# Robot controller crashes when using \\Conc movements

**URL:** <https://tech-community.robotics.abb.com/t/robot-controller-crashes-when-using-conc-movements/11624>\
**Category:** RAPID Programming\
**Created:** [September 22, 2024, 10:36pm UTC](https://tech-community.robotics.abb.com/t/robot-controller-crashes-when-using-conc-movements/11624 "2024-09-22T22:36:12Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![sparkeyepw](https://avatars.discourse-cdn.com/v4/letter/s/ecc23a/32.png) [@sparkeyepw](https://tech-community.robotics.abb.com/u/sparkeyepw)\
**Post date:** [September 22, 2024, 10:36pm UTC](https://tech-community.robotics.abb.com/t/robot-controller-crashes-when-using-conc-movements/11624/1 "2024-09-22T22:36:12Z")

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I’m using the IRB660 and trying to execute non-blocking movements, but when attempted the robot controller crashes after the first movement and locks the joints.

My only hint is that a joint position error is throw for joint rob1\_1 being too far from the ordered position.

Example:

MoveL \Conc, pPos1, speed, z100, tTool;  
MoveL \Conc, pPos2, speed, z100, tTool;

I’m sending less than 5 movement commands back to back. Has anyone run into this?

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**Author:** ![graemepaulin](https://avatars.discourse-cdn.com/v4/letter/g/258eb7/32.png) [@graemepaulin](https://tech-community.robotics.abb.com/u/graemepaulin)\
**Post date:** [September 23, 2024, 11:44pm UTC](https://tech-community.robotics.abb.com/t/robot-controller-crashes-when-using-conc-movements/11624/2 "2024-09-23T23:44:35Z")

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If you remove the \conc argument from all of the move commands giving the issue do you still get an error?

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**Author:** ![SomeTekk](https://dub1.discourse-cdn.com/flex005/user_avatar/tech-community.robotics.abb.com/sometekk/32/151_2.png) [@SomeTekk](https://tech-community.robotics.abb.com/u/SomeTekk)\
**Post date:** [September 30, 2024, 8:29am UTC](https://tech-community.robotics.abb.com/t/robot-controller-crashes-when-using-conc-movements/11624/3 "2024-09-30T08:29:07Z")

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Per the RAPID Overview manual the concurrent switch for motion commands is for logical instructions e.g. IO instructions.  
It is suspected the manipulator’s motion planner would be overtaxed trying to interpolate multiple paths simultaneously.