Get actual Euler and Quaternion angles

RAPID Programming
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1

Hello,

I have a list of targets(Targets 001-127), and I have a TRAP routine set up to constantly update and print out the position (X,Y,Z) of the robot, even while it is in the middle of a move. My question is, can I also update and print out the current Euler and Quaternion Angles, even while the robot is moving? I am updating the status 10 times a second, and I am trying to compare the commanded vs. actual for position and the angles. I got the position part, just not sure what to do about the angles?

Thanks for any help,
SM

2

Yes, you can use the RAPID function CRobT, which “returns a robtarget value with position (x, y, z), orientation (q1 … q4), robot axes configuration, and external axes position.” It would then be straightforward to convert the orientations into Euler angles, if required.

3

jsph,

Thank you for your reply. I am using CRobT just like you said. I am trying to send the data as a string to LabVIEW via sockets. I get an error saying that the string is too long. How can I break the data into multiple strings, 1 string for position, 1 string for quaternions, etc.?

Also, how can I parse the Quaternion angles and then convert to Euler angles?

Thanks for the help!
SM

4

Or is there a way to eliminate some of the values from CRobT, such as the External Axes values or Axis Configurations? That would shorten the string.

Thanks,
SM

5

You can access each component of the the RobTarget record before converting to a string, which will result in shorter stings.

In the header, add:

VAR robtarget currentRT;
VAR string posStr;
VAR string orientStr;
VAR string confdataStr;
VAR string extjointStr;

In the procedure, add:

currentRT := CRobT(\Tool:=tool0 \WObj:=wobj0); !read current robtarget
posStr:=ValToStr(currentRT.trans); !current robot position
orientStr:=ValToStr(currentRT.rot); !current robot orientation
confdataStr:=ValToStr(currentRT.robconf); !current robot configuration
extjointStr:=ValToStr(currentRT.extax); !current external axis position

Or you could go even further down, if required, e.g.

xStr := NumToStr(currentRT.trans.x,3);

The function EulerZYX can into an Euler angle component from an orient-type variable.

anglex := EulerZYX(\X, currentRT.rot);
angley := EulerZYX(\Y, currentRT.rot);
anglez := EulerZYX(\Z, currentRT.rot);

These nums could then be converted to strings and concatenated if you wish, although I would be temped to do the conversion to Euler angles in LabVIEW or even in Excel after recording the data.

Hope this helps. Note, the code is untested.

Regards,
Joseph