Tshlei Dsitnugd My Oon Kinematics And Mdep Aocft Rigid Body

The rigid body system dynamic problem has an important engineering background.It is very difficult to build rigid body model and get a fixed solution for the existing offriction, impact and other non-smooth phenomena. It is still a hotspot and difficultyquestion in this field. The first procedure is to calculate when the contact of rigid bodieshappens and where the contact point is. How to build an effective model is the key pointfor the rigid body contact and impact question.This paper studies non-fixed point and non-coordinated impact kinematics problemof the rigid body, establishes a direct calculation method to find out the contact pointand contact time. This method is based on the contact point slope and some constraints.The complicated iteration process to find potential contact point can be avoided by thismethod. The effectiveness of the method is proved through the impact between ellipseand smooth ground.The phenomenon that the energy is increased caused by complex sliding mode orerror simplified model method should be solved. Contact-impact model is built based oncontinuous contact force method. In this model nonlinear damping spring model is usedon normal and non-smooth Coulomb friction model is used on tangential. The classicexample of oblique impact is a rigid body system consisted by a member bar andground. Dynamics simulations are done in the process of impact for this classic example.Study the movement variation and the corresponding sliding mode of this system ondifferent friction coefficients, different initial velocity and different initial configuration.With this model, the complex tangential sliding mode during the impact process isdemonstrated; the phenomenon that the energy is increased after impact is avoided.Finally, the contact-impact model which is based on continuous contact force is used toverify the conclusion about tangential sliding mode in other paper.