A Dynamic Micro-Thrust Reconstruction Algorithm Independent of Parametric Models

Micro-thrusters play a pivotal role in achieving drag-free control in space-based gravitational wave detection missions. Dynamic micro-thrust reconstruction is crucial for comprehensive evaluation and understanding of the operational process of micro-thrusters and for the advancement of higher performance micro-thrusters. The conventional dynamic thrust reconstruction method, inversion of dynamic equation (IODE), heavily relies on the dynamic equation model. This dependence leads to performance decline when discrepancies emerge between the model and the actual system, coupled with a time-consuming parameter estimation process. To overcome these limitations, this article introduces an innovative algorithm breaking free from the constraints of parametric models, named the dynamic matrix control algorithm-based dynamic thrust reconstruction (DMC-DTR) algorithm. In this article, the underlying principles and algorithm process of DMC-DTR are presented. Comparative analyses of DMC-DTR and IODE are conducted through both simulated and real dynamic thrust measurement experiments. The results indicate that DMC-DTR closely matches the performance of IODE when the dynamic equation model aligns with the actual system. Notably, when the model diverges from reality, DMC-DTR outperforms IODE significantly, showing the enhanced universality of the proposed algorithm. In addition, the simulation reveals that DMC-DTR exhibits better performance than IODE at lower sampling frequencies. Moreover, the dynamic thrust from a cold gas micro-thruster is reconstructed by DMC-DTR to demonstrate its practical application.