Design Team: Andrew Yanoshek - Electrical Engineering Holly Carlier – Mechanical Engineering Jake Gendron – Mechanical Engineering Marshall Taylor – Electrical

Design Team:Andrew Yanoshek - Electrical Engineering

Holly Carlier – Mechanical EngineeringJake Gendron – Mechanical EngineeringMarshall Taylor – Electrical EngineeringNathan Brand – Mechanical Engineering

Sponsors:Greg Donohoe

Ivus Energy Innovations

Problem:Riding scooters up hill sucksCurrent kick scooter designs are exhausting to ride up hills. Electric scooters are heavy, expensive, and require battery charging.

Goal:To design and build a lightweight electric kick scooter. The vehicle will incorporate regenerative braking and ultra-capacitors to provide power assisted riding without charging batteries.

Nov 1-30:

•(In Process!) Conceptual Design Review• (Done!) Solid Model Scooter• (Done!) Purchase motor gearing devices• (Done!) Construct Initial Prototype• Plan electrical motor components

Dec 1-18:

•Test initial prototype•Write end of semester report•Update Website•Research Energy Storage Solutions

Sept 1-15:

• (Done!) Interview Client• (Done!) Discover Prior Art• (Done!) Project Learning Tasks

Sept 16-30:

• (Done!) Test Scooter • (Done!) Develop Requirements • (Done!) Scooter Testing Day

Oct 1-15:

• (Done!) Snapshot Day • (Done!) Define Initial Specs • (Done!) Purchase Scooter• (Done!) Purchase Motor • (Done!) Brainstorm Solutions which meet

functionality

Oct 15-31:

• (Done!) Compare solution paths • (Done!) Select two or three design paths for

further pursuit

Jan 1-31:• Continue Research in Ultracapacitors and

Alternate Motor Options• Test Power Usage and Generation of Motors

Using Rolling PrototypeFeb 1-28:• Finalize a Motor Choice• Finalize Motor Mount Design• Decide on Control SystemMar 1-31:• Start Fabrication of Final PrototypeApr 1-30:• Prototype Testing• Improve Design• Prepare For Design Review and End of Year

Wants:• Looks ‘cool’• Minimize human effort• Alternate charging

methods• Weigh <15 lbs• Braking system does

not damage scooter• Comfortable• Quiet

Needs:• Last mile transportation• Light weight• Convenient• Equal amount of effort to

go up hill as on flat ground

• Pleasant to ride• Low cost• Emergency brake• Hold average person• Off power grid

Purpose: Compare existing scootersUnderstand power needsQuantify Fun

Conclusions:Typical Speed: 4 - 7 (mph)

Braking Power: 80-160 (Watt)

Kick Energy: .03 - .07 (Watt*hour)

Kick Power, Flat Ground: 12-30 (Watt)

Kick Power, Hill: 100-160 (Watt)

Observation: Power output varies linearly with weight

Drag Coefficients:

Xootr, straight rolling: .009

GoPed, straight rolling: .018

• Total Cost <$1000• Assisted Flat Ground Range: > .1 Miles• Maximum Rider Weight: = 250 Pounds• System Efficiency: >50%• Energy Storage Capacity: >1.8 W*h• Total Scooter Weight: <20 Pounds• Sustainable Power Output: 120W

Rolling Prototype• Purpose is to have a

test platform that helps us find: • Input power

required• Size of capacitor or

battery• How the ride feels• Unforeseen

problems

Final Prototype• Goal is to have a

working prototype which allows us to achieve:• Highest possible

efficiency• Easy to use human

interface• Fun to ride

prototype

Mechanical•Frame•GearingElectro- Mechanical•Motor/Positioning•Throttle/ BrakeElectrical•HID•Controller•Power Transfer•Energy Storage

Mechanical•Frame•GearingElectro- Mechanical•Motor/Positioning•BrakeElectrical•HID•Controller•Power Transfer•Energy StorageRisks

Possibilities - Issues

• Xootr – (Wheel damaging front

brakes, collapsible shaft)

• Go-Ped – (High rolling resistance, hard

to modify, PITA folding mech.)

• Adult Razor – (Hard to modify, small, ugly)

SelectionXOOTR!• Best Folding Mechanism.• Wooden Modifiable Deck.• Low Rolling Resistance!• $200


Needs:• 8-1 Gear Ratio• High Efficiency• High Torque • Low Cost• Easy Modification• Durable

Selection:• Chain and Sprockets• ~8-1 Gear Ratio• 1/4th inch Pitch Diameter

Chain• 76, 63, 12, and 9 teeth

sized sprockets

Options:• Bevel Gears• Spur Gears• Planetary Gears• Chain and Sprockets• Belt and Pulleys


Needs:• 120W Mechanical Output• High Efficiency• High Torque • Easy Mounting & Connection

Selection:• BLDC (Outrunner)• 300W rated electrical power• Requires complex controller• >85% Peak efficiency

Options:• 3 Phase• DC (2 phase, brushed)• Brushless Direct Current

(BLDC)


Front Wheel Pros:• Shifts center of gravity

forward• May aid in steering when

boosting• Easy to Wire

Cons:• May reduce control when

regen is active• Mounting difficult• May reduce ability to turn

Rear Wheel Pros:• Easy attachment• Easy to Gear• Out of the way• Does not affect folding

Cons:• Takes up deck space• Difficult to wire

(comparatively)• May impede stomp brake


Needs:• Stop Wheel• Dissipate Heat• Reliable Operation • Low Cost• Durable

Selection:• Fender/Stomp Brake• 1 Moving Part• Reliable Operation• Existing on Xootr

Options:• Disk Brake• Caliper & Wheel Brake• Fender/Stomp Brake• Front Wheel Wedge Brake



Functions:• To Engage

Regenerative BrakingOptions:– Variable Hand Brake– Push Button– Switch

• Throttle SystemOptions:– Push Button To Engage Motor– Handle Throttle For Variable Speed– Knob Or Toggle For Variable Speed

• Visual For Showing Energy Storage LevelsOptions:– LEDs– Gage


Option Pros Cons Recommendation

Discrete analog system SimpleQuick prototyping

BulkyLimited functionality

Use for prototyping / low level controls

3 phase BLDC ASIC Package solution to 3 phase drive

Constrained by designFunctionality Rarely regen-ready

Investigate pending motor selection

Micro-Controller (MSP430)

Highly flexibleprogrammable

Does nothing until powered and resetTime intensive to prototype

Develop for final prototype

Inquire to IVUS Learn what professionals have done

Planned


Switches power direction and limits current

Option Pros Cons Recommendation

Buck converter EfficientSimple

Only steps down Good for some final functions

Forward converter Efficient Transformer basedComplicated

Investigate

555 pulse width generator

CheapEasy

Hard to control Use for testing

Transformer SimpleEasy

ExpensiveHeavy

Use for testing

Relay CheapEasy

BinarySlow

Use for testing

H-bridge 3 phase drive

EfficientHighly controllable

ComplicatedRequires controllerRequired for BLDC

Build simple test circuit to select final motor


UltracapacitorsPros:• High Power Density• Fast Recharge Rate• Light Weight• Long Usable Life

Cons:• Expensive Energy Storage• Low Max Voltage• Damaged If Charged Incorrectly

BatteryPros:• Higher Energy Storage• Low Cost

Cons:• Low Power Density • Heavy• Slow Recharge Rate



• 3-Phase brushless motor• Controller (programmable)• Energy storage in capacitors• Hub motor

• Rolling Prototype• Multiple solutions in parallel• Borrowed/recycled parts for prototype

Possible Failure Points

Risk Alleviation

Rolling Prototype• Purpose is to have a

test platform that helps us find: • Input power

required• Size of capacitor or

battery• How the ride feels• Unforeseen

problems

Final Prototype• Goal is to have a

working prototype which allows us to achieve:• Highest possible

efficiency• Easy to use human

interface• Fun to ride

prototype

• Explore design options• Fully functional prototype scooter–Drivable with working

regeneration• Future team preparation

• Work with Art & Architecture Students

• Work with Business Students• Mass Production

Recommendations

Current Purchases• Scooter - $210• Motor - $39• Chain - $20• Sprockets - $50• Machine Shop - $100

Future Purchases Estimates• Electronics Parts - $400 • Controller Units - $150 • Ultracapacitors - $80 Per Capacitor

(approximately 8)• Machine Shop - $300

Total: $1909.00

Documents

Design Team: Andrew Yanoshek - Electrical Engineering Holly Carlier – Mechanical Engineering Jake Gendron – Mechanical Engineering Marshall Taylor – Electrical