Reconfigurable_Electric_Vehicle

SUMMER AUTOMOTIVE ENGINEERING
PROJECT - 2009
Reconfigurable Electric Vehicle
Institute for Advanced Vehicle Systems
College of Engineering and Computer Science
University of Michigan-Dearborn

Copyright © 2010 by the College of Engineering and Computer Science,
All rights reserved.
Printed in the United States of America by Sheridan Books.
Except as permitted under the United States Copyright Act of 1976, no part of this publication
may be reproduced or distributed in any form or by any means, or stored in a data base or
retrieval system, without the prior written permission of the University of Michigan-Dearborn.
ISBN: 978-0-933691-13-1
Permission to reprint may be obtained by contacting:
Director, Institute for Advanced Vehicle Systems
2066 IAVS
4901 Evergreen Road
Dearborn, MI 48128-1491
Drawings and figures were created by the students of the University of Michigan-Dearborn.
Renderings of the Electric Vehicle Design in the book were created by University of
Michigan-Dearborn students using Bunkspeed HyperShot software.
Published by the College of Engineering and Computer Science,

i
Table of Contents
List of Figures iii
List of Tables. vii
Acknowledgment ix
Preface xi
Executive Summary 1
Chapter 1 - Introduction 3
Chapter 2 - The Project story 5
Chapter 3 - Customer and Functional Requirements 11
Chapter 4 - Concept Description 15
Chapter 5 - Design Process 17
Chapter 6 - Vehicle Design 23
Chapter 7 - Vehicle Packaging 47
Chapter 8 - CAD outputs 55
Chapter 9 - Chassis/Body 61
Chapter 10 - EV Powertrain Design 67
Chapter 11 - Control Systems and their Functions 87
Chapter 12 - Electrical/ Electromechanical Systems 91

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Chapter 13 - Docking Sequence and Driver Interface 95
Chapter 14 - Cost analysis 105
The Next IAVS Driving Project 109
Appendix 1 – Benchmarked Vehicles 111
Appendix 2 – Model Description 117
Appendix 3 – Future Battery Technology 123
Appendix 4 – The Quasiturbine Engine 129
Appendix 5 – Photovoltaic Paint. 135
Appendix 6 – Docking/Undocking Procedure 137

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List of Figures
Figure 4-1 Revolution Concept. 15
Figure 4-2 Vehicle Chunks (modules) 16
Figure 5-1 Quasiturbine Engine 18
Figure 5-2 Transparent Engine Cover 18
Figure 5-3 Diffuser and Flat Under Tray 18
Figure 5-4 Regenerative Shock absorbers 20
Figure 6-1 City Commuter and Mid Size Sedan 23
Figure 6-2 First Sketch 24
Figure 6-3 Subsequent Vehicle Sketches 25
Figure 6-4 Commuter Car Designs 26
Figure 6-5 Sedan Designs 27
Figure 6-6 Alternate Body Styles (Pick-up, SUV and a Raised Wagon) 28
Figure 6-7 Approaches to Connect the Two Modules [(a), (b) showing the cross sectional
view of the connectors,(c) side view of the connector] 29,30
Figure 6-8 Alias Model for the Final Vehicle Design 30,31
Figure 6-9 Clay Model Representation for the Sedan 31
Figure 6-10 Final Rendered Vehicle Designs [Sedan in (a) and (b), Commuter in (c), and
Sedan and Commuter face-to-face in (d)] 32,33
Figure 6-11 Chevy Volt Interior Design 34
Figure 6-12 Chrysler 200 C Concept Instrument Displays 35
Figure 6-13 Lincoln C Interior Design 35

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Figure 6-14 Sketch 1 (Instrument Cluster) 36
Figure 6-15 Sketch 2 (Steering Control) 37
Figure 6-16 Sketch 3 (Center Stack) 37
Figure 6-17 Sketch 4 (Seating Layout) 38
Figure 6-18 Sketch 5 and 6 (Seat Design) 38
Figure 6-19 Sketch 7 (Key Fob) 39
Figure 6-20 (a), (b) Instrument Cluster Concepts 39,40
Figure 6-21 Initial Vehicle Interior Sketches 41
Figure 6-22 Initial Vehicle Interior Concepts 42
Figure 6-23 Head Up Display 43
Figure 6-24 Final Rendered Vehicle Interior Design 44
Figure 7-1 Key Reference Points 47
Figure 7-2 Plan View of the 2010 Ford Fusion (The “Blue rectangle shows overall length
and width) 48
Figure 7-3 Section View of Small Compact Vehicle (shown in “Green”) and the Large
Rear Unit (shown in “Dull Yellow”) [The top “Blue” line shows the overall height of
2010 Ford Fusion] 49
Figure 7-4 Vehicle Concept 50
Figure 7-5 Driver Packaging 51
Figure 7-6 Suspension Packaging 52
Figure 7-7 Li-ion Battery 52
Figure 7-8 Electric Motors 53
Figure 8-1 Initial CAD Designs 55
Figure 8-2 CAD Designs 56

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Figure 8-3 (a) Solidworks Design for Front Suspension System, (b) Solidworks Design for
Rear Suspension, (c) Front unit with the Motors, (d) Rendered Design for Suspensions,
Motors, Motor Cradle, Wheels 56,57
Figure 8-4 (a) Side View, (b) Rear View, (c) Angle View 58
Figure 8-5 Mechianical Connectors (Four connectors will be used to latch front unit to the
rear unit of the vehicle) 59
Figure 9-1 Chassis 61
Figure 9-2 Chassis Design for Two Styles of Vehicles 62
Figure 9-3 Chassis Components 62
Figure 9-4 Battery Sliding In-Out Feature of the Chassis 63
Figure 9-5 Chassis on Wheels 63
Figure 9-6 Chassis with Interiors 64
Figure 9-7 CATIA Model 64
Figure 9-8 Final Rendered Model 65
Figure 10-1 System Configuration for Travel Less than 60 Miles 69
Figure 10-2 System Configuration for Travel Greater than 60 Miles 69
Figure 10-3 Energy Flow while Regenerating 70
Figure 10-4 Concept Representation 71
Figure 10-5 EPA Uraban Driving Cycle 75
Figure 10-6 EPA Highway Driving Cycle 75
Figure 10-7 a) Effect of SOC Change on Battery Weight, b) Effect of SOC Change on
Battery Volume, c) Effect of SOC Change on Required Battery Energy 80,81
Figure 10-8 Effect of SOC on Vehicle Range 82
Figure 10-9 Multi Circuit Connectors 83

vi
Figure 10-10 Engine Combustion Comparison 84
Figure 13-1 Vehicle Present Configuration 95
Figure 13-2 Docking sequence – Stage 2 96
Figure 13-7 Process of Swapping Ends 99

vii
List of Tables
Table 3-1 Functional Requirements 12
Table 6-1 Strengths 45
Table 6-2 Weaknesses 46
Table 10-1 Model Analysis Results 73,74
Table 10-2 SOC Analysis Results 80
Table 10-3 Effect of Available SOC Range on Electric Range 81
Table 14-1 Battery $/KWh 105
Table 14-2 Changes in Battery Technology 106

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ix
Acknowledgement
The team would like to acknowledge Prof. Vivek Bhise for his constant guidance, advice and
supervision; Dr. Roger Shulze for giving us such a great opportunity and also for planning and
administrating this project; Institute of Advanced Vehicle Systems (UMD) and Ford for
providing financial support for this project; Subrata Sengupta, Dean of CECS, UMD for
allowing to do this project and letting the team use university facilities; Ford, GM and Chrysler
for student visits and for providing technical help and consultations.
Team would also like to thank the parents of Justina Ngorka, David Hnatio and Calvin
McKinney for taking interests in the project and for providing their expert opinions and
technical assistance.

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Preface
This past summer was the second time the Institute for Advanced Vehicle Systems (IAVS)
conducted what is becoming known as the Summer Automotive Engineering Experience. This
was a four-month long student project in the College of Engineering and Computer Science
(CECS) at the University of Michigan-Dearborn (UM-Dearborn). The first student project,
conducted during the summer of 2008 was entitled the Model T Challenge, sponsored by Ford
Motor Company. The feedback from the students on the first project was so enthusiastic and
positive that we just had to find a way to do it again. With Ford Motor Company’s help again,
we did.
The theme of the latest student project was the design of an innovative electric car. The student
team consisted of six CECS undergraduate students mentored by three CECS graduate
students, all under the supervision of Professor Vivek Bhise, professor of industrial and
manufacturing systems engineering and a veteran of the first summer’s project. The team was
later joined by two designers from the College for Creative Studies (CCS), one a recent graduate
and the other a current student.
The choice of the design of an electric car for the project was a natural one for several reasons.
First, nearly every car company is working on electrification of the automobile so it makes sense
for us to see how we might help out. We hoped that tapping fresh minds was one way to help.
Young engineering students might have fresh ways of looking at things since they have not yet
learned the “conventional wisdom.” They might take risks that professionals in the automotive
industry cannot because sometimes failure is not an option. Simply put, young engineering
students often don’t know what to fear, and the result just might be an interesting surprise. Did
our student team come up with a wonderful surprise? That is for you, the reader, to decide.
The second reason the choice of the design of an electric car for the project was a natural one is
that IAVS chose for its next driving project the electrification of the automobile. Already several
research projects have been conducted under the IAVS umbrella. Another block of research
projects is planned for early next year. It made sense with the attention IAVS is giving to the
subject of electrification of the automobile that its summer project should be about
electrification as well.
While risk-taking and innovation were strongly encouraged during the student project, this is
not to suggest that the team began the project without a plan or proceeded without direction.
The first thing the team did was create a plan based on a set of customer requirements that had
been created in a graduate student research project prior to the summer engineering project.
The team was instructed come up with a plan to design an electric car that met these customer

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requirements. The challenge for the team was that some of the customer requirements appeared
to be contradictory. For example, the vehicle was to have a range of at least 60 miles for use as a
low-priced commuter but it also had to be capable of going at least 200 miles when desired.
To help the team with its direction the undergraduate students were mentored throughout the
summer by three graduate students; all enrolled in CECS’ masters program in automotive
systems engineering. These graduate students coached the undergraduate students on technical
matters the younger students wouldn’t study for several more years.
As with the Model T Challenge, the latest project greatly enhanced the University of Michigan-
Dearborn’ ability to provide students with outstanding real-world experiences. It was an
exciting learning experience for everyone who participated in it – the undergraduate student
team members, the graduate students who served as mentors and technical advisors, the CCS
designers, for Professor Bhise and me. When our undergraduate and graduate students
complete their degrees and head off to their first jobs they will take with them something rare:
the experience of working on a team to create the advance design of an entire electric vehicle in
just four months. As you will read in the chapters that follow, I think you will agree that the
electric vehicle the University of Michigan-Dearborn student team designed last summer did
indeed meet the customer requirements in a sound engineering way. I think you will also agree
that the design is innovative and full of several interesting surprises.
The university is privileged to have had the support of Ford Motor Company as a sponsor for
this Summer Automotive Engineering Experience. I thank Ford Motor Company for helping to
make this student project possible. I also would like to thank the team; the CECS
undergraduates: Mark Bajor, Craig Cowing, David Hnatio, Calvin McKinney, Justina Nagorka
and Sidharth Vallabhaneni; the CECS graduate students: Aayush Gupta, Heramb Dandekar and
Uday Sharma; the CCS designers: Trevor Greene and Matthew Lisk; and the team’s supervisor,
Professor Vivek Bhise. I am immensely proud of what the team accomplished.
A final note; already a number of team members have urged IAVS to conduct a similar project
next summer. Speaking for IAVS; we will investigate ways to have yet another Summer
Automotive Engineering Experience next summer.
Roger Shulze, Director
Institute for Advanced Vehicle Systems
2009

1
Executive Summary
The objective for this project was to design an innovative electric vehicle which will not only
keep the environment clean but also will satisfy the customer. Thus, before even starting this
project it was very crucial for us to determine the customer wants. And to do that we conducted
a small survey. The QFD matrix was used to translate the customer requirements into
functional requirements which provided the direction for the project. The three areas on which
we focused were: Powertrain, Driver Interface, and Packaging. Along with these, overall vehicle
design was a very obvious and important area we had to focus on. The vehicle had to look good
aesthetically and should also have low aerodynamic drag for better energy consumption.
The concept proposed by the team is a Reconfigurable Electric Vehicle (REV) concept or as
called by the team a “REVolution” concept. It provides customers an option to reconfigure the
vehicle as per their needs. So customer can have a city commuter with a range of 60 miles on
weekdays and a midsize sedan with a range of 350 miles for long family trips on weekends.
This has several advantages or strengths but at the same time it has some weaknesses which
were addressed by the team. The team worked rigorously during the design process and used
several tools such as ALIAS, SOLIDWORKS and CATIA. Bunkspeed was used in final stages
for renderings.
For this vehicle to meet the performance expectations, designing electric powertrain systems
was very important. The city commuter was designed to be a pure BEV (i.e. Battery based
Electric Vehicle) with a range of 60 miles and 0-60 mph acceleration in 8.5 seconds. Two motors
in front wheel drive configuration provided the required traction. When the vehicle is
reconfigured to a midsize sedan, its architecture changes to a 350 mile range extended electric
vehicle with same acceleration performance targets. The vehicle has a Lithium-ion battery
which is currently the best for vehicle applications and promises to get better in coming years.
For range extensions, a quasitubine engine was selected. It is currently in developing stages and
has a potential to be much more efficient than a conventional internal combustion engine.
Another important aspect was vehicle packaging where the team focused on packaging several
key systems. Vehicle packaging basically involved driver/occupants packaging, instrument

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panel packaging, powertrain packaging (which included batteries, motors, power electronics,
quasiturbine engine, generator, fuel tank), and suspension packaging which included both front
and rear suspensions systems. Systems specifications were determined and several CAD
models were developed to package the considered systems in the vehicle space.
Re-configurability was really the crux of the concept. And since the re-configurability brings
complexity, it was important for the team to design the driver / user interface such that systems
could be operated with ease and with little learning and training involved. Swapping of vehicle
modules was designed as an automated process with well designed interfaces. The interfaces
were designed such that driver or user would be informed and guided on every step of the
process. Several warnings have also been built-in with safety considerations to avoid driver
errors and accidents. Interfaces were designed using Microsoft PowerPoint.
Finally, cost estimates were developed for implementation of the “REVolution.” With some
basic assumptions, the cost analysis was conducted, results of which were found to be
reasonable. The vehicle introduction was targeted for 2025 and it is hoped that in the coming
years and advancements in technologies, the costs can be substantially reduced.

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Chapter 1
__________________________________________________________________
INTRODUCTION
______________________________________________________________________________
PROJECT OBJECTIVES
To design a people’s Electric Vehicle for future that will be a silver bullet for all the current
issues and would revolutionize automotive industry.
Specific Design Objectives
a. Develop innovative concepts in developing vehicle package, powertrain, and user
interfaces.
b. Must carry 4-5 adults with luggage.
c. Range of at least 200 miles with at least 60 miles of battery range.
d. Implementable in 8-10 years (MY2020).
PROJECT INTRODUCTION
Have you ever found yourself wishing you could combine unlimited functionality and a great
fuel economy in just one car? The “REVolution” Electric Vehicle Concept fulfills those desires
in an ultimate innovational car design. Its ability to run as a two passenger commuter car and
change into a five passenger sedan, truck, or SUV makes it one of the most efficient automobile
designs to date. The REVolution in its five passenger vehicle form is a range extended vehicle
incorporating a Quasiturbine engine and a generator. The engine allows for an increased travel
distance on a single charge of the batteries to three hundred and fifty miles, from the battery
pack’s original sixty mile range. This concept is aimed at being feasible by the year 2020 and on
road by 2025.

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This concept car has the potential to revolutionize automotive transportation. It gives an owner
the opportunity to use one car in ways that it would otherwise require use of multiple vehicles.
Potential ways in which this model could be introduced to the market are: the ability to own
both, small and extended versions; as well as own the city commuter and rent the range
extender ends based on the style needed, or rental of the small and extended versions. To make
the concept a desirable option for a potential customer, an ownership and/or rental choices
would need to be presented as a cost effective, functional and uniquely innovational choice
when compared with a traditional vehicle alternative. Obviously, owning the versatile
REVolution would be pragmatic and at the same time economical since it would replace the
need of owning and/or leasing multiple types of vehicles. Implementation of any of these
methods allows for unprecedented flexibility in the range a single automobile can be used.
Imagine being able to have a sedan one day, a truck the next and a SUV or coupe the day after
that, all based on what your needs are for that day. With the REVolution Concept, that fantasy
can become a reality.

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Chapter 2
__________________________________________________________________
THE PROJECT STORY
______________________________________________________________________________
PROJECT KICK-OFF
The decision to conduct this project was made in September 2008 after we completed a previous
project to create a design concept for the next generation of Model T. The Model T design
concept development was a design competition created by the Ford Motor Company among
several universities. We had a group of about a dozen graduate students who worked for four
months to develop our Model T design. The experience was very satisfying and educational not
only to the students but also to the faculty. It gave the students the unique opportunity to work
in a team and understand and apply the systems engineering concepts and techniques into
creating a vehicle concept. They also developed a business plan to assemble and distribute the
vehicle through the dealer network. The Institute for Advanced Vehicle Systems (IAVS) wrote a
book to share the experience and technical content of that achievement. Therefore, we decided
to continue the process of designing a vehicle concept during the next summer. After a few
meetings, we decided that we should design an “electric vehicle” in the 2009 Summer Term.
To expedite the development and jump start the project, we decided to do some preliminary
work in understanding the electric vehicle issues by hiring two graduate students in September
2008. The students were asked to collect information on existing electric vehicles in areas such
as vehicle dimensions, weight, vehicle range, capabilities and characteristics of electric motors,
batteries, vehicle usage experiences, driver perception and needs, problems during vehicle
usage, etc. Later in the Fall term, a third graduate student joined the team to develop a quality
function deployment (QFD) chart for the electric vehicle. We had weekly meetings to review
progress and develop next steps to allow us to refine our thinking about the electric vehicle
issues.

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PROJECT DEFINITION
We wanted our electric vehicle to be not just an another electric vehicle but very innovative and
large that could easily carry four to five adults with their luggage—like a midsize vehicle that a
family could take on a long trip on a vacation (with a range of at least 200 miles without a
refueling stop). At the same time, we wanted the vehicle to be very economical and energy
efficient, especially, while using during weekday commutes (with a range of at least 60 miles
between recharging). As engineers, we wanted to develop the vehicle package to give students
the experience of creating the vehicle layout, understanding the interfaces between different
systems, understanding the problems of satisfying customers and people packaging, selecting
materials for various vehicle body and chassis components, understanding the safety issues in
handling high voltage lines, etc. We also wanted to make sure that the students could do the
necessary calculations to determine electrical powertrain by calculating motor size, weight,
torque, energy consumption, peak power needs, battery type, battery efficiency, battery weight,
battery volume, electrical controller design issues, etc. The vehicle was targeted for 2020 model
year. Thus, we expected the students to incorporate sophisticated driver information system
with interactive display screens to provide the driver information about the vehicle status, state
of charge, capability to input trip schedules, selecting most economical charging schedules,
compute vehicle usage costs, etc.
PRELIMINARY DELIVERABLES
The three graduate students who worked on the project during the Fall 2008 and Winter 2009
terms met weekly with the faculty advisor and produced the following: 1) a comprehensive list
of customer requirements, 2) a customer survey to understand vehicle features and functional
needs in terms of “Must have”, “nice to have” and “not needed”, 3) a QFD chart linking the
customer needs to functional requirements, 4) benchmarking data summary on electric vehicles,
5) selection of target vehicles (2010 Ford Fusion Hybrid, 2010 Toyota Prius, 2010 Honda Insight
and Chevy Volt), their specifications and technical information on their powertrains, and 6)
driver interface screens, menus and touch controls for driver-vehicle interface, vehicle-home
interface, and home-utility company interface.

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TEAM FORMATION AND ORIENTATION
In April 2009, we decided to select undergraduate students in engineering to work along with
our three graduate students during the Summer term. Six engineering students who had just
completed their freshman engineering year worked on the project. The team work formally
began on May 18th, 2009 and finished on August 31, 2009. Thus, we had only about 3.5 months
to develop the complete vehicle concept. The faculty advisor and the graduate students made a
number of short presentations on the work completed during the previous eight months and
held a number of brainstorming sessions.
TEAM WORK, CONCEPT GENERATION AND SITE VISITS
The team met three times a week and each meeting lasted four hours. During the first few
weeks we have a number of prepared presentations on the work done by the graduate students
and the faculty. Later time was spent in brainstorm and discussion sessions
After the first two weeks, we divided the team in two sub-teams and each sub-team was given
two weeks to come with preliminary design concept for their electric vehicles. During this time,
the students did extensive literature survey and discussed pros and cons on a number of
technical and design trends to select features for their design concepts. The ideas generated by
the two sub-teams were later pooled together to come up with the novel concept of splitting the
basic vehicle body into two parts. The first part essentially involved creation of a front module -
-from front bumper to the rear edge of the B-pillar section, and the rear module --from the rear
of the B-pillar section to the rear bumper. The two modules can be latched together to create a
vehicle. The commuter version of the car (110 inch overall length) will have a very short rear
module, essentially including the rear axle and a short cargo area that can be accessed by a
hatch door. For long trips, a different and longer rear module was created. This rear module
housed a rear seat for three passengers, a rear axle, luggage space, a generator driven by a
quasi-turbine or HCCI engine to extend the range in a traditional trunk design to create the
large sedan (189 inch overall length). Additional rear modules were also conceptually designed
to show that the entire vehicle could be reconfigured into a pick-up or an SUV version.
As the vehicle design was being refined, there were a number of questions such as a) Would a
reconfigurable vehicle be acceptable to the customers? b) Would the latching of the two
modules be technically achievable? c) What issues would be involved in creating electrical
connectors between the two modules?, etc. To find the answers and get reaction of the

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automotive industry experts, the students met with engineers from Chrysler, Ford and GM. The
Chrysler engineers allowed the students to drive their electric vehicles on their Chelsea proving
ground. The Ford engineers in Dearborn liked the latchable vehicle concept but felt that that
such a vehicle could not be engineered and introduced as a MY 2020 vehicle but a longer
development time with MY 2025 was a more appropriate target. The GM engineers helped the
students to realize the number of pins that need to be considered in designing the electrical
connectors and other aspects such as docking forces, weather-proofing, etc.
Many of the parents of our undergraduate students were excited to know about our vehicle
concept. Interestingly, the parents that worked in the automotive industry were more curious
and helped the students brainstorm on a number of issues. Several parents actually came to the
campus and met with the students to discuss a number of challenging problems and possible
solutions.
ANALYSES AND DESIGN WORK
The students developed full-size drawings of the vehicle on the wall and the floor of the
workroom and later created representation of the vehicle modules in Solidworks. The full-size
drawing helped visualizing the space available to package different mechanical systems,
components and occupants. The students estimated the target weight of the vehicle for the
commuter (2000 lbs) and the sedan (3700 lbs) versions and along with the required 0-60 mph in
8.5 sec acceleration capability. For more detailed design of different systems and modules, the
students worked in a number of sub-teams. The membership of the students to each of sub-
team evolved naturally depending upon the interests of the students.
The sub-teams involved: a) vehicle packaging, b) interior design involving components such as
e.g. instrument panel, driver interfaces and screens and seats, c) electrical system involving
creation and exercising of a model of electric vehicle for different urban and freeway driving
cycles, d) CAD representation of vehicle space frame, suspension system, location of electric
motors, battery, generator, quasi-turbine, etc. d) exterior design of the commuter and the sedan,
and e) business plan development.

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The specialized areas selected by the students to make their unique contributions were as
follows: Mark Bajor developed the implementation of the range extender involving a quasi-
turbine or a HCCI engine and photo-voltaic paint. Craig Cowing contributed in developing
displays for the instrument panel and some ideas of interior design. David Hnatio did all the
three dimensional CAD work in Solidworks and also exercised the Bunkspeed software to
create rendered pictures of the vehicles. Calvin McKinney developed module latching
configurations, electrical connectors and seat concepts. Justina Nagorka developed the overall
business plan for the vehicle and worked with the exterior design team. Sidharth Vallabhaneni
researched battery technologies and worked on interior systems. Aayush Gupta developed the
electrical models and exercised the models and designed the electrical powertrain system. He
also looked into required control systems and their functions, and future battery technologies.
Heramb Dandekar developed the driver interfaces for module latching/unlatching and vehicle
operation. He also created sketches of instrument panel and exterior concepts of various
reconfigurable options. Uday Sharma developed customer specifications, created QFD chart
and did the occupant packaging work. As the project progressed, Justina invited Trevor Greene
and Matthew Lisk who had just finished his Industrial Design program at the College for
Creative Studies (CCS) to help the team in developing good looking exterior designs for our
commuter and sedan vehicles. They did an outstanding job in creating the “skin” over the
vehicle space frame created by our students.
TRACKING THE PROGRESS AND QUESTIONING THE ACCEPTABILITY
OF THE CONCEPT
The entire team met on three days per week. During that time we discussed new ideas and
issues discovered or encountered by any of the team members and reviewed our progress and
decided on the next steps. Various sub-teams then scattered and worked on their issues
independently and discussed their progress and open issues in the following meeting.
The students always expressed concern if driving an electric vehicle would be as fun as driving
a vehicle powered by an internal combustion engine. We talked a lot about the artificially
generated sound to make the vehicle sound more like a “traditional” vehicle. We were also
concerned about the lack of sound from the electric vehicle which might not alert pedestrians
and other people close to the path of the vehicle. We talked about the electric shock hazards. We
talked a lot about how to latch and unlatch to swap different rear modules. Can an owner
perform the latching/unlatching task at home and in his garage or should he take the car to a
dealer? How about people who live in apartments and park their car in open lots? How would
they store their rear modules? Another idea surfaced was that the vehicle concept is more

10
suitable for people who want to rent different rear modules for different occasions. The
instructor always challenged the students by telling them “make sure that you will proud to
park the REVolution in your driveway.”
PROJECT PRESENTATIONS
Promptly on August 31, 2009—the last day our project, each team member incorporated his
PowerPoint slides into a master file and presented the vehicle design to the students and Roger
Shulze, our internal sponsor. This was the first time the entire team had made a series of
presentations without a chance for any rehearsal. It was a success and the next step was to
refine the presentation and make it to the entire engineering school in our Friday seminar on
September 18th, 2009. This was an occasion and we celebrated it just like when an automotive
company celebrates by introducing their new model to the press or in an auto show. We loved
it!
PREPARATION OF THIS BOOK
This book was prepared not just to document the many steps and the analyses performed, but
to give the readers an insight into how a handful of undergrad and grad students can work
together and create a new innovative vehicle concept in a matter of 3.5 months. We hope that
the tradition of summer vehicle concept design project continues on the UM-Dearborn campus
so that future engineering students, and possibly students from other disciplines can also join
and gain valuable experience “like our team”.

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Chapter 3
__________________________________________________________________
CUSTOMER AND FUNCTIONAL REQUIREMENTS
______________________________________________________________________________
CUSTOMER REQUIREMENTS
Customer requirements were very important for this project and they were determined through
a survey which was done on university campus itself. The results of the survey are:
a. A good looking vehicle at a reasonable price.
b. Must be a fun to drive vehicle
c. The electric vehicle must be energy efficient.
d. The electric vehicle should meet weekday (around 40-50 miles/day) and weekend (250-
300 miles/day) range requirements with one time charge.
e. The vehicle should take less time to fully recharge after a trip.
f. The electric vehicle should provide hassle free charging.
g. The vehicle must be designed such that it could be plugged-in for charging at any
location, at home, at work using a 220 VAC and a 110 VAC standard outlet. There
should be a dual voltage charging equipment in the car.
h. The electric vehicle should perform equally well on highways and with-in cities, with
various road conditions, weather conditions and grades. It should perform just like a
gasoline engine vehicles.
i. The vehicle must be safe in an event of a crash from any direction.
j. The vehicle must be capable of recharging and operation in temperatures ranging from 0
degrees to 120 degree Fahrenheit.
k. The vehicle must have comfort features such as sound, air- vents, heat, a/c-option,
power windows that are available in most current vehicles.
l. The vehicle should have a simple and easy to use informative human machine
interfaces.
m. The vehicle must have onboard diagnostic system for monitoring functioning of
different vehicle systems and subsystems and should provide warnings in case of any
malfunctions.
n. The vehicle should sound and feel like a current gasoline engine driven vehicle.
o. The two seater vehicle should have enough space for 2 adults and 4 Grocery Bags,
whereas the sedan should provide enough space for 5 adults and luggage for longer
trips and a golf bag.

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p. The vehicle should have usage warranty coverage and servicing support provided by
the manufacturer.
FUNCTIONAL REQUIREMENTS OF THE VEHICLE
Table 3-1 shows a relationship matrix between customer requirements and functional
requirements which would be cascaded to the system design later. Relationship is been
quantified using 1-3-9 methodology where 9 represents strong correlation, 3 shows moderate
correlation and 1 shows weak correlation.
Table 3-1 Functional Requirements

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Key functional requirements according to the relative weights are battery pack, electric motors,
vehicle packaging, and driver –vehicle interface. And for designing this concept vehicle the
team focused primarily on those three systems.
BENCHMARKED VEHICLES
Benchmarking existing hybrid electric vehicles (HEVs) and pure electric vehicles (EVs) was the
first task for this project. Several hybrid electric vehicles looked at were:
a) 2010 Ford Fusion Hybrid
b) 2010 Toyota Prius
c) 2010 Honda Insight
d) Chevy Volt (REEV: Range Extended Electric Vehicle)
Along with the HEVs, some of the EVs looked at were:
a) Tesla Roadster
b) Dodge EV
c) GEM Peapod
d) Phoenix SUV
e) I MiEV
f) Chrysler EV
A complete list of Benchmarked Vehicles along with their dimensions and specifications are
presented in Appendix 1.

14

15
Chapter 4
__________________________________________________________________
CONCEPT DESCRIPTION
______________________________________________________________________________
The requisite for augmented energy efficient vehicles has surged a number of innovative ideas
aimed at harnessing alternative sources of energy. As we set to develop the future generation of
automobiles that are environment friendly and efficient, we should consider an out of the box
approach that targets customer requirements.
The REVolution concept exemplifies how innovative concepts could be developed in the near
future. The concept is an amalgamation of calculated vehicle packaging, simulation and next
generation human machine interface. REVolution concept is based on range extended electric
vehicle concept, but viewpoint of the idea is built around benchmarked requirements projected
in future, which provide customers with exceptional flexibility and convenience.
REVolution has a capability to reconfigure in response to changes in customer needs and
requirements. The concept proposes a vehicle that can be operated as a two-seater city
commuter, which can be reconfigured into a mid size sedan by attaching an additional rear end
(rear module) as can be seen in Figure 4-1. The vehicle would be driven by electric motors in all
configurations. The front end (front module) of the vehicle will be powered by lithium-ion
batteries for a specific range whereas the rear end could be attached for long haul journeys.
Figure 4-1 Revolution Concept
The mid size sedan with rear end connected to the front would carry 4 to 5 adults with luggage.
So basically there would be three chunks with an option of buying or renting the third (bigger)
end as shown in Figure 4-2. The two units when attached would get power from a quasi-turbine

16
engine for extended range, which could also recharge the battery packs in the front end of the
vehicle. The charging of batteries would be through the standard 110 or 220 Volts at home or at
office. The swapping of rear end could be done at home, in a garage or even at a dealership. The
smart human machine interface would guide step by step and monitor the attaching and
detaching functions.
Figure 4-2 Vehicle Chunks (modules)
The revolution concept is designed to provide flexibility of different body styles like sedan,
pickup, SUV, by swapping different rear ends. It would be energy efficient, reduce noise
pollution and also provide an option of different powertrains in future.

17
Chapter 5
__________________________________________________________________
DESIGN PROCESS
______________________________________________________________________________
As an initial design process, the team was split into two sub-teams working independently to
explore different ideas and innovations. After a week, both teams presented their ideas and
thoughts. And then finally a Pugh chart was made to decide upon the winning ideas which
ultimately led to mix and match.
TEAM A CONCEPT (David, Justina and Mark)
This team had three team members. And some of their ideas and thoughts for their electric
vehicle were:
1. The overall vehicle design should be visually appealing.
2. Quality should apparent.
3. Photovoltaic paint: This would be capable of producing current when exposed to light.
This kind of paint is still in development stages.
4. Low window line and high window rake line
5. Wide overall stance
6. Tight wheel well gap and flush wheels to body
7. Tight fit between body panels
8. Quality interior trim
9. Quasiturbine based electric vehicle: The quasiturbine is basically based on 4 side rotary
engine design as shown in Figure 5-1. It is small, compact and is almost 8 times more
powerful than the conventional gasoline engine. It has a multi fuel capability which
gives an option of running it on water for short period of time. NOX emissions are also

18
less than the conventional engine. It has a limited rpm range that is between 700-1200
rpm but it is ideal when it’s been coupled to a generator.
Figure 5-1 Quasiturbine Engine
10. Gasoline or diesel engine driving a generator, but not tied into actual driveline
11. Performance exceeding gasoline engine standards.
12. Additional power for interior features can be generated with the use of photo-voltaic
paint coatings
13. Use of Ceramic Fiber Reinforced material which would be big weight saving and has a
long life time. An in years to come it is expected to get very cheap and would be ideal
for vehicle application.
14. Use of a polymer coated glass which prevents dispersion of light from condensed water
on it.
15. Transparent Engine cover as in Figure 5-2.
Figure 5-2 Transparent Engine Cover Figure 5-3 Diffuser and Flat Under Tray

19
16. Diffuser and a flat under-tray which would reduce the opposing aerodynamic lift force
as shown in Figure 5-3.
Some of the ideas proposed for vehicle interiors were;
1. Very few buttons and a clean looking
2. Use of quality materials
3. Center mounted LCD big enough so that it can be easily read and operated by the driver
without much distraction.
TEAM B CONCEPT (Craig, Sid, Mike and Calvin)
Some of the ideas presented by this team were:
1. Interchangeable battery packs: battery pack should be so designed and packaged in a
vehicle such that the discharged battery pack could be swapped by the charged battery
packs at the battery charging stations in future.
2. Solar power paint: This is cheaper and more efficient than the silicon solar cells. This
technology is in development stage but should be out for use by year 2020.
3. Regenerative Shock Absorbers: This would greatly help in improving the efficiency of
Hybrid electric vehicle by about 10 percent. Its working is fairly simple and can be
understood from Figure 5-4. Basically as the vehicle moves, the shock compresses and its
piston pumps the fluid. This compressed fluid uses its energy to drive a hydraulic motor
which is connected to an electric-motor generator. The power that’s produced could be
fed back to battery. This technology is currently in development stage and is expected to
be out in about 2 years.

20
Figure 5-4 Regenerative Shock
Absorbers
4. Compressed air engine as a secondary source to charge the battery. These engines are
fairly small and most importantly are emission free.
5. Harness heat energy: Since a big percentage of the losses in vehicles are from heat loss.
So if this heat energy is tapped, the efficiency of the hybrid electric vehicles or electric
vehicles could be further increased. Heat energy could be harnessed through a Stirling
engine or thermoelectric generators.
6. Collapsible Wind Mill: The idea here was to have a collapsible wind mill in hybrid
electric vehicles or electric vehicles which could be used to charge the batteries while the
vehicles were parked.
In similar lines, second option was to have hidden wind turbine which could be used
while braking to regenerate some of the energy. In other words use some of the
aerodynamic drag force to generate some electrical energy which could be used to
charge the batteries.
Both the ideas have some limitations to be considered here. Efficiency of windmill
typically is a function of its design. The bigger it is, the more efficient it becomes. So for
vehicle applications there would be big limitation on its size and design. Also hidden
turbine would be less efficient because of very small surface area.
7. Charge as you go infrastructure: This was the most innovative idea put on the table.
This was about having power strips which could be laid down on the roads in
congested/stop and go areas. This would resemble construction strips and would be
placed on top of road. And they could be easily installed and removed. So as car drives
over strips, its batteries could be charged through tires which would be embedded with
wire mesh which would be conducting electricity. Cities or state could pay for the strips,
and could tax citizens for their use. So essentially this would give cars an unlimited

21
range, provided you are driving in an area with power strips. And also thinking from a
economy standpoint, this would also contribute in creating jobs in all sectors.
8. Heads Up Display (HUD): This is not a new feature to cars, but an interactive one would
be. So basically it would be a reconfigurable HUD display. Through IR technology it
would provide the driver to manipulate what he wants to see, using just fingers and
hand motions.
Both the teams presented fairly interesting ideas and concepts for the entire team to think
about. Ideas presented were discussed and many of these ideas were incorporated in the
final design.

22

23
Chapter 6
__________________________________________________________________
VEHICLE DESIGN
______________________________________________________________________________
OVERVIEW
The specifications for two configurations which are city commuter and mid size sedan (as can
be seen from Figure 6-1) are following:
City Commuter Mid Size Sedan
Figure 6-1 City Commuter and Mid Size Sedan
Curb Weight:
• City commuter: 2000 lbs
• Sedan: 3700 lbs
Exterior:
• Length: 110 in / 189 in [Commuter/ Sedan]
• Width: 74 in
• Height: 55 in
• Wheelbase: 85 in / 107 in [Commuter/ Sedan]
Tire:
• Radius: 12 inch
Performance:

24
• Top Speed: 110 mph
• Acceleration (0 – 60 mph): 8.5 secs.
VEHICLE DESIGN
Keeping in mind the customer requirements, one of key objectives for the team was to come up
with an electric vehicle which would be stylish and good looking in any of the two
configurations. And at the same time, we also considered the aerodynamic aspect of the design.
Designing the vehicle for target Cd value was not in the scope of the project but several design
cues were taken from the benchmarked vehicles. And during the design process, vehicle design
changed every day. The following sketches and drawings are in order of successive iterations
that went through and ultimately leading to the final design.
Exterior Design
Initial exterior Sketches
Figure 6-2 First Sketch

25
Figure 6-3 Subsequent Vehicle Sketches

26
Commuter Car Exterior Designs
Figure 6-4 Commuter Car Designs

27
Sedan Exterior Designs
Figure 6-5 Sedan Designs

28
Alternate Body Styles
One of interesting possibility of this concept is, based on different rear units there would be
alternate body styles possible as shown in Figure 6-6. Challenge here for us was to design the
front unit which would compliment different rear units so the entire vehicle looks good.
Figure 6-6 Alternate Body Styles (Pick-up, SUV and a Raised Wagon)

29
Connecting Front to the Rear
As a very critical part for this concept was the design of electrical and mechanical connectors.
Several ideas were discussed as represented in Figure 6-7. Figure 6-7 (a) shows the section view
of the front end. And as can be seen, there would be 4 mechanical connectors on the 4 corners of
the frame and there would be an electrical connector in bottom. Two possible early sketches of
the cross-section of the vehicle with the connectors are shown in Figure 6-7 (a) and Figure 6-7
(b).
(a)
(b)

30
(c)
Figure 6-7 Approaches to Connect the Two Modules [(a), (b) showing the
cross sectional view of the connectors,(c) side view of the connector]
Figure 6-7 (c) shows the side view of the electrical connector. As can be seen, the male part is
been proposed to be of conical shape which would make the mating of the two connectors very
easy. No sophisticated sensors or actuators are required to align them together. The parts would
easily align themselves and would make a solid connection. The front module equipped with
front wheel drive can provide necessary maneuvering motions needed for undocking and
docking the modules.
Before the final design rendering, ALIAS design model was built as shown in Figure 6-8 by the
designers which was used to create the rendered designs.
(a)

31
(b)
Figure 6-8 Alias Model for the Final Vehicle Design
Clay Model-Sedan
Figure 6-9 shows the clay model representation for the design which was obtained from
Bunkspeed.
Figure 6-9 Clay Model Representation for the Sedan

32
Final rendered exterior design
Bunkspeed was used to create the rendered designs a shown in the Figure 6-10 on the
following two pages:
(a)

33
(b)
(c)
(d)
Figure 6-10 Final Rendered Vehicle Designs [Sedan in (a) and (b), Commuter in (c), and Sedan and
Commuter face-to-face in (d)]

34
Interior Designs
The team working on interior design benchmarked the interior designs of Chevy Volt, Chrysler
200 C and Lincoln C concept as shown in Figure 6-11, Figure 6-12 and Figure 6-13 respectively.
1. Chevy volt Interior Design
Figure 6-11 Chevy Volt Interior Design
Some of the design cues taken from Chevy Volt interior design (Figure 6-11) were:
• The buttons on the center-stack were eliminated by introducing a 10 inch touch
screen
• The Instrument Cluster was replaced by a Head-Up Display
• Storage space was provided in the center console for bags, purses etc.

35
2. Chrysler 200C concept-Interior design
Figure 6-12 Chrysler 200 C Concept Instrument Displays
Some of the Design cues from Figure 6-12 were:
• Combined Instrument cluster and center stack screen would increase the cost
• Steer by wire adopted
• Elimination of the shifter for P,R,N,D
3. Lincoln C Concept-Interior Design
Figure 6-13 Lincoln C Interior Design

36
Some of the design cues from this concept (Figure 6-13) were:
• The steer by wire technology identical to the Lincoln C concept was used.
• The instrument panel was kept as clean as possible.
• The high mount display was used for the warning lights.
• Screen scroll and select buttons were provided on the steering wheel for minimizing
effort.
Early Concepts of Interior Design
Sketch 1
This being a dashboard concept (Figure 6-14), it presents a few different items at once. First, the
center of the dashboard is the position of the speedometer, with the tacometer on the left and
the engine temperature to the right. Expanding from there to the far left could be the traditional
fuel gauge for the gasoline engine and to the far right lays the battery percentage or mileage
gauge. Faced with the choice for an electronic or LED screen, the driver can also customize the
position and layout of each feature and even add or subtract certain aspects deemed
undesirable.
Figure 6-14 Sketch 1 (Instrument Cluster)

37
Sketch 2
A concept sketch for the center of the steering wheel can be seen in Figure 6-15. Rather than
some of the more complex layouts found in some modern steering consoles, this is basically a
more contemporary steering wheel design. The scale and proportions of the different sections
could be easily altered to allow room for the airbag and other necessary electronics. The arms
that also serve as spokes have room for cruise control and have been left relatively blank as to
allow for latter layout of radio and voice command panels.
Figure 6-15 Sketch 2 (Steering Control)
Sketch 3
This is a basic layout of the center console (Figure 6-16). With simple shapes and a large screen
for GPS, radio and climate control, the screen itself could be left as a simple piece of dark
shaded glass when the vehicle is turned off, then comes alive once the system is switched on.
The vents at the bottom rather than at the top allows for air to flow to the second row more
easily through the center console rather than being deflected by the seats in the first row.
Figure 6-16 Sketch 3 (Center Stack)

38
Sketch 4
This is basically a top down view of the interior of the full sedan (Figure 6-17) which shows the
symmetrical layout of the seats. Being a vehicle that divides in half and reconnects to alternate
ends, it is necessary to make the front half comfortable enough for the first two occupants and
still allow enough space for the second row once connected to be comfortable as well.
Figure 6-17 Sketch 4 (Seating
Layout)
Sketches 5 & 6
These two sketches (Figure 6-18), show a concept for a lightweight seat. The reclining feature as
well as height and distance from front are still adjustable. The sketch shows manual adjust, but
motors for electric seats could also be featured. The proportions and dimensions can be adjusted
to an appropriate scale for ergonomics and weight if needed.
Figure 6-18 Sketch 5 and 6 (Seat Design)

39
Sketch 7
Sketch 7 (Figure 6-19), is a key fob design for electric vehicle. It would be having displays along
with some essential buttons. The driver could see the battery charge level from the key fob itself
from the house or office. Every time would come within certain range of vehicle, the
information would be updated itself and would be displayed for convenience.
Figure 6-19 Sketch 7 (Key Fob)
Early Instrument Cluster Layout
Important consideration here while designing was, to display what driver needs to see and
what he wants to see, with minimum clutter and in minimum glancing period. After many back
and forth designing, Figure 6-20 shows some of the early instrument cluster concepts proposed
by the team.
(a)

40
(b)
Figure 6-20 (a), (b) Instrument Cluster Concepts
Early Vehicle Interior Concepts
With the release date of the car set for 2020, the interior of the car has to be futuristic as well as
functional. Some of the innovative ideas that we have came up with are:
• Laser heads-up display
• Distorted heads up display to project a vertical screen on the horizontal windshield.
• Maps over-laid on the windshield for easy navigation
• Glass overlay on the entire dashboard and use laser projection to project climate control
and other control systems. Current systems that use this technology are laser projection
keyboards.
• Flip and fold seats to face forwards and backwards. Easier to converse with rear
passengers while parked.
• Use overlay for windshield to maps while driving and movies while parked.
With the above ideas as essential features for vehicle interiors, some initial sketches for the same
were drawn and can be seen in Figure 6-21 and Figure 6-22.

41
Figure 6-21 Initial Vehicle Interior Sketches

42
Figure 6-22 Initial Vehicle Interior Concepts

43
HUD Display
HUD is basically Head Up Display. It is a display superimposed on the windshield as shown in
Figure 6-23, where the necessary information is seen on the windshield for the driver without
requiring taking their eyes off the road. It was originally developed for Air-force for the fighter
pilots avoid looking down and in recent years there have been several applications and
advances with lasers in the HUDs.
Figure 6-23 Head Up Display
Advantages of HUD
1. Displays the information that otherwise could be gathered by looking on different dials.
Information could also be grouped in one place for better functionality.
2. Displays NAV, Bluetooth, and Gauges all in one place making it much more efficient.
3. Data is projected so that it won’t distract the driver’s attention.
4. Eyes refocus much faster when you switch from the road to the projected display that
usually floats 15 feet in front of you.
One of the challenges this technology is currently facing is the complicated optical system that
projects the data. The display should be as legible both in clear sun and in night. And to achieve
this, complex projectors and other optical systems are needed. Considering the pace with which
this technology is developing, it is fairly optimistic to assume that it would ready to use by 2020
for vehicle applications.

44
Final rendered interior layout
Final version of the interior design was rendered using Bunkspeed and can be seen in the
Figure 6-24.
Figure 6-24 Final Rendered Vehicle Interior Design

45
STRENGTHS/WEAKNESS OF THE “SPLIT” VEHICLE CONCEPT
This concept was really driving us forward and each day we found some new possibilities or
advantages of this concept. And at same time we also realized some of the key limitations or
issues that need to be resolved before any automotive company could really take this to the
production stage. In the Table 6-1 and Table 6-2, key strengths and weaknesses or issues are
listed.
Table 6-1 Strengths
Strengths Issues/Considerations/Comments
1 Flexibility/Different Body styles:
Sports/Sedan/SUV/Pick-up. Family of Vehicles
Use adaptive system software and interfaces. Can
rent/purchase a different rear unit.
2 Improved Energy Efficiency Can use most efficient configuration to
accomplish different trip purposes
3 Extended range with a choice powertrain Added batteries, Turbine/IC
4 Choice of drive configuration: Front/Rear/All wheel
drive
A lot of choices to satisfy different needs and
lifestyles at reasonable cost.
5 Repair or Replace only one end unit
6 Choice of front end units Car/Truck
7 Chassis and spaceframe Allows economical design and assembly
8 Improved space utilization Smaller space used for powertrain and batteries in
front unit
9 Purchase cost can be spread over customer lifestyle Can buy different units when needed
10 Easy changeover without a dealer/mechanic Design so that any driver can change without
help. Power latching/unlatching,
jacking/lowering, and movements during
docking/undocking.
11 Smart Driver Interface Driver interface recognizes rear unit capabilities
and allows controlling the entire unit with all
functions. Constantly available and updated
driver information system.
12 Flat floor-- no tunnel in the floor No propeller shaft, exhaust pipes, or fuel lines

46
Table 6-2 Weaknesses
Weaknesses Issues/Considerations/Comments
1 Changeover time Automated aligning and latching with driver
monitoring and override capability. Use solenoid
operated latching mechanisms
2 Added complexity and weight Additional structure; Powertrain complexity.
Electrical connectors need to be protected and
power switched off during latching/unlatching.
3 Water/Air/Sound Leakage/sealing Complex, quick and easy change
4 Higher cost front unit More complex controls and displays
5 Need storage space for rear unit All customers may not have sufficient garage
space. Can front and rear units be stored in
standard garage length space?
6 Customer acceptance of the concept Would people like it? Need to do extensive
market research in different customer segments.
7 Additional jacking and docking wheels Max speed limit with docking wheels.
Electrically operated power jack? Or,
compressed air?
8 Learning/Training Need additional training on how to dock/undock;
safety issues during changeovers
9 Use of electrical connectors only between two units Use electric brakes to eliminate hydraulic
couplings
10 More complex electrical control modules Coordination between front and rear units for
power, braking, maneuvers, lighting
11 Climate control capacity Bigger luxury rear unit may have an additional
climate control unit.

47
Chapter 7
__________________________________________________________________
VEHICLE PACKAGING
______________________________________________________________________________
Vehicle packaging was started with locating the key reference points and contours, general
locations of which can be seen in Figure 7-1.
Figure 7-1 Key Reference Points
Key reference points located were:

48
a) AHP (accelerator heel point)
b) SgRP (Seating reference point)
c) Seat track length (SAE J1516, J1517)
d) Steering Wheeel Center (H17 and L11 dimesions)
e) 95th Percebtile Eyellipses (SAE J941)
f) 99th Percentile Head Clerance Contour (SAE J1052)
In the course of the concept development phase, the vehicle design was modified and optimized
frequently and it was becoming increasingly detailed. Below are the steps that we followed
during vehicle package development.
1. Determining of the Dimensions:
The exterior dimensions of the benchmarked vehicle (MY 2010 Ford Fusion), were laid on the
floor with a masking tape as can be seen in Figure 7-2, to get a feel of the available packaging
space. Further, taking certain design cues from the benchmarked vehicles and exterior design
sketches were created and projected to a flat wall (see Figure 7-3). This exercise helped us in
getting a good understanding of the interior packaging space available.
Figure 7-2 Plan View of the 2010 Ford Fusion (The outer
rectangle shows overall length and width)

49
Figure 7-3 Section View of Small Compact Vehicle and the Large Rear
Unit. [The top line shows the overall height of 2010 Ford Fusion]
The next step was to determine the cowl point, deck point, and windshield inclination angle
and ground clearance in order to determine approximate interior package space.
2. Vehicle Concept:

50
The vehicle concept involved creation of the reconfigurable vehicle with two different units that
could be attached and detached, with the front unit as the prime unit. In order to develop the
front unit, the exterior dimensions of the front unit were marked with the masking tape on the
side wall. In the Figure 7-4, the top line represents the height of the benchmarked vehicle. The
vehicle outline represents the front unit of the reconfigurable vehicle.
Figure 7-4 Vehicle Concept
3. Seating Package of the Front Unit:
The interior package of the front unit was developed using the SAE standards J1517, J941, J1052,
J826 and J1100. The package architecture was developed from the ground up. Ground clearance
and underbody structure determined the interior height. The acceleration pedal hardware with
consideration for operational clearances was located relative to the toe board structure. The
driver's ball of foot and accelerator foot plane angle was established at the accelerator pedal as a
function of the desired chair height from SAE J1516. The driver selected seat position was set in
place to define requirements for seat track travel accommodation (SAE J1517). The SgRP (H-
point) was established at 95 percentile accommodation point on the seat track. In addition, the
95th percentile eyellipses (using SAE J941) and 99th percentile head position contours (using SAE
J1052) were drawn. The roof clearance was measured from the head clearance contours.

51
All stated dimensions were calculated based on the reference points stated above. The basic
driver package is presented in Figure 7-5.
Figure 7-5 Driver Packaging
4. Suspension Packaging:
The packaging of the suspension system involved packaging of components like springs, shock
absorbers and linkages that connects a vehicle body to its wheels. The dimensions of the
benchmarked suspension system were marked on the floor to get a feel for the space required to
package the suspension components (See Figure 7-6). Adequate space was left for the wheels
and the suspension linkages to turn, when the vehicle is steered left or right. The space between
the two front suspensions would be used to estimate packaging space for two motors and the
power electronics.

52
Figure 7-6 Suspension Packaging
5. Packaging of the Motors and Battery Pack:
The motors were packaged in the front unit of the reconfigurable vehicle, between the two front
suspension systems. The battery pack was positioned under the floor pan of the front unit. This
was done in order to provide quick swapping of the batteries from the bottom of the vehicle, so
that less time would be consumed in replacing the battery pack in the first unit of the vehicle.
Battery and motor dimensions were figured out based on power and energy requirements.
Dimensions of each can be seen from Figure 7-7 and Figure 7-8 respectively below.
Battery pack: 4.93 cubic feet
Dimensions: 4” x 53” x 40”
Figure 7-7 Li-ion Battery

53
Dimensions: D =14”, L = 12”
Figure 7-8 Electric Motors
6. Packaging of the Rear Unit:
The rear unit of the sedan required development of a seating package for the rear passengers,
space allocation for rear suspension system and the range extender Quasi-turbine system. The
components to be packaged in the rear unit were springs, shock absorbers, linkages, fuel tank,
quasi-turbine engine, generator, and power electronics. The quasi turbine engine in the rear
would get fuel from a fuel tank placed under the rear passenger seat. The engine and generator
located in the rear were positioned between the two rear suspension systems. Since the space
occupied by the Quasi-turbine engine is one eighth compared to normal gasoline engine, there
was sufficient space to be allocated for the packaging of the spare tire and luggage
compartment.
7. Packaging of Telescopic Jacks:
The telescopic jacks with small wheels, operated to reconnect or disconnect the two units of the
vehicle are packaged in the bottom side of the B pillar of the front unit. As the system is
activated, the telescopic arms supported by a worm gear mechanism are moved down. The base
of the mechanism checks the ground level and aligns itself parallel to it, to support disconnect
or reconnect activity.

54

55
Chapter 8
__________________________________________________________________
CAD OUTPUTS
______________________________________________________________________________
After the dimensions of vehicle (exterior and interior), motors and batteries were determined,
next step was of developing the CAD models for the concept. Software mostly used here was
SOLIDWORKS. Figure 8-1 shows the initial design and Figure 8-2 shows the subsequent design
with various subsystems.
Figure 8-1 Initial CAD Designs

56
Figure 8-2 CAD Designs
Front and the rear suspensions, motors and a cradle for placing the motors, wheels were
designed seperately using SOLIDWORKS. And then all the subsystem were brought together to
form the complete unit which was one of the toughest part. Finally, the finallized designs were
imported in the Bunkspeed for rendering. Figure 8-3 shows the SOLIDWORKS design for front
and rear suspension system along with the wheels.
(a)

57
(b)
(c)
(d)
Figure 8-3 (a) Solidworks Design for Front Suspension System, (b) Solidworks Design for Rear
Suspension, (c) Front unit with the Motors, (d) Rendered Design for Suspensions, Motors, Motor Cradle,
Wheels

58
Some of the CAD drawings for the vehicle (commuter version) are shown in Figure 8-4.
(a)
(b)
(c)
Figure 8-4 (a) Side View, (b) Rear View, (c) Angle View

59
COUPLINGS FOR LATCHING FRONT AND REAR UNITS OF THE
VEHICLE
A very vital part of this project was to design the connectors capable to hold the front and rear
units together in all situtations and would also allow automatic latching and delatching. The
design proposed by the team is shown in Figure 8-5. Both, individual components and the
complete assembly for the connectors can be seen from the figure. As a part of the future work
on this project, a FEA analysis of such a design needs to be conducted.
Figure 8-5 Mechianical Connectors (Four connectors will be used to latch front unit to the rear unit of the
vehicle)

60

61
Chapter 9
__________________________________________________________________
CHASSIS /BODY
______________________________________________________________________________
Figure 9-1 shows the chassis design. It would be aluminum break form chassis that would split
in two parts and would allow quick change of rear section while the front part would be
common to both the commuter and the sedan versions. This sort of design was selected because
it would have minimal tooling cost and most importantly would be extremely light weight.
Figure 9-1 Chassis
The basic differences in the chassis for the two styles of vehicle can be better understood
from Figure 9-2. The top section in Figure 9-2 shows the chassis for the small city commuter
and the bottom section shows the chassis for the sedan.

62
Figure 9-2 Chassis Design for Two Styles of Vehicles
Figure 9-3 Chassis Components
Chassis was designed to have minimum number of components to reduce the assembly
time and tooling costs. Figure 9-3 shows the exploded view of chassis with several chassis
components.
Another important feature of this chassis specific to this concept was that it would house the
battery pack under the floor pan. The battery pack placed within the front section could be
installed or removed by sliding in and out under the knotched side rails as shown in
Figure 8-4. This would make battery servicing or battery replacement fairly easy.

63
Figure 9-4 Battery Sliding In-Out Feature of the Chassis
Chassis was then put over the wheels and suspension sub-assemblies. Many modifications
to the design were made to assure that every component/subsystem was dimensionally and
functionally compatible to each other. Chassis on wheels is shown in Figure 9-5.
Figure 9-5 Chassis on Wheels
The next step was to incorporate the interiors such as seats, dash, and steering wheel inside
the chassis as can be seen from Figure 9-6. The actual vehicle assembly sequence would be

64
different from the sequence of figures presented above because there are several other
systems and subsystems to be considered here.
Figure 9-6 Chassis with Interiors
FINAL PACKAGING
Considering all essential subsystems and their specifications, the final CATIA model of the
sedan version of the vehicle is shown in Figure 9-7.
Figure 9-7 CATIA Model
The developed CATIA model was later imported to the Bunkspeed software to create a
rendered model as shown in Figure 9-8.

65
(a)
(b)
Figure 9-8 Final Rendered Model
The model includes complete interior package, powertrain package, suspensions, and wheel
wells.

66

67
Chapter 10
__________________________________________________________________
EV POWERTRAIN DESIGN
______________________________________________________________________________
SPECIFICATIONS
Motors
Two motors, each driving a front wheel
Type: PMSM (Permanent Magnet Synchronous Motor)
Power Output: 107 KW
Torque: 496 NM
Voltage: 350 V
Battery
Type: Li-ion
Energy: 42 KWh (all auxiliary loads on for entire trip)
Weight: 419 kg
Volume: 4.93 cu. Ft.
Range: 60 miles (in a single charge; 70% city and 30% highway)
Generator
Power Output: 28 KW

68
Engine
Type: Roller Carriage Quasi-turbine
Displacement: 1.0 L
Ignition: Photo Detonation
Fuel: Gasoline- 87 Octane
Power Output (H.P.): 250 @ 3000 RPM
Torque: 300 lb-ft @ 1800 RPM
Fuel Tank
9 gallons (Range: 350 miles; 20% city and 80% highway)
SYSTEM CONFIGURATION
The objective for designing the electric vehicle powertrain architecture was to meet the
customer’s range and efficiency expectations. Now, considering a BEV (i.e battery based electric
vehicle), it is obvious that bigger the batteries, better is the range. But there are also several
limitations to the battery size that can be put in the vehicle. Weight and volume required have
the biggest influence in the decision of choosing the right battery size. With our concept, this
was made a bit easy. As here the battery provides power to pull the vehicle for the first 60 miles
and any effort made to drive the vehicle further, would be provided by the quasi-turbine
generator. So basically depending upon the miles driven, vehicle energy system can be
categorized in two cases as following:
1. Mileage < 60 miles
The front unit would be pure electric vehicle powered by battery. Energy flow in this case
can be seen in the Figure 10-1.

69
Figure 10-1 System Configuration for Travel Less than 60 Miles
In the Figure 10-1, B refers to the battery system, P refers to power electronics with motor
controllers and digital signal processors as most important components here, M refers to the
electric motors. In this configuration, energy path is from batteries to motors through power
electronics.
2. Mileage > 60 (Range Extender)
With travel distance exceeding the 60 mile range, the quasi-turbine engine and generator
kicks in to supply the power needed for traction. Energy flow in this case can be seen in the
Figure 10-2.
Figure 10-2 System Configuration for Travel Greater than 60 Miles
In the Figure 10-2 , FT refers to fuel tank, E refers to engine, G refers to generator, P refers to
power electroncis, B refers to battery system , M refers to motors. Here the path of energy

70
flow is fron engine to generator to motor through power electronics. And it would be the job
of controllers to run the motors and the engine at appropriate speeds so that driver torque
demands are met and at the same time overall system efficiency is maximum.
3. Regenerative Braking
In either of case, while braking electric motors would be regenerating power and that would
be used to charge the battery. Energy flow in this case can be seen in the Figure 10-3.
Figure 10-3 Energy Flow while Regenerating

71
ELECTRIC VEHICLE POWERTRAIN PARAMETRIC MODEL BASED
ANALYSIS
A parametric model was used to analyze different powertrain configurations for the concept.
The model description is presented in Appendix 2. The vehicle configuration used for the
powertrain design analysis in shown in Figure 10-4.
(a) (b)
Figure 10-4 Concept Representation
The electrical components mounted in the front and rear units and shown in Figure 15-4 are
denoted by using the following terminology:
F (Front) = Front unit
R (Rear) = Rear unit (for sedan)
M1= Motors in the front
B1=Batteries in the front
M2 = Motors in the rear part
B2 = batteries in the rear part
IC2= Internal combustion engine (range extender) in the rear
G2= Generator in the rear
F2= fuel tank in the rear part
Figure 10-4 (a) is a simple representation of the front unit (F) of the vehicle with a small back
end. It would be a battery based electric vehicle and would be comprising of electric motors
F
M1, B1
R
M2, B2,
IC2, G2,

72
responsible for providing traction in any configuration. Thus, the front unit includes motor
(M1) and battery (B1). As shown in Figure 10-4 (b), a bigger rear unit (R) can be latched on to
front unit basically for a longer trip or for some family trips with more than two passengers.
This sedan reconfiguration really gave us an opportunity to explore different sources of energy
such as battery (B2), generator (G2) and engine (IC2). Also for traction purposes, possibility of 4
wheel drive could be provided by incorporating two additional motors (M2) in the rear end. In
addition, it would require costly and complex controllers for operation of M2 with M1. These
options were all considered in the analysis for choosing the right combination.
For the analysis, vehicle dimensions were fed in the parametric model to obtain various
outputs. Both the vehicle configurations were analyzed for different powertrain options and for
different load conditions. Table 10-1 shows different configuration used to analyze the
feasibility of the different power-train options for the concept. Refer to Appendix 2 for
equations programmed in the model used for the analysis. Two vehicle configurations were
analyzed and they are 1) F: just front unit with small back end, 2) F+R: Front unit with bigger
rear end. With these vehicle configurations, a total of 17 powertrain combinations were
analyzed as can be seen from Table 10-1. The model was run for various loads varying from just
the driver only to fully loaded (i.e driver plus passengers plus cargo of 150 lbs). The results
shown in Table 10-1 are for fully loaded condition and these output numbers were used for
designing the powertrain.
The outputs of the analysis shown in Table 10-1 include: motor power (KW), motor torque
(Nm), battery volume (cu. ft.), battery weight (kg), battery capacity (Ah), battery energy (KWh).
Also generator power (KW) could be determined from the model based on the set generator
efficiency. Generator here would be basically an electric motor that is around 80 percent energy
efficient. And though quasi-turbine engines are much more efficient than conventional engines,
their energy efficiency was assumed to be 42 percent (which is the worst case). So the average
engine–generator efficiency fed in here was 56 percent. These configurations and combinations
were analyzed for the following four usages: 1) 60 miles with 100 percent urban driving, 2) 60
miles with 70 percent urban driving and 30 percent highway driving, 3) 200 miles with 30
percent urban driving and 70 percent highway driving, 4) 350 miles with 30 percent urban
driving and 70 percent highway driving. For extended range of 200 or 350 miles, driving style
with 100 percent urban and 0 percent freeway is not considered in the analysis as customers
with this driving style are assumed to be fairly less. Urban and highway trip profiles considered
here would be discussed on the next section.

73
The above evaluations also included additional auxiliary electrical loads from systems such as
climate control, vehicle lighting system, entertainment system, etc.
Table 10-1 Model Analysis Results
(a)
(b)

74
(c)
(d)
Powertrain choice was made on the basis of running cost, battery weight and battery volume.
Just as an example, if we look at Table 10-1 (b), for F+R vehicle configuration and for usage 350
miles, battery alone would weigh around 2700 kg which is not at all feasible. So that was one of
primary reasons we went for range extended kind of architecture. Also having two motors in
the rear unit, looked interesting to us before, but then we realized it would increase the system
complexity a lot and plus would add extra weight and cost to the overall system.
So what we concluded was that having two motors in the front unit and a generator and engine
in the rear unit for range extension would be most efficient, simple and realistic configuration
for this concept.

75
DRIVING CYCLE
The vehicle is been designed for first 60 miles all electric and then the rest is been driven by the
range extender. And breaking those miles further, the power-train is been designed for:
60 miles: 70% UDDS cycle and 30% highway
350 miles: 20% UDDS cycle and 80% highway
Figure 10-5 shows the EPA urban driving cycle and Figure 10-6 shows the EPA highway
driving cycles that were used for calculations.
Figure 10-5 EPA Uraban Driving Cycle
Figure 10-6 EPA Highway Driving Cycle

76
ASSUMPTIONS
Like any other analysis, this analysis was done based on several assumptions and it’s important
to realize that the results totally depend on these assumptions. The assumptions taken were:
Dynamics
1. Cd : 0.29
2. Max. rolling resistance at standstill : 0.009
3. Rolling Resistance Coefficient (s2/m2) : 1.70E-06
4. Density of air (kg/m3): 1.18
Li ion Battery
1. Specific energy density (Wh/kg): 100
2. Specific power density (w/kg): 320
3. Volumetric energy density (Wh/l): 300
4. Efficiency for Drive line: 90 %
5. SOC range: 30-70
6. Bus voltage: 350 V
Auxiliary Loads
1. Energy consumed for Urban cycle (KWh/cycle): 1.079
2. Energy consumed for Highway cycle (KWh/cycle): 0.638
[For battery capacity the auxiliary loads are assumed to be all on for entire 60 miles trip]
Charging
1. Charging rate (amps): 10 (minimum)
2. Charging cost (c/KWh): 11 (avg. DTE charging cost excluding the road tax)

77
MOTOR DESIGN
From the maximum torque requirement calculated using the parametric model, required motor
base speed is:
Motor Speed: 4122 rpm = 68.7 rev/sec
For designing a motor, variables such as air gap flux density and electric loading are needed.
They are function of motor power keeping other factors constant. And for a certain material
assumed, their values obtained are:
1. Max. Power: 82.44 KW
2. Air gap flux density= 0.7 [Based on assumptions]
3. Electric loading= 24 [Based on assumptions]
As can be noted max power taken here was 82.44 KW as this was the maximum power
considered in the existing look up table. Motor design for actual motor used in the vehicle
would be approximated from here.
Power (W) / speed (rev/sec) = 1200
Co = (pi2*air gap flux density * Electric loading)
= 165.64
D2l= Max. Power (KW)/ (Co * speed (rev/sec))
= 0.007245 m3
= 442.09 cu. inch
Approximation
Just an approximation, motor would be designed considering the actual motor power to
maximum power from before (82.44 KW) factor.

78
1. For motor of power 125 KW,
Factor= 1.516
D2l (125 KW) = 670.3221159 cu. inch
Volume (125 KW) = 526.2028609 cu. inch
= 0.304515545 cu. ft.
2. For motor of power 215 KW,
Factor= 2.6079
D2l (215 KW) = 1152.954039 cu. inch
Volume (215 KW) = 905.0689208 cu. inch
= 0.523766737 cu. ft.
Using the above values for D2l appropriate values for stator/rotor diameter and length can be
calculated.
3. For our vehicle, two 108 KW are chosen
Factor= 1.31
D2l (108 KW) = 579.1583081 cu. inch
Volume (108 KW) = 454.87 cu. inch
= 0.263234954 cu. ft.
Assuming a factor of 2 taking into consideration motor casing, wiring and the several
assumptions in the calculations, the volume is:
Volume= 909.74 cu. inch
Taking Length = 10 inch
Diameter = 11 inch

79
For packaging the complete unit, it becomes important to consider volume required for power
electronics. Calculating the exact volume for power electronics was out of the scope of this
project. So to factor in that, we visited few dealers and saw some of the hybrid electric vehicles.
And based upon our estimates, at least a factor of 2 should be further assumed.
So, volume = 1819.48 cu. inch
Taking length =12 inch
Diameter= 14 inch
And this was finally taken for motor unit packaging.
CHARGING TIME
With voltage = 220 V and current = 20 A, it would take about 9.5 hours to charge a completely
discharged 42 KWh battery.
We do realize that the charging time seems more than the current plug in hybrid electric
vehicles or electric vehicles. But charging time is basically a function of battery capacity and in
our case battery capacity is more as its been designed for more electric range and is also capable
to handle extreme real time situations and load.
SOC ANALYSIS
Present battery specifications are so far based on SOC range 30 –70 %. With the improvement in
the battery technology it is certain that more charge could be drained from them. It may be
possible to that minimum discharge level could be as low as 20 % and maximum could be as
high as 80 %. And if it is possible, required battery energy, battery weight, battery volume
changes entirely. So to see the effect of change of SOC range on battery weight, volume and
energy, an analysis was done for the chosen concept vehicle. Table 10-2 shows the results of the
analysis.

80
Table 10-2 SOC Analysis Results
Available (%) Battery Weight Battery Volume Battery Capacity Energy required
1 30-70 40 419.23 4.93 119.78 41.92
2 25-70 45 372.65 4.38 106.47 37.26
3 25-75 50 335.38 3.94 95.82 33.54
4 25-80 55 304.89 3.59 87.11 30.49
5 25-85 60 279.48 3.29 79.85 27.95
SOC Range Analysis
The effect could be better seen from Figure 10-7 a), b), c). A very obvious conclusion from the
graphs are that the required energy and hence the battery weight and battery volume drops a
lot, as the available SOC range increases.
(a)
(b)

81
c)
Figure 10-7 a) Effect of SOC Change on Battery Weight, b) Effect of SOC Change on
Battery Volume, c) Effect of SOC Change on Required Battery Energy
Another very interesting analysis done here was by keeping the battery energy the same as
before and increasing the possible SOC range. Table 10-3 shows the analysis. Vehicle range is
been affected directly and it can be inferred that the vehicle range increase to about 111 miles
pure electric.
Table 10-3 Effect of Available SOC Range on Electric Range
SOC Range Available (%) Battery Volume Volume Difference Equivalent energy TotalRange (60+Extra Range)
1 30-70 40 4.93 0 0 60
2 25-70 45 4.38 0.55 4.67228025 77.25233143
3 25-75 50 3.94 0.99 8.41010445 91.05419657
4 25-80 55 3.59 1.34 11.3833737 102.0329529
5 25-85 60 3.29 1.64 13.9318902 111.4433155
42.03295293
51.44331552
Extra Range!!!!
0
17.25233143
31.05419657
Figure 10-8 graphically shows the affect of possible SOC range on the vehicle range.

82
Figure 10-8 Effect of SOC on Vehicle Range
CONNECTOR AMPS
Generator power =28KW
Bus voltage = 350 V
Current through connector = 80 A
So, to transfer the current from rear part of the car to the front through the connectors, thick
wires would be needed for carrying about 80A.
There would be two types of connectors needed to assure connectivity between the front and
rear units of our reconfigurable electric vehicle. One would be the power connector transmitting
electrical power generated by the power unit mounted in the rear unit to power the batteries
located in the front unit. These connectors would be capable of transmitting about 80 amps at a
bus voltage of 350 Volts. Other multi-circuit connector will be used to connect all body electrical
circuits (e.g. rear lighting, window and lock controls). Some examples of multi-circuit
connectors provided by our industry mentor (GM) are shown in Figure 10-9.

83
Figure 10-9 Multi Circuit Connectors

84
POWERTRAIN ALTERNATIVES FOR ELECTRIC VEHICLE RANGE
EXTENSION
Recent automotive R&D has focused on transforming today’s gas guzzling society into a
greener, electric future. Based on research, customers commute on average 40-60 miles/day, and
require a range of about 300 miles. These numbers have been easily achieved with the gasoline
engine, but electric vehicles struggles. This is where a range extender comes into play. For the
purposes of the 2009 UMD Electric Vehicle team, the Quasiturbine has been chosen for the
primary range extender; however HCCI and diesel have been selected as alternative range
extending technologies.
As promising as the Quasitrubine may seem, the technology is still in its infancy. So in case the
Quasiturbine technology fails, alternative technology would be Homogeneous Charge
Compression Ignition, or HCCI. This technology, which is set to debut in early 2010, would
most likely be proven a reliable powerplant for vehicles use by 2020. The engine itself isn’t
much different than the conventional gasoline engine of today. There are still pistons, valves,
and complex control systems. The difference lies within the combustion chamber as can be seen
from Figure 10-10. Normal Spark ignition engines today are only 19-24% efficient. Some fuel is
left unburned or partially combusted, resulting in reduced efficiency, increased emissions and
lower performance. Diesel engines have solved the inherent combustion flaws of the gas engine
by introducing the use to direct injection and compression ignition. Though a great process,
there are still flaws such as increased engine vibration, noise and various emissions from
unburned diesel fuel. So what about combining the characteristics of a gasoline and diesel
powered engine? The result is HCCI, the diesel like engine which runs on gasoline.
Figure 10-10 Engine Combustion Comparison

85
For the purposes of our Electric vehicle, a 160 HP three cylinder HCCI engine would be an
ample backup powertrain. The engine is purposefully built for the power generation task, and
since HCCI works best at a non-variable RPM range, such as 1800 RPM, it is no wonder GM has
decided to use this engine technology for power generation. The use of HCCI increases fuel
efficiency by 15%.

86

87
Chapter 11
__________________________________________________________________
CONTROL SYSTEMS AND THEIR FUNCTIONS
______________________________________________________________________________
Some of the controls systems that would be present in the vehicle are:
1. Battery Management Systems: Fast acting Energy Management System which must
interface with other on board systems such as engine management, climate controls
communications and safety systems.
Objectives
a) Protect the cells or the battery from damage
b) Prolong the life of the battery
c) Maintain the battery in a state in which it can fulfill the functional requirements of
the application for which it was specified.
Functions:
a) Cell Protection: Monitor and protect batteries from out of tolerance operating
conditions.
b) Charge Control: Optimize battery charging.
c) SOC Determination: For providing the user with an indication of the capacity left in
the battery and for control circuit to ensure optimum control of the charging process.
d) SOH (State of Health) Determination:
e) Cell Balancing: In multi-cell battery chains small differences between cells due to
production tolerances or operating conditions tend to be magnified with each charge
/ discharge cycle. Weaker cells become overstressed during charging causing them to
become even weaker, until they eventually fail causing premature failure of the
battery. Cell balancing is a way of compensating for weaker cells by equalizing the
charge on all the cells in the chain and thus extending battery life.
f) Communications: Communications between the battery and the charger or test
equipment. Some have links to other systems interfacing with the battery for
monitoring its condition or its history

88
g) Providing a failsafe mechanism in case of uncontrolled conditions, abuse or loss of
communications.
h) Isolating battery in case of emergency.
i) Setting the battery operating point to allow regenerative braking charges to be
absorbed without overcharging the battery.
j) Predicting the range possible with the remaining charge in the battery.
k) Providing means of access for charging individual cells.
l) Responding to changes in the vehicle operating mode.
m) Recording battery usage and abuse.
Main building blocks for BMS are:
i. Battery Monitoring Unit: Microprocessor based unit.
ii. Battery Control Unit: Contains all the BMS power electronics circuitry. It takes
control signals from the Battery Monitoring Unit to control the battery charging
process and to switch the power connections to individual cells.
Functions:
a) Controlling the voltage and current profile of the charger output during the
charging process.
b) Providing top up charge to individual cells to equalise the charge on all cells in
the battery chain.
c) Isolating the battery during fault or alarm conditions
d) Switching the regenerative braking charge into the battery as required
e) Dumping excessive regenerative braking charges when the battery is fully
charged
f) Responding to changes in the vehicle operating mode
iii. CAN bus vehicle communication network: popular bus for the automotive industry,
with in-vehicle communications. High-speed CAN reaches 1Mbps and is used for
engine control and power-train applications. Low-speed/fault-tolerant CAN reaches
125Kbps and is used for body and comfort devices
2. Engine Control Unit (ECU):
a) Measures the operation conditions of engine.
b) Evaluate sensor inputs and provide appropriated output to the actuators.
c) Minimize emissions and fuel consumption by making engine run sweet spot at fuel
map.
d) Provide system diagnosis in a malfunction situation.

89
3. Transmission Control Unit (TCU):
a) Shift point control
b) Engine torque control during shifting
c) Related safety functions
d) Diagnostics functions
e) Adaption to driver’s behavior and traffic situation
f) Communications with other ECUs
4. Cruise Control Systems:
a) Sustain steady speed under varying road conditions.
b) Increase fuel efficiency.
c) Failsafe mode of operation.
5. Braking Control (ABS);
a) Minimize stopping distance: maintain maximum frictional forces on all wheels in all
road conditions.
b) Stability: Control the yaw movement by maintain by keeping wheels near peak
frictional force. (max. force in split coefficient surface can cause yaw movement)
c) Steerability: maintain high lateral force, possibility of steering around the obstacle
through good peak friction force range control.
6. Traction Control Systems (TCS):
a) Prevent the wheels from spinning in response to excess throttle.
b) Optimize stability/steering control-engine torque control and supplementary braking
intervention.
c) Optimize traction.
d) Monitor wheel speed and acceleration rate.
7. Suspension Control Systems:
a) Improve ride comfort and stability (basic function)
Shock absorber control system
a) Select optimum damping force for various driving conditions.

90
b) Control vehicle movement against inertial forces such as roll (when the vehicle
turns) and pitch (when the vehicle brakes).
c) Prevent vehicle vibration caused by the vehicle inputs.
d) Optimum damping forces for various running conditions.
Electronic Leveling Control System
a) Maintain low spring rate to achieve good ride comfort independent of road
conditions.
b) Increase vehicle height on rough road surfaces.
c) Change damping forces and spring rate in accordance with the driving
conditions and road surfaces.
Active Suspension System
a) Control the force generated from the continuously supplied energy.
b) Generate forces function of sensors input

91
Chapter 12
__________________________________________________________________
ELECTRICAL/ELECTROMECHANICAL SYSTEMS
______________________________________________________________________________
Some of the electromechanical systems and their functions:
1. Steering Control System:
a) Improve steering feel, power steering effectiveness, and hence increase the steering
performance.
b) Reduce steering effort at low speeds
c) Supply feedback for appropriate steering reaction force at high speeds
d) Maintain manual steering function in an event of malfunctioning.
2. Climate Control System:
a) It’s basically an automatic climate control system for comfort of driver and
passengers.
b) Compute the most effective heat and ac flow rates
3. Lighting and Wipers:
Controlling lamps with power electronics have many advantages such as:
a) Easy diagnostics compared to mechanical switch and relays.
b) Integrity of the lamps can be easily tested.
c) Besides turning light on and off, light intensity can also be varied.
d) Detect abnormal conditions such as open or short circuited lamps.
Windshield Wiper control allows:
a) Variable speed operation
b) Provide sufficient torque to run the wiper mechanism under worst case conditions.
c) Activate the motor with appropriate time interval.

92
4. Multiplex Wiring system:
Three types of vehicle data communication network:
Class A: Vehicle wiring is reduced by transmission and reception of multiple signals
between different nodes over the same signal bus.
Class B: Data is transferred between nodes to eliminate redundant elements such as
sensors.
Class C: High data rate signals associated with real time control systems (eg. Engine
controls) are set over signal bus to facilitate distributed control and to reduce wiring.
Several advantages are:
a) Reduces vehicle system cost
b) Reductions in number of circuits and wires needed
c) Support built in diagnostics for manufacturing and service
d) Ease of assembly
e) Reduction in weight
5. Collision Warning and Object Detection:
a) Alert driver of potential hazard and assist him in taking suitable action as per the
situation.
b) Thus enhance safety.
These systems can be classified into two categories:
1. Passive systems: Detect and alert driver of hazards and risks
2. Active systems: detect hazards and then of possible also take suitable preventive
action to avoid collision.
Both require object detection.
Besides these systems there would be some special systems needed for this concept. Some of the
possible advanced systems are:
1. Unlatching control system:
Some of functions of these systems would be:
a. Check if telescopic jacks are in position.
b. Voltage /current cutoff.
c. Actuate mechanical breaking for the rear part.
d. Activate the unlatching actuators.

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