Duration
30h Th, 15h Pr, 4h Labo., 8h Proj., 1d FW
Number of credits
| Master of Science (MSc) in Mechanical Engineering (EMSHIP+, Erasmus Mundus) | 5 crédits |
Lecturer
Language(s) of instruction
English language
Organisation and examination
Teaching in the second semester
Schedule
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 vehicle performance 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.
Recommended or required readings
Lecture notes
- Copy of slides (in English)
- Text book (in French)
Reference books (in English):
- T. Gillespie. AA« Fundamentals of vehicle Dynamics AA», 1992, Society of Automotive Engineers (SAE)
- W. Milliken & D. Milliken. AA« Race Car Vehicle Dynamics AA», 1995, Society of Automotive Engineers (SAE)
- R. Bosch. AA« Automotive Handbook AA». 5th edition. 2002. Society of Automotive Engineers (SAE)
- J.Y. Wong. AA« Theory of Ground Vehicles AA». John Wiley & sons. 1993 (2nd edition) 2001 (3rd edition).
- G. Genta."Motor Vehicle Dynamics. Modeling and Simulation". World Scientific. 1997.
Assessment methods and criteria
- Oral exam (theory: 40 %). Students can handle a summary of 4 pages both side hand written.
- Wirtten examen (exercices: 30%). The exercise is soved simultaneously with the theory examen.
- 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
Adaptation of teaching commitments following the COVID-19 pandemic for the May-June 2020 session
Teaching methods implemented : distance-learning
Due to epidemic crisis, exam conditions will be modified to account for a possible late confinement and to anticipate difficulties for some students (especially Erasmus students) to participate in person to the exam.
We have also been forced to modify the teaching procedure switching from in presence class to remote lecturing using podcast.
Lectures and exercises will be recorded and available to you on the university's website. Discussion forums will be open and virtual classroom sessions will be organized.
We also have to comply with the guidelines proposed by the University authorities who suggest to base the evaluation as much as possible on home works performed during the year and to substitute written exams by oral exams which could be (if necessary) done using electronic communication systems.
Therefore, we have modified the agenda of the course (see attachment). A lecture will be given on April 09, while the week of Thursday April 16 will be left blank (Eastern break). There will be a slippage of one week of all lectures. The lecture about Crashworthiness will not be seen this year but postponed to the course MECA0063 Vehicle Architecture, which is available as an elective course that can be taken during autumn semester. This will allow us to close the last lecture on Thursday May 7. The week of May 14 is also left blank apart from a Question and Answer session to help students to solve their homework exercises.
Assessment subjects
Session June
The evaluation for the first session (June 2020) will be based on 1/ the homeworks you will carry out at home and 2/ an oral defense in June.
There will be 4 homeworks (we added one short homework) and a lab report:
- Chassis dynamometer report: Done
- HW1 about vehicle performance and energy consumption simulation: Deadline April 9.
- HW2: analytical exercises on steady state cornering: Deadline May 1st.
- HW3: analytical exercises on steady state cornering including roll, camber and compliance effects. Deadline May 20.
- HW4: analytical exercises on ride and vertical comfort: Deadline May 20.
Final mark will reflect, the written evaluation of the reports and homeworks and the oral presentation and discussion with the professors. An average formula will be proposed.
Session September
If sanitary conditions allow it, the second session will be classically based on the evaluation of the homework and lab reports and an oral exam according to the pedagogical contract. The oral exam includes one question about the theory and one exercise to be solved during the half day session.
Assessment methods
June session
The Defence of the projects will take place using SKYPE or LIFSIZE.
The defense in June is the opportunity to clarify hard points and to discuss the hypotheses on which rely your homework. The defense will last around 30 minutes per student. The students will have to prepare a power point show at home that summarizes their major results of their homeworks. After presenting their power point during 15 minutes to the professors, there will be a discussions and question time with the professors. During the discussion, the students may be invited to develop any theoretical aspects used in the projects to prove their mastering of the theory used in the exercise. To this end the students can use their lecture notes, but no delay/no preparation is accepted to answer. The students may be invited to justify, comment, analyze any results they included in their homework.
Final mark will reflect, the written evaluation of the reports and homeworks and the oral presentation and discussion with the professors. An average formula will be proposed.
Session September
If sanitary conditions allow it, the second session will be classically based on the evaluation of the homework and lab reports and an oral exam according to the pedagogical contract. The oral exam includes one question about the theory and one exercise to be solved during the half day session.
Contacts
Pierre Duysinx
email: p.duysinx@uliege.be
Mobile phone: +32 475 98 22 87
Acronyme SKYPE: pierreduysinx
Link LIFESIZE: https://call.lifesizecloud.com/1230571
Adaptation of teaching commitments following the COVID-19 pandemic for the Aug-Sept 2020 session
Assessment subjects
Same chapters as in June 2020
Assessment methods
Oral exam using LIFESIZE visio conference platform
Contacts
Pierre Duysinx
email: p.duysinx@uliege.be
Mobile phone: +32 475 98 22 87
Acronyme SKYPE: pierreduysinx
Link LIFESIZE: https://call.lifesizecloud.com/1230571