Step 3: Prepare the Battery

There are 2 sets of 4 batteries in the stock R2, 4 x AA for running the controllers and 4 x D for driving the motors.  The IOIO takes 5-15V and 4 rechargeable D cells would give me 4.8V, and I wanted to make sure that the voltage will be able to power an Android phone off of the IOIO USB port eventually, so I opted for an 8 x AA battery holder, for 9.6V that fits perfectly into the compartment.

I drilled a 3/8" hole through to the back of the compartment and threaded the female barrel connector through. 

With 5V-15V in through the JST connector, the IOIO delivers either 5V or 3.3V out through the pins and 5V out through USB to power a smartphone device. Although the IOIO can theoretically supply 1.5A at 5V, my brother-in-law fried an IOIO running fairly small motors directly off an IOIO, so I decided to splice into my battery output and run a direct 9.2V wire to the Motor Driver.

Note:  The increased voltage overdrives R2's motors a bit, so he's faster, but it could eventually burn them out - more testing required.

This is awesome. I've had my R2 for years now too and I've just been too lazy to try and get him more up to speed with technology. I'm looking forward to seeing more of this! <br> <br>Thanks!
It took me a while to get to this point as well, but within the next few weeks I'll hopefully have a remote program that will allow you to have a full-on remote telepresence R2 Unit! <br> <br>Thanks!
I rewired into a more simple configuration to deliver 5V power to the motors directly from the IOIO and it seems to be working well, without the board heating up much after a few minutes of wandering around.

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Bio: I am an ER doc in central California that enjoys the outdoors, has a small gadget problem and has a huge interest in sustainability and ... More »
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