There is energy everywhere around us and in many different forms. Many devices have been developed to harvest light, wind, waves, and more. One unusual place of energy harvesting is from passing cars. As cars pass by some of their energy is released in form of sound. Even though the overall energy maybe small it can be harvested. In this Instructable I will show how to apply the solution of Euler–Bernoulli beam theory to design a cantilever beam to oscillate at such a frequency to adsorb sound waves as well as converting its mechanical motion into electricity.
Step 1: Materials and Prices
The materials to make one or a similar device can vary based on what someone wants. The most important part is that the oscillator (described in next step) is cut to proper dimensions and firmly clamped to an object so that its vibrations will have little dampening (Less dampening = more power). A few of my components were salvaged from used metal plates and old circuit boards. I encourage testing out your own designs with varying parts. Anyway, this is what I used totaling $39.37:
- 20 pcs piezoelectric wafers…………………………7.07 (need for number of oscillators made)
- 20 pcs MB6S full wave rectifiers………………….6.43
- 10 pcs Printed circuit board (PCB)……………….5.99
- Tripod……………………………………………………….Already owned (suggested but not needed)
- 4 pcs 1/4 x 2 inch bolt…………………………………4 x 0.25 (estimated)
- 4 pcs 1/4 inch washer…………………………………4 x 0.10 (estimated)
- 3 x 0.75 x 0.75 inch square rod…………………..Already owned (Not needed)
- 2 pcs 3 x 2 x 0.25 inch plates……………………..Already owned (Not necessarily needed)
- Hookup wires……………………………………………Already owned
- 2 pcs 10K ohm resistors…………………………….Already owned (Could use others)
- 2 pcs 4.7 micro F capacitors………………………Already owned (Could use others)
- 24 x 12 x 0.062 inch Nylon 6/6 sheet……………18.48
- 6061-T6 1mm thick Aluminum sheet…………….Already owned
One will also need a device to cut, drill, solder, glue and more. I suggest one watch/read this and recognize what tools are needed for what project that it may be applied to. For example, changing the 0.25 inch metal plates to 0.5 inch wood could potential work just as fine if metal working tools are not available.
Read more: Harvesting Sound Energy From Passing Cars
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