Control structure interaction analysis of the International Space Station

Abstract

In this paper, the interactions among the various subsystems that constitute the International Space Station (ISS) are analyzed and their impact on the performance of the attitude control system (ACS) is determined. The integrated ISS system consists of the flexible ISS structure, ACS, rotary joints (RJ), and the Mobile Transporter (MT). Control structure interaction (CSI) and controller-controller interaction (CCI) analyses are performed using linear models of the ISS and associated controllers. Several different operating scenarios are analyzed to assess the performance of the integrated system. Numerical results show that the effect of the interactions on the stability of the integrated system is minimal. The ACS and MT control systems satisfy stability design guidelines. The system stability is affected most by the solar array and thermal radiator rotary joint controllers. The integrated system performance is not significantly affected due to MT translations or small angle reorientations of the ISS and rotary joints.