Presentation on a concept of "energy harvesting through footsteps" made as part of a project on alternate energy at Noorul Islam University

1. Energy Harvesting Through Footsteps
Project Guide: Prof.T.Judson Durai Team Members:Saran S.D, Sankar R.S, Sharon.M,Sherin Johnson
Department of Mechanical Engineering
Noorul Islam University
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2. Energy Harvesting Through Footsteps
“A rack and pinion based device to
convert the footsteps of the user into useful energy”
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3. Project Objectives
 To form an effective energy harvesting concept
 To form a practically applicable system to demonstrate the energy harvesting
concept
 To design and fabricate the system
 To test the system under various models
 To find applications for the system
 To explore further scope
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4. The Need
Fast depleting natural resources
 Coal is projected to enter production decline by 2030
 Over dependence on coal based and other
conventional methods for power generation
 87.55% of India’s power production is based on non-renewable
resources
 60% of India’s total power production is coal based
Lack of adequate power supply
 Despite being the third largest power producing nation,300
million Indians lack access to electricity 4

5. Energy Harvesting
 The process by which energy is derived from external sources, captured, and
stored.
 The input is not deliberately created for the purpose of power generation.
 Taps energy that otherwise would’ve gone wasted.
 Usually produces low outputs, suitable for small applications
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6. Energy Harvesting Through Footsteps-Working Principle
• Faraday’s Law: “As long as there is a change in magnetic flux linked
with the coil, an EMF is induced”
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7. Components
 Spring based suspensor
 Rack and Pinion
 DC Generator (Magnet & Coil)
 Rechargeable Battery
 Inverter
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8. Basic Design
 Step mounted on spring based suspensor.
 Suspensor connected to vertical rack.
 Rack connected to pinion ,whose axis is connected to a generator.
 Generator is linked to a rechargeable battery.
 Battery is connected to a inverter.
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9. 9

10. Working
 User walks through the step.
 Footstep activates the rack and pinion .
 Generator connected to the axis of the pinion is activated.
 An EMF is generated according to Faraday’s law.
 Electric power generated is stored in the rechargeable battery.
 Inverter module gives AC output .
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11. Footsteps
Rack & Pinion
Magnet &
Coil
Rechargeable
Battery
Inverter
Block Diagram
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12. Selection of Components
 Rack and Pinion
 Rack and Pinion made of plastic
 Rack has a length of 13 CM and has 65 teeth
 Pinion has a diameter of 1.7 CM and has 15 teeth
 Rack and Pinion sourced from a DVD drive
 Selection helped save cost and weight
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13. Rack
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14. Pinion
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15. Selection of Components
 Suspensor
 Spring based suspensor
 Two springs of 5 CM length, 50 turns are used
 Springs attached to the plate containing the rack and a plate below the
rack.
 Connections made using copper harness
 Generator
 A simple generator of 12 V output is attached to pinion.
 Output of the generator given to rechargeable batteries
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16. Suspensor
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17. Generator
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18. Rechargeable Battery
 Two lead acid batteries of dimensions 9.2x9.7x6.7 CM used.
 Each battery having output 6V-3.5A, combined output of 12V-3.5A .
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19. Inverter
 Inverter used has two transistors
 Pulse Width Modulation Generator coordinates input to transistor
 Transistor supplies input to coils
 Coils convert DC from battery to AC
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20. Design
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21. Design Requirements
 System must demonstrate power harvesting
 System should withstand weight
 System must be portable
 System must have real time indication of power harvesting
 System should demonstrate practical applications
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22. Steps in Designing
 Design of support base
 Design of Footstep
 Design of Supports
 Design of demonstration circuit
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23. Design of Support Base
 Support Base designed to hold the weight of the setup, and add stability.
 Flat surface with two protruding ends to act as stand
 Dimension of 45.1x30x3.2 CM
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24. Design of Footstep
 Footstep designed to be retractable
 One side of the footstep is fixed, other end being loose
 Dimension of 18x5 CM
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25. Design of Supports
 Supports are designed in the shape of U
 Two supports will be used to hold the steps
 Dimensions 34.5x2 CM
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26. Design of Demonstration Circuit
 Designed to show the practical application of the system
 Consists of generator, inverter and a household lamp
 Circuit is triggered using a key
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27. Fabrication
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28. Steps in Fabrication
 Fabrication of support base
 Fabrication of footsteps
 Fabrication of supports
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29. Fabrication of support base
 Support base was fabricated out of wood
 Wood was sawed off, and polished
 Stands were nailed into the wood
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30. Fabrication of Footsteps
 Footsteps are fabricated using sheet metal
 Sheet metal is cut and bend into the shape of steps
 This sheet metal was screwed into metal supports
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31. Fabrication of Supports
 Supports are made from cast iron
 Cast iron was cut using hack saw and later welded together
 The cast iron was bend to form curves
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32. Final Model
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33. Testing
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34. Objective of Testing
 To assess the performance of the system based on the response.
 Test Models Used:
 Testing with different weights
 Testing with different rate of weight application
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35. Testing with Different Weights
 To assess the performance of the system under different weights
 Weights of 1 Kg ,5 Kg and 10 Kg were used
 In all cases, consistent output of 12 V was obtained
Sl
No
Input Weight (in KG) Output (in Volt)
1. 1 12
2. 5 12
3. 10 12
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36. Testing with Different Rates of Weights
 Intended to test the performance under different rates of weight
 Tests were carried out at the rates 1, 5 and 10 steps per minute
 In all cases, an output of 12 V was obtained
Sl No Rate of Footsteps (No.of times per minute) Output (In Volt)
1. 1 12
2. 5 12
3. 10 12
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37. Observation
 Consistent output is obtained under application of different weights and
different rates
 The model can be employed at used under varying load conditions and at
varying rates of load.
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38. Applications
 Energy Generating Staircase
 Self Illuminating Pathways
 Burglar Alarms
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39. Energy Generating Staircase
 Multiple energy harvesting systems can be applied in staircases to obtain a
greater amount of energy
 Can be used in shopping malls, railway stations etc
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40. Self-Illuminating Pathways
 Pathways that light up when user steps on it
 Suitable for application in homes
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41. Burglar Alarms
 System can be hidden under carpets next to windows, doors etc
 Burglar alarms can be connected to the system, which will be triggered upon
unauthorized entry
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42. Scope of The Project
 Fabrication of more rigid system
 Fabrication of supports with lighter and stronger materials
 Multiple systems can be installed under staircases to harvest more power
 Real time testing can be carried out instead of using weights
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43. Conclusion
 The rack and pinion based power harvesting system is found to be effective
 The system is cost effective and light in weight
 The system has a variety of applications
 The system harvest enough power for practical applications, without
significant input
 The system has large future scope
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44. Thank You
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