Research On The Interference Checking Of Stewart Platform On The Basis Of VRML

In the 60's of the last century, Stewart used 6 degrees of freedom motion platform as a flight simulator. Since then it was widely used in motion simulation,parallel machine tools and other aspects of industry, and has caused wide attention, Followed with its application, the study on the 6-DOF platform are also carried out more deeply. The structure and property of the Platform depend on the five major structure parameters. So when making the overall design of platform, we need to design the five structure parameters, and have an interference checking for it.After that the best results would be selected from them. As the 6-DOF motion platform is a complex equipment, we need a virtual simulation for its movement and control, that is it needs a virtual environment. In this paper, the study was carried out to solve the above problems.First the basis geometry knowledge of the graphics conversion and vector calculation were introduced. The kinematic analysis respectively on the 6-DOF motion platform and its upper and lower hinge were studied. The mathematical model was built and solved, and the related parameters were derived. It was a basis for further modeling.In this paper, a static model of platform was established with VRML, and the static assembly relationship from the SolidWorks was restored. First the local reference coordinate system was defined for each part model, the principle how the coordinate system to be established was detailed. And then a transformation level from the root coordinate system to the local coordinate system for each part of platform was created. At last the static assembly of the platform according to the transformation level was completed.On the basis of the above study, the VRML's Script node was used to achieve dynamic assembly and parametric modeling of the platform. That is, at the beginning of the VRML's running, the parametric model was built in the initialization function. In the whole process of the VRML's running, the dynamic model was established in real time in the event response functions. So if the regulation of platform motion was given, the motion simulation can be carried out.Finally, with the Collidee object, a method of interference checking between platform components was given, and the travel restrictions of piston rod were added to the event response functions. The predetermined target of the task was achieved.