On the basis of kinematic analysis and kinetic analysis,this paper points out the vibration causations of the tripod universal joint.

On the basis of kinematic analysis of the tripod universal joint, this paper analyses the motion errors of this system, which related to the manufacturing error, installation error, bearing clearance, and so on.

The motion error of the tripod universal joint is analyzed on the basis of kinematic analysis.

Dynamic force analysis of fork rod of the aerial working platform in substation;

Study on the Dynamic Properties of Cross-legged Parallel Machine Tool;

Geometrical error models of a parallel kinematics machine tool(PKM) on the basis of structural character of cross-legged are built by the differential vector method.

The code of the responsible unit to assemble the crossing bar is recorded through adding the seal lock, so as to have the inspection and repair unit pay atten- tion to the inspection and repair quality of the cross- ing bars.

The dynamic force of the crossing bar of the K6 Bogie used in the 20,000 ton heavy-duty train in Da-Qin Railroad is identified in two methods:the material mechanic method and the quasi-static method.

By the computer simulation and numerical calculation, not only have the free vibrating modals of the crossing bar been obtained, but also the dynamic characteristics of the crossing bar have been recognized while the car negotiates on curves and runs on straight railway with stochastic excitation.