柔索驱动式航天员虚拟微重力训练系统控制与实验

针对现有的航天员地面微重力训练设备存在成本高、单次训练时间短、模拟精度低等问题，提出了一种柔索驱动的航天员虚拟微重力训练系统。通过采样航天员对作业对象的操作力，控制柔索驱动虚拟物体(末端执行器)运动，使虚拟物体符合在微重力环境中的运动规律。建立了柔索驱动训练系统的动力学模型，分析了系统的特性。针对传统力伺服系统多余力对控制力精度影响较大且难以克服的问题，提出了一种使用弹簧产生柔索张力的并联柔索全位置型控制方法,并引入力/速局部反馈的控制策略。实验结果表明，系统克服多余力效果明显，可以获得较高的驱动力控制精度；虚拟质量在操作力作用下的运动符合在微重力环境中的运动规律，且有较高的模拟精度；系统稳定性良好，可以实现微重力环境中移动不同质量物体的虚拟作业训练。

Control and Experiment of Flexible cable driven Virtual Microgravity Training System for Astronauts

In view of the problems of high cost, short training time and low simulation accuracy of the existing ground microgravity training equipment for astronauts, a virtual microgravity training system driven by flexible cables is proposed. By sampling the astronaut’s operating force on the object, the cable is controlled to drive the virtual object (end effector) to move, so that the virtual object conforms to the motion law in the microgravity environment. The dynamics model of the cable driven training system is established and the characteristics of the system are analyzed. Aiming at the problem that the excess force of the traditional force servo system has great influence on the control accuracy and is difficult to overcome, a control strategy of all position control of parallel cables using springs to generate cable tension and introducing local force/velocity feedback is proposed. The results of experiments show that the system can overcome the excess force obviously and obtain higher driving force control accuracy. The motion of virtual mass under the action of operating force is consistent with the motion law in the microgravity environment, and has high simulation accuracy. The system has good stability and can realize virtual training of moving different mass objects in the microgravity environment.