在轨加注任务中变质量特性下的空间操作臂状态扩展自适应镇定控制

State expansion adaptive stabilization control of space manipulator with variable mass characteristics under on-orbit refuelling task

模块更换方式在轨加注任务面向不同类型的多个待加注目标与推进剂模块,过程中涉及航天器对接与分离、推进剂模块拆卸与组装等多种操作,研发时需要考虑系统中质量特性变化复杂,以及地面验证中存在的全周期、遍历性的任务级微重力模拟试验难以实现的问题。首先,针对地面调试良好时在轨加注空间操作臂系统可能被掩盖的非线性动力学特性,分析了一定参数范围下,任务执行过程中负载和基座质量特性变化对空间操作臂动力学特性和控制性能的影响。随后为实现对控制对象及环境改变的自适应性,基于惯性矩阵分解与重力载荷矩阵线性化,设计g的自适应律,并扩展系统状态变量,建立系统的Hamilton模型,进而基于能量函数整形与阻尼注入的无源性控制思想,设计预置镇定控制律,提出一种可对不同工况下的系统非线性实现自适应镇定的控制方案。最后,通过仿真研究验证了所提控制方案的有效性。

On-orbit refuelling based on module replacement involves various operations such as docking and separation of spacecraft and disassembly and assembly of propellant modules,and are oriented towards many different types of spacecrafts and many sizes of propellant modules.The development phase needs to consider the complex changes in mass characteristics,and the fact that the whole cycle,ergodic task-level micro-gravity simulation test in ground validation is difficult to achieve.Considering these problems,this paper firstly analyzes the influence of changes in load and base mass characteristics on the dynamic characteristics and control performance of the system.Then,to realize the adaptability to the changing control objects and environment in the process of operation task,the adaptive law of gravity acceleration g is designed based on inertia matrix decomposition and gravity load matrix linearization,and the system state variables are extended to establish the Hamiltonian model of the system.Furthermore,based on the idea of passive control of energy function shaping and damping injection,the control law of presetting stabilization is designed,and a control scheme of adaptive stabilization of system nonlinearity under different working conditions is proposed.The simulation results verify the effectiveness of the proposed control scheme.