六自由度Stewart平台参数化建模及优化

Parametric Modeling and Optimization of Six-DOF Stewart Platform

飞行模拟器是一种训练飞行员的地面模拟设备,能够逼真地再现真实环境中飞机的飞行状态,具有精度高、承载能力大、安全可靠、使用灵活等优点。飞行模拟器通常采用六自由度Stewart平台,其运动特性是影响本身性能的关键指标。首先建立六自由度Stewart平台的参数化模型,设计其运动轨迹并进行试验研究,分析多种结构参数并确定平台的基本尺寸;其次根据基本尺寸建立完整的三维模型,并分析其空间运动状态;最后对其进行运动学、动力学仿真分析并研究整体的性能。六条支腿的伸缩量轨迹点和五次多项式拟合曲线基本重合,其伸缩运动符合五次多项式规律,保证了速度和加速度不发生较大的突变,从而确保了上运动平台的稳定性。

Flight simulator is a ground simulator for training pilots.It can vividly reproduce the flight status of aircraft in real environment.It has the advantages of high accuracy,large carrying capacity,safety and reliability,and flexiblility.Flight simulator usually uses Six-DOF(six degree of freedom,Six-DOF)Stewart platform,and its motion characteristics are the key indicators affecting its performance.Firstly,the parameterized model of the Six-DOF Stewart platform is established,its trajectory is designed and tested,and various structural parameters are analyzed and the basic dimensions of the platform are determined;secondly,a complete three-dimensional model is established according to the structural parameters,and its spatial motion state is analyzed;finally,the kinematics and dynamics simulation analysis is carried out and the overall performance is studied.The trajectory points of the six legs are basically coincident with the fitting curve of the quintic polynomial,and the movement of the six legs is in accordance with the quintic polynomial law,which ensures that the speed and acceleration do not have large mutations,thus ensuring the stability of the upper moving platform.