A Low Fuel-Consumption Drag-Free Tracking Approach for Space-Based Gravitational Wave Detection Satellite

The space-based gravitational wave (GW) detecting satellite's drag-free control system contains two test masses (TMs), and the relative translational motion between the three is coupled. Unlike the conventional single TM drag-free satellite, the double TMs drag-free satellite in GW detection cannot track the two TMs simultaneously with six relative translational degrees of freedom. Therefore, a suitable drag-free tracking approach is necessary to be chosen between the satellite and the two TMs to meet the residual acceleration demand in the direction of the TMs’ sensitivity axis. Different drag-free tracking techniques correspond to various decoupling feedback techniques, which result in various control performances between two TMs and a corresponding impact on fuel consumption. First, a new virtual point tracking approach that offers several possibilities for choosing drag-free reference points is provided after analyzing the virtual point tracking strategy used by the double TMs GW detection satellite. The position of the fuel optimal reference point is then determined. Additionally, the proposed tracking approach can reduce fuel consumption by about 15.8% at the fuel optimal reference point, and the results of the numerical simulations demonstrate excellent agreement with our hypothesis. The suggested tracking approach incorporates the mission requirements and fuel consumption, which can reduce fuel consumption and significantly lengthen the time of the satellite detection mission while maintaining the mission demands. This is in contrast to the current tracking technique.