Subdermal Induction Microgenerators?
As this is my first post, I'll begin with a short introduction. I learned about the grinder movement purely as a result of chance and curiousity (thanks @Lucas_Dimoveo for that well-placed post on the MO forums!). I have very little technical knowledge (currently rectifying this) and no implants, but already I unintentionally think of myself as a grinder. When I told my neighbour about @DirectorX 's audio implant, I couldn't understand why she was so aghast at the idea! Like so many others, in a matter of days this movement has captured me and made me its own.
Now, on to my idea. Let me begin by stating (again) that I have very little technical knowledge of the subject I am speaking to; I hope only to offer some inspiration to those with more knowledge than I.
Reading these forums, it became readily apparent to me that the primary issue slowing most grinders is that of power sourcing. While reading thread after thread of great ideas for modules that get shot down due to the inconvenience or downright impossibility of keeping them charged, one thing kept surfacing in my mind: the batteryless flashlight.
I'm sure you're all aware of how a batteryless flashlight functions, and have probably already looked into this idea for the same reasons I have. It seems almost perfect; the body is in constant motion, and motion is all that is needed to generate power with the simple induction coil-and-magnet I'm thinking of. I began researching other uses found for this generation technique, and found this:
Followed by this:
TL;DR Back in 2007, the US DoD put out a venture capital 'prize' for the company that could come up with a viable, miniaturized method for keeping individual soldiers' increasingly technical equipment charged. M2E Power came up with a solution in the form of a battery-sized (I know, very vague) induction microgenerator similar in many ways to that used in a flashlight. It was swiftly snatched up by Motionetics Inc., about whom I have been unable to find much information of use.
So, to those of you with more technical know-how than I: is this a viable power source for us? I picture it highly miniaturized and placed subdermally near high-impact joints to provide the most vibration for induction; perhaps even a network wired together with a common energy storage module. Some immediate cons I came up with were the possibility of tissue trauma, as there would be near-constant motion in this module; and I would think a heavy energy decay rate without a storage device (I'm thinking again of the flashlight which had to be shaken every hour or so).
Edit: My apologies, I just noticed that @ThomasEgi previously started a discussion along a similar vein :\ Perhaps I've unintentionally mentioned something new that will spark productive discussion....
the main problem is that there is a lack of available devices to experiment with. so we lack actual numbers for power output based on the implant location, the size of such devices, the lifetime aswell as any other potential drawbacks such as mechanical noise (since they have moving parts).
especially lifetime of such a device would be interesting. as consumer products are engineered to break just after the warranty ends.
@rezin. well in theory it could work if you use one magnet and a coil (instead of 2 magnets). but in practice the magnetic field change you cause in the coil is rather small (as there is a big air-gap between your legs), and it hapens pretty slowly,too (so the induced voltage is very small). i'd say, based on my physical "feeling" that coil and magnet would have to be pretty big to produce a useful ammount of power.
my best guess on harvesting mechanical energy would be either based on masses bending small piezo elements. or the traditional magnet-in-a-tube.