The objective of this course is to introduce to the design of a vehicle bodywork considering the main functional and regulatory constraints. The vast number of different topics require a system level interdisciplinary approach including ergonomics, noise and vibration, structure analysis and passive safety, aerodynamic simulation and testing.
The body of a vehicle is characterized by several functions from giving proper comfort to the passengers to host the powertrain, chassis and suspension systems, achieving proper aerodynamic performances, and guaranteeing the safety of the passengers and other road users. The design of such system requires to the automotive engineer the knowledge of the many functional requirements and mutual constraints. The objective of this course is to introduce to the design of a vehicle bodywork considering the main functional and regulatory constraints, also considering the consolidated trend towards vehicle electrification and increasing levels of driver's assistance systems. The vast number of different topics require a system level interdisciplinary approach including ergonomics, noise and vibration, structure analysis and passive safety, aerodynamic simulation and testing.
Knowledge: Knowledge of Vehicle postural ergonomics, accessibility, direct and indirect visibility, structure solutions adopted for the of passenger cars and light duty vehicles and methods for the analysis of the stress and strain. Knowledge of the loads (external and internal) during operation and during crash events. Sources of noise and vibration, behavior of the vehicle structure under dynamic excitation. Human sensitivity to noise and vibration. Analysis of the aerodynamic and aero-acoustic field, simulation techniques using computational fluid dynamics and wind tunnel experimental measurements. Injury criteria, impact testing procedures following regulatory and rating procedures, structural solutions for crash energy dissipation. Restraint systems.
Skills: Capability to define the vehicle packaging considering the occupants ergonomics, visibility, accessibility and structural constraints. Capability to setup a vehicle structure and analyze its main structural performances in terms of stiffness (torsional and bending), dynamic responses such as mode shapes, natural frequencies and frequency response functions. Analyze by finite element tools the response of the vehicle structure under the effect of the dynamic loads acting on it. Optimize the aerodynamic shape to reduce the drag and insure the functionality of the cooling and air conditioning system. Understand the main constraints coming from crashworthiness regulations and design or specify the subsystems dedicated to insure an adequate level of passive safety.
At the end of the course the student will be able to:
- Analyse and understand the vehicle postural ergonomics, accessibility, direct and indirect visibility, structure solutions adopted for the of passenger cars and light duty vehicles with conventional, electric and hybrid powertrain, methods for the analysis of the stress and strain. - Capability to define the vehicle packaging considering the occupants ergonomics, visibility, accessibility and structural constraints.
- Determine the the loads (external and internal) during operation and during crash events.
- Capability to setup a vehicle structure and analyze its main structural performances in terms of stiffness (torsional and bending), dynamic responses such as mode shapes, natural frequencies and frequency response functions.
- Analyse and understand the sources of noise and vibration, and the behavior of the vehicle structure under dynamic excitation and the consequences on the passengers comfort.
- Analyze by finite element tools the response of the vehicle structure under the effect of the dynamic loads acting on it.
- Know injury criteria, impact testing procedures following regulatory and rating procedures, structural solutions for crash energy dissipation. Restraint systems.
- Understand the main constraints coming from crashworthiness regulations and design or specify the subsystems dedicated to insure an adequate level of passive safety.
- Analyse and understand the aerodynamic and aero-acoustic field,
- Model and predict the aerodynamic performances by simulation techniques based on computational fluid dynamics and wind tunnel experimental measurements.
- Optimize the aerodynamic shape to reduce the drag and insure the functionality of the cooling and air conditioning system.
Motor Vehicle Design, Machine Design, Applied Mechanics, Fundamentals of Strength of Materials. Fluid mechanics, Numerical Modelling.
Prerequisite for understanding the contents of this module are:
- understanding technical drawings (from Engineering drawing),
- knowledge of kinematic system analysis (from Applied Mechanics)
- Knowledge of longitudinal and lateral vehicle dynamics (from Motor Vehicle Design)
- Knowledge of vehicle subsystems such as suspensions, steering and braking system. (from Motor Vehicle Design)
- knowledge of equilibrium analysis in quasi static and dynamic conditions (from Applied Mechanics and Fundamentals of strength of materials)
- knowledge of vibration analysis of lumped parameter mechanical systems (from Applied Mechanics).
- knowledge of structural analysis (from Fundamentals of strength of materials).
1 - Introduction (1,5 h)
Prerequistes and functions of the motor vehicle from the bodywork point of view.
2 – Vehicle packaging (9)
Ergonomics and posture
Percentiles and manikins for packaging
Main constraint to interior packaging coming from vehicle body structure: wheel arches, tunnel, firewall, pedals, underbody.
Seating position and seat comfort
Accessibility to the vehicle and to commands
Direct and indirect visibility
3 – Structure (10,5 h)
General vehicle structure architecture for different vehicle types and with different powertrains.
Reference load cases: loads coming from manoeuvres and obstacles, internal loads due to powertrain, suspensions and safety belts; loads on bodywork surface.
Simplified model of the car structure when subject to internal and external loads.
Structural surface method to analyze torsional and flexural behavior of open and closed chassis architectures.
Structural analysis of monocoque configuration: underbody types and evaluation of their torsional stiffness. H, I, X, ladder frame analysis. Influence of open or closed cross section beams.
4 – Noise and vibration (10,5 h)
Vibration and noise sources from powertrain, wheels, aerodynamic noise.
Introduction to the dynamic behavior of the bodywork and modal analysis.
Vibration response and attenuation.
5 – Passive safety (7,5 h)
Injury criteria, HIC, tibia index, neck, viscous criteria.
Role of restraint system and main parameters affecting the occupants accelerations during a crash.
Crashes of small intensity: Insurance tests, tests on bumpers.
High speed crash tests for homologation and rating.
6 - Introduction to vehicle aerodynamics (6 h)
Equations governing uncompressible fluids.
Limited laminar and turbulent layers
Aerodynamic resistance from friction and pressure.
7 - Aerodynamic resistance (10,5h)
Contributions to the aerodynamic resistance.
Flow structure around squat bodies.
Effect on consumption and performance.
8 - Aerodynamic effects on vehicle functionality (7,5h)
Aerodynamic noise.
Stability with lateral wind.
Engine cooling
Brake cooling.
Soiling and dispersion of exhaust fumes.
9 - Experimental aerodynamics (7,5 h)
Automobile wind tunnels.
Tests on scaled models.
Measurement of the aerodynamic and aerodynamic forces and moments.
Techniques for measuring the fluid-dynamic variables (pressure, speed, heat cables, LDV, PIV).
Measurement of aerodynamic noise.
Measurement of air flows under the bonnet
Road tests.
10 - Computational aerodynamics (9 h)
Numeric methods for equations of fluid motion.
Calculations grids and their creations based on CAD geometry.
Turbulence models.
Boundary conditions.
Elaborations and visualization of the results.
1. Introduction: aims and contents, suggested textbooks and exam procedure.
2 Vehicle packaging (0.5 CFU)
Ergonomics and posture
Percentiles and manikins for packaging
Main constraint to interior packaging coming from vehicle body structure: wheel arches, tunnel, firewall, pedals, underbody.
Seating position and seat comfort
Accessibility to the vehicle and to commands
Direct and indirect visibility
3 Structure (1CFU)
General vehicle structure architecture for different vehicle types and with conventional, hybrid and electric powertrains.
Reference load cases: loads coming from manoeuvres and obstacles, internal loads due to powertrain, suspensions and safety belts; loads on bodywork surface.
Simplified model of the car structure when subject to internal and external loads.
Structural surface method to analyze torsional and flexural behavior of open and closed chassis architectures.
Structural analysis of monocoque configuration: underbody types and evaluation of their torsional stiffness. H, I, X, ladder frame analysis. Influence of open or closed cross section beams.
4 Noise and vibration (1CFU)
Vibration and noise sources from powertrain, wheels, aerodynamic noise.
Introduction to the dynamic behavior of the bodywork and modal analysis.
Vibration response and attenuation.
5 Passive safety (1CFU)
Injury criteria, HIC, tibia index, neck, viscous criteria.
Role of restraint system and main parameters affecting the occupants accelerations during a crash.
Crashes of small intensity: Insurance tests, tests on bumpers.
High speed crash tests for homologation and rating.
6 - Introduction to vehicle aerodynamics (0.5CFU)
Equations governing uncompressible fluids.
Limited laminar and turbulent layers
Aerodynamic resistance from friction and pressure.
7 - Aerodynamic resistance (1CFU)
Contributions to the aerodynamic resistance.
Flow structure around squat bodies.
Effect on consumption and performance.
8 - Aerodynamic effects on vehicle functionality (1CFU)
Aerodynamic noise.
Stability with lateral wind.
Engine cooling
Brake cooling.
Soiling and dispersion of exhaust fumes.
9 - Experimental aerodynamics (1CFU)
Automobile wind tunnels.
Tests on scaled models.
Measurement of the aerodynamic and aerodynamic forces and moments.
Techniques for measuring the fluid-dynamic variables (pressure, speed, heat cables, LDV, PIV).
Measurement of aerodynamic noise.
Measurement of air flows under the bonnet
Road tests.
10 - Computational aerodynamics (1CFU)
Numeric methods for equations of fluid motion.
Calculations grids and their creations based on CAD geometry.
Turbulence models.
Boundary conditions.
Elaborations and visualization of the results.
The course is organised as follows:
Lessons in classroom: (51 hours)
Exercises in classroom: the exercises are organized in projects about the following topics: vehicle packaging, torsional stiffness evaluation of frames.
Exercises in laboratory: CFD analyses will be performed in the Information Technology laboratories (23 hours).
Visits: Wind Tunnel experimental facility, experimental facility for passive safety assessments (6 hours)
In a.y. 2020/21 the lessons and exercises will be held in the form of virtual classooms by means of the BBB platform. All virtual classrooms will be recorded and made available on Portale della Didattica. A in the presence exercise session will be made available each week for a number of students according to the safety regulations and on the availability of classrooms.
The course is organised as follows:
Lessons in classroom: (51 hours)
Exercises in classroom: (23 hours). The exercises are organized in projects about the following topics: vehicle packaging, torsional stiffness evaluation of frames, modal analysis.
Exercises in laboratory: CFD analyses will be performed in the LAIB
Visits: (6 hours). Wind Tunnel experimental facility, experimental facility for passive safety assessments
The projects are carried on in teams of typically 3-4 students each.
The exercise work will be documented by the teams by means of reports that will be evaluated and contribute to the final score.
In a.y. 2021/22 the lessons and exercises will be held in presence. Virtual classroom will be made available at the same time, video-recorded, and made available on Portale della Didattica.
L. Morello, L. Rosti Rossini, G. Pia, A. Tonoli, “The Automotive Body”, Voll, I and II, Springer, 2011.
J. Fenton, "Handbook of Vehicle Design Analysis", SAE, 1999 .
W. Karwowsky, "Automotive Ergonomics", Taylor & Francis, 1993 .
J. Happian-Smith e altri, "An Introduction to Modern Vehicle Design", SAE, 2002 .
T. Gillespie, "Fundamentals of Vehicle Dynamics", SAE, 1999.
Hucho W. H. – Aerodynamics of Road Vehicles.
Pope-Rae – Low Speed Wind Tunnel Testing.
The teaching material needed for preparing the exam is all made available on Portale della Didattica. It includes slides, notes, and recorded virtual classrooms.
Further reading for gaining a deeper insight can be found in the following literature:
L. Morello, L. Rosti Rossini, G. Pia, A. Tonoli, “The Automotive Body”, Voll, I and II, Springer, 2011.
J. Fenton, "Handbook of Vehicle Design Analysis", SAE, 1999 .
W. Karwowsky, "Automotive Ergonomics", Taylor & Francis, 1993 .
J. Happian-Smith e altri, "An Introduction to Modern Vehicle Design", SAE, 2002 .
T. Gillespie, "Fundamentals of Vehicle Dynamics", SAE, 1999.
Hucho W. H. – Aerodynamics of Road Vehicles.
Pope-Rae – Low Speed Wind Tunnel Testing.
Modalità di esame: Test informatizzato in laboratorio; Elaborato progettuale in gruppo;
Exam: Computer lab-based test; Group project;
...
The exam requires the student to know the following topics
- vehicle packaging considering the occupants ergonomics, accessibility and structural constraints.
- Direct and indirect visibility according to EU and SAE regulations,
- Capability to determine the quasi static longitudinal, lateral and torsional loads acting on the vehicle in operating conditions.
- Capability to determine the internal loads from suspensions and powertrain.
- Knowledge of the main a vehicle structure architectures of passenger cars and their main structural performances.
- Capability to analyze the load distribution in frames and box structures under the effect of bending and torsional loads.
- Knowledge about the dynamic responses and human sensitivity to vibration, modal analysis and modal reduction, natural frequencies and frequency response functions.
- Injury criteria, impact testing procedures following regulatory and rating procedures, structural solutions for crash energy dissipation and estimation of their characteristics. Role of the restraint systems.
- Optimize the aerodynamic shape to reduce the drag and insure the functionality of the cooling and air conditioning system.
- Wind tunnel testing and measurement techniques to evaluate different aerodynamic performances.
- Methodologies for the analysis of the aerodynamic performances by means of Computational Fluid Dynamic tools.
The aim of the exam is to verify if and in what measure the learning outcomes are consistent with the expected ones as described above. The exam is conceived to verify the knowledge acquired in the field of the vehicle packaging and visibility, vehicle structure, noise and vibration, aerodynamics, aerodynamic testing and computational fluid dynamics.
The exam is also aimed to verify the capability of the student to elaborate the given knowledge and elaborate it to obtain results and allow to take personal decisions in the field of vehicle body design. This is obtained by the evaluation of the exercise reports prepared during the semester. Additionally one part of the written exam is devoted to numerical exercises.
Exam rules and procedure
Written exam
The written exam will consist in an online written test performed in LAIB or on paper in classroom with 30 multiple choice questions on the theory and 5 short numerical questions about the exercise classes.
They will be split as follows:
Multiple choice:
CBD: 14 questions, 1 correct answer per question, 1 marks per correct answer, -0.5 marks per wrong answer, 0 marks per no answer
AERO: 16 questions, 2 correct answer per question, 0.5 marks per correct answer, -0.25 marks per wrong answer, 0 marks per no answer
Numerical questions
Multiple choice:
CBD: 5 questions, 2 marks if the result is within 2% tolerance, 0 marks if out of tolerance interval.
Aero: no numerical questions
The result of multiple-choice questions and numerical exercise sums to a maximum of 40 points. This result will be rescaled to a max written score of 27/30.
Multiple choice questions and numerical questions will be grouped in one session. The written score is one, including the CBD and Aero parts that are not evaluated separately.
During the exam
• exchange information among you is not permitted by any means. To this end the application will activate the video-camera and we and the system itself will detect activities not strictly related to answering the questions.
• use of cell phone is forbidden and you will be asked to leave it far from your desk.
• use of any written material is forbidden as well.
• numerical computations can be done just by a simple scientific calculator or by means of the scientific calculator available in the Exam web interface.
• Scrolling up/down between questions is possible.
Exercise reports
The CBD and Aero repots are discussed orally with the team and will be evaluated as follows.
CBD: 3 reports, max 3 marks for the 3 reports, reports are compulsory.
AERO CFD: 1 report, 0 marks, report is compulsory.
AERO work group: 1 report, 3 marks, optional
Reports are due 1 week before the exam. This means that the reports have to be submitted one week before the exam call that will be attempted first by one of you. If you are the first of your team to attempt the exam in the second call, then your team has to submit the reports one week before the second call.
Note2: the team members that attempt the exam in later calls have not to resubmit the reports.
Note 3: if you already submitted the reports in previous academic years and had them evaluated, you do not need to resubmit them this a.y.
A max of 6 marks can then be reached from CBD reports or Aero workgroup discussion. These marks are added to the written score. The result is saturated at 30. Laude can be obtained with additional oral examination.
We ask you then to upload in the “Elaborati” section of CBD&Aero Portale della Didattica webpage your project reports. Frontpage must include all the names of the team members. CBD: Submit just one report per group in pdf format with following file naming convention:
Sxxxx-Syyyyy-Szzzz.pdf
Where xxxx, yyyy, zzzz are the student IDs of each team member.
• .doc or other formats will not be evaluated.
• Files sent by email will not be evaluated.
Oral exam
Optional oral examinations in presence will be possible just for cumulative written+reports scores higher or equal to 25 or in cases left to the teacher's decision, such as an unclear result of the written. The oral examination consists in a number of at least three questions covering the course program for a further assessment of the expected learning outcomes. The student will be asked to answer giving priority to quantitative arguments, graphical representations, and analytical reasoning. The oral examination can lead to an increment as well as a reduction of the score obtained in the written.
Gli studenti e le studentesse con disabilità o con Disturbi Specifici di Apprendimento (DSA), oltre alla segnalazione tramite procedura informatizzata, sono invitati a comunicare anche direttamente al/la docente titolare dell'insegnamento, con un preavviso non inferiore ad una settimana dall'avvio della sessione d'esame, gli strumenti compensativi concordati con l'Unità Special Needs, al fine di permettere al/la docente la declinazione più idonea in riferimento alla specifica tipologia di esame.
Exam: Computer lab-based test; Group project;
The exam requires the student to know the following topics
- vehicle packaging considering the occupants ergonomics, accessibility and structural constraints.
- Direct and indirect visibility according to EU and SAE regulations,
- Capability to determine the quasi static longitudinal, lateral and torsional loads acting on the vehicle in operating conditions.
- Capability to determine the internal loads from suspensions and powertrain.
- Knowledge of the main a vehicle structure architectures of passenger cars and their main structural performances.
- Capability to analyze the load distribution in frames and box structures under the effect of bending and torsional loads.
- Knowledge about the dynamic responses and human sensitivity to vibration, modal analysis and modal reduction, natural frequencies and frequency response functions.
- Injury criteria, impact testing procedures following regulatory and rating procedures, structural solutions for crash energy dissipation and estimation of their characteristics. Role of the restraint systems.
- Optimize the aerodynamic shape to reduce the drag and insure the functionality of the cooling and air conditioning system.
- Wind tunnel testing and measurement techniques to evaluate different aerodynamic performances.
- Methodologies for the analysis of the aerodynamic performances by means of Computational Fluid Dynamic tools.
The aim of the exam is to verify if and in what measure the learning outcomes are consistent with the expected ones as described above. The exam is conceived to verify the knowledge acquired in the field of the vehicle packaging and visibility, vehicle structure, noise and vibration, aerodynamics, aerodynamic testing and computational fluid dynamics.
The exam is also aimed to verify the capability of the student to elaborate the given knowledge and elaborate it to obtain results and allow to take personal decisions in the field of vehicle body design. This is obtained by the evaluation of the exercise reports prepared during the semester. Additionally one part of the written exam is devoted to numerical exercises.
Exam rules and procedure
Written exam
The written exam will consist in an online written test performed in LAIB or on paper in classroom with 30 multiple choice questions on the theory and 5 short numerical questions about the exercise classes.
They will be split as follows:
Multiple choice:
CBD: 14 questions, 1 correct answer per question, 1 marks per correct answer, -0.5 marks per wrong answer, 0 marks per no answer
AERO: 16 questions, 2 correct answer per question, 0.5 marks per correct answer, -0.25 marks per wrong answer, 0 marks per no answer
Numerical questions
Multiple choice:
CBD: 5 questions, 2 marks if the result is within 2% tolerance, 0 marks if out of tolerance interval.
Aero: no numerical questions
The result of multiple-choice questions and numerical exercise sums to a maximum of 40 points. This result will be rescaled to a max written score of 27/30.
Multiple choice questions and numerical questions will be grouped in one session. The written score is one, including the CBD and Aero parts that are not evaluated separately.
During the exam
• exchange information among you is not permitted by any means. To this end the application will activate the video-camera and we and the system itself will detect activities not strictly related to answering the questions.
• use of cell phone is forbidden and you will be asked to leave it far from your desk.
• use of any written material is forbidden as well.
• numerical computations can be done just by a simple scientific calculator or by means of the scientific calculator available in the Exam web interface.
• Scrolling up/down between questions is possible.
Exercise reports
The CBD and Aero repots are discussed orally with the team and will be evaluated as follows.
CBD: 3 reports, max 3 marks for the 3 reports, reports are compulsory.
AERO CFD: 1 report, 0 marks, report is compulsory.
AERO work group: 1 report, 3 marks, optional
Reports are due 1 week before the exam. This means that the reports have to be submitted one week before the exam call that will be attempted first by one of you. If you are the first of your team to attempt the exam in the second call, then your team has to submit the reports one week before the second call.
Note2: the team members that attempt the exam in later calls have not to resubmit the reports.
Note 3: if you already submitted the reports in previous academic years and had them evaluated, you do not need to resubmit them this a.y.
A max of 6 marks can then be reached from CBD reports or Aero workgroup discussion. These marks are added to the written score. The result is saturated at 30. Laude can be obtained with additional oral examination.
We ask you then to upload in the “Elaborati” section of CBD&Aero Portale della Didattica webpage your project reports. Frontpage must include all the names of the team members. CBD: Submit just one report per group in pdf format with following file naming convention:
Sxxxx-Syyyyy-Szzzz.pdf
Where xxxx, yyyy, zzzz are the student IDs of each team member.
• .doc or other formats will not be evaluated.
• Files sent by email will not be evaluated.
Oral exam
Optional oral examinations in presence will be possible just for cumulative written+reports scores higher or equal to 25 or in cases left to the teacher's decision, such as an unclear result of the written. The oral examination consists in a number of at least three questions covering the course program for a further assessment of the expected learning outcomes. The student will be asked to answer giving priority to quantitative arguments, graphical representations, and analytical reasoning. The oral examination can lead to an increment as well as a reduction of the score obtained in the written.
In addition to the message sent by the online system, students with disabilities or Specific Learning Disorders (SLD) are invited to directly inform the professor in charge of the course about the special arrangements for the exam that have been agreed with the Special Needs Unit. The professor has to be informed at least one week before the beginning of the examination session in order to provide students with the most suitable arrangements for each specific type of exam.
Modalità di esame: Prova scritta tramite PC con l'utilizzo della piattaforma di ateneo; Elaborato progettuale in gruppo;
Exam rules and procedure
The Motor Vehicle Design exam consists of 30 multiple choice questions and 8 numerical exercises.
Each multiple-choice question has just one correct answer. The numerical exercises require to solve a numerical problem similar to those shown during the exercise lessons.
The time to complete the exam is 2 hours.
During the exam it is possible to use just a simple scientific calculator, pen and paper or the calculator available in Respondus interface.
Exchange information among students is not permitted by any means.
Use of multimedia devices such as cell phone, tablet, pc, smart watch is not allowed.
Use of any written material such as notes, textbooks is not allowed.
Scoring:
The total exam score is composed by the evaluation of the written exam, the exercise reports and an optional oral as follows
Written exam
The written exam is composed of multiple choice questions, numerical exercises, and exercise reports
30 m.c.questions Correct answer: + 1 point
No answer: 0 points
Wrong answer: - 1/2 points
8 numerical exercises Correct answer: +2 points
No or wrong answer: 0 points
The total score of the multiple-choice questions and the numerical exercises is rescaled linearly to 32/30.
The four exercise reports prepared during the semester are evaluated with a score from 0 to 3 points that are added to the score of the multiple-choice questions and the numerical exercises (after rescaling). The exercise reports have to be uploaded in pdf form on the “elaborati” section of the Portale della Didattica at least one week before the written exam.
Score of written exam=(score of multiple choice + score of numerical exercise)*32/46 + score of exercise reports.
The exam is overcome successfully for scores higher than 18/30.
The scores are uploaded on Portale della Didattica within a week from the written exam.
The corrected written exam can be viewed during a dedicated session that is scheduled after the publication of the scores. The date is noticed by means of the Portale della Didattica.
Optional oral examinations is possible just for scores of the written exam higher or equal to 27/30.
Exam: Computer-based written test using the PoliTo platform; Group project;
The exam requires the student to know the following topics
- vehicle packaging considering the occupants ergonomics, accessibility and structural constraints.
- Direct and indirect visibility according to EU and SAE regulations,
- Capability to determine the quasi static longitudinal, lateral and torsional loads acting on the vehicle in operating conditions.
- Capability to determine the internal loads from suspensions and powertrain.
- Knowledge of the main a vehicle structure architectures of passenger cars and their main structural performances.
- Capability to analyze the load distribution in frames and box structures under the effect of bending and torsional loads.
- Knowledge about the dynamic responses and human sensitivity to vibration, modal analysis and modal reduction, natural frequencies and frequency response functions.
- Injury criteria, impact testing procedures following regulatory and rating procedures, structural solutions for crash energy dissipation and estimation of their characteristics. Role of the restraint systems.
- Optimize the aerodynamic shape to reduce the drag and insure the functionality of the cooling and air conditioning system.
- Wind tunnel testing and measurement techniques to evaluate different aerodynamic performances.
- Methodologies for the analysis of the aerodynamic performances by means of Computational Fluid Dynamic tools.
The aim of the exam is to verify if and in what measure the learning outcomes are consistent with the expected ones as described above. The exam is conceived to verify the knowledge acquired in the field of the vehicle packaging and visibility, vehicle structure, noise and vibration, aerodynamics, aerodynamic testing and computational fluid dynamics.
The exam is also aimed to verify the capability of the student to elaborate the given knowledge and elaborate it to obtain results and allow to take personal decisions in the field of vehicle body design. This is obtained by the evaluation of the exercise reports prepared during the semester. Additionally one part of the written exam is devoted to numerical exercises.
Exam rules and procedure
Written exam
The written exam will consist in an online written test using the Respondus platform with 30 multiple choice questions on the theory and 5 short numerical questions about the exercise classes.
They will be split as follows:
Multiple choice:
CBD: 14 questions, 1 correct answer per question, 1 marks per correct answer, -0.5 marks per wrong answer, 0 marks per no answer
AERO: 16 questions, 2 correct answer per question, 0.5 marks per correct answer, -0.25 marks per wrong answer, 0 marks per no answer
Numerical questions
Multiple choice:
CBD: 5 questions, 2 marks if the result is within 2% tolerance, 0 marks if out of tolerance interval.
Aero: no numerical questions
The result of multiple-choice questions and numerical exercise sums to a maximum of 40 points. This result will be rescaled to a max written score of 27/30.
Multiple choice questions and numerical questions will be grouped in one Exam+Respundus session. The written score is one, including the CBD and Aero parts that are not evaluated separately.
The exam platform will lock your desktop so you will not be able to activate other applications apart from the browser window.
• exchange information among you is not permitted by any means. To this end the application will activate the video-camera and we and the system itself will detect activities not strictly related to answering the questions.
• use of cell phone is forbidden and you will be asked to leave it far from your desk.
• use of any written material is forbidden as well.
• numerical computations can be done just by a simple scientific calculator or by means of the scientific calculator available in the Exam web interface.
• Scrolling up/down between questions is possible.
Exercise reports
The CBD and Aero repots are discussed in remote with the team and will be evaluated as follows.
CBD: 3 reports, max 3 marks for the 3 reports, reports are compulsory.
AERO CFD: 1 report, 0 marks, report is compulsory.
AERO work group: 1 report, 3 marks, optional
Reports are due 1 week before the exam. This means that the reports have to be submitted one week before the exam call that will be attempted first by one of you. If you are the first of your team to attempt the exam in the second call, then your team has to submit the reports one week before the second call.
Note2: the team members that attempt the exam in later calls have not to resubmit the reports.
Note 3: if you already submitted the reports in previous academic years and had them evaluated, you do not need to resubmit them this a.y.
A max of 6 marks can then be reached from CBD reports or Aero workgroup discussion. These marks are added to the written score. The result is saturated at 30. Laude can be obtained with additional oral examination.
We ask you then to upload in the “Elaborati” section of CBD&Aero Portale della Didattica webpage your project reports. Frontpage must include all the names of the team members. CBD: Submit just one report per group in pdf format with following file naming convention:
Sxxxx-Syyyyy-Szzzz.pdf
Where xxxx, yyyy, zzzz are the student IDs of each team member.
• .doc or other formats will not be evaluated.
• Files sent by email will not be evaluated.
Oral exam
Optional oral examinations in remote will be possible just for cumulative written+reports scores higher or equal to 25 or in cases left to the teacher's decision, such as an unclear result of the written. The oral examination consists in a number of at least three questions covering the course program for a further assessment of the expected learning outcomes. The student will be asked to answer giving priority to quantitative arguments, graphical representations, and analytical reasoning. The oral examination can lead to an increment as well as a reduction of the score obtained in the written.
Modalità di esame: Prova scritta (in aula); Prova orale facoltativa; Elaborato scritto individuale;
Exam rules and procedure
The Motor Vehicle Design exam consists of 30 multiple choice questions and 8 numerical exercises.
Each multiple-choice question has just one correct answer. The numerical exercises require to solve a numerical problem similar to those shown during the exercise lessons.
The time to complete the exam is 2 hours.
During the exam it is possible to use just a simple scientific calculator, pen and paper or the calculator available in Respondus interface.
Exchange information among students is not permitted by any means.
Use of multimedia devices such as cell phone, tablet, pc, smart watch is not allowed.
Use of any written material such as notes, textbooks is not allowed.
Scoring:
The total exam score is composed by the evaluation of the written exam, the exercise reports and an optional oral as follows
Written exam
The written exam is composed of multiple choice questions, numerical exercises, and exercise reports
30 m.c.questions Correct answer: + 1 point
No answer: 0 points
Wrong answer: - 1/2 points
8 numerical exercises Correct answer: +2 points
No or wrong answer: 0 points
The total score of the multiple-choice questions and the numerical exercises is rescaled linearly to 32/30.
The four exercise reports prepared during the semester are evaluated with a score from 0 to 3 points that are added to the score of the multiple-choice questions and the numerical exercises (after rescaling). The exercise reports have to be uploaded in pdf form on the “elaborati” section of the Portale della Didattica at least one week before the written exam.
Score of written exam=(score of multiple choice + score of numerical exercise)*32/46 + score of exercise reports.
The exam is overcome successfully for scores higher than 18/30.
The scores are uploaded on Portale della Didattica within a week from the written exam.
The corrected written exam can be viewed during a dedicated session that is scheduled after the publication of the scores. The date is noticed by means of the Portale della Didattica.
Optional oral examinations is possible just for scores of the written exam higher or equal to 27/30.
Exam: Written test; Optional oral exam; Individual essay;
The exam requires the student to know the following topics
- vehicle packaging considering the occupants ergonomics, accessibility and structural constraints.
- Direct and indirect visibility according to EU and SAE regulations,
- Capability to determine the quasi static longitudinal, lateral and torsional loads acting on the vehicle in operating conditions.
- Capability to determine the internal loads from suspensions and powertrain.
- Knowledge of the main a vehicle structure architectures of passenger cars and their main structural performances.
- Capability to analyze the load distribution in frames and box structures under the effect of bending and torsional loads.
- Knowledge about the dynamic responses and human sensitivity to vibration, modal analysis and modal reduction, natural frequencies and frequency response functions.
- Injury criteria, impact testing procedures following regulatory and rating procedures, structural solutions for crash energy dissipation and estimation of their characteristics. Role of the restraint systems.
- Optimize the aerodynamic shape to reduce the drag and insure the functionality of the cooling and air conditioning system.
- Wind tunnel testing and measurement techniques to evaluate different aerodynamic performances.
- Methodologies for the analysis of the aerodynamic performances by means of Computational Fluid Dynamic tools.
The aim of the exam is to verify if and in what measure the learning outcomes are consistent with the expected ones as described above. The exam is conceived to verify the knowledge acquired in the field of the vehicle packaging and visibility, vehicle structure, noise and vibration, aerodynamics, aerodynamic testing and computational fluid dynamics.
The exam is also aimed to verify the capability of the student to elaborate the given knowledge and elaborate it to obtain results and allow to take personal decisions in the field of vehicle body design. This is obtained by the evaluation of the exercise reports prepared during the semester. Additionally one part of the written exam is devoted to numerical exercises.
Exam rules and procedure
Written exam
The written exam will consist in an online written test on Respondus platform with 30 multiple choice questions on the theory and 5 short numerical questions about the exercise classes.
They will be split as follows:
Multiple choice:
CBD: 14 questions, 1 correct answer per question, 1 marks per correct answer, -0.5 marks per wrong answer, 0 marks per no answer
AERO: 16 questions, 2 correct answer per question, 0.5 marks per correct answer, -0.25 marks per wrong answer, 0 marks per no answer
Numerical questions
Multiple choice:
CBD: 5 questions, 2 marks if the result is within 2% tolerance, 0 marks if out of tolerance interval.
Aero: no numerical questions
The result of multiple-choice questions and numerical exercise sums to a maximum of 40 points. This result will be rescaled to a max written score of 27/30.
Multiple choice questions and numerical questions will be grouped in one Exam+Respundus session. The written score is one, including the CBD and Aero parts that are not evaluated separately.
The exam platform will lock your desktop so you will not be able to activate other applications apart from the browser window.
• exchange information among you is not permitted by any means. To this end the application will activate the video-camera and we and the system itself will detect activities not strictly related to answering the questions.
• use of cell phone is forbidden and you will be asked to leave it far from your desk.
• use of any written material is forbidden as well.
• numerical computations can be done just by a simple scientific calculator or by means of the scientific calculator available in the Exam web interface.
• Scrolling up/down between questions is possible.
Exercise reports
The CBD and Aero repots are discussed in presence or in remote with the team and will be evaluated as follows.
CBD: 3 reports, max 3 marks for the 3 reports, reports are compulsory.
AERO CFD: 1 report, 0 marks, report is compulsory.
AERO work group: 1 report, 3 marks, optional
Reports are due 1 week before the exam. This means that the reports have to be submitted one week before the exam call that will be attempted first by one of you. If you are the first of your team to attempt the exam in the second call, then your team has to submit the reports one week before the second call.
Note2: the team members that attempt the exam in later calls have not to resubmit the reports.
Note 3: if you already submitted the reports in previous academic years and had them evaluated, you do not need to resubmit them this a.y.
A max of 6 marks can then be reached from CBD reports or Aero workgroup discussion. These marks are added to the written score. The result is saturated at 30. Laude can be obtained with additional oral examination.
We ask you then to upload in the “Elaborati” section of CBD&Aero Portale della Didattica webpage your project reports. Frontpage must include all the names of the team members. CBD: Submit just one report per group in pdf format with following file naming convention:
Sxxxx-Syyyyy-Szzzz.pdf
Where xxxx, yyyy, zzzz are the student IDs of each team member.
• .doc or other formats will not be evaluated.
• Files sent by email will not be evaluated.
Oral exam
Optional oral examinations in presence or in remote will be possible just for cumulative written+reports scores higher or equal to 25 or in cases left to the teacher's decision, such as an unclear result of the written. The oral examination consists in a number of at least three questions covering the course program for a further assessment of the expected learning outcomes. The student will be asked to answer giving priority to quantitative arguments, graphical representations, and analytical reasoning. The oral examination can lead to an increment as well as a reduction of the score obtained in the written.