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: MIT option one: Figure 1: Shoe with Piezoelectric generators Figure 1: Shoe with Piezoelectric generators 1-2 mJ / step 1-2 mJ / step

History MIT option 2 MIT option 2 Figure 2: Shoe with magnetic generator Figure 2: Shoe with magnetic generator.23 Watts.23 Watts

History Inventor Ivan Sarich Inventor Ivan Sarich US Patent # US Patent # Transmit power from foot to waist Transmit power from foot to waist Figure 3 – Patent Design Figure Figure 3 – Patent Design Figure

History Seiko Thermic Watch Seiko Thermic Watch Seeback Effect Seeback Effect

History Seiko Kinetic Watches Seiko Kinetic Watches Kinetic Energy Storage Unit Kinetic Energy Storage Unit Components Components Advantages Advantages Auto Relay Auto Relay

History Environment Environment 1. NASA: Micro-wave power receivers 2. Hitachi Central Research Laboratories: Convert natural vibrations to electrical energy Convert natural vibrations to electrical energy

History UCLA, Heliomite Block Diagram UCLA, Heliomite Block Diagram

The Idea Ross Martin

The Idea Shoe based generator Shoe based generator Incorporates piezoelectric strips Incorporates piezoelectric strips Parallel and layered design Parallel and layered design Each strip produces 40 volts peak-to-peak per pulse Each strip produces 40 volts peak-to-peak per pulse Final output is an AC voltage 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 Next step is AC->DC Conversion Pass AC wave through transformer rectifier Pass AC wave through transformer rectifier Capacitor filter smoothes the wave even further Capacitor filter smoothes the wave even further

The Idea Converting the voltage for charging Converting the voltage for charging Li-Ion batteries operate in specific voltage range Li-Ion batteries operate in specific voltage range Fluctuations or overcharging are not desired Fluctuations or overcharging are not desired Same applies for current, though more flexible Same applies for current, though more flexible Pulsing of charging can reduce overheating Pulsing of charging can reduce overheating

Shoe Charging Circuit Schematic

The Idea Circuit attached to heel/sole Circuit attached to heel/sole Phone can be held in standard hip holster Phone can be held in standard hip holster Wire feeds power to battery being charged Wire feeds power to battery being charged Standard charging plug for phone Standard charging plug for phone

Costs Tao Nguyen

Factors that affect cost Type of shoe Type of shoe Number of piezoelectric strips utilized Number of piezoelectric strips utilized Number of components used in circuit Number of components used in circuit other materials/devices other materials/devices

Cost Estimates Piezoelectric strips:$7 per strip Piezoelectric strips:$7 per strip Circuit components:about $10 Circuit components:about $10 Shoe:$35-60 Shoe:$35-60 Total cost approximately $50-80 Total cost approximately $50-80

Future Goals

Complete the Circuit Required Parts Required Parts Calculations Calculations Size Considerations Size Considerations

Testing Piezoelectrics Piezoelectrics Stress Stress Heat Heat Pressure Pressure Output Output Comparing with other materials Comparing with other materials

Complete Cost Analysis Gain more Accurate Costs Gain more Accurate Costs Compare Prices Compare Prices Keep up with Reports Keep up with Reports Keep Professors up to date Keep Professors up to date Reports

Have a Circuit built by Summer

Questions?