System input for pp to main rejected

Joeri

Hello,

My goal is to simply move to program pointer back to the main routine after receiving a signal from the PLC, no matter what the robot is doing.

What is the best way to get this done? Right now I have tried to use the system inputs and linked that signal to the action "PP to main". However this always gets rejected by the controller.

lemster68

The program cannot be executing at the time that PPtoMain is given.  You must use the system input Stop, then PPtoMain.  BTW, I really do not like PPtoMain, that leaves you with a lot of things to do in a recovery scenario to make sure that you do not crash the robot.

Joeri

Hey @lemster68 thank you for your input. I agree with you that it is not a good looking solution. How would you solve it in a "Clean" way.

lemster68

That is going to be related to how complicated your cell is.  A whole bunch of areas, machines or maybe a simple pick and place.

jmf

If you can give some more info on what your system is required to do, we can assist better maybe someone has done something similar. 

Joeri

It is a very simple laser cell:

 2 in/output tables

1 stationary laser device in the middle of the two tables.

 

In each table the robot can pick two different type of parts and there are two different laser programs. The pick and drop programs for both parts are 99 percent identical.

 

They way I see it there are 3 zones

1.      Left table

2.      Right table

3.      Laser area

 

A recovery scenario is fairly easy since there is a lot of space.

For the tables a linear move upwards is enough to always be clear and for the laser zone it would be the opposite a linear move down.

From there the robot always has a clear path to his home pos

lemster68

Sounds pretty straightforward, you could use worldzones to figure out which area you are in.  Quite a few years ago, I was experimenting with the path recorder for recovery.  That would have worked nicely, but these cells had PLC logic that gave a PPtoMain.  When that happens, all recorded paths get discarded.  You could experiment with that for recovery, but be forewarned that you absolutely DO NOT want to use PPtoMain.

jmf

WorldZone would actually work better.