I am building a large robot. I am trying to make a mat like device that the robot can drive over and get some electricity. I am not trying to charge it although suggestions for charging 12 volt lead acid batteries would be great. I am trying to give it enough power to run just 1 Arduino Duilminove and one of those 38Khz IR remote control receivers. so that would be something like >5 volts at 60 mA? how would I go about doing this? Does any business sell inductive power transfer devices for hobbyists? All help is appreciated
This sounds like the sort of thing that is used to charge electric toothbrushes, although they typically use concentric coils for maximum transfer - I think they still don't transfer much current. I suppose if you could get produce a field of magnets with adjacent magnets having opposite polarity and with each magnet alternating, you'd get a continually changing field which would induce a current into any coil in the area. No idea how effective it would be, but I wonder what that would do to the electrics and electronics of the Arduino itself?
Hi,
inductive power transfer might be pretty awesome, but it's less suitable (strong inteferences) and maybe too expensive for your project.
I would attach two large pads on the bottom of the robot and let the robot drive over a mat with "brushes", which touch the pads and charges the robot.
my robot project is not going to be cheap, I would love some more information about inductive charging (my robots base is 2 feet by 3 feet)
I would also liek some more information on the brush method.
Hi,
about the brush method:
Do you know Carrera cars?
They are powered by the tracks they are driving on.
The cars got metal brushes underneath to make the contact to the metal-lanes on the tracks.
Brushes on the cars:
http://img3.imageshack.us/img3/6623/1313943691242.jpg
Metal-Lanes on the Tracks:
I've seen this done using a pattern of positive and negative pads on one side, with a set of small brushes on the other, each designed so that they can't touch more than one pad and positioned so that the brushes will make contact with multiple pads. Pass the input from each brush into a rectifier, and you have a DC connection that will make itself as long as the two sides are more or less touching.
I think putting this on the floor might not be very safe, because anything conductive touching multiple pads while they were live would cause a short circuit. But it would be possible, if you really wanted to avoid having any on-board power source or storage.
The original idea sounds like a non-starter. The motor batteries for the robot are gonna
be discharging much quicker than the battery powering the Arduino - assuming spearate
batteries. Inductive charging will take forever, either way.
Many robots have been designed that plug into AC mains for charging, and also that
connect to +/- contacts inside a hutch, including some of the first robots ever built.
http://www.ias.uwe.ac.uk/Robots/gwonline/gwarkive.html
This sounds more practical. Any contacts on the floor and unprotected will likely be a
shorting-hazard.
how good would this work?
http://www.robotshop.com/seeedstudio-300-ma-wireless-charger-2.html
You can do it through induction. Same principle makes induction motors and car alternators able to convert power <==> motion. You have a vacuum cleaner? Chances are is uses an induction motor.
Changing field moves electrons in conductors, yeah you can transfer power. That said, you want your electromagnets and coils to be as close as possible and no, you won't get the efficiency of direct contact, be lucky to get 70%.