Automobile Theory

Beijing University of Chemical Technology

Syllabus for Automobile Theory

Ⅰ. General Information

Ⅱ.Curriculum Nature and Course Objectives

2.1 Curriculum Nature

<Automobile Theory> is one of the core courses of vehicle engineering specialty and an elective course for mechanical specialty.

2.2 Course Objectives

Through the study of this course, students can find out the influence law of vehicle structural parameters and service parameters on vehicle driving performance on the basis of mastering vehicle driving performance indicators and evaluation methods, so as to improve vehicle driving performance,; Combined with the typical case analysis and project research of automobile development, cultivate students' innovative design ability, engineering practice ability and teamwork ability, so as to stimulate students' feelings of home and country and responsibility, so as to lay a solid foundation for their further study and engaging in automobile design, research, manufacturing and management in the future.

The specific course objectives are as follows:

G1: learn how to evaluate the driving performance of vehicles, and be able to use the simplest (easy to calculate and test) indicators to reflect the driving performance of each vehicle (power, fuel economy, braking, handling stability, ride comfort, traffic ability, etc.);

G2: learn to use the most basic method and the most effective calculation or test method to obtain the evaluation index of vehicle performance;

G3: be able to analyze the influence of vehicle structural parameters on vehicle performance, that is, be able to analyze how to improve vehicle design by means of calculation or test.

Ⅲ. The Corresponding Relationship between Course Objectives and Graduation Requirements

Table 1 Correspondence between course objectives and graduation requirements

Ⅳ. Teaching Contents and Requirements for the Lecturing Part

4.1 Vehicle power performance (6 class hours)

4.1.1 Teaching objectives (G1, G2, G3)

Master all kinds of resistance of automobile driving; Master vehicle power performance index and evaluation method; Master the driving attachment conditions of the vehicle and the power balance of the vehicle; Understand the power performance of vehicles equipped with hydraulic torque converter; Master the power calculation of new energy vehicles; Understand the vehicle power experiment.

4.1.2 Teaching content

(1) Vehicle power performance index;

(2) Driving force and driving resistance of the vehicle;

(3) Driving force driving resistance balance diagram and dynamic characteristic diagram of vehicle;

(4) The adhesion condition and adhesion rate of the vehicle;

(5) Power balance of vehicle;

(6) Power performance of vehicles equipped with hydraulic torque converter;

(7) Power performance of new energy vehicles.

4.1.3 Teaching requirements

(1) Understand: basic concepts such as automobile power evaluation index, automobile driving force and driving resistance, automobile driving equation, automobile adhesion and adhesion conditions, automobile power characteristic diagram, power factor, automobile power balance, etc.

(2) Comprehend: longitudinal force analysis, vehicle driving equation series formula, dynamic characteristic diagram, power balance diagram, analysis of influencing factors of vehicle dynamic performance.

(3) Master: Calculation and analysis of vehicle power performance (including maximum vehicle speed, maximum climbing gradient and acceleration time).

4.2 Fuel economy of automobile (3 class hours)

4.2.1 Teaching objectives (G1, G2, G3)

Master the evaluation index of automobile fuel economy, the calculation of fuel economy and the factors affecting automobile fuel economy.

4.2.2 Teaching content

(1) Evaluation index of automobile fuel economy;

(2) Calculation of automobile fuel economy;

(3) Factors affecting the fuel economy of automobile;

(4) Fuel economy calculation of vehicles equipped with hydraulic torque converter;

(5) Economy of new energy vehicles;

(6) Automobile power performance and fuel economy test.

4.2.3 Teaching requirements

(1) Understand: the concept of automobile economy and its evaluation index.

(2) Comprehend: the basic formula of fuel economy calculation and the factors affecting vehicle fuel economy.

(3) Master: Calculation of fuel economy under cycle conditions.

4.3 Selection of vehicle power plant parameters (2 class hours)

4.3.1 Teaching objectives (G1, G2, G3)

Master the selection of engine power, minimum transmission ratio, maximum transmission ratio, number of transmission gears and transmission ratio of each gear; Understand how to use fuel economy acceleration time curve to determine power plant parameters.

    4.3.2 Teaching content

(1) Selection of engine power;

(2) Selection of minimum transmission ratio;

(3) Selection of maximum transmission ratio;

(4) Selection of the number of gears of the transmission system and the transmission ratio of each gear;

(5) The parameters of the power plant are determined by using the fuel economy acceleration time curve.

4.3.3 Teaching requirements

(1) Understand: the basic concept of automotive power train parameters.

(2) Comprehend: the principle of selecting automobile power train parameters and the significance of matching.

(3) Master: the method of selecting automobile power train parameters.

4.4 Vehicle braking performance (6 class hours)

4.4.1 Teaching objectives (G1, G2, G3)

Master the evaluation index of braking performance and the force of wheels during braking; Understand the braking efficiency and constancy of the vehicle; Master the directional stability of the vehicle during braking; Master the proportional relationship between the braking force of front and rear brakes, and understand the ABS system and characteristics and automobile braking experiment.

4.4.2 Teaching content

(1) Evaluation index of braking performance;

(2) Stress of wheel during braking;

(3) Braking efficiency and its constancy;

(4) Vehicle directional stability during braking;

(5) Proportional relationship between braking force of front and rear brakes;

(6) Test of vehicle braking performance.

4.4.3 Teaching requirements

(1) Understand: the concept of braking force, braking force, braking coefficient and its evaluation of the braking force, and the concept of the braking force, the braking force and the slip coefficient of the vehicle.

(2) Comprehend: analysis of the relationship between wheel force, ground braking force / brake braking force / adhesion during braking, analysis of braking process, analysis of braking direction stability, and analysis of the proportional relationship between the braking force of front and rear brakes.

(3) Master: analysis of braking process, calculation of braking distance and braking deceleration, and analysis of factors affecting braking performance.

4.5 Vehicle handling and stability (6 class hours)

4.5.1 Teaching objectives (G1, G2, G3)

Master the evaluation indexes of vehicle handling and stability and tire cornering characteristics; Master the steady-state response of linear two degree of freedom vehicle model and understand the transient response; Understand the relationship between vehicle handling and stability and suspension and steering; Road experiment to understand the handling and stability of vehicles.

4.5.2 Teaching content

(1) Overview;

(2) Sideslip characteristics of tires;

(3) Response of linear 2-DOF vehicle model to front wheel angle input;

(4) The relationship between vehicle handling stability and suspension, steering system and transmission system;

(5) Electronic control system to improve handling stability;

(6) Car rollover;

(7) Road test of vehicle handling and stability.

4.5.3 Teaching requirements

(1) Understand: vehicle coordinate system, tire coordinate system, tire sideslip angle, sideslip stiffness, vehicle time domain response, steady-state steering characteristics, steering sensitivity, stability factor and other basic concepts.

(2) Comprehend: tire cornering characteristics, differential equations of motion of linear two degree of freedom vehicle model, parameters characterizing steady-state response.

(3) Master: steady state response and transient response of linear 2-DOF vehicle model to step input of front wheel angle.

4.6 Vehicle ride comfort (5 class hours)

4.6.1 Teaching objectives (G1, G2, G3)

Master the evaluation index of vehicle ride comfort, the statistical characteristics of road surface and the simplified method of vehicle vibration system; Vibration of single mass system; Familiar with the vibration of double mass system of body and wheel and double axle vehicle; Familiar with automobile ride test.

4.6.2 Teaching content

(1) Evaluation of response and smoothness of human body to vibration;

(2) Statistical characteristics of pavement roughness;

(3) Simplification of vehicle vibration system;

(4) Vibration of single mass system;

(5) Vibration of double mass system of vehicle body and wheel and vibration of double axle vehicle;

(6) Vibration of human body seat system;

(7) Vehicle ride test and data processing.

4.6.3 Teaching requirements

(1) Understand: the response of human body to vibration, the evaluation index of vehicle ride comfort, the statistical characteristics of road roughness - the concept of power density.

(2) Comprehend: simplification of vehicle vibration system

(3) Master: vibration analysis of single mass system and double mass system.

4.7 Vehicle trafficability (4 class hours)

4.7.1 Teaching objectives (G1, G2, G3)

Master the concept of vehicle trafficability; Understand the physical properties of soft ground and the formation of vehicle hook traction; Master the geometric parameters of clearance failure and traffic ability.

4.7.2 Teaching content

(1) Vehicle trafficability evaluation index and geometric parameters;

(2) Physical properties of soft ground;

(3) Vehicle hook traction;

(4) Traction trafficability calculation;

(5) Obstacle conditions of clearance failure;

(6) The ability of cars to cross steps and trenches;

(7) Vehicle passing test.

4.7.3 Teaching requirements

(1) Understand: the evaluation index and geometric parameters of vehicle trafficability, and the basic physical properties of soft ground.

(2) Comprehend: Vehicle trafficability model.

(3) Master: the obstacle conditions of jacking failure, the obstacle conditions of contact failure, and the analysis of the ability of the car to cross steps and trenches.

Ⅴ.Teaching Contents and Requirements for the Practical Part

This course focuses on theoretical study. Due to the limited class hours, automobile theory and practice teaching is carried out in production practice.

Ⅵ. Evaluation Standards

6.1 Assessment methods and contents

The teaching links of this course include classroom teaching, extracurricular reading, in class discussion and homework. The assessment methods include process assessment and result assessment. The process assessment is the comprehensive assessment of classroom participation (including attendance and classroom performance) and exercise homework. The final examination is a closed book written examination based on the contents of classroom teaching, extracurricular reading and in class discussion. The examination questions include blank filling, selection, calculation and comprehensive application. The specific content is shown in Table 2.

Table 2  Course assessment and its supporting relationship to course objective

The final assessment of the course is a comprehensive assessment of the process assessment and final examination, and the achievement of the course objectives is evaluated on this basis, as shown in Table 3.

Table 3 Course assessment methods and contents and their supporting relationship

to course objectives

6.2 Scoring Criteria

The scoring standards of classroom performance (including attendance, quiz and participation) and exercise assignment are shown in table 3-table 4. The final examination is scored according to the scoring standard of the final examination paper of the current time according to the percentage system. The total score consists of three parts: class performance score accounts for 25%, exercise homework score accounts for 25%, and final score accounts for 50%.

Table 4 Scoring criteria for classroom performance

Table 5 Scoring criteria for exercise assignments

Ⅶ.Textbooks and Recommended References

7.1 Textbook

[1] Yu Zhisheng. Automobile Theory (6th Edition). Beijing: China Machine Press, 2018 (Ministry of education curriculum materials for the 21st century, national planning materials).

7.2 Reference books

[1] Min Haitao, Wang Jianhua. Automobile Design (5th Edition). Beijing: China Machine Press, 2021 (the 13th five year plan for the publication of national key publications, a series of excellent textbooks for Modern Mechanical Engineering).

[2] Yu fan, Lin Yi. Automotive System Dynamics (2nd Edition). Beijing: Machinery Industry Press, 2017 (national planning textbook, 13th five year plan automobile planning textbook).

Written by YAO Mingtao