【作者】 王捷冰；

【导师】 包钢；

【作者基本信息】 哈尔滨工业大学 ， 机械电子工程， 2010， 硕士

【摘要】 随着航天技术的不断发展,航天器将具有更高的姿态指向精度和跟踪控制能力,逐步向着智能化、敏捷化和多功能化的方向发展。先进技术的应用在确保航天器完成各种在轨服务的同时,也使航天器的发射和控制成为一种高风险高投入的任务,降低风险的一个有效途径就是对整个系统进行充分的地面试验验证。本文研究的五自由度气浮仿真试验系统能够在地面上复现太空中微重力、低摩擦的动力学环境,模拟航天器的轨道和姿态运动,可以将航天器的软硬件引入控制回路,有效的完成地面仿真验证。本文首先介绍了五自由度气浮仿真试验台的结构,分别阐述了气浮台各个功能单元的组成和工作原理;在Pro/ENGINEER环境下建立了气浮台的精确模型,进行了虚拟质心调节,为实际调平衡工作提供了可靠的依据,同时对模型进行了质量分析,计算出姿态控制的关键参数——惯量矩阵。根据刚体运动学和动力学的相关知识,建立了基于冷气—飞轮控制的气浮台位置和姿态模型,并对气浮台所受干扰力矩进行了简要分析,为后续位姿控制系统的设计提供了理论依据。结合气浮台位姿动力学模型,推导出位置和姿态的控制方程,分析了控制特性;针对冷气推进和飞轮两种执行机构各自的特点,分别采用改进滑模变结构控制和PID控制进行了控制器的设计,并进行了仿真验证。在现有的基于冷气推进的五自由度气浮台上进行了控制算法的验证,证明了五自由度气浮台能够完成相应的位置和姿态运动。更多还原

【Abstract】 Along with the development of the aerospace technology, the spacecrafts are expected to have higher attitude pointing accuracy and greater trajectory ability, and are expected to be more intelligent and agile while also being multifunctional. The application of advanced technologies not only ensure that the on-orbit-servicing spacecraft can finish the tasks, but also make the launching and controlling of a spacecraft to be a high-cost, high-risk venture. An effective way of reducing risk is that every parts of the system must be verified in the ground-base test-beds. The five degrees-of-freedom air bearing spacecraft simulator can create a micro-gravity and low-friction dynamic environment and simulate the motion of orbit and attitude. It can access directly circuit by hardware and software accomplishing the verification testing on the ground.This paper introduced the structure of the 5-DOF air bearing spacecraft simulator and work principle and component of every units. The precise model of the air bearing simulator was established in the Pro/ENGINEER environment.Accomplish the virtual centroid adjustment which can provide the basis for the actual centroid adjustment. Analysis the quality attribute of the simulator and calculate the inertia matrix which is the key parameter of attitude control system. Derive the math model of position and attitude of the simulator in which the actuators are air propulsion device and reaction wheel using equations of rigid body kinematics and dynamics. Analysis the disturbing forces and torques.Derive the controlling equations of the simulator’s position and attitude on the base of the math model which describe the dynamics of position and attitude. Design different controllers for the two kinds of actuators respectively based on the different control strategies Sliding Mode Variable Structure Control and PID.Verify Sliding Mode Variable Structure Control strategy using the 5-DOF air bearing simulator based on air propulsion. The results show that the 5-DOF air bearing simulator can be controlled accurately and effectively.更多还原