a new way to multi-task get your exercise in while you work! a bike-powered athena workstation 1.102...

A New Way to Multi-taskGet your exercise in while you work!

A Bike-Powered

Athena Workstation

1.102 Group D Piotr FidkowskiSebastian Figari

Sara JohnKendra Johnson

Julia KiberdTina Lai

Devon McCorkle

Why?

To create a feasible, interactive, and interesting energy harvesting system

To inform the public of renewable energy possibilities and to raise energy awareness

Something that meets and need an that people can fit into their everyday lives

What?

Bicycle-powered Laptop Retro-fitted

Recumbent Exercise Bike

Generator/Motor Data Acquisition

Device Laptop

How?

Convert the rotational energy of the exercise bike into electrical energy through a generator or motor

Use that power to run a laptop that will be secured to an adjustable table, fitted to the bicycle

Gearing between the flywheels and the generator to ramp up the RPM

Power Production

Average Person produces 60-100W @ continuous 63rpm

Pedal Power 50% efficiencyLaptop uses 19.5V adapter, 130W max

chargerLaptop consumes on order of 30W

average

Specifications: Mechanical Components

52 tooth gear for pedal shaft

22 tooth freewheel 6 inch camshaft pulley for

flywheel shaft Retro-fitted tensioner for

chain 2.5 inch camshaft pulley

for generator Bike chain Adjustable table IS&T security device

Specifications: Electrical Components

10 amp DC generator 12 volt lead acid battery Xantrex charge controller Brushless 12 volts DC fan Resistor Power monitor Dell Latitude D820

Laptop Power cord

Specifications: Fabricated Components

.5 inch plywood (15” by 15”) base for electrical components

3/4” mfb for electrical housing

Plexiglass for display Acrylic boxes for housing 1/4” aluminum for

generator plate 3/16” metal disc for gear

mounting

Specifications: Retro-fitting

Cut down and bolt on front gear

Remove belt drive system and magnetic resistance mechanism

Modify belt pulley to attach 22 freewheel to axis

Attach camshaft pulley to drive generator (bolt to flywheel)

Specifications: Power Generation

Initial Capacitor Buck converter

95% efficiency Feedback on current to

maintain charging rate PWM sets duty cycle,

which sets charging rate, which sets resistance to biker

PWM adjustable Second Capacitor 12V Lead-Acid battery

Modifications To Original Design

Mechanical: Mounting generator Pulleys instead of gears Welded table onto bike Plexiglass cutout in

casing Chain tensioner

Electrical: LabJack Circuitry Housing

Assembly

1. Remove bike housing, resistance mechanism, drive belt system

2. Attach 53 tooth gear to pedal shaft by removing plastic belt gear, machining aluminum plate, and bolting gear to plate

3. Use lathe to modify flywheel drive pulley to receive threaded freewheel

4. Drill/tap four holes in flywheel to attach 6” camshaft pulley

Assembly (Continued)

5. Attach flywheel with attached components to bicycle and thread camshaft belt and bicycle chain over axis

6. Fabricate generator mounting plate and bolt to bicycle frame

7. Fasten 2.5” camshaft pulley to generator8. Adjust horizontal location of flywheel axis to

obtain proper belt tension9. Modify scrap derailer to tension chain, attach

by bolting to flywheel mount

Design Process

Brainstorm, research, surveys Initial ideas, broad research, in-field surveys

Calculations and more in depth research Specific parts Analysis of similar projects

Fabrication and adjustments Prototyping and testing merged into fabrication

due to time constraints

Deployment and evaluated public response

Public Response

LOTS of interest Minor lack of use due to

embarrassment Tim Moore (manager of

Zesiger Center) expressed interest in permanent installation and display

Public education of sustainable energy

(below) Steve, Kendra, Dr. G, and Julia are all really excited about sustainable energy

Evaluation of Main Project

Larger time span would have been optimal Could make it a two-semester project Lack of time led to hasty production

Clearer instructions, expectations, and a set timeline Order parts earlier; led to too much downtime

Good way to experience the design process Better understanding of sustainability, energy,

and energy storage Great!

Our Group

(left to right) Sara, Piotr, Julia, Sebastian, Kendra, Tina and Devon

Evaluation of Class

Fewer electricity labsSplit lab times

Offer Tuesday/Wednesday labsRube Goldberg machine was very helpful

Boosted confidence in our building abilities Better understanding of how parts create a

wholeMore welding Helpful and knowledgeable instructors