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Help for Understanding Rx, Ry, Rz position in (Universal Robot) 
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/ Most recent by VT_340
in Programming

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VT_340
Posts: 23 Apprentice
in Programming
Hi!
I need a bit of help in understanding how the tool orientation in space is described. I think it is straight forward to understand that XYZ coordinates define a point in space. But how to understand the three coordinates that comes next in a pose? I already read the Axis–angle representation article in Wikipedia and watched a video but yeah.. are there any other explanations? Would be Interesting for example how to calculate all three values in way that the toolhead is just rotating for example. Thanks in advance,
Hans
Hans
Best Answer

louis_bergeron Posts: 91 HandyHans,I can understand you, rotation vector Rx,Ry,Rz is not an intuitive way to represent orientation. If you would like to calculate orientation programmatically, I will suggest you working in RPY representation and let the controller calculate the rotation vector for you. RPY is a more intuitive and methodologic way to calculate an orientation. Once you have calculated an orientation, You can use script function rotvec2rpy(rotation vector) and rpy2rotvec(rpy vector) to switch from one representation to the other.You can also use the function pose_trans(p from, p from to) to rotate a calculated position around an axis.Regards
Unfortunately in Version 1.8 of URScript this function does not exist. As far as I know thats the latest software that runs on our machine. Thank you anyway.