Transcript Final presentation

A New Way to Multi-task
Get your exercise in while you work!
A Bike-Powered
Athena Workstation
1.102 Group D
Piotr Fidkowski
Sebastian Figari
Sara John
Kendra Johnson
Julia Kiberd
Tina 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% efficiency
Laptop uses 19.5V adapter, 130W max
charger
Laptop 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
Attach
camshaft
pulley to
drive
generator
(bolt to
flywheel)
Modify belt pulley to attach 22
freewheel to axis
Cut down
and bolt on
front gear
Remove belt drive
system and magnetic
resistance mechanism
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 generator
8. Adjust horizontal location of flywheel axis to
obtain proper belt tension
9. 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 labs
Split lab times
Offer Tuesday/Wednesday labs
Rube Goldberg machine was very helpful
Boosted confidence in our building abilities
Better understanding of how parts create a
whole
More welding
Helpful and knowledgeable instructors