As the matrix of heavy-duty truck, automobile frame is supporting all the relevant mechanics of sprung mass such as the engine, clutch, transmission, steering, driver's cab, and cargo box etc.

The control gains which are tuned according to road frequency are used to the velocity feedback of the sprung mass and the unsprung mass.

The calculation method of CG of locomotive is depicted. Then it is introduced how to determine and obtain secondary sprung CG, bogie mass CG and actual locomotive CG by four pivot point method.