[kovaley]

Hi,
I’m encountering a performance issue in RoboDK V5.4.0 (also tested on V5.9).
When adding a large number of targets in a station with a synchronized linear axis, the simulation speed drops drastically, even when the targets are not set to visible. I understand that rendering performance may decrease due to a large number of items, but what seems odd is the FPS drop and simulation slowdown despite the items not being rendered.
To investigate, I created a simple cell with a linear axis and a short program looping through three points multiple times. I then added several thousand targets (set to not visible) to simulate my use case and compared the performance with and without these targets :
  linAxis.rdk (Size: 3.14 MB / Downloads: 65) .
Here’s what I observed:

• Regular Simulation Speed: The bloated station moves very jerkily, while the same station without the additional targets runs smoothly. Interestingly, both stations maintain the same program speed.
  
• Fast Simulation Speed: The bloated station becomes not only jerky but also noticeably slower than the unbloated one.
  

To narrow down the cause, I removed the linear rail, leaving only the robot :
  robot.rdk (Size: 1.97 MB / Downloads: 58) . 
Surprisingly, the issue disappeared; the robot-only station performed smoothly, even with the large number of hidden targets.
I’d appreciate any insights or suggestions you may have.

[Albert]

It is slightly more complex to calculate the kinematics when you have a synchronized rail with a robot arm compared to when you have a robot arm alone.

However, the real issue with the project is that you have many targets linked to the robot (inside your bloat reference frame) which takes time to calculate the reachability warning flag. If you delete these targets it works much faster.

In any case, we'll try to add an option to prevent forcing this reachability refresh flag which slow things down.

Also, a quick workaround if you use the API would be to unlink those targets so they are not linked to the robot.

[kovaley]

It totally makes sense!
The reachability warning feature is really nice when moving things around and testing the reach, but it’s a bit useless while you run program simulations. I wouldn’t mind being able to turn it off manually or if the recalculation was turned off when a program is running.
Merci!

[Albert]

We just published an update that fixes this performance issue. This issue was specific to using a lot of targets linked to a system of a robot plus an external axis. There is no need to change any settings.

You can take the latest version of RoboDK here:
https://robodk.com/download

[kovaley]

I downloaded the last version but there was no increment from the version I already had... it was still v5.9.0.25039 and it still has the performance issue.

I also experimented with the API to try unlinking the targets, but there doesn’t seem to be a function for that. From what I observed, once a target is linked to a robot, the only available option is to change the robot it’s linked to. Maybe I'm missing something?

In any case, I worked around the issue by importing a dummy SCARA robot in my station and modifying the View Utilities script to change the target link to it when I hide them and back to my kuka robot when I show them.

Thanks!

[Albert]

I tried reproducing the update on a new computer and it works.

Can you provide a print screen of the Help-About menu? It should say the build date is today (February 19th), with a newer build number. This is a new version even if the name of the installer is the same.

I agree that having the same installer name can be misleading. We'll prevent this confusion in the future.

[kovaley]

I just tried a fresh download (and I'm sure I did not use the old installer downloaded a few days ago) and a fresh install in another drive of my computer and get a build date of 2025-01-28. I still have my v5.4 installed in another drive if it's relevant.

[Albert]

OK the problem should be fixed now. You should now see the correct build number of RoboDK on the installer: 
Install-RoboDK-64-v5.9.0.25130.exe.

There was a cache issue with the download that should be fixed now.

[kovaley]

Everything is working now,
thanks!

[Albert]

Perfect, thank you for your feedback!