The dynamics analysis of crank and connecting rod mechanism of a passenger-car engine is carried out by using the large size engineer software.At first

the rigid body dynamics model of TU5JP4 engine crank and connecting rod mechanism is built based on ADAMS/Engine module.Then

the crank and connecting rod mechanism is regarded as flexible body.By using Pro/E software

the solid model is built and the modal neutral document is produced by ANSYS/Flex modular.At last

the above-mentioned imitate state neutral document is ducted into ADAMS software.The system of rigid-flexible mixed dynamics model is constituted and the related numerical simulation research is carried out.A method for the design and improvement of crank and connecting rod mechanism of passenger-car engine is provided.