ABB Quaternion Result

[Rob Cooke]

Good day,

I have a tool.... 2 grippers that are offset (+/-45deg) from Y and 15 deg from Z

(Rx=0, Ry=17.5, Rz=15)
(Rx=0, Ry=-17.5, Rz=15)

this is how I would define in a Motoman controller  (to give better understanding)

I am trying to use this conversion program that I found in another post but it does not work for me....

Robot is telling me invalid data for component tframe.rot!

My ABB Quaternion Result is [0.98, -0.02, 0.151, 0.129]


Please help.... I am missing something... Is there not an easier way?


PS: cannot use the 4 point teaching method

[Midwest Tech]

First thing you could try is the 6 point method to teach the TCP.

Otherwise, you could make a routine to assign the values using OrientZYX. Something like this:

PROC rTCP()

  !Assign TCP values
  tGrip1.tframe.rot=:OrientZYX(15,17.5,0);
  tGrip2.tframe.rot=:OrientZYX(15,-17.5,0);

ENDPROC

[prnuk2003]

For (Rx=0, Ry=17.5, Rz=15)  I get
q1 0.9799 q2 0.0199 q3 0.1508 q4 0.1290

and

(Rx=0, Ry=-17.5, Rz=15)
q1 0.9799 q2 -0.0199 q3 -0.1508 q4 0.1290

What code are you using for the calculation?

Have you used the RelTool instruction with the rXrYrZ component but then as MidWest Tech said you would need to define the tool with the TCP x and z method

[bert]

Are you using this tool http://www.robot-forum.com/robotforum/kuka_robot_forum/angles_conversion-t1284.0.html;msg4875#msg4875 ?

I checked, and the answer is correct. Maybe you need some more decimal places for the robot to accept that it's a valid quaternion. I don't have an ABB robot at the moment to check, but to 5 decimal places the values are [0.97991, -0.01986, 0.15082, 0.12901] for [0, 17.5, 15] XYZ fixed angles.

Edit: Sorry prnuk2003, I didn't see your reply. I had the reply window open for a while before I hit 'Post'

[Rob Cooke]

Thanks for replies....

I used the OrientZYX to get my Quats...

as a result I get up to 7 decimal places (in q2) which may be why the  ABB Quaternion Result [0.98, -0.02, 0.151, 0.129] was not excepted


All is good now!

Thanks again.

[basbasan]

whats roll pitch yaw and how i will order angles for abb robots. can anyone tell me pls

[tomC]

@basbasan:
yaw,pitch,roll is rotation around z,y,x? axis (you'll have to verify the order)


I really like Martin Bakers website for a math references.  He has a quaternion calculator and lots of info in general.
http://www.euclideanspace.com/maths/algebra/realNormedAlgebra/quaternions/index.htm