Dynamic Analysis of a Wire-Driven Parallel Manipulator for Low-Speed Wind Tunnels

现代飞行器对低速风洞试验的攻角范围要求很大,往往无法用传统支撑系统来实现.文中提出1个新型的绳牵引并联支撑系统,用来支撑缩小比例为1∶100的F-15E"攻击鹰"战斗机模型的低速风洞试验,该支撑系统使缩比模型的3个姿态角能实现±90°的变化.通过做粗略风速为28.8 m.s-1的吹风实验,发现设计方案是可行的.对用于低速风洞大攻角支撑系统的绳牵引并联机构进行逆动力学分析,并建立机构的动力学模型求逆动力学解,仿真分析缩比模型进行纯平动和纯转动时各根绳的拉力值.由系统的动力学线性挠动方程求出机构系统的固有频率,通过仿真分析求出缩比模型单独绕某一坐标轴转动时,其在特定位姿处的最小固有频率.The range of the incidence of modern vehicles in low speed wind tunnel tests is usually very large which can′t be carried out by a traditional frame support system.A new wire-driven parallel manipulator for low-speed wind tunnels to suspend a 1∶100 scale model of F-15E is presented.By this design,the ranges of pitch,roll and yaw angles of the scale model at the home pose are all-90～90 °.Such a design has been validated by wind tunnel tests in a wind speed of 28.8 m·s-1.And it has been found that there is only very little vibration occurring at the end of the scale model which is less than that in a traditional frame support system.This paper focuses on the dynamic analysis of this wire-driven parallel manipulator,and the solutions to the inverse dynamics problem are obtained,two case studies are given to obtain the tension of each wire when the scale model translates and rotates,the simulation results of which will provide some data for the further structural design of the system.Also the dynamic characteristics of the manipulator are analyzed and the natural frequencies at the given configuration are computed according to the linear perturbation dynamic equation,and three case studies are given to compute the minimal natural frequencies of a certain configuration when the scale model rotates about an axis,the simulation results of which will provide the criteria for analysis of the rigidity and vibration characteristics of the manipulator.国家自然科学基金资助项目(50475099);; 国务院侨办基金资助项目(05Q0019);; 华侨大学高层次人才科研启动基金(06BS218);; 福建省青年人才创新基金(2006F3083