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
MIT option one:
Figure 1: Shoe with
Piezoelectric
generators
1-2 mJ / step
History
MIT option 2
Figure 2: Shoe with
magnetic generator
.23 Watts
History
Inventor Ivan Sarich
US Patent #6281594
Transmit power from
foot to waist
Figure 3 – Patent Design
Figure
History
Seiko Thermic Watch
Seeback Effect
History
Seiko Kinetic Watches
Kinetic Energy Storage Unit
Components
Advantages
Auto Relay
History
1.
2.
Environment
NASA: Micro-wave power receivers
Hitachi Central Research Laboratories:
Convert natural vibrations to electrical energy
History
UCLA, Heliomite Block Diagram
The Idea
Ross Martin
The Idea
Shoe based generator
Incorporates piezoelectric strips
Parallel and layered design
Each strip produces 40 volts peak-to-peak per
pulse
Final output is an AC voltage
The Idea
The Problem: AC waves cannot charge the battery directly
The Idea
Next step is AC->DC Conversion
Pass AC wave through transformer rectifier
Capacitor filter smoothes the wave even
further
The Idea
Converting the voltage for charging
Li-Ion batteries operate in specific voltage
range
Fluctuations or overcharging are not desired
Same applies for current, though more flexible
Pulsing of charging can reduce overheating
Shoe Charging Circuit Schematic
The Idea
Circuit attached to heel/sole
Phone can be held in standard hip holster
Wire feeds power to battery being charged
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
Cost Estimates
Piezoelectric strips:$7 per strip
Circuit components:about $10
Shoe:$35-60
Total cost approximately $50-80
Future Goals
Complete the Circuit
Required Parts
Calculations
Size Considerations
Testing
Piezoelectrics
Stress
Heat
Pressure
Output
Comparing with other materials
Complete Cost Analysis
Gain more Accurate Costs
Compare Prices
Reports
Keep up with Reports
Keep Professors up to date
Have a Circuit built by Summer
Questions?