Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

MoveJ Commands Generated by the URP Post Processor

#1
Dear Support Team,

I would like to inquire about the generation of MoveJ instructions by the Universal Robots URP post processor.
Environment:
  • Post Processor: Universal Robots URP
  • RoboDK Version: v6.0.4 (64-bit)
During program generation, MoveJ instructions are inserted in certain locations.
However, I have verified that the generated program still runs correctly even after manually removing those MoveJ instructions.


Therefore, I would like to understand the reason why these MoveJ instructions are being generated.
Could you please clarify:
  • Under what conditions the URP post processor inserts MoveJ commands
  • Whether these MoveJ commands are intended to ensure safety, reachability, or robot configuration consistency
  • Or whether unnecessary MoveJ commands may be generated in some cases

I have attached the relevant program for your review.
Thank you for your support.


Best regards,
Keisuke Sakai


Attached Files Thumbnail(s)
スクリーンショット 2026-08-19 085632.png   
#2
When you trigger movements using a MoveJ in a UR URP program (Universal Robots URP post processor), it inserts the raw script command "movej" because the URP format does not allow imposing a movement to a joint target. Instead, it may use the cartesian values at the same joint location which would convert that joint target into a Cartesian target.

This script provides a safe approach to make sure the same program you simulated in RoboDK runs exactly the same way in the real UR robot.

In general, it is a good practice to trigger a joint move at the top of the program to make sure you bring the robot joints to a safe state and unwind the joints/cables from previous program runs.
#3
Dear Support Team,

Thank you for your previous explanation regarding the MoveJ commands inserted by the Universal Robots URP post processor.


Based on your explanation, I understand that MoveJ commands may be inserted to preserve the robot configuration and ensure that the real robot follows the same joint posture as the RoboDK simulation.


However, for our application, we would like to operate the program on the real robot using waypoint-based movements only, without the additional MoveJ commands generated by the post processor.


Could you please advise:

  1. Is it possible to generate a URP program using only waypoints and without the inserted MoveJ commands?
  2. If so, what would be the recommended workflow or settings in RoboDK to achieve this?
  3. Are there any precautions or limitations we should be aware of when using waypoint-only movements, especially regarding robot configuration consistency between simulation and the real robot?

Thank you for your support.
Best regards,
Keisuke Sakai
#4
You can skip generating the script code for MoveJ commands by setting this variable in the post processor to True:
SKIP_MOVEJ = True
This will avoid generating script code for joint movements. Keep in mind this could make the robot move to a different joint turn compared to your simulation.

You can find more information about how to customize this post processor here:
https://robodk.com/post/Universal-Robots-URP

I'm sorry for the delays. Let us know if you need more information.
  




Users browsing this thread:
1 Guest(s)