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1. _______________________________________________ • The motivation for the project is to prove that a useable amount of energy can be captured from everyday motion • The objective is to build a device that captures energy which is otherwise wasted • Project focuses on converting human mechanical energy to and storing as electrical energy in a turnstile • Turnstile design 1.0 consists of a crank attached to a system of gears which spin a generator at high speed to produce electrical energy • Large scale turnstile potential • 20 turnstiles in continuous use could yield 16K full turns per hour • 350 est. pedestrians charges a 2.7V 100F supercap to 80% of full charge (230J) • With average efficiency taken from 0-90% charge of cap voltage range, the arrangement would capture 35KJ/hr • Proof of Concept: a hand crank turning a 10:1 belt driven wheel attached directly to the generator and then to a bank of LEDs • Proved that cranking would charge supercapacitor and illuminate LEDs in a reasonable amount of time • Volts/RPM measured using an optical tachometer to find appropriate gear ratio • Target Project Specifications ✓< 20lbf to rotate crank ✓Generator output > 3V at peak from 1/3 of a crank rotation in 1.5 seconds ✓< 3 sets of meshing gears ✓Standard size turnstile frame must enclose gears and all crush points ✓Multicolor LED display to sequentially illuminate as capacitor charges ✗ Energy conversion efficiency > 40% Actual average efficiency = 10.2% measured between 0-90% of full cap voltage ✗ Dual voltage output boost power supply active when cap voltage exceeds 1V (heat failure) ☐ Ratcheting arm mechanism with flywheel • Supporting Engineering Analysis • Permanent magnet DC generator must spin at a minimum of 800 RPM at peak for the supercap to charge effectively • Gear ratio must be 60:1 assuming 13.3 rotations a minute (40 people passing through per minute) • LEDs become active at certain intervals as the supercap is charged using variations in diode forward voltage drop characteristics • Project status • 2.0 model will address unresolved issues • Supply redesign necessary due to heat concerns • On track for project completion in May 2014 • Second semester recommendations • Design a ratcheting turnstile arm to replace crank • Design a flywheel to boost efficiency to 20% • Find power ICs in manageable package sizes and incorporate a SMD adapter • Debug in time to get a reliable PCB manufactured SPICE Boost Power Supply Schematic Department of Mechanical & Industrial Engineering