Vehicle Dynamics I: Accelerating and Braking

By Univ.-Prof. Dr.-Ing. Martin Meywerk - Professor for Automotive Engineering at the Helmut-Schmidt-University in Hamburg

https://iversity.org/c/30?r=6bd45

From Bugatti Veyron to Volkswagen Beetle, from racing to passenger car: Learn here how they speed-up and slow-down! 

About this course

The mobility has influenced many areas of a human's life since the invention of the wheel. While, in the early days of motorized vehicles, technical developments concentrated on simple mechanical or electrical issues , in the past decades, the electronics and with it, the microprocessor technology have become a central part of innovation in vehicles. Future developments of trendsetting style will be the conversion of the drive train from purely internal combustion engine to hybrid or alternative powertrain systems, the car-to-car communication and the autonomous vehicles. Challenges that make these technical developments partly necessary, come from a desirable reduction in CO2 emissions and an increase in the active safety. To understand the recent developments, especially in the field of alternative propulsion strategies and also in the area of autonomous or semi-autonomous vehicles, knowledge of the basic driving physics is essential, as these innovations can be understood solely as the underlying laws of physics are known.

For this reason three parts of the vehicle dynamics, the longitudinal, the lateral and the vertical dynamics are important.

Acceleration and Braking

In this first part longitudinal dynamic aspects of vehicles will be illuminated.
Clear and brief: acceleration and braking
In Detail: After an introduction we will look at driving resistances and slip, we will explain the demand of power and limits of a car, then we will clarify the needs for clutch and gear and we will look at the rear and front weights during acceleration and braking. The course will be finished by two applications from automotive mechatronics.

Course Structure

1. Introduction
2. Driving Resistance
3. Slip
4. Power Demand, Limits
5. Clutch, Gearbox
6. Front/Rear Weights
7. Application: Anti-Lock Braking System
8. Application: Recovery of energy

Learning Outcomes

• You will understand basic principles of accelerating and braking a car
• You will know the driving resistances and their influences to vehicle dynamics
• You understand the discrepancy between demands and limits of powertrain
• You understand the necessity of gears and clutch
• You understand the correlation between braking, wheel load and recovery of energy
• You are able to calculate simple properties of a car

Workload

Per week: 135 - 260 min.

• one video divided in 5 to 7 portions: 45 min.
• 5 – 7 question-clusters for knowledge: 20 -30 min.
• 2 – 3 question-clusters for comprehension: 25 – 50 min.
• Guided calculation for application
• P2P-problems to train analysis and synthesis skills: 45 min.
• wrap-up: 0 – 90 min. (depends on your previous knowledge and your comprehension) Preparation of the exam: 30 h

Course Format

The course uses a mixture of Screencasts (with handwritten derivations, drawings, formulas), Powerpoint slides and videos from real cars, simulated cars and testrigs.

Assessments

To assess the different levels of learning this course will use different form of assessments:

• Knowledge: Multiple choice,
• Comprehension: correlation between statements and parts of diagrams, formulas or driving maneuver (visualized by short simulation videos);
• Application: short guided calculations (open office),
• Analysis: P2P-problems: longer calculations or drawings

Prior Knowledge

You should have been successful in university courses in basic mathematics and in basic engineering mechanics, especially you need:

• Algebra
• Trigonometric Functions
• Differential calculus
• Linear Algebra: Vectors, Coordinate systems etc.
• Force, Torque, Equilibrium
• Mass, Center of Gravity, Moment of Inertia
• Method of Sections, Friction, Newton's Law
• (Lagrange's Equation)