TechTheDay

This post is inspired by some recent article about the electricity-generating smart shoes developed by a 15-year-old student. For many who are fond of reading tech articles, such a concept is no longer novel. It has been reported in various tech sites before. There have been many “smart shoes” developed by people from different parts of the world.

However, it is worth giving a second look at the news about the teenage boy who has thought of something useful and somewhat advanced for his age. It is also worth looking back at the different electricity-generating shoes created over the past few years.

The Teenage-Built “Smart Shoes”

Angelo Casimiro, a 15-year-old Filipino student, created a project he called “Electricity-Generating Footwear” as his entry for the 2014 Google Science Fair. Interestingly, Casimiro says that he only spent P304.00 (around $7) to complete his project, mostly due to the use of recycled materials. He adds that he had been working on this project for around five years, starting with a design that involved a T0-3 plastic spacer enveloped by two piezo discs, capable of charging the battery of a Nokia 3310.

Casimiro’s invention is an insole generator positioned inside a pair of old sneakers and connected to a portable power bank. The portable power bank can be used to charge mobile devices and other devices that can use battery juice from a 5 volt power source. The primary technology being employed is piezoelectricity, a rather old technology that can be created using outdated earphones produced from the 90’s.

The whole setup is shared on Instructables.com so those who want to try reproducing this cheap but useful invention can proceed to doing it.

Here’s a summary:

    Materials and Parts Needed

• 2 USB power banks
• 4 1N4007 rectifier diodes
• 6 piezoelectric transducers or a pair of old earphones
• Wire (12” minimum)
• Adhesive
• PVC for the insoles
• Pieces of foam
• Pair of Shoes

    Tools and Equipment Needed

• Multitool or Pliers
• Multimeter
• Rotary Tool or a Hot Nail (or a similarly sized metal that can be heated to melt plastic)

Basically, what needs to be done is to create insoles by cutting PVC into a suitable shape and size. Next, holes are created on the PVC insoles in which the piezo discs are attached. Three piezo discs will be attached to each insole. After the discs are attached, they will be connected with wires. Of course, the wires have to be soldered on the piezo discs to ensure proper conduction. Small pieces of foam will then be added on top of the piezo discs to act as “pushers.” Force will be exerted through them to induce mechanical stress that enables the generation of electricity. All the details and schematics to create a functional setup are presented on the Instructables page indicated above. You can also view this instructional video on YouTube if you prefer a video guide.

Once the setup is done, a multimeter is then used to test if power is indeed generated. Casimiro’s test showed that pressing the insole by hand generates 15.03 voltes at 2mA. Walking with the insoles installed creates 18.53 volts at 5mA. Running, on the other hand, produces 27.89 volts at 11mA.

About the battery—what Casimiro did was to attach the batteries to the sides of the shoes. Obviously, it will be more convenient to gather the small amounts of electricity produced in little power banks first instead of directly connecting chargers to the insoles to charge devices while walking or running.

Other Power-Generating Shoes

As mentioned earlier, electricity-producing shoes are not new. There have been a few of them reported in the past. In mid-2013, a group of mechanical engineering students at Rice University developed shoes they called PediPower to convert motions into electricity. Even earlier, in August 2011, “nanopower” shoes capable of generating 20W of power while walking, were already invented. They were created by researchers from the University of Wisconsin Madison. The technology was given the name Instep Nanopower.

What makes the teenager-developed “smart shoes” worth writing about, though, is the low cost and ease of construction. It may not be a new idea but it’s something a young student was able to achieve by doing his own conceptualizations and tests. His work may need some more fine tuning but it’s always great to know that younger people are getting interested with science and technology, and are not only concerned about the latest gadgets or retail tech products.