At the moment cord free .. er .. mice .. need to have batteries plugged into them, or after a while need to be plodded up onto a cradle to get some power into them.

I want a cordless mouse I can just leave on the pad - and it always has power. Oh and it has to be optical not roller-ball.

My idea? The mouse-mat has a lead coming out of it that goes to the power supply. The mouse has a positive and negative connector underneath it (flat). The mouse mat itself has thin metallic stripes running through the surface of it, which are positive and negative in turn. As you move the mouse around, it will be spending at least 50% of it's time finding it's connectors connected to the right combination of + and -, and therefore it can get power into a small internal battery (that is only there for those times when the mouse is not touching the right connectors).

OK 50 % of the time the mouse will not be getting any power and the connectors arn't touching the strips of metal, or they are touching the wrong connectors, but this shouldn't be a problem cos of the small internal battery.

No cradle. No replacing of the battery.

Of course you won't get electricuted from your mouse mat just like you don't get electricuted from the mobile phone charger as you touch the metal bit!

ADDITIONAL IDEA I got close to but gave up on ..

I was going to do this same idea but with the mouse being charged through kinetic energy generated by the thing being used (a bit like kinetic wrist watches), but couldn't think of anything that would stop the mouse slowely running out of power if not used for a long time - as it keeps having to shine a light to keep checking if the user has suddenly come back to his PC. (I certainly don't want an on/off switch).
-- britboy, Nov 16 2004

Wacom http://www.wacom.com/index2.cfm
Tablets, pens and Mice - Baked [zen_tom, Nov 16 2004]

Arnold Fixed My Inductive Charger http://www.afrotech...ldpad/arnoldpad.htm
A homemade inductive charger. [Freefall, Nov 16 2004]

Power Spots http://www.halfbake.../idea/Power_20Spots
Less Ahnold-infused discussion of the above, by [rmutt]. See links--two companies are baking this. [krelnik, Nov 16 2004]

A4Tech NB-30 BatteryFREE http://www.hardcore...ws/review-249-1.htm
Wireless mouse that uses an inductive pad powered by a USB cable. [krelnik, Nov 29 2004]

An inductive charger would be a better option. It requires no metal to metal contact. I've got a shaver that uses this. Uses electromagnetism to send power through insulators. I'll link to some info if you want.
-- swamilad, Nov 16 2004


I'm visualizing a "bumper cars"/"dodgem cars" setup with the mouse in a cage. Electrodes on the bottom of the mouse, and a pole with an electrode connecting to the top of cage. That would need to make lots of big sparks for the proper effect.
-- half, Nov 16 2004


Seriously you guys, Wacom have been making these for at least 5 years - I had one a while back, and though I preferred the pen, the mouse worked really well too. I'm not sure how they actually work, but imagine it's something along the lines you describe.
-- zen_tom, Nov 16 2004


One interesting thing about the Wacom mice is that they can function as either absolute or relative coordinates devices (as can the pens) which make them very useful for digitizing, or tracing, line art and CAD stuff.
-- bristolz, Nov 16 2004


Why not just embed the optical part of the mouse into the mouse pad? The mouse then just becomes the tracked surface and would be wireless.
-- Worldgineer, Nov 16 2004


I like the kinetic idea better.

You're biggest problem with it isn't really a problem. Just have the mouse turn itself off after some amount of time. How does it wake up? Simple: when you move the mouse, the swinging weight used to generate the electricity will give a pulse or energy. Use that to turn the mouse on. Of course it will probably loose a bit of movement while it's turning on, but after being idle for a while, the user probably has to wiggle the mouse a bit to find it anyway. And in cases where the mouse has drained all its power, the user may need to shake it back and forth for a few seconds to charge it up.

My biggest worry is that you couldn't generate enough energy from normal use. Mice are pretty low power, but watches are even lower power.
-- scad mientist, Nov 16 2004


The thin strips of metal could become corroded, shorted out by spilled drinks, and so on. I think [Freefall] has the right idea by suggesting inductive charging. See the halfbakery idea "Power Spots" (and the links within) for details.
-- krelnik, Nov 16 2004


Thanks guys appreciate the comments will certainly review the links ...

cheers ..
-- britboy, Nov 16 2004


The inductive version of this is actually baked! See my latest link.
-- krelnik, Nov 29 2004



random, halfbakery