Arduino powered rc car

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1

I've gotten myself a rc car with the thought of ripping out the default receiver and replacing it with an arduino mega board.

Since I realized this has a high potential of frying my board if I mess up I've come seeking help and advice.

The receiver is a RX-2B (datasheet)

And these would be pictures of the actual receiver circuit.

The drive and steering are controlled by 2 DC motors (though I'll replace the steering one with a servo sometime soon to get smooth steering). I'm not sure what type they are but I've checked the voltage on them and it's around 4.8. This seems fairly accurate since the whole car runs on 4.8V

Since I know a DC motor shield exists for arduino boards, and probably for a good reason, my question is: can I safely hook up the 2 motors directly to the arduino board(considering the voltages are under 5V) ?

Or, I could remove the receiver from the circuit and just connect some digital out pins to where the original the forward, back left and right pins were.

Any ideas suggestions or explanations of why I'm wrong are all equally appreciated.

Thank you for your time

2

You won't be able to directly connect your dc motors to the digital pins on the arduino because the pins can only source 40mA and your motors probably draw more current than that. A common way to power motors is to use an H-Bridge, which will allow you to control the direction and speed of the motors using the digital pins on the arduino. Here is an example http://itp.nyu.edu/physcomp/Labs/DCMotorControl

3

isnt that an hbridge on the board already? I can't tell cause of the glare but the pinout seems correct... if it is, you can save yourself the 7 bucks and scavenge it off the board.

4

Thank you for the replies.

Yes there are 2 hbridges built with transistors. I doubt that will fix the low current issue.

The motors seem to be the type used in servos, but again I'm not sure. I'd just hook them up to test, but If I try running them right off the board, will they not run, or would the board fry?

An indication of what can go wrong (and why) would be extremely appreciated.