PhantomX controlled by a Raspberry Pi

[KevinO]

So here is my work in progress of my PhantomX controlled by a Raspberry Pi. It's running a c/c++ port of the Phoenix software developed by Jeroen Janssen, Kurt Eckhardt and Kåre Halvorsen. This version is all floating point and standard math libraries are used. Body FK is still rough and is prone to glitches so more work is needed. But hey, it's progress. Once the body FK is fixed I will post the code if anyone is interested. Though I would suggest waiting and using Kurt's up and comming Raspberry Pi version since mine doesn't have a GP player or single leg control. (something I don't need or use so I depricated it)

Communication to the servos are done with the Robotis USB2Dynamixel and their SDK. I have one of Xevel's USB2AX from Seeed on order and I am planning to switch to that due to its small form factor. Power to the servos is provided by the Robotis smps2dynamixel. Power to the Rpi will be done with a BEC from Castle Creations when I mount all this inside.

Special thanks to Kurt in writing the Xbee code for the Raspberry Pi so I could still control it with the Arbotix Commander.

[KurtEck]

Looking great!

I have also been playing around with the Raspberry Pi and have it working on one of my Lynxmotion Robots (T-Hex). I have been posting some stuff about it up on Lynxmotion (http://www.lynxmotion.net/viewtopic.php?f=25&t=8607) Mine is still running with fixed point math.

Would like to thank Kevin for all of his help on getting me up and running using Linux.

Again great stuff.

Kurt

[hwan we]

move good robot

[KevinO]

So last week I broke down and purchased a MKII Barebones kit (just the plastics). I felt like I wanted to keep my other PhantomX body setup for the Arbotix just in case I wanted to mess with the Arduino sometimes. So this weekend I mounted my smps2dynamixel, raspberry pi, my Castle Creations BEC and two hubs. Here are a couple of shots so you can see how I mounted it.

I'm not mounting the USB2Dynamixel since I have a USB2AX from Xevel on its way.




So the open area where the Arbotix usually sits is where I have access to the Ethernet and USB ports. I made sure all plugs and gpio were accessable with the servos installed.

[hwan we]

you hope robot completed
made robot so cool

[KurtEck]

Hi Kevin,

Looking good.

I did not get as far along this weekend as I wanted. (Had nice weather on Friday and Saturday)

On mine so far I have started to do the preliminary stuff to mount the Pi on my T-Hex. I updated the battery wiring to install one of my Lifepo4 batteries I purchased awhile ago. I wired up the BEC, and connected it up to one of the USB breakouts from Sparkfun, so I can plug it into my pi to power it. Also wired up a plug to power up my USB hub.

Right now I am working on figuring out some form adapter that allows me to mount the pi. Figure I can use one of the two screw holes with a standoff to connect one corner. Trying to figure out a clean way to use a standoff with some link or the like to connect the other screw hole to someplace on the T-Hex.

Today, I am receiving an Edimax wireless adapter, so I should also be able to then talk to the Pi without wires.

Probably be a few more days before I get everything back into one piece.

Kurt

[KevinO]

Let me know how the Edimax goes. Though as you can see I'm short on space as it is. I'm not sure where I'd put a usb hub. What hub are you using if you don't mind me asking?

I just recieved another email my GPIO board shipped so that'll be something new to play with as well.

[KurtEck]

I was using a different hub (one by linksys), but the one I interfaced is one that I purchased years ago from radioshack, which is pretty small. Also this interface mentioned that other required an external hub, but this one is low enough powered that it can plug directly into the Pi... So we shall see...

[jwatte]

The Pi has real power supply problems. It needs all the juice for itself, so trying to take power from the USB ports makes it flaky. There are many reports about this on the forums and on the web. I *highly* recommend using a powered hub with the Raspberry Pi. If you need to, you can use a 5V switching regulator or UBEC to power the hub from a battery. That's what I did before I gave up on the Pi and went with a Zotac AD-11.

[KevinO]

Are you running Linux on the Zotac? I've been looking at those. It is 4"x4" right?