View Full Version : NOMAD: Quadruped for the games

10-31-2012, 12:53 PM
Got the Quad kit from Trossen the other day. Opened the box and laid the parts out for a head count to make sure all was there.


WoooHooo! Now on to the good stuff. Following the instructions, etc. it took about 4.75 hours to build the Quad. No testing or programming has been done yet, just a build out.

The build was fairly straight forward, though I did run into a few snags along the way.

Next step is pairing the xbees and programming to getting the quad to walk and then building out the cannons, etc. The bots "shell" is not fully buttoned up yet (just the two mounts), so I can open it to access the arduino and xbees and battery.


Bots name: NOMAD

10-31-2012, 03:12 PM
Care to elaborate on the snags you ran into? Always looking for feedback to improve our instructions. If you don't want to pollute your build thread feel free to shoot me an email/PM.

11-16-2012, 11:28 PM
Finally had time to work on NOMAD this evening. The pic below is posed with the gun turret mounted...I should have some videos of NOMAD walking around soon.


11-19-2012, 07:14 PM
NOMAD's first steps...

Not sure what the problem might be. I checked all the fittings, verified the construction of the framework, servos, etc against the instructions again. Tightened up anything lose.

If anyone has any ideas I would welcome the input!



11-20-2012, 10:00 AM
I don't know how much of the software is set up by the user, but I would try making the leg length in software shorter, i.e. make the point of contact of the feet closer to the body. You will need to do this anyways once you add the turret, because that extra weight is just going to cause problems with the legs.

11-20-2012, 11:19 AM
I am probably not the best one to answer this as I have not done any work on a quad, but have done quite a bit with hexapods. But I do remember that Zenta(Kåre) used to have a hexapod that he developed, that he modified the Phoenix code originally developed by Xan (Jeroen Janssen ) to work with his quad. I believe part of the modifications was to shift the Center of Gravity with each part of the walking gait. I believe there is more information up in the Lynxmotion thread (http://www.lynxmotion.net/viewtopic.php?f=8&t=3967), especially around page 4. I believe that a lot of the other people that did quads after that based a lot of their work on this as well.

The original code for this was developed in basic for processors built by Basic Micro (Bap28/Arc32). While I have ported the Phoenix code over to C and run on several platforms including the Arbotix/Arduino, I have not integrated any of these changes into that code base.

I don't know if any of the COG modifications were put into the PhantomX code base or not. If so, it may need to be tweaked as the extra weight of your turret.

I agree with Getlex that you may want to try modifications of the how far each step tries to take as well as the initial positions and the like.

Good Luck

11-21-2012, 07:27 PM
Also, you should answer Tyberius' question, and then bug him some more... He's the guy selling you the kit you built :)

(Edit: That's assuming you didn't PM/email him already; If so carry on!)

12-06-2012, 05:08 PM
Please contact me via PM or email (found on our contact page). Something is definitely not right here, the latest code drop I have verified on our in-house quad and it's not having these stability issues. Need some communication in order to help though. :)

One thing to clarify: You can't just go 0-100% on the throttle. You have to ease into moving forward, this is because it's setup to go the maximum speed that is stable on that quadruped and the IK engine reacts VERY quickly.