Which servo controller for use with cell phone?

Support Servo controllers and servos
1

Hello,

I’m a beginner with this, so bear with me :slight_smile:

Which servo controller would be a good choice, if it was supposed to be commanded by a cell phone?

I initially though of usb-cable connection, but I was advised that this would not work as the cell phone would have to be the slave part when using usb. So what would work?

I think Bluetooth communication might work, but BT-to-serial adapters are really expensive (around $150) and it feels like making it unnecessarily complicated, any better ideas?

Thanks!

2

Hello,

This is going to depend which model of phone you have. For example, serial over Bluetooth would be a nice way to go, but many phones have Bluetooth restricted to only work with headsets. Also, do you already know how to write programs for your phone?

-Paul

3

Hi Paul and thanks for the quick reply!

I was planning to try Nokia’s 5800. I’m not very experienced with Bluetooth at all, but this is what the device specs say:

  • Bluetooth 2.0 +EDR
  • Profiles: A2DP, AVRCP, BIP, DUN, FTP, GAP, GOEP, HFP, HID, HSP, OPP, PBAP, SAP, SDP, SPP

I got to confess, at present I have no idea if that restricted or not, but I don’t think it’s just for headsets.

I do have some experience with S60 phones and the Symbian environment, but I was planning to use J2ME as Java is my main language. I am a programmer, but I have not written this sort of (robotics) code before :slight_smile:

4

So anyone got ideas for this :slight_smile:

The idea is that the controller and the phone sending the commands are really close together anyways, so it really could be using a cable connection - what ever type of connection works.
Like said, USB was my initial plan, but then I learned about the master-slave relation with USB connections, so I guess that wont work.

But is Bluetooth the only option here or am I overlooking some other possibility?

Here’s a link to the specs of the phone I’m planning to use:

forum.nokia.com/devices/5800_XpressMusic

I’m planning to use J2ME for the programming, but I’ll go for Symbian if necessary.

5

Well, the phone claims to support SPP (bluetooth over serial), so you can probably get that to work. I really know nothing about programming mobile phones, but I think you are right about USB not being possible on this model. Some phones, I believe do have the ability to act as both USB hosts or devices, but this doesn’t look like one of them.

Bluetooth also has the advantage that you won’t have any direct electrical connection to your phone, so there is little chance that motor voltages could damage it. Good luck!

-Paul

6

I have no experience with development on a cell phone, but it seems like the main issue will be getting control of some wired signals that go outside of the phone (and I don’t know if there are any besides USB), so I would look for some documentation or sample projects that describe this sort of external control.

- Jan

7

Thanks guys!

Well, it seems I better check out what other phones are available also, before I start implementing this. (I haven’t bought the phone yet, I just like the 5800 for other features like gps and wi-fi and I used that phone before at work).

Thanks for pointing that out, if it turns out that Bluetooth is the way to go, then what would be a good choice for the controller?

I’ve been looking at the Pololu Serial 8-Servo Controller (assembled) for example, but then I would need a Bluetooth-to-serial adapter as well, right? I mean there doesn’t seem to be ready-made bluetooth servo controller? Any options for this?