全文总字数：11551字

1. 研究目的与意义（文献综述）

Ⅰ. Purpose and significance (including analysis of research status at home and abroad and literature review)The brake pedal feel is the subjective feeling of the driver and one of the important evaluation indicators of braking performance, which directly affects the braking safety and driving comfort of the vehicle. In the process of vehicle braking, on the one hand, the driver plays an active control role in the closed-loop system of the people and 0vehicle, and on the other hand, the driver must be able to accurately and timely receive feedback from the vehicle and make further adjustments. For the braking process, the brake feeling of the vehicle is fed back to the driver through the brake pedal, which is of great significance to the driver's subjective feeling and vehicle speed control, and directly affects the vehicle's active safety.In order to improve the driving comfortability and safety, and reduce long-term driving fatigue, it is necessary to study the role and changes of brake pedal feel during braking, determine the factors that affect pedal feel, and make targeted improvements. In addition, in traditional braking systems, a good brake pedal feel is a necessary condition for good vehicle performance and an important indicator of vehicle user satisfaction. Therefore, it is necessary to do a thorough study of the feel of the brake pedal. Nowadays, with the rapid development of Chinese economy, especially the state's investment in infrastructure construction has been increasing year by year, the public transportation system that meets the requirements of low-carbon environmental protection and energy saving is becoming more and more perfect. Taking electric minibuses as an example, it is of great significance to analyze the simulation of brake pedal feel.1.Overview of domestic developmentThe subjective and objective evaluation research on brake pedal feel started late in China. Various automobile companies have not formed a mature and mature subjective evaluation system and objective evaluation standard yet. Most of the subjective evaluation work of brake pedal feel depends on foreign automobile companies and scientific research institutes. In response to this situation, various domestic auto companies are making some research attempts to break through in order to try to establish their own databases and use the process of research and analysis to summarize and form their own subjective evaluation processes and specifications. At present, there are few literatures on the methods and applications of subjective evaluation in China. That is, in recent years, some researches on subjective evaluation have been carried out in the key laboratory of Jilin University in China. And some universities have carried out in-depth research and analysis on subjective evaluation and objective testing of brake pedal sensations, and summarized some processes and specifications. The National Automobile Quality Supervision and Inspection Center has also conducted research on subjective evaluation test methods for automobile braking performance. The performance of vehicle braking systems ranges from ten aspects such as braking effectiveness, braking thermal degradation, braking water degradation, linear braking stability, bending, road braking, brake maneuverability, brake nodding, brake noise, brake vibration, and brake pedal feel. And a 10-point scoring method was used to propose a subjective evaluation of the performance of the brake system with the Radar chart.2.Overview of foreign developmentIn terms of the subjective evaluation of brake pedal feel, foreign automobile companies have carried out related research in the 1970s, and have formed their own mature and mature subjective evaluation systems to ensure their stable and excellent vehicle chassis dynamics.An American well-known automobile evaluation and consulting company JD-POWER collects and organizes brake sensations of after-sales customers of various brands of cars every year and provides them to various OEMs for reference. These achievements have played a positive role in improving the performance of foreign auto products and the development of auto companies to varying degrees.Japan's Toyota Motor has carried out such research in the 1960s. At that time, it purchased all the sedan models in the world, established a subjective evaluation database of brake pedal feeling for more than 200 vehicles, and subsequently During the evaluation process, it created its own five-point scoring rules and formulated detailed evaluation items. In addition, the subjective evaluation of vehicle driving dynamics performance established by Professor Bernd Heisenying and Professor Hans Jurgen Brander, combined with engineering development experience，elaborated the performance of the vehicle chassis subjective evaluation method of flow from the subjective and objective performance influencing factors.Despite the lack of theoretical analysis, it is also a rare reference material for subjective evaluation practitioners in recent years.

2. 研究的基本内容与方案

Ⅱ. the basic content, goals, proposed technical solutions and measures of the research (design).

1. basic content and goals

this article takes electric minibuses as the research object, through theoretical analysis, simulation verification and other methods, simulating and analyzing the brake pedal feel. the main content of the paper is as follows:（1）introduce the background and significance of the research, consult relevant literature to understand the research status and research methods of brake pedal feel at home and abroad, and according to the brake pedal feel evaluation system that has been consulted, selecte an evaluation standard for brake pedal feel of electric minibuses;（2）take electric minibuses as the research object, calculate and determine the basic parameters of the brakes, brake master cylinder, brake cylinders,and brake line based on their vehicle parameters;（3）establish a vehicle braking system simulation model based on geometric and physical characteristics;

（4）perform pedal feel simulation analysis and optimization.

3. 研究计划与安排

Ⅲ. schedule

1-2（18th to 19th weeks of 7 semesters）determine graduation project topics, improve graduation design tasks (relevant parameters), and collect data inside and outside the school.

3（first week of semester 8）project idea,literature search, completion report.

4～5（second to third week of semester 8）foreign paper translation, data collection.

4. 参考文献（12篇以上）

Ⅳ．read no less than 25 references (including no less than 3 foreign references in the past five years)

[1] 史文库，姚为民. 汽车构造，第六版. 北京：人民交通出版社.

[2] 余志生. 汽车理论，第六版. 北京：机械工业出版社.

[3] 李果. 汽车转向制动系统协同控制理论与应用. 北京：国防工业出版社.