电驱桥驱动的纯电动商用车悬架优化设计开题报告

1. 研究目的与意义（文献综述）

1.1 the purpose and meaning

since the reform and opening up, china's economy has been developing at a high speed.in 2019, the production and sales of automobiles were 25.721 million and 25.769 million, respectively, down 7.5% and 8.2% year on year, respectively.the sales volume of commercial vehicles in december was 445,000, up 3.9% year on year.in 2019, the total sales volume was 4.324 million, down 1.1% year on year.although the automobile and passenger vehicles suffered a waterloo, but the overall performance of the commercial vehicle market is good, still maintain the upward trend.with the development of battery technology in china, electric vehicles have gradually entered people's lives. from the perspective of national policies and environmental protection, electric vehicles will occupy an important position in the automotive industry in the future.

suspension system is an important structure in automobile. the evaluation index of suspension performance is closely related to the kc characteristic of the suspension. the kinematic characteristic of the suspension is called k characteristic, and the elastic dynamic characteristic of the suspension is called c characteristic [1].at present, the research on the characteristics of suspension in china mainly focuses on the performance change of damping element and elastic element under the excitation of different road surfaces, thus changing the characteristics of suspension and affecting the ride comfort.studies at home and abroad generally focus on the optimization of the suspension structure, but rarely directly study the suspension characteristics [2].although the majority of electric vehicle development is now based on the traditional fuel vehicle chassis, the use of the original vehicle suspension system, that is, the centralized drive of electric vehicles.however, another form of distributed drive electric vehicle is different from it. the hub motor is introduced, which increases the unsprung mass and the inertia of wheel rotating parts, affecting the smoothness of the vehicle.at the same time, because there is an extra motor on the original basis, the sprung mass is greatly improved, thus tire dynamic load is increased, vehicle grip performance is reduced, and thus vehicle handling stability becomes worse.different roads have different incentives for cars. the roads driven by cars can be mainly divided into two categories. one is the random road surface.the other is the pulsed pavement, which has some obstacles, including bumps and pits.the convex block has rock, well cover, buffer zone, etc.these surfaces can suddenly increase the excitation several times, affecting smoothness and handling stability, making passengers uncomfortable and even causing dangerous accidents [3].

2. 研究的基本内容与方案

2.1 thebasic contents and objective of the research

aiming at a pure electric commercial vehicle driven by electric drive bridge, the smoothness of the whole vehicle was analyzed, and the suspension was optimized.the main contents of the paper are as follows:

1. establish the all-electric commercial vehicle model based on electric drive bridge and leaf spring suspension.

3. 研究计划与安排

4. 参考文献（12篇以上）

[1]sheng liangliang. k of heavy card front suspension based on virtual prototype technology;research and optimization of c characteristics [d]. hefei university of technology,2019.

[2]shi bing. a suv suspension kbasic research on the influence of c characteristics on vehicle smoothness [d]. jilin university,2015..

[3]lai qi. vehicle smoothness analysis under typical road impact condition [d]. jilin university,2018.