Proposal for 2013-2014 FSAE Global

Engineering Competition

Authors: Ben Brownell, Josh Guion, Tom Beaulieu, Steve DeSantis, Ryan Bonin,

Randy Carlson, Pete Konstatilakis, Jeff Cahill, Tucker Berube, Matt Dolan,

Joe Bleczinski, Nick Elliot , Stephen Miller, Yigit Tokbey, Brad Thompson

11/1/2013

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Contents

1 Abstract ................................................................................................................................................. 1

2 Introduction ........................................................................................................................................... 1

3 Competition ........................................................................................................................................... 2

4 Design of Car #37 ................................................................................................................................. 3

4.1 Aerodynamics ............................................................................................................................... 3

4.2 Controls ......................................................................................................................................... 3

4.3 Frame ............................................................................................................................................ 5

4.4 Electronics ..................................................................................................................................... 6

4.5 Engineering Drawings................................................................................................................... 6

4.6 Powertrain ..................................................................................................................................... 7

4.7 Suspension .................................................................................................................................... 9

5 Budget Analysis .................................................................................................................................. 10

6 Conclusion .......................................................................................................................................... 10

References ................................................................................................................................................... 11

Figures

Figure 1: Pedal assembly .............................................................................................................................. 4

Figure 2: Brake rotor and caliper assembly .................................................................................................. 4

Figure 3: Pneumatic shifting assembly ......................................................................................................... 4

Figure 4: Current 2013 - 2014 prototype engine box of the frame ............................................................... 5

Figure 5: Full intake assembly ...................................................................................................................... 8

Figure 6: Intake Plenum velocity profile: inlet flow 17.8 m/s (40 mph) ...................................................... 8

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1 Abstract

The 2013-2014 University of New Hampshire (UNH) Formula SAE (FSAE) project concerns

design, development, and global competition of a scaled Formula One race car. The car is to be

designed with respect to individuals considered as a non-professional weekend racer for Formula

One style racing. During all times, the car will be designed and created within specifications

stated by the Society of Automotive Engineers (SAE). Any resulting divergence from the

presented rules could result in expulsion from the competition or deduction of points during

competition. The global competition for FSAE will be held during the second week of May in

Brooklyn, Michigan. Improving on the design of the past nine FSAE Cars, the current model,

Car #37, will be developed in regards to positive attributes of previous models and new design

ideas of the current team. Presented in the following report are detailed changes for the tenth

installment of UNH's car for: Suspension, Frame, Power Train, Controls, Electronics and

Aerodynamics. Also, the budget for Car #37 will be discussed in relation to the previously stated

subgroups.

2 Introduction

The FSAE global engineering competition concerns the design and construction of a

miniaturized Formula One race car. Said car is to be designed and built by students at all times

with minimal involvement from members of industry. The car is to adhere to the presented FSAE

rules of 2014 for each subgroup of the car; Suspension, Frame, Power Train, Controls,

Electronics and Aerodynamics. Due to the extensiveness of the rules for the previously stated

subcategories, the full rules may be found on www:unh:edu/fsae.

The members for the 2013-2014 season include fourteen mechanical engineering students: Ben

Brownell, Josh Guion, Tom Beaulieu, Steve DeSantis, Stephen Miller, Yigit Tokbey, Brad

Thompson, Ryan Bonin, Randy Carlson, Pete Konstatilakis, Tucker Berube, Matt Dolan, Joe

Bleczinski, Nick Elliot. The final member of the team is electrical engineering student Jeff

Cahill. The development of the race car for the 2013-2014 race season will be the eleventh year

of competition for the University of New Hampshire. In consideration to the previous car

designs, the car for the current season will improve upon past accomplishments while integrating

new designs.

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3 Competition

The global competition is divided into static and dynamic events with each team receiving a

point score based upon performance of the car. The static event categories are Technical

Inspection, Marketing Presentation, Engineering Design, and Cost Report. Technical Inspection

must be passed by the automobile in order for the car/team to compete. Within the inspection

process, various components including the frame as well as safety features will be tested. The

design presentation event relates to the team members description of design for the race car.

Individual members will present the respective sub group categories to judges (members of

engineering industry), and said categories will be rated on point scales. Within the Engineering

Design event, the car will be judged on how well the automobile meets the intent of the market

and the engineering sort of the car. Lastly, the Cost Report will be judged on how efficiently

funds were utilized in regards to design matrices for the vehicle. The dynamic events of

competition include Acceleration, brake test, Skid-Pad Test, Autocross, Fuel Efficiency, and

Endurance. The general goal of the dynamic competition is to maintain the mechanical integrity

of the vehicle at all times. The Acceleration test will measure the car's ability to travel along a

straight path for approximately eighty-two yards. The brake test is to ensure the car's four brakes

will fully stop at a provided speed. The Skid-Pad event measures the car's cornering ability on a

flat surface. During the Autocross event, the car will be measured for maneuverability and

handling for a predesigned course. Lastly Fuel Efficiency and Endurance events concern

measurement of fuel usage for the car during a 13.66 mile race track. During the events, the car

and driver will experience other additional drivers on the course, and as such will have to adapt

to changing conditions during competition.

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4 Design of Car #37

4.1 Aerodynamics

The Aerodynamics package will have four key components: Nose Cone/Body, Side Pods,

Diffuser, and Front/Rear Wings. The overall goals are to reduce drag and increase down force

with the aim of reducing overall lap times. The Nose Cone will enclose the frame and impact

attenuator. Its functions compared to last year’s car will also be to reduce the amount drag and

promote laminar flow over the body of the car. The side pods will be designed with three main

goals in mind. The first goal of the side pods is to promote laminar flow along the side of the

vehicle and over the wheels. Second, the side pods will be designed to direct flow coming out of

the vents of the side pods at the air intake along the left side of the car. Third, the side pods will

be large enough to house the radiator.

The Diffuser will be on the underside of the frame and also act as the floor of the car. Utilizing

Bernoulli’s principle the Diffuser will create an area of low pressure underneath the car, resulting

in increased down force on the car. In addition to the Diffuser the aerodynamics team will be

studying the feasibility of implementing front and rear wings on the car. The advantage of the

front and rear wings are increased down force on the car and the front wing will cut down on the

drag produced by the front tires. By implementing vortices blockers the amount of induced drag

created will be minimal resulting in a better overall lift to drag ratio.

4.2 Controls

Control system of Car 37 will include major changes to the shifting mechanics of the car and the

pedal system. The car will incorporate paddle shifters along with the previous car’s “bump” or

stick shifter. Changing the design of the shifter will allow the driver to maintain constant control

of the steering wheel while shifting the gears of the engine, and maintaining a backup for

reliability. This change compares to the previous design in which the driver has to remove

his/her hand from the wheel and shift, which meant the driver may not have complete control of

the car while changing gears. Also, the pedal designs of last year’s car did not allow the driver

to have effectively implement heel-toe downshifting techniques and overall ergonomics were

poor. Car 37’s design is to incorporate a different adjustable pedal design and to maintain the use

of a nonlinear throttle body, which will allow more control over the lower end of the RPM range.

To improve the overall ergonomics of the vehicle, a non-slip pedal design will be incorporated to

increase driver safety and usability.

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Figure 1: Pedal assembly from 2013’s Car 49 with the master cylinders mounted under the frame

To reduce weight, the steering column and tie rods material will be changed to carbon fiber. To

increase reliability controls will change from drilled rotors to slotted rotors. This will aid in the

cooling and performance of the brake system as the slots will push high temperature brake dust

and gases out to the atmosphere.

Figure 2: Brake rotor and caliper assembly

showing the slotted rotor design to aid in

reliability and performance

Figure 3: Pneumatic shifting assembly

showing the CO2 tanks, regulator, solenoids

and air cylinder

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4.3 Frame

The frame of Car 37 incorporates several new changes in design in correlation to suspension,

drivetrain, controls and structural tube optimization. The frame as a whole is being analyzed for

the center of gravity, structural rigidity, weight and comfort of both the 5th

percentile female and

95th

percentile male. The engine box is being redesigned for the single cylinder engine and

internal differential as well as a new impact attenuator for the front. The goal is to improve the

structural rigidity from previous year’s cars while maintaining the weight with the new changes.

The following figure shows some of the changes for the prototype design.

Figure 4: Current 2013 - 2014 prototype engine box of the frame

The major change to the frame is the engine and suspension boxes as seen in figure 1. Previous

frames were designed around the use of a four cylinder engine which has been swapped out for a

single cylinder engine. The suspension rails are also parallel to each other to simplify the

suspension geometry and allow for a change to push rods and incorporation of a sway bar.

The impact attenuator in previous years was seven layers of aluminum honeycomb epoxied

together. This year a SAE certified foam impact attenuator will be used. This IA weighs less

than the aluminum one and is more cost effective. The new foam IA will not need to be crush

tested as it will be performed and certified by SAE which saves money on crush testing.

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4.4 Electronics

The electronics team will be responsible for the custom dashboard, data acquisition, and general

wiring. The custom dashboard will display vital data to the driver of the vehicle to instill driver

awareness on the track as well as aid in decision making. The display will be made of high

current LEDs to ensure that the driver will be able to see them in sunlight and during vibration

caused by the engine and other moving parts. Another possibility to be considered if it will fit

within the budget is an LED screen which can display more complex graphics; however this

complexity may not be necessary. The screen will read data fed from a microcontroller which

will receive its data serially from the Vehicle Engine Management System (VEMS). The VEMS

is the unit which controls the engine and collects data from all of the sensors. These various

sensors for pressures, temperatures, compressions, and ratios will need to be arranged on the

vehicle in a way such that they will avoid interfering with moving parts. They will also have to

be installed so they can avoid damage during driving, be weatherproof, and resistant to vibrations

of the car. The data collected by the sensors will also be transmitted wirelessly from the VEMS

and be sent to a computer to be graphed and analyzed. Everything will also have to be fused and

grounded appropriately according to the 2014 Formula SAE Rulebook.

4.5 Engineering Drawings

A significant improvement to the 2013-2014 UNH Precision Racing Team is to incorporate

engineering organization. In industry, manufacturing companies have an archive of engineering

drawings of all parts that are machined either by the company or outsourced to a third party. The

drawings have all necessary dimensions to be machined, tolerances, special notes, part name and

number, and company information. When changes are made to a part, a drawing revision is

made and becomes the new control document while the old revision is transferred to an old

drawing archive. This same process will be adopted by the team to make for a more organized

and professional experience.

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4.6 Powertrain

The 2013-2014 FSAE car 37 will be utilizing the same powertrain as last year, a single cylinder

YFZ 450R four stroke engine with a 5 speed manual transmission. Due to the unknown history

of the motor when it was purchased, a complete overhaul will be done. Each component within

the motor will be gone over and replaced if necessary. The stock cast piston and rings will be

replaced with an aftermarket high performance forged piece. This will increase the compression

ratio, allowing the use of 100 octane fuel that will produce more horsepower. If our funds allow

for it, a high performance head paired with more aggressive intake and exhaust cams will be

installed. To reduce weight and improve the cars design aspects, a custom carbon fiber muffler

will be fabricated. Last year’s car also had an issue with the oil overflow (catch-cans) filling up,

this was due to mounting them too low in relation to the motor. They will be replaced with

custom fabricated clear containers made from high-temp Plexiglas tubes, mounted in the correct

location.

The intake plenum for the 2013-2014 car 37 will be designed around three main parameters in

order to overcome the 20mm air intake restriction: ram air induction, swirling air to fuel mixture,

and an optimized runner length to utilize Helmholtz frequency generated from the engine. Ram

air induction will consist of relocating the throttle body of the intake to the left side of the car

rather than pointing straight up like car 49 (2012-2013). Having the throttle body on the side of

the car, pointed parallel to the front of the car, will allow air streaming of the side pods to be

directed into the throttle body. This means that the faster the car is traveling the, the more air that

will be forced into the plenum through the 20mm restrictor. Providing enough air to the engine is

one of the biggest obstacles for powertrain, so switching to a ram air induction style intake will

ease the flow of air into the plenum for increased power and throttle response. The runner will

also be able to be the proper length to match the Helmholtz frequency of the power band of the

engine to create a surge of frequency carried air to further maximize power output.

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Figure 5: Full intake assembly to show optimized intake runner length from Helmholtz equation and optimum fuel

injection

The second parameter that the intake will be based on is swirling the air before the fuel injection

to provide a higher amount of mixing of the air and fuel before it enters the combustion chamber

of the engine. The better the fuel is mixed evenly throughout the piston in the cylinder, the more

efficiently the combustion cycle, and therefore providing more power and efficiency throughout

the rpm range. The swirling air also reduces the friction on the sidewalls of the plenum, allowing

for easier flow into the cylinder for the max amount of air.

Figure 6: Intake Plenum velocity profile: inlet flow 17.8 m/s (40 mph)

Power from the engine is transferred to the rear axle via two sprockets and a chain. These

sprockets need to be sized appropriately as to allow for the lightest rotating weight and the most

ideal reduction ratio. The driving/driven sprocket ratio on last year's car was not ideal, resulting

in the car's top speed not being high enough. To optimize the ratio for this year's car, a Matlab

program was written relating sprocket ratio, tire diameter, speed over ground, and other

parameters. Using this program, the ideal sprocket sizes were determined to be 13 teeth (down

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from 14) for the driving sprocket and 34 teeth (down from 52) for the driven sprocket. As the

year progresses and parameters of the car change, the parameters can be modified in the Matlab

program to optimize the ratios further.

For this year we’re using a Taylor Racing limited slip differential in the rear of the car giving it

independent rear axles. The Taylor Racing differential we’ll be using is one used in last year’s

car that will be sent out and rebuilt by Taylor Racing. Looking in to new LSD prices ranged from

$2,500 and up where sending this one to be rebuilt correctly by the manufacturer will only cost

approximately $250. The differential carrier will be designed to be adjustable again in order to

allow movement of the differential to tighten the chain on the sprockets. The carrier will also be

mounted inside the rear frame box unlike previous years in order to simplify suspension points

and lessen the angle of the rear axels.

4.7 Suspension

The major design improvement to car #37 for the suspension system entails of switching to a

push-rod and sway bar system in both the front and rear and of the car. This will allow the car to

enter turns faster with less body roll resulting in faster lap times. To account for these changes,

new components will be designed. These components must be durable to withstand the stresses

seen by high cornering speeds, but must also be lightweight to help reach our goal of a 400lb

vehicle. To do this we will be focusing on designing lightweight uprights/bell-cranks and

switching to carbon fiber A-arms.

The uprights need to be redesigned to account for the new push rod configuration that will

actuate the shocks and sway bar in both the front and rear end of the car. Shedding weight from

these uprights in the front and rear suspension is a goal to help decrease the overall weight of the

car. This will be done by decreasing the factor of safety in the uprights from about 300 (current)

to around 5 (proposed) which will decrease the weight significantly. To also decrease weight, a

new wheel center design is also being considered. This will be done to decrease the weight of the

current wheel design, but also to provide a better cosmetic appearance.

To reach our goal of 400lbs, we want to change the material for the A-arms and push rods from

steel to carbon-fiber. These components are currently made of steel. The objective of this is to

decrease the weight by 50%. There are two ways the carbon-fiber tubes can be made: protrude or

roll-wrapped. We are expecting to use the roll-wrapped design. This is a multi-directional fiber

alignment and tubes made this way, have excellent torsional strength, axial strength, and lateral

strength.

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5 Budget Analysis

In order to correctly build the car to previously mentioned parameters a budget of $45,000has

been estimated. Allocations of the finances are as follows: $10,000 for travel of the team;

$10,000 for the drive train system; $5,000 for the suspension, frame, electrical, aerodynamics;

$3,000 for the electrical system; and $2,000 for the brake system. In order to appropriate the

funds, sponsorship packets have been created and sent to local and national companies 2

previously affiliated with UNH. Previous sponsors have included Wilcox, Tucker Engineering,

BAE system, Whelen, and the College of Engineering and Physical Sciences. Current fund

raising efforts have gained the team approximately $22,000 in capital and materials. Fund raising

efforts will proceed for the remainder of the project in order to fulfill the remaining deficit in the

budget. The Gantt Chart displays the expected order of completion of tasks within the next eight

months for the project.

6 Conclusion

The development of Car #37 will work to improve upon past UNH FSAE cars as well as

incorporate new technical changes to the present model. Substantial changes for the suspension,

frame, power train, aerodynamics, controls and electronics of the car will allow for both decrease

weight of the car and increase maneuverability. The modifications will develop an overall more

competitive race car for the global engineering competition. Sponsorship for the proposed budget

of $45; 000 has begun with donations from several organizations and companies leading to a

current budget of approximately $22; 000. Additional fund raising efforts are to be continuous

throughout the remainder of the project to fulfill the monetary cost. Over the preceding months

the car will be designed and crafted within specifications set forth by the FSAE administration.

Current efforts have allow the race team to remain on schedule for the competition deadline of

May, 2014.

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References

[1] “SAE Collegiate Design Series: Formula SEA." System Dynamics. SAE Collegiate Design

Series: Formula SAE. N.p., n.d. Web. 30 Oct. 2013.

http://students.sae.org/competitions/formulaseries/.