reference guide 2011

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Reference

GuideRelease 1

Written by: Matt Clifford, Purdue University

Anthony J. Palumbo, Bowling Green State University

Steven Dunlop, Purdue University


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We wish to acknowledge others that have contributed to the writing of this book. Without

their assistance the quality of this document would not be as complete.

Jeff Major Chief Engineer Electric Vehicle Institute, Bowling Green State University

Aaron Bloomfield Faculty, M.S.E.E., Northwest State Community College, Archbold, Ohio

Peter ORegan Grad student Purdue University

Mark Suchomel Grad Student Purdue University

Daniel White Director of Motorsports at Purdue, Purdue University

Garrett Hunter Western Illinios University

Grant Chapman Student Purdue University

Copyright reserved

Content intended to be used by registered evGrand Prix Participants

No other use with out prior written permission

Published by Collegiate Grand Prix Consortium,

First Edition March 2012


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ABSTRACT

The purpose of this handbook is to provide a guide for fielding a team, building a kart andcompeting in the evGrandPrix on track events. Topics include but are not limited to, organizing a

team, planning, designing, fabricating and building the racer, preparing for the race, and race dayinformation. By following this handbook teams should be better able to prepare their entry intothe evGrandPrix. The information presented in this handbook is not to be interpreted as the finalword of rules and specifications. These are provided in separate documentation. The informationpresented in this guide is a resource guideline, not as law. Teams are encouraged to be innovativeand think of new ideas as long as the rules and specifications are met.


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TABLE OF CONTENTS

ABSTRACT ......................................................3

FIGURES AND IMAGES ....................................6BACKGROUND ...............................................7

EV GRAND PRIX HISTORY ...............................8

CHAPTER 1 TEAM ...........................................9

Assembling a team ..................................... 9

Team Roles ................................................. 9

GENERAL TEAM ADMINISTRATION....................... 11

Travel Expenses ........................................ 11

Tools ......................................................... 11

Racer Costs ............................................... 11Registration .............................................. 12

Team apparel ........................................... 13

Team Log Book ......................................... 13

SPONSORS AND MARKETING .............................. 14

Sponsors ................................................... 14

Promotion expences ................................. 15

FINDING WORK SPACE ....................................... 15

Place to Work on Racer ............................ 15

Place to Research and Plan ...................... 15

Place to Practice and Tune Racer ............. 15

SCHEDULE/TIMELINE......................................... 16

CHAPTER 2 MECHANICAL ............................. 17

Chassis ...................................................... 17

Frame ....................................................... 18

Vehicle Measurements ............................. 19

Frame construction standards. ................ 22

Front Bumper ........................................... 23

Nerf Bars .................................................. 24Weight Analysis ........................................ 24

Fasteners .................................................. 24

CHAPTER 3 DRIVER RESTRATING SYSTEM ... 25

Seat and Seat Mounts .............................. 25

Driver Restraint system ............................ 25

Seat Belts, Harness and arm Restraints ... 26

Seat Belt Mount ....................................... 27Arm Restraints ......................................... 27

Seat Belt Mount ....................................... 27

Head Rest ................................................. 28

CHAPTER 4 BEARING, AXLES, STEERING ........ 29

Steering Assembly .................................... 29

Chassis tuning .......................................... 31

CHAPTER 5 BRAKING SYSTEMS ..................... 35

Brakes ...................................................... 35

Throttle .................................................... 35

Throttle and Brake Pedals ........................ 35

Brake Master Cylinder ............................. 36

Brake Caliper and Disc ............................. 36

Tires, Rims, Hubs, and Wheels ................ 37

Axle .......................................................... 40

CHAPTER 6 MECHANICAL DRIVE TRAIN ......... 41

Open Drive (Chain) Guard ........................ 41

Motor Mount Bracket .............................. 41

Motor Mount ........................................... 42

CHAPTER 7 ELECTRICAL SYSTEMS.................. 43

TRACTION POWER SYSTEM ................................ 43

CHAPTER 8 BATTERY ................................. 44

Battery Selection ...................................... 44

Battery Chemistry .................................... 44

Pack Voltage ............................................ 45

Capacity rating ......................................... 45

Batteries ................................................... 48

Packs ........................................................ 48

Charging ................................................... 50

Battery Box .............................................. 50Battery Mount ......................................... 51

Storage ..................................................... 51

Battery Temperature Control ................... 52

Battery Safety .......................................... 53

Charging and discharging ........................ 53


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Emergency Procedures ............................. 55

CHAPTER 9 BATTERY MANAGEMENT SYSTEMS

(BMS) .......................................................... 57

BMS Configurations ................................. 58

Distributed ................................................ 58BMS Systems Comparison Table .............. 59

CHAPTER 10 MOTORS .................................. 60

Electric Motor introducti on ................. 60

DCMOTORS.................................................... 61

Mechanically communtated .................... 61

Permanent Magnet PMDC Operation ..... 61

Wound field WFDC motor ........................ 63

Shunt Field ................................................ 63

Series Wound ........................................... 64Compound Wound ................................... 65

ACMOTORS.................................................... 65

Brushless or Electronically Communtated 65

Permanent Field Operation ...................... 66

Wound Field Operation ............................ 68

Induction Motor Operation ...................... 68

Switched Reluctance Operation ............... 70

MOTOR SPECIFICATIONS.................................... 71

Additional INFORMATION on Motors ...... 73

CHAPTER 11 MOTOR CONTROLLER ............... 75

DC MOTOR CONTROLLERS.................................. 75

Contactor as a Controller ......................... 76

Resistor Speed Control ............................. 77

Field speed Control ................................... 77

Electronic DC Speed Control. .................... 78

Forward and reverse control .................... 79

DC Controller wiring diagram .................. 79

DC Controller Specifications ..................... 80DC Motor Controller Kits .......................... 81

ACMOTOR CONTROLLER (INVERTER) .................. 81

AC Motor Controller Kits .......................... 83

Encoder .................................................... 84

AC Controller wiring diagram ................... 84

AC Controller Specifications ..................... 85

CHAPTER 12 ELECTRICAL CIRCUITS &WIRING 88

wiring diagram ........................................ 88

circuit elements ........................................ 89

Wiring ...................................................... 92Electrical Leakage Test............................. 94

Mounting Plate ........................................ 95

CHAPTER 13 PERSONAL PROTECTIVE

EQUIPMENT ................................................. 97

Helmet ..................................................... 97

Neck Brace ............................................... 98

Seat Belts ................................................. 98

Racing Gloves ........................................... 98

Safety Glasses .......................................... 98

CHAPTER 14 FABRICATION MATERIALS ......... 99

Aluminum ................................................. 99

Steel ......................................................... 99

CHAPTER 15 ROLL CAGE ............................... 99

Roll Cage Mount ...................................... 99

Body Panels .............................................. 99

CHAPTER 16 RACE PREPARATION & RACE ... 100

Practice Racing ...................................... 100

Practice Pits ........................................... 100

Safety training ....................................... 100

Acquire Radios ....................................... 100

Develop Race Strategy ........................... 100

GLOSSARY ................................................. 101

BIBLIOGRAPHY ........................................... 105

APPENDIX .................................................. 106

APPENDIX A-ANATOMY OF A RACING TEAM...... 106

APPENDIX B-BOLT CHART .............................. 112

US Bolts ................................................. 112

Metric bolts ............................................ 113


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FIGURES AND IMAGES

Figure 1 Cost Breakdown .. 12

Figure 2 ............................. 16

Figure 3 ............................. 17

Figure 4 ............................. 18

............................... Figure 5

.......................................... 19

Figure 6 ............................. 19

Figure 7 ............................. 20

Figure 8 Figure 9 ....... 20Figure 10 Figure 11 .. 21

Figure 12 Figure 13 ... 21

Figure 14 ........................... 22

Figure 15 Figure 16 .. 22


Figure 19 Front Bumper .... 23

Figure 20 ........................... 25

Figure 21 ........................... 26

Figure 22......................... 26

Figure 23............................ 27


Figure 26............................ 29

Figure 27............................ 30

Figure 28............................ 31

Figure 29............................ 35

Figure 30 Figure 31 . 36

Figure 32 Figure 33 ... 37Figure 34............................ 39

Figure 35 Figure 36 .. 40

Figure 37 Motor Mount

Figure 38 Motor mount

bracket 42

Figure 39 battery made of

cells in connected in series 48

Figure 40............................ 51


Figure 43 ............................ 62

Figure 44 ............................ 63

Figure 45 ............................ 64

Figure 46 ............................ 65

Figure 47 ............................ 69

Figure 48 ............................ 69

Figure 49 ............................ 76

Figure 50 ............................ 77Figure 51 ............................ 78

Figure 52 ............................ 79


Figure 56 ............................ 83

Figure 58 ............................ 89

Figure 59 ............................ 93

Figure 60 ............................ 96

Figure 61 ............................ 97
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BACKGROUND

The 2012 evGrand Prix Collegiate Program represents an innovative, team-based approach to developing the nextgeneration of automobile powered by electricity. The vision of the founders is to make this a national event, withracing teams coming from across the country to showcase their expertise by competing with the best and brightestfuture electric vehicle designers, engineers, enthusiasts and racing teams!

The purpose of this program is to accelerate innovation through education by encouraging college students tostudy science, technology, engineering and math, and pursue a career in the electric vehicle industry. This is alearning-by-doing reality based environment. Using electric powered racers as the focus, the program inspiresstudents to commit their creative energies to develop future electric vehicle technologies--technologies that willsecure sustainable and environmentally responsible transportation for future generations.

To compete in the evVehicle Grand Prix, students organize teams to design, build, and promote the events and

electric vehicle technology. Teams partner with industry, government agencies, and community outreachprograms which help to fund the program.

While there may be other series of electric motorsports that focus on running fast, the EV Grand Prix is focused onproviding an affordable educational venue for students to learn, design, drive and race an electric vehicle. It isimportant to understand that the real winners are those students who complete a racer and bring it to the track.These are the students who have the fortitude and ability to complete a complex project. Coming across the finishline first is icing on the cake.

The winner of the season series is the team that best blends vehicle design, race placement, educational outreachand optimal efficiency over the seasons events. Qualification runs , solo runs and sprint races may also be run aspart of the season event calendar, as college teams from across the nation come together and compete for

scholarships and bragging rights.

The future of transportation is changing and the Purdue Electric Vehicle Grand Prix looks to charge the innovationof personal vehicles with new and exciting technologies learned in the classroom and proven on the track. Join usas we develop new modes of transportation for the future fueled by clean and renewable energy.

In 2012, Purdue University is hosting two race events, evGrand prix at Purdue and the evGrand Prix at theIndianapolis Motor Speedway. In addition outreach, efficiency and technical events are also on the seasonschedule and will count for the season championship.


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EV GRAND PRIX HISTORY

The evGrand Prix was launched in 2010 as part of Purdues electric vehicle initiative. Funded by a $6 millionfederal grant, Purdue partnered with the leading technical universities and colleges in Indiana to establish a

program to educate and train the workforce needed to design, manufacture and maintain advanced electricvehicles, and formed the Indiana Advanced Electric Vehicle Training and Education Consortium (I-AEVtec). The I-AEVtec will develop and offer Certificates, as well as Associate degrees for training vehicle technicians, BS and MSdegree programs for design and manufacturing engineers in the electric vehicle industry and a Certificate programin electric vehicle safety for emergency responders. A leading engineering and technology university, Purdue seeksto train students and the Indiana workforce to deliver and maintain the electric vehicles of tomorrow.

Purdue University hosted the inaugural ev Grand Prix regional race on April 18, 2010 which was held at the PurdueUniversity track in Lafayette. The inaugural event was organized by students from the Electric VehicleEngineering Projects in Community Service (EPICS) teams and students enrolled in electric vehicle courses.

In 2011 Purdue hosted the second reginal evGrand Prix at Purdue on April 30, 2011. With two regional races

under their belt, Purdue opened up the series to the nation, inviting post secondary schools to participate in thefirst evGrand Prix at Indianapolis. This was a history making event as 30 racers took the green flag and for the firsttime in its 100 year history electric vehicles competed wheel to wheel at Indy!!!


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CHAPTER 1 TEAM

ASSEMBLING A TEAM

Assembling the perfect team is one of the most difficult things to do. A good team pools people of differentbackgrounds and abilities to complete a similar project. Those people then work together in order to besuccessful. Hard work, a positive work ethic, and the ability to research are essential to completing this build.Keeping the team together and on task ia a major a challenge for team leaders and advisors.

TEAM ROLES

Below we will outline key personnel to any electric vehicle racing organization.

Advisor:It is important to emphasis that the teams are led by students and that students are able to make mistakes in a safemanner. Having a Faculty from the home institution in charge or as an advisor is needed for any race team to

function. A faculty is preferred as the representative of the institution and will will represent the team to thegoverning organization and insure that all school policies are followed. The advisor can also help with thescholoraly based events. The advisor will oversee activities and insurea safe work environment. It is hoped thatevery team would have an adult advisor but it is essential that there be at least one advisor per institution.

Each team should consist of at least six people. The Driver and Crew Chief and the Scorer are required positionsthe three others can serve various roles as crew members.

Driver & Driver Tips:Becoming a race driver is not as easy as many believe. Drivers are atheletes with good instincts coordination andmental focus. A good driver also has a working knowledge of the technology built into the vehicle. Successfuldrivers must be willing to help lead the team and work in public relations and team funding and promotion.

Research: extensive research on the background of mechanics and driving. The sooner one begins schooling , thebetter chance at becoming successful behind the wheel. Read everything about the sport of racing performancevehicles that you can. This includes books, magazines, mechanic's manuals, textbooks, etc.

Go to race tracks. Talk to race track employees. Speak to drivers, crew members and anyone else involved on a raceteam. The more people in the field you approach, the more knowledge you can add to your repertoire and the morecontacts you will have when it is time to start getting more serious.

Experience: Experience and research go hand and hand. Once you have gained a significant amount of knowledgeit is time to acquire hands on experience.Try your hand at driving at a concession track. Getting a feel for what it is like driving in traffic at speed will giveyou an idea if you have what it takes to become a race driver.

Get a job at a race track. Sell tickets. Become an usher. Just make sure you are involved with the day-to-dayoperations that help make a racetrack a profitable place to recreate.


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Volunteer to help out a race team. Sweep the floors clean the car. Get up close and personal with people in thebusiness. Make sure they realize you are serious about learning. Work part-time for a mechanic. Go racing everychance you get. Seat time is everything, no matter what vehicle you are driving

Attend a Race School: Attending a race school is essential for the aspiring driver. Not only will it provide a morethorough and well-rounded education, but will also give future drivers a chance to compete against those that havetheir same level of skill and experience. Working with an experienced teacher will minimize problems andaccelerate your learning process. Before choosing a school, keep in mind that the some well known schools are notalways the best for you. Do some research before committing to a specific one. Also, bear in mind that the type ofracing you are pursuing will determine which school you attend as well.

Practice Racing: Seat time is the most important commodity for a future racecar driver. Get behind the wheel asoften as you are able to. Utilize your time at race school wisely, as this is the perfect opportunity to gain experienceimprove upon your skills and hopefully convince a sponsor or race team to take you on.

Team Manager - This is the business manager for the team. Contacting and working with sponsors, organizingshows, ordering parts, keeping others working on schedule, travel logisitics are just some of the tasks that must becoordinated for a team to be a success.

Crew Chief - The Crew chief is the technical spokesperson for the team. The Crew Chief will direct the othermechanical and electrical crew members. The crew chief can serve as the spotter and is typically incommunication with the driver.

Scorer - In addition to electronic scoring, a manual scorer is essential to insure the team is being scored properly.Scorers must be schooled in the system being used by the event organizers. This can mean anything from countinglaps to monitoring the karts efficiency. The scorer looks out for the well being and placement of the team

Electronically Knowledgeable Person - Designing an electric vehicle consists heavily in understanding electronics.

Understanding even basic circuitry is required in order to not only design a racer, but wire it. The ideal personshould know circuit basics, understand power as it pertains to movement as well as battery storage, andunderstand the individual components from the controller to the electric motor.

Mechanically Knowledgeable Person - Complementing all the electric aspects are all the general mechanics of theracer. Understanding gearing, being able to repair brakes, and being able to work with general tooling will help anyteam complete their project faster. Racer set up is critical to winning!


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GENERAL TEAM ADMINISTRATION

A budget is generally a list of all planned expenses and revenues. Before you begin to create your budget, it isimportant to provide as much detailed information as possible. Ultimately, the budget should be generated on a

spread sheet and converted to a ledger. Computer programs such as Excell are excellent for this. The budget willshow where your money is coming from, how much is there and where it is all going. Outlined below are some ofthe expenditures you will need to budget for an evGrand Prix team.

TRAVEL EXPENSES

One of the most underestimated costs in a racing team is traveling from event to event. Traveling can consist of theentire team going to practice tracks to races, and to outreach events. Miles accrued can add up over a short time iftravel is not planned and multiple vehicles are used. Travel expences may also include food on the road, rentalvehicles such as vans and accommodations for events.

TOOLS

Tools are the facilitators of any hands on project. Without tools, the project cannot be started or completed. Beloware lists of two sets of tools. There are necessary tools that you will commonly use throughout the building andrunning process and more advanced tools for advanced fabrication work. The advanced tools listed are not a musthave. These items may be available at the institution for team use. Teams may also secure the services of a localfabricator to assist with the construction process. Tools should be organized in tool boxes for quick access. Onebox should be a hot pit kit that contains only the tools and equipment your team needs for a pit stop for batterychange, tires or adjustments. The remaining tools would be kept in a box in the paddock area. Institutions withmulitlple teams may also have a special tool box which contains special tools which are shared among teams.

Necessary Tools Advanced ToolsAllen Wrenches Sheet BenderWire cutters Tube Bender

Wrench Set Tig WelderDrill Hand /bench GrindersSocket Set Drill/PressHammer Tire changing equipmentScrewdriver set Alignment gaugesVoltmeter/Ammeter/Ohmeter Tire temperature gaugeWire crimper Weight ScalesJigsaw or saws-all Air tankWire strippers Punch, chisel setSoldering Iron Portable viseTape Measure C Clamps

RACER COSTS

Below is a spreadsheet outlining racer fabrication and assembly costs that were accrued by a student team duringtheir build. Dont let the bottom line discourage you. Many teams have built and fielded racers for less money. Inkind products, used chassis and components can help reduce the costs. Another factor is that once you have the


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racer built, you can run it for more than one season allowing your team to spread costs over several years. Thehigh visibility events and intercollegiate competition should make this a fund raising venture not a fund buster.

Figure 1 Cost Breakdown

REGISTRATION

To insure entry into the race various forms and payments for registration and identification must be completedbefore the race. There are deadlines for the various forms and fees. Commuications between teams and the eventorganizers are key to meeting deadlines. Fees from individual teams may also be assessed to support yourinstitutions commitment to the national organization.Spare parts must also be budgeted for. Items in this category include racer parts that are subject to loss, wear anddamage or are needed to make adjustments in the set up. Typically this includes wheels and tires, suspensioncomponents, fasteners, fuses, chains, sprockets, and similar parts need to be on hand at the track.

Item Manufacturer Model Price Qty. Total

Rolling Chassis Margay Bravia 1.4 $2,995.00 1 $2,995.00

Motor MARS ETEK-RT $525.00 1 $525.00

Controller Alltrax AXE7234 $480.00 1 $480.00

Batteries ThunderSky LFP60 $120.00 48 $2,880.00

Battery Shipping Freight Estimated $2.00 24 $48.00

Contactor Albright SW-180 $85.00 1 $85.00

Throttle Curtis PB-6 POTBox $85.00 1 $85.00

Charger Zivian NG1 $565.00 1 $565.00

Power Connectors Anderson 175A red #1/0 $18.50 4 $74.00

Connector base Anderson Double pole base $12.50 2 $25.00

Connector Handle Anderson Locking Handle $25.00 2 $50.00

Fuse Ferraz Fuze 200A/150V $44.00 1 $44.00

Main Wire General Cable 1/0AWG $6.00 30 $180.00

Ring Terminal Thomas & Betts #J972 $4.00 25 $100.00

Small Wire Local 12-16AWG $0.25 25 $6.25

Safety Switches Mouser Many(estimated) $25.00 1 $25.00Small Connectors Local 12-16awg 100/bag $10.00 1 $10.00

Throttle Cable Fox Valley 6 with plastic $5.00 1 $5.00

Chain EK #35 96 links $20.00 1 $20.00

Rear Sprocket Rocket Sprocket #35 52-72Teeth $17.00 1 $17.00

Motor Sprocket McMasterCarr #35 25teeth $20.00 1 $20.00

Battery Boxes Custom To Match LFP60 $100.00 2 $200.00

Motor Mount Custom To match ET-RT $60.00 1 $60.00

Controller Mount Custom Fit Rear Axel $40.00 1 $0.00

Nerf Bars Custom To fit battery Box $80.00 2 $0.00

Roll Cage Custom To fit Chassis $2,000.00 1 $0.00

Seat belt Simpson 5 way harness $110.00 1 $0.00

Arm Restraints Simpson Simpson Arm Re $38.95 1 $0.00

Helmet Vega Mach one $105.00 1 $105.00

Racing Suit Bell Velocity Suit $80.00 1 $80.00Racing Gloves Azusa Nylon Karting $25.00 1 $25.00

Neck Collar Simpson Nomex Round $37.00 1 $37.00

Hardware Misc Misc Hardware $150.00 1 $150.00

Shipping Misc Shipping for all(est) $500.00 1 $500.00

Totals $10,042.25


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Expendibles are items that are used up in the process of running or working on the racer.These items are usually not thought of until last and though cost little per unit add up quickly over the season ofracing. Rags, oil, lubricants, suntan lotion, first aid supplies.

TEAM APPAREL

Drivers gear helmet shoes and suit must be secured and kept up to date.Team shirts, gloves and goggles must also be on hand.

TEAM REGISTRATION

Every team must register their school, racer, racer number, and individuals involved. Earlier registration insuresthe number chosen is the one assigned on race day.

INDIVIDUAL REGISTRATION

Each individual that plans on racing, being in the pits or being near the track must register as part of the team.

Individuals will be given passes allowing them into various parts of the track based upon registration. Drivers mustalso complete detailed forms proving driver eligibility.

MEDICAL FORMS

Each individual must complete and sign a medical form which states that the individual understand that theorganizers will not provide medical coverage and that participation in this event is voluntary.

LIABILITY FORMS

Each individual must complete and sign a form stating that organizers, sponsors and event personnel are notliabile and is understood by that person. Persons under the age of 18 must have a parent or guardians permissionto participate.

TEAM LOG BOOK

The Team log book is a summarization of all the necessary documents a team will need over the course of the

construction, practice and events. It should include the following sections:

a. MSDS sheets / chemical inventory

b. All Inspections records

c. Hazard Analysis pland. Safety Plan

e. Track / Practice log

f. Any equipment change out records which are needed (see kart spec for potential items)

g. Electric leak testing recordh. Kart weight analysis

i. Copy of team waivers, medical releases

j. Copy of submitted team information documents

k. Copy of any deviation requests submitted and EMT action

There are examples of these documents / templates on the web site under forms.


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SPONSORS AND MARKETING

SPONSORS

Racing is a business. It is also a show. Keeping this in mind helps to focus the fund rasing activity and theopportunity to run and operate an enterprise. Recognizing the high cost associated with fielding an entry andwishing to encourage the involvement of businesses in the EV Grand Prix, the EV Grand Prix endorses therecruitment of commercial sponsors for individual entries. Race teams and schools must clear their sponsorsthrough EV Grand Prix before entering into any agreement. Any information given to the EV Grand Prix beforerecruiting a sponsor will be held in confidence. No team can be sponsored by any organization or businessassociated with alcohol or tobacco, or dealing with items or services of a sexual or denigrating nature. Thisrequirement includes businesses that are bars, where the bar is not set apart separately from a family area. Therace director has final say on any discrepancies with this requirement.

Finding a sponsor does not have to be a difficult task. The first thing one should do when searching for a sponsor isresearch. Research will indicate whether a particular sponsor is already to contributing to other teams, or to other

organizations at the school. School policy as to solicitation of outside agencies should also be known prior tomoving forward on a sponsorship campain. This research can be done in libraries, by observing competitions in aparticular sport that the organization or person participates in, asking others what sponsors (if any) they have, bysearching Internet sponsor websites promoting for particular activities, by investigating magazines or publicationshaving to do with the activity engaged in, and by inquiring to existing organizations having sponsored members orparticipants. Printed, electronic and social media may be means for finding potential sponsors. Look for unique fitswith the EV Grand Prix goals and nitch interest areas. Think about what your team can do to help promote thepotential sponsors service or product. Look for products or services that you need or that you could test andpromote by actually using on your racer. In kind parts and donated services are just as good as cash.

Sponsorship letters and proposal documents are of vital importance when applying for sponsorship. Brochuresare also good for handing out at shows and campus events for soliciting smaller donations such as send a student

to INDY fundraiser. The sponsorship letter shows that the applicant has given thought to what the individual ororganization wants to accomplish. It helps if you have a name of the contact person at the particular organizationbeing solicited. Cold calls and emails many times go unread or unresponded to. The documents should beorganized to provide the potential sponsor with basic statistical data such as how many individuals on the team orin the organization (if more than one person), location of the team, organization or individual and what type ofawards or special honors any participants have received. Most important is a section or paragraph describing theprestige and opportunity for exposure to the public that national competition will provided to the sponsor.

After the basic introductions of important details and statistics, sponsorship proposals would benefit fromdiscussing the sponsorship they desire. Explaining goals of the team/individual/organization is a good start. Aschedule of levels of cash and inkind contributions and what you will do for them, should be included for sponsorsto see what they get for their contribution to your team. This introduction sets up in the potential sponsor's mind

what to what benefit and ends the sponsor's money would be spent. Explain what the sponsor would gain fromsupporting your team as far as how many events and locations that you expect to participate per sporting season.Location and exposure are important to potential sponsors as it draws attention to them and is a form of marketingtheir business. It is also a good idea to specify (if possible) the length of the sponsorship and the amount of moneyneeded. Some sponsorship agreements are long term and some are short termed. Most sponsorships arecontracted agreements and so it is important for an individual or organization to make clear what they want andwhat the sponsor is willing to contribute before any deals are made.


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Follow up is most important to sponsors, be sure to include sponsors in news letters and invitations to events.After season thank you letters with pictures and information as to what events and shows where you promotedtheir product or service is the key to securing sponsorship the following season and for establishing goodwill withyour institution. Most of all be sure you deliver on those promises you made to attend events and promoteproducts.

PROMOTION EXPENCES

Some of your funds need to be reserved for promotion of your marketing partners and team. This is crutial to keepsponsors happy and advertising your team. Fliers, newsletters, website host cost , display posters fit into thiscategory. These expences typically will be in support of your teams outreach activity. Dont forget to add in thecost of food and drinks for those recruitment parties and at your hospitality tent at the events.

FINDING WORK SPACE

PLACE TO WORK ON RACER

Find a location that is large enough to store and secure your racer, tools, and extra parts while also leaving room towork on the racer. Make sure you have access to electricity and be sure that the owner of the property is awarethat you will be using lots of electricity (charging batteries and running power tools) and that you may be workingmany hours of the day. Lastly, try to find a location close to campus. This will make it easier for your team to getthere and you wont spend all of your time traveling.

If your team is affiliated with a specific academic department, check with them to see if they have an open roomthat your team can work in. The team advisor should be helpful in finding spaces at the home school for you towork. Ask your instructors about including project elements of the design and build into your class experience.Teams that are affiliated with a Greek organization typically set up a shop in the basement of their house. If your

team does not fall into one of these categories, you will have to search a little more. Talk with friends aroundcampus and ask if they know of any garages for rent off campus. Also, check with various real estate agents thatrent houses and apartments in the area. They may know of an open garage or shed in the area. Sponsors may alsobe able to help provide or locate space especially if its a fabrication shop.

PLACE TO RESEARCH AND PLAN

Try to find a place where your whole team can sit down and plan your racers design. This can be a computer lab orquiet room on campus. Access to Internet and a white board are very important to have so that you can researchand draw up designs. The location should stimulate an open and thoughtful design process. Coffee houses andinternet cafes may also provide an area for small groups to gather. This adds to the fun and socialization that ateam experience can provide. Through out the entire design, fabrication, and racing of the vehicle the team should

enjoy working.

PLACE TO PRACTICE AND TUNE RACER

Once the racer is running you will need a safe area to tune, test and practice with your racer. Research race trackswithin reasonable driving distance in your area. Once you find a few tracks near you, call them and ask if they allowopen practice sessions. Some tracks will allow drivers to bring their own racers and others will not. Start lookingfor a track early because this will be very important as the race approaches. Open parking areas at the school are


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very inviting for testing. Avoid the temptation of running down the street to check out the machine. Check withyour institution authorities as to places where you can go to test and what they may require as safety precautions.Caution is the important rule here. All out speed on a non secured parking lot with ditches, drain covers, cars andcurbs is a recipe for disaster. Running at a reasonable speed to demonstrate system operation or shaking out aproblem may be conducted provided the operational area is blocked off and hazards are considered.1.4Instructions/Rules

You can find the instructions and rules on the EvGrandPrix website. Your team should all read these overthoroughly so that you know and understand what is allowed and what is not. It is your responsibility to know andfollow the rules and regulations. The best method is to first read the rules of start to finish. The team shouldhighlight or mark any rules that are confusing or misleading. Any rule clarification can be done through the EVGrandPrix organization. Once the rules are understood teams can begin their design. It should be kept in mind thatteams should always clarify designs with the EV GrandPrix organization to keep their designs to within racespecifications.

SCHEDULE/TIMELINE

Figure 2

Above is asampletimelinefrom the2011 raceyear thatshould

give your team an idea of what you should be doing and when. This is by no means an exact timeline, but shouldgive you a general idea of the time involved for each step. Many project management software programs may beincorporated to help your team keep on task and insure your team will be ready to take the track when you arriveat the event.

With organization, commitment and hard work, it has been shown that teams can build and field a racer starting inJanuary. We recommend seeking student members, fund raising and outreach begin in the fall when school starts.This is typically when students are looking for organizations and extracurricular programs to join.

Institutions that have not been previously fielded an evGrand Prix racer, need to get started as early as possible toinform the appropriate institutional offices and determine the specific requirements to be met for your institution

to participate.

Contact the EvGrandPrix Organization regarding ordering tires, batteries, etc,as these may be covered under ablanket agreement which may reduce your expense.


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CHAPTER 2 MECHANICAL

Once your team is funded, you are ready to design, order parts and build your racer. The information in this

section will assist you in what you should look for when designing your racer and ordering your parts. This sectionwill take you through each part of the racer. It will describe what the part is, its purpose, and what specifications itmust meet in order to be used in the race.

Complete racer less safety cage

Figure 3

CHASSIS

In the final construction of the racer we will work our way front to back and bottom to top. The final constructionand ultimately the project are only as strong as each individual part. Designing as well as fabricating eachindividual part will be discussed however is left up to each team. Bear in mind this is only a guide, and design iscompletely up to the team. There are many ways to mount, secure, fasten, and otherwise design parts. We hopethat this guide will give your ideas that you can build upon and innovate yourselves.First well begin with acompletely bare chassis, simply a frame and as the guide continues parts will be added. By the end of the guide, youshould have a completed racer.


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Figure 4

FRAME

A critical component of a speedy and strong racer is the frame also known as the bare chassis. The frame providesthe suspension and support of all the other components. A precisely-designed and sturdily built frame keeps yousafe and your tires glued to the track while racing through busy tight corners at top speed. Spinning out of controlis much more liable to happen with an inferior frame. Inferior design, welds and material selection can causeserious accidents, injury and DNF (did not finish).

The evGrand Prix specifications call for the racer to be built on a go-kart frame. The frame or chassis is made fromstrong steel tubing since kart based racers don't have a suspension the chassis must be rigid enough not to breakunder the strain and flexible enough to act as the suspension. Challenging corners are a major aspect of racing andcan be very tough on chassis, so some flexibility is crucial for maneuvering although some stiffness is crucial forstrength.


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VEHICLE MEASUREMENTS

Figure 5

Chassis Diagram

Figure 6

30-55 inch

Tread Width

40-66 inch Wheelbase

Roll cage

must not

extend

beyond

center


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Frames can be either straight or offset. The chassis are given their respective names based on the position of thedriver. If the driver sits in the middle of the go cart it is known as a straight frame. If the driver sits on the left sideit is an offset frame. Straight chassis are usually used in for road courses with left and right hand turns whereasoffset frames or chassis are most commonly used to bias weight toward the inside or speedway racing or ovaltracks. Speedway racing is most commonly the name given to oval tracks encompassing all left turns.

Figure 7

Enduro and upright sprint frames are also available. Enduro frames are of the laydown style where the driver isnearly in the prone position. This style of chassis is not permitted to be run in the EVGrand Prix. The Upright orsprint frames is the choice for the EVGrand Prix racer. This chassis design though not as aerodynamic, seats the

driver more upright to take advantage of the seat belt and provides better visibility. Be sure to check thespecifications for the minimum angle when positioning the seat for the driver.

Figure 8 Figure 9

Most karts are of the open frame design where the driver is not strapped in and literally rides on the kart. Uponroll over, the driver is ejected similar to that of a motor cycle. Drivers are vulnerable to abrasion and injury bycontact with other racers. Drivers typically wear leather suits similar to motorcyclists to minimize such injury.Open frames are not allowed to compete in EVGrand Prix events.


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A caged frame has a roll-over cage attached or made part of the frame design that encircles the occupant of a kart.Its most important objective is to prevent harm or injury during a crash, principally in a crash involving a roll-over,but additional can also help reinforce the chassis. Typically the cage kart makes the roll over cage an integral partof the frame to reduce weight. This design works well on non-kart racers with suspension but the added stiffnesscan be a detriment if the frame is made too stiff to conform to the track. Caged frames are allowed in to compete inthe EVGrand Prix provided they meet the material and dimension specifications.

Figure 10 Figure 11

Most EVGrand Prix teams, just starting out, choose an open frame design and make appropriate modifications toattach a removable safety cage. In this approach the cage, which is described later, is mounted to allow the frameto flex while being strong enough to remain attached during mishaps.

The best frames or chassis permit easy altering or adjustment of the stiffness to adapt handling for weather andtrack conditions. Varying the stiffness is done by adding or removing stiffening bars on the rear, front, and side ofthe chassis. Stiffening up a chassis can overcome chatter or bounding when making a high speed turn... Excessively

stiff chassis, lacking enough flexibility will not conform to the surface creating poor steerability and can createfracture. The appropriate amount of flexibility and stiffness will allow a driver to keep a truer line through trickycornering instead of drifting sideways. This will improve performance and increase the lifespan of the chassis. Youmust consider the extra battery weight when making your adjustments and selecting a chassis.

Figure 12 Figure 13


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Figure 14

FRAME CONSTRUCTION STANDARDS.Frames may be custom built or purpose built. A custom built frame is typically a one-off shop built assemblyfabricated by the race team or for the race team by a non-recognized or non-certified constructor. To be used incompetition these frames must be made of the material and use welding standards and dimensions listed in theseries vehicle specifications document. Shops built frames are subject to close scrutiny at technical inspection andwill be allowed to compete only at the discretion of the technical inspector. You should be prepared withdocumentation as to material and weld quality when presenting a racer with a non certified frame for inspection.Having the frame inspected by an official prior to its first competition and documented in the vehicle log mayminimize anxiety and disqualification of the racer from competition come race day.

Figure 15 Figure 16

Purpose built or so called factory frames are permitted in competition. These frames are typically identified byfactory placed welded on tags with make, model, serial numbers and WKA or ICA certification numbers. Keepingthis tag clean and visible is essential for quick inspection. Use clear finish to keep the tag looking good. Theconstruction of these frames is assumed to be engineered and have demonstrated performance over numbers ofunits and years of service and are not subject to the material or welding specifications. Any factory frame without


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a certification tag will likely be treated as a one-off frame and be subject to scrutiny by the technical inspectors. Asfactory frames may or may not use the specified welding or materials listed in the specifications, you need to beprepared to convince the technical inspector of the authenticity of the frame.

Figure 17 Figure 18

It is important that any modification to the frame follow the vehicle specification document. Permanent additionsof seat supports, frame members, tabs, brackets or mountings must be made using the welding techniquesspecified. It is specified that welded joints be inspected prior to painting the frame. A series of pre-paint picturesmay also prove useful when being questioned at later technical inspections. Some racers prefer to clear coat theirframe rather than using an opaque color to place emphasis on the quality of construction and allow quickinspection

As the chassis frame is the largest component of the racer. A rolling chassis includes the frame, wheels, tires, brakecaliper, brake master cylinder, brake lines, steering rod, tie rods, spindles, steering wheel, pedals for brake andacceleration, brake linkage, throttle cable, seat mounting points, seat belt mounting points, bearing cassettemounts, bearings, and axle.

FRONT BUMPER

The front bumper is necessary to absorb energy in acollision. This is a manufacturers recommended safetydevice and should be incorporated into your design. Thefront bumper can either be bolted to the frame or in somecases has a special harness that also helps spread the forceof impact. It is important that your front bumper be secureas this is a common collision impact zone.

Figure 19 Front Bumper


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NERF BARS

Normal racers have nerf, or side bars. These are usually expendable chrome or aluminum bumpers on the side theracer that prevent other racers from protruding close the driver. In this race it is recommended and stronglyadvised to construct new bars that would hold the weight of batteries and other components placed on them. Nerf

bars can be as simple as bending pipes in two spots to attach to the previous plugs that the weaker nerf bars wereonce attached to. You will most likely want the nerf bars to have battery box mounts

WEIGHT ANALYSIS

Max. Weight of Racer (with driver) (Max 625 lbs.)______________

Weight of Racer (without driver and Batteries) ______________

Weight of Batteries ______________

Percent of Battery vs. Racer C/B ____________%

Weight for the vehicle and driver cannot exceed 625 pounds. Battery packs alone

cannot exceed 50% of the total vehicle weight as weighed without the driver or battery packs.

FASTENERS

An understanding of the mechanical elements of a racer is not complete without a discussion of fasteners.Fasteners are what hold the mechanical parts together when the vehicle is running and allow parts to be removedfor service or replacement. Often fasteners are taken for granted until a lost race or accident is blamed on a

fastener failure which later was found to be a result of miss application of the part or improper installationtechniques. Fasteners include bolts, nuts, screws, and a variety of special purpose devices that can be used tohold parts together. Fasteners need to be installed properly to work. Thread types for nuts and screws mustmatch. Knowing the difference of strength insures you have a fastener that will hold the tensile load. Use of thetorque wrench on screws insures that the fastner is proplerly tightened. Use manufacturers recommendations andfollow the race specifications when applicable. The charts in Appendix Bare provided when specific recommendations are not available.

More Info on Fastenershttp://www.boltdepot.com/fastener-information/ HTTP://WWW.ENGINEERSHANDBOOK.COM/TABLES/TORQUE.HTM
http://www.boltdepot.com/fastener-information/http://www.boltdepot.com/fastener-information/http://www.boltdepot.com/fastener-information/


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Chapter 3 Driver Restrating System

SEAT AND SEAT MOUNTS

Seat Mounts

Figure 20

Seat mounting should be done with the racer on scales. The seat mounting position will make a huge difference inbalancing the racer. This is critical and the driver will be needed to get this correct. see racer set up video beforemounting the seat!

Illustrated above are the mounts in which the racer seat is attached, the rear mounts are not shown on thisdiagram; however they are of similar size. Usually they are metal tabs with holes in them behind the steeringwheel and before the back axle. Seats may have to be drilled to customize the seat position. Holes, cracks anddamage must be repaired to maintain seat strength. Racers can have the seat positioned either centered or over toone side depending on driver preference and racer design. Check specifications for seat back angle.

DRIVER RESTRAINT SYSTEM

All belts must be securely fastened to the chassis frame or to a fixed bracket system bolted or welded to the frame.No belts or belt supports may be attached to the safety cage, nerf bars, or bumpers. Commercial restraint systemmounting hardware is recommended. U-bolts are not permitted to attach the seat belts to the frame. The shoulderharness bracket system shall be designed so that a load applied in any direction will not result in any movement ofthe shoulder harness bracket. Shoulder harness straps/belts must be positively retained to any harness support.For example a metal rod with cotter keys on both end so that straps do not fall off of shoulders. Mounting bracketsmust be installed at an angle that is compatible with the direction of pull on the webbing under full load. Aminimum specification for bolts and washers to attach the driver restraint system hardware is Grade 8. Under nocircumstances are bolts inserted through belt webbing acceptable for mounting. Belt webbing may be required tobe replaced if the webbing shows signs of wear, tear, and age. Belts with webbing inspection date of more thanthree years may not be acceptable.


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Driver Restraint System/Mount

What the driver restraint systemshould look like.

Mounting plates must have a properdirection of pull

Figure 21

Harness/Harness Mount

Harness Mount Harness Proper Belt Usage

Figure 22 (Use commerciallymanufactured belts and mounting systems)

SEAT BELTS, HARNESS AND ARM RESTRAINTS

A seat belt, sometimes called a safety belt, is a 5 point safety harness designed to secure the occupant to the racerto minimize harmful movement, contacting interior elements or ejection that may result from a collision or asudden stop. Belts must be SFI rated. belts and harnesses are also strongly recommended. Belts that exceed threeyear tested date may be sent in to SFI for re-evaluation. Safety belts are required to have a width of at least threeinches (3). The intention for arm restraints is to keep their arms within the roll cage.
http://en.wikipedia.org/wiki/Safety_harnesshttp://en.wikipedia.org/wiki/Vehiclehttp://en.wikipedia.org/wiki/Collisionhttp://en.wikipedia.org/wiki/Collisionhttp://en.wikipedia.org/wiki/Vehiclehttp://en.wikipedia.org/wiki/Safety_harnesshttp://rds.yahoo.com/_ylt=A0WTefX1IYVM02cAN4WjzbkF/SIG=12oljoagg/EXP=1283879797/**http:/www.proformance.com.au/Images/Klippan-5-Point-harness-760.jpg


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Seat Belt Mount

Use commercially available mounting brackets to insure the safety of the driver. The mounts must be TIG weldedto the frame.

Arm Restraints

Arm Restraints

Figure 23

All racers must be equipped with commercially made arm restraints, which do not allow thedrivers arms to extend beyond the roll cage. The arm restraints should be worn according to themanufacturers recommendations. They should also be a different color than the drivers suit.

Seat MountingThere are 4 points that are used to mount the seat. They arelocated under the steering wheel and on 2 tubes that extendupwards from the frame. The seat should be mounted in such away that the driver is comfortable for long periods of time. Thisincludes if need be, buying a larger seat to accommodatehim/her. Remember seat mounting had a huge effect on theracer setup review racer setup video before mounting seat.

SEAT BELT MOUNT

First take the seat belt out of the box and find the proper orientation. There should be 2 side mounts and one rearmount. First mount the rear attachment.


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There is a bolt located on the bar that protrudes behind the seat. The bolt should be facing the rear of the racer andbe located right above the axle. Slide the mounting bracket over the bolt and then place a distorted nut on the bolt.Tighten all the way down. Next find the 2 tabs located on either side of the seat. Take the side mounting bracketsand line them up with the holes in the tabs. Place a grade 8 Bolt through both holes and tighten with a distortednut. This is how the seat belt is held on the racer. Have the driver sit in the seat and put the belts on them. Tightenthe belts so that it holds the driver in place and allows for as little wiggle room as possible. Once tightened, useeither duct tape or zip ties to collect and hold out of the way any stray pieces of the seat belt so they do not drag orget caught in any moving components.

HEAD REST

The head rest is an important component for safety. Although the head rest was allowed to be mounted on the rollcage in previous years in the 2011 event the head rest must be mounted from the frame of the racer. This meansthat it must be attached to the chassis. While constructing your head rest make sure that it is aligned with thedriver in X, Y and Z planes. The headrest should be positioned toward the middle of the back of the drivers helmet.


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CHAPTER 4 BEARING, AXLES, STEERING

Bearing Axle

Figure 24 Figure 25

The axle is located at the rear of the racer. It is supported by two bearing on either side of the racer allowing it tofreely spin. The axle supports the brake disk and slips through tire hubs for tires to attach to it. The bearingsattach to the axle to the racer.The axle is held in place with set screws on the bearing hub. It is recommended that shaft collars are added to theaxle support to insure the axle does not slip.

STEERING ASSEMBLY

Steering Assembly Components

Figure 26
http://rds.yahoo.com/_ylt=A0PDoS_5S_1MthwAPPeJzbkF;_ylu=X3oDMTBrODhwZHB2BHBvcwMxODUEc2VjA3NyBHZ0aWQD/SIG=1ldgoh8ip/EXP=1291754873/**http:/images.search.yahoo.com/images/view?back=http://images.search.yahoo.com/search/images?p=kart+axle&b=169&ni=21&xargs=0&pstart=1&w=800&h=800&imgurl=www.corsaracingkartamerica.com/images/CorsaSiteSkipperKart_5.jpg&rurl=http://www.corsaracingkartamerica.com/index.php?main_page=index&cPath=2_9&zenid=lbsp9327qs3hrvls6efhra2740&size=395KB&name=...+Cadet+Racing...&p=kart+axle&oid=1a223a1e43f7f307b9492b91d961b915&fr2=&no=185&tt=17800&b=169&ni=21&sigr=13ag8k1oj&sigi=120h7k5tb&sigb=12leqde00&.crumb=kQw7csSyuMy


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The steering assembly is what allows the driver maneuver on the track. The assembly consists of the steering rod,tie rods, spindles, and steering wheel. The front wheels are attached to the spindles. Spindles are attached to thefront axle of the frame with king pin bolts. These allow the spindles to swivel. The steering wheel is attached to ahub on the steering column. This column is attached to the spindles with tire rods near the front of the racer. As thedriver turns these rods angle the front tires in the direction the steering wheel isturned. A quick release typesteering wheel hub mount may be used to assist entry and exit of the racer when roll cage is in place.

Figure 27

Tie rod ends are screwed on to either a shaft or a tube. An important part is the jamb nut. After adjustment of toethe nut is jammed against the rod end to keep the rod from turning. It also stops fretting of the threads. It goeswithout saying what would happen if a tie rod pulls out when the racer is at speed or negotiating a turn.


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Figure 28

CHASSIS TUNING

Because a kart based racer has no active suspension and most rear axles are solid, the majority of the handlingcharacteristics are affected by tire selection and inflation, chassis stiffening, weight distribution and theadjustments of the steering assembly. In this section we will discuss the steering assembly; the remaining factorswill be discussed in other portions of this document.

The steering assembly may provide adjustable features to allow front wheel alignment. At a minimum the tie rodsprovide for length change to allow the front wheel toe to be adjusted.

Toe In/Out.-This is the angle at which the front wheels either point in towards each other, or away from eachother. Zero degrees toe in/out means that the wheels are parallel. Toe in/out is set by changing the length of the tierods. Always recheck the toe when making camber or caster adjustments.


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Other front end alignment adjustments to consider are caster and camber. Some racers have fixed caster andcamber built into the front axle or frame. Some chassis provide for adjustment for these alignment parameters.

Camber - The tilt of the tire as viewed from the front of the car. If the top of the tires lean toward the center of thecar then you have negative camber. If the top of the tire tilts out away from the center of the car then you havepositive camber. A camber setting of 0 means that the tire sits flat on the track. Maximizing the amount of rubberon the track is one of the aims of the setup. Camber is measured with a caster camber gauge. Camber may beadjusted by replacing front spindles. Some racers have adjusters to allow for fine adjustment.Adjusting camber can have a dramatic effect on the cornering of your car. Most oval track racers run negativecamber on the right side of the car and positive camber on the left. Optimum camber settings will result in morespeed and ideal tire wear.

The amount of static camber that you should run is a result of testing, pyrometer measurements, front suspensiongeometry and discussions with your car builder. Remember that poor camber settings will cause excessive tirewear. Camber settings set to extremes can reduce the braking ability of the car.

Camber Angle - This is the inclination inwards at the top of the king pin towards thecenter of the kart, and it is aimed at counter-acting the jacking effect of the castor: atthe same time it helps to produce a stronger joint, which will be able to withstand

higher shearing forces. Generally this angle is between 10 degrees and 12 degrees,and to allow the wheels to stand flat on the floor is offset by a similar angle on thestub axle.

Caster - This is the angle of the kingpin, which is the point around which the stubaxles rotate. This is one of the most important settings for inducing wheel lift duringcornering.


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Scrub Radius-This is distance from the center of the tire to the point where a line down the kingpin axis intersectsthe ground. Along with caster this affects wheel lift during cornering. Scrub radius is set using spacers on the stubaxle

King Pin Inclination-This is the inward lean of the kingpin, and it modifies the amount of camber change caused bythe caster when steering. It is not usually possible (or necessary) to adjust the KPI although some camber adjustssystems may let you do it.

Ackermann Steering.-Ackermann steering uses the angle of the stub axle arms (and often an offset on the steeringcolumn) to make the inner wheel on a corner turn more than the outside wheel. With cars this is used to reducetire scrub on corner, but of more importance to karts is the greater wheel lift effect caused by increasing the innerwheels turn when compared to the outer.

The Ackermann angle refers to the placement of the steering arms (when viewed from above), in relation to thechassis, and the rear axle. Ideally, lines projected through the center of the King Pins, and through the bolts holdingthe track rods, should meet at the center point of the rear axle. Some chassis designers will place the apex of theangle forward or behind the rear axle to change the scrub effect when turning. The effect of the angle is that theinside wheel always describes a smaller radius arc than the other wheel, when the kart is being turned this is


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most especially important at low speeds, and on tight corners. The length of the steering arm, in relation to thespade/drop arm, affects the speed of the steering reaction. A long steering arm causes slow but very lightsteering, whereas a short arm causes quick steering but requires greater effort.

Further Information on chassis tuning

http://racingarticles.com/article_racing-24.htmhttp://www.kartweb.com/TechArt/Chassis/setupfordummies.html

http://www.karting.co.uk/KandK/Tech/KartSetup.html

http://www.agcoauto.com/content/plugins/p2_news/printarticle.php?p2_articleid=176
http://racingarticles.com/article_racing-24.htmlhttp://racingarticles.com/article_racing-24.htmlhttp://racingarticles.com/article_racing-24.htmlhttp://racingarticles.com/article_racing-24.htmlhttp://www.karting.co.uk/KandK/Tech/KartSetup.htmlhttp://www.karting.co.uk/KandK/Tech/KartSetup.htmlhttp://www.karting.co.uk/KandK/Tech/KartSetup.htmlhttp://racingarticles.com/article_racing-24.html


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CHAPTER 5 BRAKING SYSTEMS

BRAKES

The braking system on these racers consists of a brake pedaland linkage, which leads to a master cylinder which actuatesthe rear caliper through dot 5 brake fluid. Be sure that brakeline doesnt have any bubbles and is completely filled. Therear caliper contains brake pads that have to be replacedwhen worn. These can also be adjusted closer to the brakeand to allow the brake disc more space. This adjustment is toallow the pads to be as close as possible to the brake rotorwithout rubbing when not engaged. As seen to the right, the

brake disc should be secure and in the middle of the brakecaliper. This ensures consistent as well as even wear on bothbrake pads.

THROTTLE

The throttle consists of a pedal and linkage attached to a throttle cable which is enclosed in a plastic sheath toprevent unwanted activation of the throttle. At the end of the throttle cable is an adjustment piece, which attachesthe cable to the potentiometer box and then can be adjusted for proper throttle response.

THROTTLE AND BRAKE PEDALSThrottle and Brake Pedal

Diagram

Figure 29

Each of these pedals is located at the front of the racer. The throttle is located on the right and responsible for theacceleration of the racer. The brake is located on the left and responsible for bring the racer to a stop. The throttlewill be connected to an electronic accelerator called the potentiometer using throttle cable or rod. The throttle


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cable is a steel wire that has the flexibility to travel down the length of your kart to where the electronics arelocated. A most important is the throttle return spring. Two springs are required to provide redundant return tostop.One should be located at the pot box area and be strong enough to pull back on the cable. Cables are designed topull not push. When a throttle rod is used the spring may be located on the throttle pedal. The second springshould be set up to return the potentiometer to zero should the cable brake.

BRAKE MASTER CYLINDER

Brake Master Cylinder similar to ones you may use

in your Racer.Brake master cylinder installed

Figure 30 Figure 31

Most modern racers use hydraulic brakes, though mechanical brakes may be used as long as they are powerfulenough to stop the racer according to the vehicle specifications. Connected to the Brake pedal is the Brake MasterCylinder is a large cylinder in a hydraulic system in which the working fluid is pressurized by a piston.

Brake Caliper and Disc

Illustrated below you will see the brake caliper and disc. The disc is attached to the axle which spins as you racedown the track. When you apply the brake, pressure from the master cylinder forces liquid down the brake lineand then the caliper squeezes the disc causing it to stop spinning.


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Brake Caliper and Disc

Figure 32 Figure 33

The brake caliper is attached to the chassis. A spring on the brake pedal is used to return the master cylinder andrelease the caliper. Brakes are required on the rear axle. If desired brakes may be also fitted to the front wheelsfor increased stopping power and system redundancy.

TIRES, RIMS, HUBS, AND WHEELS

Tires are the part of the racer that contacts the racing surface. All of the chassis geometry, acceleration anddeceleration turning and handling come down to keeping the tire in contact with the surface of the road and the

friction of the tire to the surface.

Racing kart tire size is given by numbers such as 11 x 6.00-5, which is a different system than that used for

ordinary tires. In this example, 11 indicates tire diameter, 6.00 shows the tire width and the 5 indicates rim

diameter. Measurements are in inches but the figures are rough estimate. For more precise dimensions, refer tothe tire dimension chart below.

The first thing that must be determined for a kart tire proper inflation pressure if you want to get the best

performance from any individual kart tire. That is easily said, but the real problem is the word "proper" because

it meaning varies delicately with conditions such as driver, frame, course layout, road surface, weather and

temperature, to name but a few. The manufacturers limits of pressure is typically from 11 to 23 psi and the

proper inflation pressure should be selected from that range to match individual conditions. Lowing inflationpressure improves grip because the effective contact area is increased and there is a better tire cushioning effect.

If pressure is lowered too far, however, contact becomes uneven and driving is more difficult.


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Air pressure setting

contact shape

contact pressure

contact area

Tire stiffens

(Suspension effect)

The best way is for each individual to determine the regular inflation pressure for there situation. 16 psi can beconsidered a good starting point for both front and rear tires. Drive for a while with the tire inflated to this

pressure and then change inflation pressure from 1-3 psi until you find the inflation pressure you think is best.

SLICK SL - Compound and construction provides firm grip and excellent wear resistance.

SLICK HIGH GRIP - Compound and construction provide excellent grip. Chart below shows one

manufacturers information on compounds and construction. Generally soft compounds are used on colder days

and short races when maximum grip is desired with minimum warm up. Hot days and long races dictate harder

compounds.

DBC/DBH/RH2:Hard compound which offers excellent

wear and heat resistance.

DBM:

Hard compound suitable for medium-

to-

high road surfaces and medium andhigh temperatures

DBS:Medium compound suitable for low-to-medium- road surfaces and to low-to-

medium temperatures.

DBW:Ultra soft compound suitable for low-

dirt surfaces and low temperatures.


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RAIN - Knobby or treadded patterns in soft compounds give excellent performance and optimizes wet grip and

maximizes water drainage. Rain tires will wear fast on dry hot surfaces.

More information on Tires

http://www.kartweb.com/TechArt/Chassis/KartTires.htm

http://www.russellkarting.com/settings.htm

Wheel Components

Hub Rim Tires

Figure 34

Tires are mounted on rims. Rim size and width is selected based on the tire being used. Rim width can help tominimize or increase side wall flex that effects how a tire sets while cornering and how it expands at speed.

(Paragraph about selecting rims)Rims are made of various materials the most popular is aluminum. Rims can beeither bolt on or of the integral hub type.

The hubs are the part that attached the wheel to the ends of the axle. On live rear axle racers the hubs are keyedand either compressed or nutted to attach them to the shaft.Front hubs and hubs on dead axle racers include bearings which allow them to roll freely on the axle. Bearingsmust be of the precision type and be checked to insure they have the load capability demanded by the heavier evracer. Bearings can be sealed or lube type and must be properly adjusted and kept clean and lubricated to keepfriction as low as possible.Bolted hubs as shown above consist of threaded studs which the rims are fitted over and the secured. Hubmaterial selection is based on loading, weight and cost. Steel and aluminum are the most popular material thoughcomposites and plastics are making inroads in the sport.

It is important that a retaining pin be provided to insure the hubs do not slide off during operation. A loose wheelis dangerous and must be avoided at all cost.
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Figure 35 Figure 36

AXLE

The rear axle is the main part of the rear end. Mounted on it are the rear wheel hubs, brake rotor, sprocket andsprocket carrier, and the 3 bearings in their cassettes. Most components on the rear axle are held on by set screws,keys, or a combination of the two. To attach most components to the rear axle the components that are towards theoutside must come off first. For example if the brake rotor needed to be changed the bearing on the side and thewheel hub on that side would have to be removed and the brake rotor slid on first followed by the bearing and thenthe wheel hub. Plan for this when changing components on the rear axle. The components on the axe from theinside out are the Brake rotor on one side and then 2 bearings on the other, then the bearing on the brake side withthe sprocket carrier on the other, finally the wheel hubs are at either end.

Once on the axle the components can be maneuvered into alignment without taking off the other components.When aligning the components it is extremely important to ensure that components like the sprocket and brakerotor are perfectly aligned left to right and at a 90 degree angle to prevent uneven brake wear and to prevent chainbinding. Either of these conditions can cause inefficiencies, heat generation, and premature component failure and

wear. Once all of the components are on the rear axle it can be mounted to the frame. The bearing cassettes are thepoints of contact. Each cassette has 3 bolt holes in it that line up with the holes in the cassette holders on the racer.These bolt holes use 6mm head Allen bolts with a special tapered head along with a special tapered washer thatallow the bolt to fit snugly in the cassette and holder. DO NOT LOSE these bolts and washers they are not commonand are expensive to replace. To mount the axle simply line up the bearing cassettes on the axle to match those onthe racer. Place the axle on the racer and insert each bolt. Do not tighten the bolts until all of them are started intheir respective holes. Then tighten each bolt a little more until all are in. This will prevent binding andmisalignment which can be very frustrating. That is how you put together the rear end.

BEARING HOLDERS

They are 3 protrusions on the back of the frame and have slots for the axel and holes for the bearing cassettes.There are 2 on the motor side and 1 on the brake side. Any hole in the tubular frame must be plugged for the safetyof the track workers.


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CHAPTER 6 MECHANICAL DRIVE TRAIN

The mechanical drive train provides the connection from the motor output shaft and the drive wheel. The

driveline typically provides some mechanical advantage to match the motor power curve to the application.

The mechanical drive train is often the last system to be considered when building a racer. Selection of optimizedcomponents using engineering principles is just as often overlooked. It is a mistake to simply apply thecomponents that are typically used for engine driven racers on an electric vehicle. The high torque capability ofan electric motor and the increased weight of an electric vehicle can quickly destroy a drive train that works wellon a so called high power shifter kart. Be sure to apply manufacturers data to the system design. Terms listed inadvertising like high quality, strongest available, high tensile mean nothing without numbers and units to backthem up. If a vendor cannot supply the information you need, move on. If you are in doubt as to what a part cando, test it. Areas that can be reserached or tested are: Torque, Power, Speed, Over Load capability, Chains, Belts,and Gear boxes

OPEN DRIVE (CHAIN) GUARD

The specifications require that open mechanical drives has a guard to protect anyone from incidentally contacting a

moving part.

Chain Guards

MOTOR MOUNT BRACKETThis component is a more traditional racer component that allows the motor assembly to be attached to the frameof the racer. One common design has a flat top plate that offers a solid platform to attach the motor assembly. Onthe bottom it has to groves that run the length of it allowing it to sit in the tubes of the racer frame. Two smallerpieces with circular groves secure the flat component to the frame. Because the bolts that attach the Motor Plate tothe Motor Mount end up being directly below the motor, it is important to attach the Motor Plate to the MotorMount before installing the motor. Other methods may be used but it is important that your design securely fastens


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the motor to the frame of the racer. A jack bolt is necessary to keep your mount position and the chain tight. Tubecoilers also will work. The motor torque will cause the motor to shift and the chain will begin to jump.

MOTOR MOUNT

The motor mount is a custom build face mounting system that mounts to the motor on the side with the drive shaftIt should have bolt holes that align with the pattern on the motor and a circular hole in the center for the driveshaft to come through. On the bottom it should have holes that line up with the motor plate. Steel should be used toensure that the mount will hold up to the strain of the motor.

Figure 37 Brackets Figure 38 Motor mount bracket


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CHAPTER 7 ELECTRICAL SYSTEMS

Traction Power System

As the name suggests, the ev racer is equipped with an electric drive system. This system is sometimes called thetraction power system. Its purpose is to develop the mechanical power that propels the racer down the track. Thesystem is made up of three main components, motor, controller and battery. As this racing series requires an all-electric drive, batteries are needed to supply power to the controller which meters and conditions the power to themotor based on driver input.

According to the specifications, the traction drive power system must not exceed 14kW peak(18.74HP peak) at any time during the race. The system may use any combination of battery instantaneous voltageand instantaneous current, as long as product of volts and amps never exceeds 14kW as measured in the input of

the motor controller. In addition, the racer is only allowed to use 8640 Watt-hours per race. This is measured atthe battery pack terminals. Selection of the electric drive components should be made with this in mind. There islittle to no benefit gained from carrying a heavy extra-large motor or controller that you cannot use. Specifying toosmall a motor or controller will result in poor performance and premature component failure.

Driver In ut


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Chapter 8 Battery

BATTERY SELECTION

Ideally, batteries should store as much energy as possible in a given volume to achieve a long operating range, havethe lowest weight possible to reduce the load on the drive system, and perform well through manycharge/discharge cycles over the life of the battery. Much consideration needs to be put into the selection of thebattery or energy source for the eV racer. Likely to be the most expensive component it is prudent to know how itworks, and how to charge and service it to get the most performance and life. Batteries are electro chemicaldevices used to store electrical energy and deliver power on demand to an electric circuit. The basicelectrochemical unit is a cell. A batterys cell consists of four major components: 2 electrodes (anode andcathode), seperators, and the electrolyte. These parts are contained in a case/enclosure. The enclosure shape andsize varies with capacity and application. During discharge, the negative or anode readily gives up its surpluselectrons, while the positive electrode or cathode accepts these electrons. This process is reversed when thebattery is charged. The external circuit containing the controller and motor creates a pathway for the electrons to

flow or the load for the battery. The electrolyte provides a pathway for positive ions to pass between the cathodeand anode. The separator is the divider which keeps the cathode and anode portions of the cell insulated from oneanother.

BATTERY CHEMISTRY

Chemistry determines if a cell is a primary or secondary type. Primary cells similar to conventional alkalineflashlight batteries are one time use and are removed and recycled. Secondary cells can be used and recharged anumber of times. Secondary cells are the type typically found in modern electric vehicle use.

The chemical makeup of the cell, specifically the anode and the cathode determine the electromotive force orvoltage of the cell. Battery manufactures formulate the materials to optimize power and storage capability andoperating life. A lead acid cell develops 2 volts (nominally); NiMh develops 1.2 volts and Lithium Cells 3.2-3.7 voltsVoltage is a measure of the electromotive force (EMF) needed to push the electrons through the circuit. Thehigher the voltage a cell develops, the fewer cells are needed to be connected in series to meet the applicationsrequired battery voltage. A 12 volt lead acid battery has six cells where a 12 volt Lithium battery will have three orfour cells in series. The voltage of a battery pack for EVGrand Prix competition may not exceed 72 nominal volts.


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When one or more cells are assembled together they form a battery. This is done to add additional storage capacitymeasured in amphrs or raise the electromotive force (EMF) measured in volts or increase the power.

PACK VOLTAGE

The best pack voltage is determined based on the motor and controller you select and what capacity battery cells

are available to you within the vehicle specifications and within your budget. The ideal pack voltage is acompromise. Weight of a pack is also a consideration. Some people believe that the weight of a high voltage packis less because smaller wires can be used to carry the same power. This may be a misnomer since you need moreintercell connectors and non-power producing hardware and containers which need to be considered.

CAPACITY RATING

A cell or battery stores electrical energy by storing a charge which can be delivered across a potential difference(voltage) between its terminals. So it stores charge and does work when that charge is delivered across a voltage.This is in line with energy being equal to voltage times charge.The convention is to quantify the capacity of a cell or battery in terms of charge and it is called C. Also convention

is to have a standard discharge time for C. This standard time is 20 hours. The basic unit of electric charge is theCoulomb which is equal to one ampere for one second (As) the size of batteries of interest here will use Amperehours (Ah) as charge units. One Ah = 3600 As or 3600 coulombs. A battery rated at 20 Ah can deliver its entirecharge in 20 hours at a rate of one ampere. 20h * 1A = 20Ah.

The term C rate is used to normalize discharge rated for batteries of different capacities. In the example above, C= 20Ah. The discharge rate (C rate) is C/20 = 1A. If the capacity was 50Ah, a C rate of C/20 would equal 2.5A. Ifthe current was 150A from the 50Ah battery, the C rate = 3C.

The capacity of the battery can vary depending on the C rate. The higher the C rate, the less charge can beextracted from a battery and the less work it will do. This is described by what is called the Peurkert Effect. It isquite dramatic with lead acid chemistry but much less so with Lithium. Charge and charge ratings for batteries are

independent of voltage. The cells or batterys voltage will vary due to the internal resistance of the cell. Theterminal voltage is equal to the open circuit voltage minus the internal resistance times the current. Vterm = Vo.c. I * Rint. This becomes a large factor when running batteries at high power. Low internal resistance is requiredfor high peak power. The internal resistance is also the mechanism for battery heat (I^2*R loss). Battery voltagewill also change with regard to state of charge (SOC). As the cell or battery discharges, the voltage will decrease.

Actually the relationship of battery (or cell) voltage and current is linear. V = Voc - Ri * I. Where V = actual batteryvoltage at the terminals, Voc = open circuit voltage, Ri = battery internal resistance and I = battery current. The


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