问扭转振动是什么呢?

abstract     automotive powertrain vibration include torsional vibration and vehicle vibration, the vibration directly affect car performance, fuel economy, handling stability, ride comfort and driving safety, especially with the lightweight vehicle structures and the continuous people on the vehicle to improve ride comfort requirements, making more and more problems for vehicle vibration, vehicle vibration, as one of the main excitation source of motivation to become the engine vehicle vibration study of focus; recent computer technology with the rapid development of computer simulation based on virtual prototyping and finite element analysis methods are widely used in more and more of the product development and designs to solve the case of vehicle vibration design zhong to the problem. however, the engine performance and driving forces on the calculation of car but rarely in the study. through the establishment of the thermodynamic model of the engine and engine mechanical model of motivation, the use of matlab software, a variety of exciting force vehicle vibration calculation and analysis for automotive powertrain torsional vibration and vehicle vibration study and improvement to provide accurate data.

最可以理解的机械表中的那个摆。（一圈一圈的那个）