View Full Version : [Question(s)] Xan's Phoenix Code Clarification

08-13-2010, 06:52 PM
Hi All!

I have a few questions regarding Xan's Phoenix Code that I'm hoping you guys can clear up for me. It will be an integral part of my new hex so I need to be sure I understand it 100%

First Question: I have attached a picture of my in-progress hex chassis sans electronics. In the picture, I have labeled the front, center and rear of he hexapod in blue (along with the center lines) and what I believe to be the correct labeling of her parts and distances in red. What I want to make sure of is that I am measuring the correct distances to work with his code, and that I have my labels correct. Just for clarification, the RFPosX, RFPosY, and RFPosZ in the picture are referring to the foot tip.

If I have this right, the X offset for the right front coxa should be a negative value. Also, I'm being thrown a bit by the Z axis in the code... Should the Z axis be the height (off the ground) of the point of rotation for the coxa or do I have it right in the picture?Is all of this correct?

Second Question: All of his measurements are done in millimeters, right? Also, his angles are in degrees?

Third Question: I feel kind-of stupid asking this one, but better to ask and know than not ask and not know... As near as I can tell (and if I have my picture right), the global XYZ system and the local (at the foot point) XYZ system are shifted, in that Y becomes Z for the foot. Am I way off base in this or am I correct?

Thanks in advance for the help!


*Edit*: It has occurred to me that I may not have been very clear in my first question as far as where in Xan's code I am referring to... The labels "RFOffsetX" and "RFOffsetZ" I am referring to are in the "BODY DIMENSIONS" portion of Xan's code and the foot position is referring to the initial leg placement coordinates portion.

08-14-2010, 05:01 PM
Question 1: The sketch is right.

Question 2: Yes in mm and degrees.

Question 3: I believe your right on this aswell.

Ill check my version since I did a port aswell.

08-14-2010, 06:07 PM
Thanks Quantum! I really appreciate you taking the time to help me out with this!

I'm porting this code to an ARC-32, with the goal of removing PS2 control and having the micro interpret commands directly from a server application running on my laptop. What did you port you port this to?

08-15-2010, 09:10 AM
FYI - I previously ported the phoenix code over to the Arc32 and have uploaded code on the Lynxmotion site. You can find more information up on the thread: http://www.lynxmotion.net/viewtopic.php?f=8&t=6042


08-15-2010, 04:59 PM
Thanks Kurt! That is an incredibly informative thread, and is a significant help. It covers many of the issues I am tackling now. I might have some questions for you- I hope you don't mind if I pester you with them :)

08-15-2010, 10:11 PM
You are welcome. I don't mind questions. As you can probably tell I monitor the threads over there much more than the ones here, but I do try to keep up...