MECA0525-1

Duration

30h Th, 15h Pr, 4h Labo., 8h Proj., 1d FW

Number of credits

	Master in mechanical engineering (120 ECTS)	5 crédits

Lecturer

Pierre Duysinx

Language(s) of instruction

English language

Organisation and examination

Teaching in the second semester

Schedule

Schedule online

Units courses prerequisite and corequisite

Prerequisite or corequisite units are presented within each program

Learning unit contents

The characteristics of ground vehicles may be described in terms of its performances, handling, and ride. Performance charactristics refer to its ability to accelerate, decelerrate, to develop drawbar pull, and to overcome obstacles. Handling quantities are concerned with the response of the vehicle to drivers' command and its ability to stabilize its motion against external disturbancies. Ride characteristics are related to the vibration of the vehicle excited by the surface irregularities and its effects on passengers and goods.
The lecture is mainly focussed on road vehicles, but introduction is also given to railway vehicles.
The following points will be adressed:

Power source characteritics (Internal combustion engines, electric motors) transmissions and drivetrains,
Road resistance forces: rolling resistance, aerodynamic forces, slope forces,
Description and modelling of tire-ground and wheel-rail forces,
Description and calculation of performance criteria (maximum speed, acceleration, elasticity, etc.),
Fuel consumption and emissions measures, driving cycles, experimental testings,
Braking performance,
Tire mechanics,
Steering geometry (Ackerman theory)
Steady state handling of a two-axle vehicle: bicycle model, under/oversteer gradient,
Transient reponse of a two-axle vehicle
Roll-over,
Human response to vibrations,
Road vibration isolation: quater car model, sensitivity to sprung and unsprung masses, suspension damping and stiffness,
Pitch and bounce modelling: two-dof-model,
Introduction to crash mechanics and accident mechanics

Learning outcomes of the learning unit

To master the fundamental concepts of vehicles when evaluating their characteristics (performance, handling, ride) and their relationships with the design variables under various operating conditions.
To be able to understand the theoretical concepts and to apply them in numerical exercices.
To be able to write a computer code to calculate the performance and the dynamic behaviour of a raod vehicle at the preliminary design stage.

Prerequisite knowledge and skills

Knowledge in Theoretical Mechanics, Machine Design and Construction, Vibration of Mechanical Systems, Control Systems, Applied Thermodynamics.

Planned learning activities and teaching methods

Closed-form exercices, computer exercices (MATLAB), laboratory (chassis dynamometer).

Mode of delivery (face-to-face ; distance-learning)

The lectures are given on Thursday morning at the second quadrimester (from beginning of February to end of May). 13 lectures (4 hours) + one laboratorie. Exam in June.

Assessment methods and criteria

Oral exam (theory: 40 %)
Wirtten examen (exercices: 30%)
Laboratory reports (10%)
Computer work (20%)

Work placement(s)

Organizational remarks

None

Contacts

Pierre Duysinx, LTAS - Automotive Engineering Institute of Mechanics and Civil Engineering, Building B52 Allée de la Découverte 13A, 4000 Liège Téléphone : +32 4 366 9194, Fax : +32 4 366 9159, Email : P.Duysinx@uliege.be

Performance and dynamics of vehicles