. The paper presents analytical demonstrations, numerical simulations on a six-degree-of-nfreedomspacecraft, and experimental tests on a hardware-in-the-loop three-degree-of-freedomspacecraft simulatornfloating over air pads on a flat floor. The method proves to be effective and easy to implement in real time.