Control robot with Android phone

Question

Basically we're building a simple setup with an Arduino board and some motors. The Arduino with motor shield will control several servo motors and DC motors, and possibly talk to a few sensors. This seems to work.

But rather than hook up an XBee, or wifi or something complicated, we'd like to just throw a moto droid into the payload. This would give us A) long range communication through the internet B) a camera we could control via the internet C) realtime video from the droid's camera.

So our question is: the droid has a micro USB port on the side. What's the easiest way to plug that into an arduino (or go-between) and read/write data? I've seen a page where a guy used bluetooth, but I was hoping for a wired connection.

Answer 1

The neatest way I've seen is to drive continuous rotation servos by generating PWM signals as sound from the handset.

There are lots of open source examples of cellphone bots at: http://www.cellbots.com/

http://code.google.com/p/cellbots/

• LoveMeSomeCode: Interesting idea, but is that a wired solution? Are we talking about cutting into the droid's speaker wires? Or just emitting the sound and using the wave shield on the arduino?
• Toby Jaffey: Plug a headphone jack into the Droid and wire the audio outputs to servos (possibly via an amp)
• LoveMeSomeCode: That, my friend, is genius. If only there were a +5 button on here. I'm only irritated I didn't think of it first.

Answer 2

Joby's method is probably the cleanest wired method at the moment. Android is moving toward having USB ports that are called USB On-the-go (OTG) which allows the phone to be a host or a slave. Here is a forum about it.

If you are wanting to be a bit more adventurous with bluetooth you should check out the Amarino.

Answer 3

You probably need USB host mode to interface the phone, the Arduino isn't suitable for that. A controller with USB OTG, such as a suitable ARM device, might work.

• endolith: You mean "the Android isn't suitable for that"?
• Leon Heller: No. The Arduino won't be suitable as it doesn't have host mode and won't be able to communicate with the phone.
• Matthias: @LeonHeller This host shield would solve the problem, wouldn't it?