Transcript Slide 1

Michael Erwin
Ross Martin (Team Leader)
Tao Nguyen
Clifton Weng
Ursula Zangrilli
Drs. Chun and Dougherty
• Objective
• History
• Proposal
• Short Term Goals
• Long Term Goals
• Almost Everyone Uses Portable Electronics
• Palm Pilot (200 mW), MP3 Players (110 mW), Laptops (10 W)
• All run out of power in a matter of hours
Objective
• Design a device to generate electrical power from the human body
1) Various devices that convert human mechanical
to electrical energy
2) A circuit to harness this energy
• Use this power to charge the batteries of portable electronics
• Harness enough electrical power to charge a laptop battery
History
Tess Zangrilli
History
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MIT option one:
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Figure 1: Shoe with
Piezoelectric
generators
1-2 mJ / step
History
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MIT option 2
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Figure 2: Shoe with
magnetic generator
.23 Watts
History
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Inventor Ivan Sarich
US Patent #6281594
Transmit power from
foot to waist
Figure 3 – Patent Design
Figure
History
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Seiko Thermic Watch
Seeback Effect
History
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Seiko Kinetic Watches
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Kinetic Energy Storage Unit
 Components
Advantages
 Auto Relay
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History
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1.
2.
Environment
NASA: Micro-wave power receivers
Hitachi Central Research Laboratories:
Convert natural vibrations to electrical energy
History
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UCLA, Heliomite Block Diagram
The Idea
Ross Martin
The Idea
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Shoe based generator
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Incorporates piezoelectric strips
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Parallel and layered design
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Each strip produces 40 volts peak-to-peak per
pulse
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Final output is an AC voltage
The Idea
The Problem: AC waves cannot charge the battery directly
The Idea
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Next step is AC->DC Conversion
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Pass AC wave through transformer rectifier
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Capacitor filter smoothes the wave even
further
The Idea
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Converting the voltage for charging
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Li-Ion batteries operate in specific voltage
range
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Fluctuations or overcharging are not desired
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Same applies for current, though more flexible
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Pulsing of charging can reduce overheating
Shoe Charging Circuit Schematic
The Idea
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Circuit attached to heel/sole
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Phone can be held in standard hip holster
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Wire feeds power to battery being charged
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Standard charging plug for phone
Costs
Tao Nguyen
Factors that affect cost
Type of shoe
 Number of piezoelectric strips utilized
 Number of components used in circuit
 other materials/devices
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Cost Estimates
Piezoelectric strips:$7 per strip
 Circuit components:about $10
 Shoe:$35-60
 Total cost approximately $50-80
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Future Goals
Complete the Circuit
Required Parts
 Calculations
 Size Considerations
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Testing
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Piezoelectrics
Stress
 Heat
 Pressure
 Output
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Comparing with other materials
Complete Cost Analysis
Gain more Accurate Costs
 Compare Prices
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Reports
Keep up with Reports
 Keep Professors up to date
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Have a Circuit built by Summer
Questions?