亚洲一区欧美在线,日韩欧美视频免费观看,色戒的三场床戏分别是在几段,欧美日韩国产在线人成

In order to research the influence of friction on the operation of the parallel mechanism, the dynamic analysis of the 3-PRS parallel mechanism based on joint friction was carried out. Firstly, the ideal terminal motion trajectory of the 3-PRS parallel mechanism was planned, and the mechanism had three degrees of freedom (DOFs), including two rotation DOFs and one movement DOFs. The vector motion was used to analyze the kinematics of the mechanism, and the velocity and acceleration of each component were analyzed. Secondly, three joint friction models, including Coulomb friction model, Coulomb-viscous friction model and Coulomb-viscous-static friction model were proposed. Under the condition of applying friction between joints, the dynamic modeling of the components and the overall structure of the 3-PRS parallel mechanism was established based on the Newton-Euler method. Finally, the influence of load on the friction of each joint was analyzed. The specified ideal motion trajectory was applied to the terminal of the mechanism. According to the inverse dynamics, the influence of joint friction on the slider driving force was analyzed and the maximum errors of the three slider driving forces were 1.40%, 1.51% and 1.49%, respectively. The three slider driving forces from the inverse dynamics were taken as the main driving forces of the 3-PRS parallel mechanism, and the influence on the terminal motion trajectory caused by the different friction models between joints was analyzed through forward dynamics. The research results showed that the terminal motion trajectory of the 3-PRS parallel mechanism had great impact under different joint friction models.