Mechanical Footsteps Power Generator
Senior Project
By: Faisal Alonazi
Partner: Mohmmed Aljohani
Presentation:
ABOUT
This project was motivated by the need for a device that would generate electricity from human motion, especially footsteps. Electricity is a very important resource in our daily life. There are numerous sources from which generate electrical energy. The major sources of energy include but are not limited to coal, natural gas, petroleum, and nuclear energy. Most of these sources have adverse effects on the environmental inclusion such as air pollution; for example, from coal energy generation plants which then cumulatively leads to effects such as increase in rates of global warming. This project seeks to establish an environmentally friendly way of generating electric power from human motion. Such a system could be highly effective for installation in places that expect frequent mobility of a large population such as in educational institutions like universities and subway station entrances and platforms. The device will generate electrical power as non-conventional method by simply running on the train in the footstep. Non-conventional energy system is very essential currently to our nation. Non-conventional energy using footstep needs no fuel input power to generate the output of the electrical power. This project using simple drive mechanism such as rock and pinion assemble and chain drive mechanism. For this project the conversion of the force energy into electrical energy. The control mechanism carries the rack & pinion, D.C generator, battery and inverter control. Various applications were discussed and further extension. So this project is implemented to all foot step, the power generated is approximately 2.08 volts/step.
ANALYSIS & CONSTRUCTION
Analysis:
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A1: Spring constant calculation: using force of 180 lb and compression distance of 5 inches allows us to determine spring constant.
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A2: The calculation of pinion design.
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A3: The calculation of the maximum stress possible on the pinion.
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A4: finding the power based on the calculation of the torque>
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A5: finding the pinion minimum diameter.
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A6: The calculation of linear velocity of the rack.
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A7: calculation of the gear.
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A8: calculation of the volts generated based on the power applied.
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A9: calculation of the gear ratio.
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A10: calculation of the gear speed.
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A11: calculation of the contact stress of the pinion.
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A12: calculation of the bending of the pinion.
Requirements:
-It must generate 2 Volts for each step.
-The top plate must move down 5 inches and returns to its initial position.
-It must support the weight of 180 pounds
-The device must be less than 20 pounds
Spring Design
spring, shaft, rack, gear
Construction:
The device has a top plate that moves down five inches when applying 180 pounds on it, and it must go back to its initial place when removing the force. In order for this process to happen, two springs were added to the design. The springs must be placed under the top plate and must hold its position. To keep the springs in place, two holes were drilled on the top plate and two holes on the supporters. The design was edited to have two springs placed in the shafts, and the shaft must be screwed on the top plate and go through the holes on the supporters. That will help keeping the springs in its place and improve the outcome of the device.
TESTING & RESULTS
Testing:
The purpose of the device is to generate electricity from human motion. Therefore, the device will be tested on carrying a maximum load of 180 pounds. The process of testing the device is to have a person weight as the source of load by stepping on the top plate. Electricity generated will be measured using voltmeter. The device will also be tested for some safety factors, such as electricity insulation to make sure there is no electricity leak that could cause electric shock. The device must be safe for human use. Therefor, the device must maintain balance. Moreover, the performance of each part of the device will be tested separately.
Results:
1. The device generates approximately 2 volts for each step.
2. The top plate moves down 5 inches and returns to its initial position.
3. The device supports a weight of 176 pounds.
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BUDGET & SCHEDULE
Schedule:
The estimated time for manufacturing parts was slightly less than the actual time needed to make the parts due to several reasons. For the welding parts, the right process for welding was not indicated in the drawing. The welding must hold the right plate perpendicular to the supporting plate, that was indicated in the drawing, but the method for welding a part on specific angle was not known. The problem was indicated few minutes before working on the part. Due to the unexpected issue, the process was put in hold until the research is completed. A few solutions were found online for the same problem. The method was determined best for the project is to weld two pieces of angle iron and make the angle between them 90 degrees and use clamps to hold the parts on the angle iron. After setting it up that way the process was resumed, and the welding was completed as planned.
Budget:
The budget for this project was estimated to be $135. The percentage used from the budget is %146.15. The budget was calculated to cover all raw materials, and all the parts that need to be ordered online. However, A few aspects were not considered when calculating the budget, such as tax and delivery charge.
