1. 研究目的与意义（文献综述）

with the rapid development of china's economy and the improvement of machinery manufacturing, the number of cars in many cities growing rapidly. the issues of urban traffic congestion and air pollution have been seen since several years. in order to reduce the growing of urban traffic and environment issues, public transportation will become the effective method to solve the problem. however, the traditional fuel buses have environment pollution and poor fuel economy disadvantages. they cannot address this issues effectively. fuel cell electric buses can overcome these deficiencies. majority of fuel cell electric buses are powered by hydrogen fuel cell that generates water as the final reactant. there are no any other pollutants. and the energy conversion efficiency is more than 60 percent. in addition, fuel cell electric buses have a longer range than ordinary new energy buses. fuel cell electric buses can inject hydrogen fuel in a short time and driving smoothly.

automobile brake system play a vital role in the vehicle's safety aspect. with the progress of auto technology and the improvement of driving speed, the importance become more obvious. there are many kinds of auto brake system. the working principle of the automobile brake system are all the same. in order to achieve the purpose of vehicle deceleration, the braking system converts kinetic energy into heat energy. the form of the braking system has taken place great changes because of the development of clean energy vehicles. fuel cell electric vehicles use a hybrid braking system. when the braking system working, the motor will become a generator. it transform kinetic energy into electric energy and store in the battery. when the load power is bigger than the rated power of the fuel cell system, the vehicle enable hybrid traction mode, battery and fuel cell will supply power together.

2. 研究的基本内容与方案

1、Understand the situation at home and abroad and research significance

2、Understanding fuel cell electric bus braking system's main structure and working principle

3、Calculation the distribution of braking force and select the type of braking drum

4、According to the parameters calculate the machine body stability of braking system, and design the process of manufacture.

5、According to the design size finish body parts drawing

6、According to the design size finish assembly drawing

7、Study the 3D drawing software CATIA and build 3D model

8、study the simulation software ANSYS and finish finite element analysis

In term of the design of the fuel cell bus braking system, determining the brake structure selection and scheme analysis at first. Then calculating the main parameters and the intensity of the braking system. Thirdly Checking brake shoe lining pressure distribution rule and the radial deformation of the gauge. Finally finishing fuel cell bus braking system parts drawing assembly drawing.

1.Refer to relevant literature, and translate foreign language reference Understand the fuel cell bus structure and working principle of the braking system

2.Data acquisition and analysis argument and choice on the braking system solution

3.Draw pattern according to the result of calculation and finishing 3D model

4.Write and complete design specification of braking system

3. 研究计划与安排

7th semester 19-20th weeks determine the design plan descriptions of the graduation design topic selection and finish the information collection

8th semester 1st week complete the opening report and document retrieval

8th semester 2-3rd weeks complete data collection and finish internship report

8th semester 4th week translate foreign language

4. 参考文献（12篇以上）

[1] andrew j. day. braking of road vehicles[m]. london. heinemann educational books. 2014. 35-65.

[2] cikanek s r, bailey k e. regenerative braking system for a hybrid electric vehicle[c]. american control conference. ieee, 2002:3129-3134.

[4] chen j j, zhou l x, ning x b, et al. design of hybrid electric bus on regenerative braking system[j]. applied mechanics amp; materials, 2013, 300-301:333-337.