From four aspects: stratum,time,material and construction the factors influencing the strength of deep-mixing pile are discussed;at the same time corresponding methods are proposed to increase the pile strength and bearing capacity of single pile.

In addition,a superior approach for measuring vehicular velocity is contrived,which solves the difficulty in verifying the acc.

In order to enhance the accuracy and overcome the limitation of representing the vehicular velocity with non driving wheel speed signals, which is commonly used in researching on automotive dynamic control systems at present, the dynamic and kinematics models of running vehicles and wheels are established.

To improve the safety performance of the Mini Car,strong measures should be taken on the aspect of drive stability,body rigidity and avoiding collision.