BJR

sequential MAM moves

7 posts in this topic

I am going over someone else's program making a few changes and double checking what they did.  I always use .PC to determine when an MAM has completed.  He has used some LIM commands corresponding to finding a small limit around the .actualPosition and comparing what the commanded position was which is probably OK too.

But then I ran across what seems to be one move followed by another move in the other direction and nothing really being monitored to know when to make the second MAM other than a small timer.  Since the machine runs flawlessly for the last few years I am wondering how the MAM command works with regards as to what I will imagine is like a buffering characteristic. 

 

******If the program is in fact making a small MAM move then, without confirming it is complete, making another MAM on the same axis before the first motion actually completed what would it naturally do?  I'm guessing by the way the machine runs ok, it just buffers the second command because it is busy with the first.  I am surprised it does not interrupt the first move and issue an axis error or at least stop that first motion.  What would you expect it to do based on how MAM works? 

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Depends on the parameters of the instruction. IIRC, you can set the move to either take over the axis, add to the axis, or go into the execution buffer pending completion of the previous move.

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5 hours ago, JRoss said:

Depends on the parameters of the instruction. IIRC, you can set the move to either take over the axis, add to the axis, or go into the execution buffer pending completion of the previous move.

I suspected that the answer would depend on something but didn't know enough where to look for any related options or parameters.  Thanks for the response.  I will check out the MAM setup for those two moves...

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The settings I'm referring to are hidden by default. To see them, you have to expand the MAM block. There should be a little arrow in the bottom corner. The help manual gives you an idea of what they do. If you post a screenshot of the expanded MAM blocks, I can help you figure out what they're set up to do.

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It comes under the pending part of the instruction, this determines how it reacts when they overlap. If you got to intstruction help it gives an overview of what each value will give you.

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On 22/08/2016 at 2:03 AM, BJR said:

I am going over someone else's program making a few changes and double checking what they did.  I always use .PC to determine when an MAM has completed.  He has used some LIM commands corresponding to finding a small limit around the .actualPosition and comparing what the commanded position was which is probably OK too.

 

The .PC (process complete) status for MAM indicates that moving of the axis command position has finished. It does not indicate that the axis has reached the desired position. But rather than using LIM compares on actual position, use the axis position lock status. Set the axis position lock tolerance in the axis tag.

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On ‎8‎/‎24‎/‎2016 at 9:04 AM, JRoss said:

The settings I'm referring to are hidden by default. To see them, you have to expand the MAM block. There should be a little arrow in the bottom corner. The help manual gives you an idea of what they do. If you post a screenshot of the expanded MAM blocks, I can help you figure out what they're set up to do.

Thank you all for the suggestions.  I will not have time to make improvements for a week or two but appreciate the lessons! 

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