Relative waypoint

General Application Help: How do I?
1

Hi everyone,

I’m currently working on a project where I constantly need to do the same relative moment.
The robot (UR5) moves to waypoint_1A, which is a fixed position, then I move him with a relative movement to waypoint_1B. Now for 10 positions i need that same relative movement. So when the robot goes to the next waypoint_2A = fixed it needs to do the same movement. Now here is the problem: that same movement I used in waypoint_1B I want to reuse. So I create a new waypoint_2B, I set the robot to the same position as in waypoint_1B and teach him to this point. Now when I do this and let the robot do the movements, it just goes back to the first point instead of just doing the same relative movement. Can anybody say what I’m doing wrong and how to fix this?

Thanks in advance!

Screenshot 2022-04-14 133739
Screenshot 2022-04-14 1337391872×855 159 KB

2

You should be able to just copy/paste “ Waypoint_1B” and it will perform the same relative motion as before. I’m not 100% sure what goes on under the hood for Relative waypoints but best practice I’ve noticed is set the “ from point” to your last travel position.

For example:
Let’s say I’m programming the same program you are

  1. I grab robot move it to position then hit “Set waypoint_1A”
  2. I add waypoint but change it to “relative”
  3. Now without moving the robot I hit “from point” and “Set waypoin_1Bt” (haven’t moved robot position)
  4. Now moving robot to some relative position I set the “to point” and “Set waypoint_1B”
  5. I move robot to new position and program position A2
  6. I create new waypoint and change it to “relative”
  7. Now moving robot back to 1B position I save this as “from point” waypoint B2 (this creates an offset at the start of the relative move and will result in the motion you are seeing where it returns to waypoint_1B)

I would recommend copy/pasting your waypoint_1B relative move after going to position 2A.

I could be wrong though and someone else in the URcommunity might have a better answer. Hope this helps and best of luck!

3

First of all thank you for your reply.

But the way you describe it is exactly what I did and still without any results. The robot always goes back to the first relative position instead of just doing the same movement at another point.
Today I tried it again starting from scratch but still with the same issues as before…

4

Just to clarify, it’s moving to the wrong position when you press Play, or when you hold the Move To button to jog the robot to the position?

5

It moves to the wrong position when I hold the Auto move button. I haven’t tried playing the full program.

6

Tap the line number after the relative move (so the robot will pause after it’s done), and then choose to “Play From” the move that you’ve made relative. My guess is it will move as you expect.

This is the problem I’ve always had with relative waypoints. They are stored to the node as a Fixed position. This has to do with the different methods called when using Move To vs pressing play. It makes it very cumbersome to program large jobs with, as the only real way to through these motions is to do as I’ve described: Pause after the move, and choose “Play From” the line right before. Which means you also have to comment out any moves in the Before Start sequence I think, as it still wants to run those.

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