Body as battery

Display screens integrated into contact lenses (image above)? Micromechanical medical devices? Pervasive biosensors? A big challenge in the development of wearable and implantable gadgets is how to power them. Years ago, I wrote about efforts to develop a "glucose fuel cell" and other possible technologies to scavenge power from the human body itself. In the new issue of Smithsonian, Michael Belifore looks at the latest developments in that field, much of which is funded by the Defense Advanced Research Projects Agency (DARPA)'s Starved Electronics program. Belifore is the author of The Department of Mad Scientists: How DARPA Is Remaking Our World, from the Internet to Artificial Limbs. From Smithsonian:

Obviously, our bodies generate heat–thermal energy. They also produce vibrations when we move–kinetic energy. Both forms of energy can be converted into electricity. Anantha Chandrakasan, an MIT electrical engineering professor, who is working on the problem with a former student named Yogesh Ramadass, says the challenge is to harvest adequate amounts of power from the body and then efficiently direct it to the device that needs it.

In the case of harnessing vibrations, Chandrakasan and his colleagues use piezoelectric materials, which produce an electric current when subjected to mechanical pressure. For energy scavenging, ordinary vibrations caused by walking or even just nodding your head might stimulate a piezo material to generate electricity, which is then converted into the direct current (DC) used by electronics, stored in solid-state capacitors and discharged when needed. This entire apparatus fits on a chip no larger than a few square millimeters. Small embedded devices could be directly built onto the chip, or the chip could transmit energy wirelessly to nearby devices. The chip could also use thermoelectric materials, which produce an electric current when exposed to two different temperatures–such as body heat and the (usually) cooler air around us.

"Embedded Technologies: Power From the People" (Smithsonian)

The Department of Mad Scientists: How DARPA Is Remaking Our World, from the Internet to Artificial Limbs (Amazon)

• [classic01]

  Contact lenses display? NOW that’s going to be an awesome augmented reality future!

• [Ugly Canuck]

  So one day it’ll be against the law to batter my battery.
  Cool.

• [MatanArie]

  Keanu Reeves: Whoa. Deja vu.

• [Anonymous]

  DARPA: where billions in boondoggles meet Big Brother.

  Cyborg sharks, anyone?
  Gay-rays?
  The office of Total Information Awareness (and it’s subsequent incarnations)?

  Dismantle DARPA.

  • [MatanArie]

    Oh my gosh!
    Gay-ray wielding cyber-sharks!

  • [Brainspore]

    Dismantle DARPA.

    …says the guy on the internet.

    • [Anonymous]

      Nice straw-man. However, I actual am familiar with RAND and ARPA, and the origins of the internet.

      I’m also familiar with the argument that if we continue to fund DARPA, there will be “side benefits”. It’s like the old argument not to cut NASA’s funding because then we would never have invented “temper foam”.

      But to me, it seems obvious that this “trickle down” or “tossing crumbs” method of research is grossly inefficient for producing non-military applications and a huge breeding ground for graft.

      So here are few questions for you:

      We’re both on the internet, but are we using the internet as a military application?

      Is it conceivable to you that the internet could have been developed without the US military?

      Isn’t the question not about supporting tech research, but supporting US military tech research? Do you understand the difference?

      If the US military simply ceased to exist, wouldn’t there still be good reasons to develop, GPS, prostheses, or the internet? Yet wouldn’t we question the necessity of building cyborg sharks, gay-rays, and Big Brother?

      Given that the US constantly engages in wars of aggression, abuses the civil rights of it’s citizens, and already outspends the entire world militarily, why are you so flippant at the thought of throwing less money them?

      • [Brainspore]

        “Straw-man” is now officially the most abused term in the blogosphere.

        • [Felton]

          It’s official? I’ve suspected it for a long time. :-)

        • [Anonymous]

          “Straw-man” is now officially the most abused term in the blogosphere.”

          How does “blog-o-sphere” rate?

• [Boomshadow]

  “Sorry, boss, I can’t come in today. I’m feeling a bit drained.”

• [bja009]

  DARPA: where billions in funding meets bright researchers.

  GPS, anyone?
  Revolutionary prosthetic arms?
  The internet (and its subsequent transformation of the world)?

  Keep funding DARPA.

  • [Anonymous]

    Good point.
    Because the best way to research a prosthetic arm is to do it while also spending millions on an imaginary gay-ray. Produce nothing, and it’s a little too obvious that you are stealing.

    Personally, I think a civilian agency would do a better and more efficient job of developing things like GPS, prosthetics, or the internet; if they were focused solely on technological innovation instead of military application.

    But hey, maybe you’re right, this is the good ol’USA. We can never spend enough on war. So let’s cut a few more social programs and keep the money flowing to the military’s mad scientists. We always need new methods for killing and surveillance.

• [Lageos]

  It would be great to build in some cooling units in the shoes by using piezoelctric crystalls.
  I’m so interrested in the future of clothing in the next centuries. It’s going to be awesome!

• [Swampdog]

  so, um, hypothetically, excess energy generated by, say, overeating, could be harvested to run my laptop? Sign me up!

• [gman]

  Hmmm, piezo-electric generators embedded in the muscles of a severed limb’s stump, plus glucose fuel cell for extra power, plus the “Revolutionary prosthetic arms” mentioned in the comments, equals futuristic cyberpunk-esque cybernetic limbs.

  Where do I sign up?

• [IamInnocent]

  There’s a market for a device that would generate electricity using fat. Integration into a pajama connected to the grid seems appropriate.

• [Anonymous]

  Hah! Sounds like DARPA has a few Torchwood fans working in the lab…

• [Anonymous]

  Interested in the one that force-grows trees, myself. Dubious value? Only in a world with huge desertification problems and the threat of massive social violence based on lack of access to fresh water.

  Oh, wait…

• [Lobster]

  Invent something that turns body fat into electricity and you’ll change the world.

  Lot of people’ll probably end up charred husks with 0% body fat, too.

• [Anonymous]

  A straw man argument is an informal fallacy based on misrepresentation of an opponent’s position. To “attack a straw man” is to create the illusion of having refuted a proposition by substituting a superficially similar yet weaker proposition (the “straw man”), and refuting it, without ever having actually refuted the original position.

  For example:

  Person A: We should stop funding DARPA due to corruption and mismanagement.
  Person B: Then you wish the internet never existed.

  • [Brainspore]

    I know exactly what a straw man argument is. What I made was a counterpoint to your initial post about DARPA’s track record. If anything your mischaracterization of my post is the straw man argument here.

    Person A: DARPA has funded some projects of dubious value and should therefore be dismantled.
    Person B: But DARPA is also responsible for the internet, an extremely valuable tool that we are both using right now.
    Person A: Nice STRAW MAN, accusing me of wishing the internet never existed.

• [Astragali]

  It’s that glucose fuel cell that’s got me simultaneously intrigued and concerned: Imagine dropping dead from over-using your arm-implanted cell-phone, for example…