# Error in get\_inverse\_kin, Runtime Error in URControl.log

**URL:** <https://forum.universal-robots.com/t/error-in-get-inverse-kin-runtime-error-in-urcontrol-log/12803>\
**Category:** Technical Questions\
**Created:** [March 8, 2021, 10:55am UTC](https://forum.universal-robots.com/t/error-in-get-inverse-kin-runtime-error-in-urcontrol-log/12803 "2021-03-08T10:55:43Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![csaba.mucsi](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.universal-robots.com/csaba.mucsi/32/277_2.png) [@csaba.mucsi](https://forum.universal-robots.com/u/csaba.mucsi)\
**Post date:** [March 8, 2021, 10:55am UTC](https://forum.universal-robots.com/t/error-in-get-inverse-kin-runtime-error-in-urcontrol-log/12803/1 "2021-03-08T10:55:43Z")

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Hello,

we are receiving an error popup as a result of a get\_inverse\_kin function on **one specific robot** and one specific position, while it works properly in a simulator.  
The position is not close to the robot reach limits and not close to any singularities either. It is a quite regular position and we don’t understand why we get this error.  
We are able to reproduce the error in URSim when using the same physical calibration data from the robot.  
In URControl.log we have discovered the following entries:

2021-03-08\_11:37:17:95469 00:04:03:322 INFO - get\_inverse\_kin target pose: [-0.357042, 1.017627, -0.129022, -1.195682, -2.900253, 0.001485]  
2021-03-08\_11:37:17:95473 00:04:03:322 INFO - get\_inverse\_kin target pose norm: 1.086136  
2021-03-08\_11:37:17:95473 00:04:03:322 INFO - get\_inverse\_kin qnear: [0.512249, -1.096430, 2.621763, -3.590033, -1.434567, 0.651568]  
2021-03-08\_11:37:17:95474 00:04:03:322 INFO - get\_inverse\_kin qnear pose: [-0.391083, -0.474128, -0.089977, 2.236784, 2.014546, -0.783590]  
2021-03-08\_11:37:17:95474 00:04:03:322 INFO - get\_inverse\_kin qnear pose norm: 0.621159  
2021-03-08\_11:37:17:95475 00:04:03:322 INFO - get\_inverse\_kin pose/qnear dist: 1.492654  
2021-03-08\_11:37:17:95475 00:04:03:322 ERROR - Runtime error (3466:14): The robot cannot reach the requested pose. Script function get\_inverse\_kin is unable to find an inverse kinematics solution.

The last line with “Runtime error” might be relevant.  
I can attach the physical calibration data on request.  
Polyscope version is 5.9.4

Thanks for any comments, suggestions.

Csaba

UPDATE:  
The error disappears when I change the parameters to  
maxPositionError=0.0005,  
maxOrientationError=0.0005,  
in get\_inverse\_kin().

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**Author:** ![Ebbe](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.universal-robots.com/ebbe/32/1413_2.png) [@Ebbe](https://forum.universal-robots.com/u/Ebbe)\
**Post date:** [March 10, 2021, 11:20am UTC](https://forum.universal-robots.com/t/error-in-get-inverse-kin-runtime-error-in-urcontrol-log/12803/2 "2021-03-10T11:20:16Z")

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Hi @csaba.mucsi,

Can you share the calibration file for the specific robot?

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<div class="post-metadata">

**Author:** ![csaba.mucsi](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.universal-robots.com/csaba.mucsi/32/277_2.png) [@csaba.mucsi](https://forum.universal-robots.com/u/csaba.mucsi)\
**Post date:** [March 10, 2021, 11:35am UTC](https://forum.universal-robots.com/t/error-in-get-inverse-kin-runtime-error-in-urcontrol-log/12803/3 "2021-03-10T11:35:16Z")

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[20205080096.zip](https://forum.universal-robots.com/uploads/short-url/7Um7TevOwImfNAZWUxa72iIhYVT.zip) (287.7 KB) attached is the calibration data of the robot where the error has been observed, thanks @Ebbe