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sturkel
Joined: 05 Jun 2008 Posts: 5
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Posted: Tue Jun 17, 2008 7:09 am Post subject: Problem with photoeyes |
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When I have a photoeye positioned between 2 conveyors (small distance between them) and the beam of the photoeye is not located above one of them, the photoeye is not triggered.
Does someone have a solution for this problem?
This problem also appears at composed conveyors. |
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johngibbons
Joined: 14 Mar 2008 Posts: 21 Location: Holland, MI
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Posted: Wed Jun 18, 2008 11:59 am Post subject: |
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The load on conveyor travels above the conveyor so if the photoeye is at or below the conveyor level it will not be triggered. I would put the photoeye 3 inches above - assuming your loads are 6 inches tall. If you are moving extremely short loads - say less than 3 inches then I would have the photoeye pierce the plane of the conveyor at the middle. Say - 3 inches height below and + 3 inches height above.
Let me know if you are still having issues...
John _________________ John Gibbons
LinkedIn Profile http://www.linkedin.com/in/johngibbons1 |
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sturkel
Joined: 05 Jun 2008 Posts: 5
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Posted: Wed Jun 18, 2008 1:33 pm Post subject: |
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| johngibbons wrote: | The load on conveyor travels above the conveyor so if the photoeye is at or below the conveyor level it will not be triggered. I would put the photoeye 3 inches above - assuming your loads are 6 inches tall. If you are moving extremely short loads - say less than 3 inches then I would have the photoeye pierce the plane of the conveyor at the middle. Say - 3 inches height below and + 3 inches height above.
Let me know if you are still having issues...
John |
The problem is not that the photoeye is under or inside the conveyor, but it's exactly located above the edge of the conveyor pieces (arc and straight)
| Code: |
CONVSECTION name sec1 type DefaultSection width 1 Meters vel 1.9 Meters Seconds acc 4 Meters Seconds Seconds dec 4 Meters Seconds Seconds
piece cenx 259.922 ceny 92.71 cenz -6.825 begx 258.481 begy 90.982 begz -6.825 upz 1 angle 300
piece begx 259.539 begy 90.493 begz -6.825 endx 260.721 endy 90.289 endz -6.825 upz 1
CONVPHOTOEYE name PEC1 type DefaultPhotoeye blocktimeout 0.001 Seconds cleartimeout 0.001 Seconds begx 259.6236887 begy 90.98562093 begz -6.785 endx 259.4532244 endy 90.00025709 endz -6.785
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I hope that I make the problem clear with the content posted above. |
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johngibbons
Joined: 14 Mar 2008 Posts: 21 Location: Holland, MI
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Posted: Sat Jun 21, 2008 4:08 pm Post subject: |
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When you run the model do loads travel on top edge of conveyor? I have seen instances where plane flips and loads gravel on bottom of conveyor for 1 section. Then after that they travel on top. If this is happening either delete and redrawn or carefully flip section over - sometimes a mirror flip is needed. _________________ John Gibbons
LinkedIn Profile http://www.linkedin.com/in/johngibbons1 |
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sturkel
Joined: 05 Jun 2008 Posts: 5
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Posted: Mon Jun 23, 2008 6:49 am Post subject: |
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| johngibbons wrote: | | When you run the model do loads travel on top edge of conveyor? I have seen instances where plane flips and loads gravel on bottom of conveyor for 1 section. Then after that they travel on top. If this is happening either delete and redrawn or carefully flip section over - sometimes a mirror flip is needed. |
You're answer is not totally clear for me.
Do you mean that the load travels on the top site of the conveyor on the screen and 'internally' moves on the downside?
Could you explain the scenario that when I move the photoeye 1cm in x or y direction the cell works perfect?
thanks in advance
note: did you tried to reproduce it with the code above? |
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johngibbons
Joined: 14 Mar 2008 Posts: 21 Location: Holland, MI
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Posted: Mon Jun 23, 2008 6:53 pm Post subject: |
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if you want you could send your model/workin portion to my email and I'll take a quick look. cant quite see all of model in snipet of conveyor arc you posted.
automod does from time to time "flip" a section over 180 in z direction. this will cause a load to travel on bottom not top of conveyor. _________________ John Gibbons
LinkedIn Profile http://www.linkedin.com/in/johngibbons1 |
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sturkel
Joined: 05 Jun 2008 Posts: 5
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Posted: Tue Jun 24, 2008 10:02 am Post subject: |
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| johngibbons wrote: | if you want you could send your model/workin portion to my email and I'll take a quick look. cant quite see all of model in snipet of conveyor arc you posted.
automod does from time to time "flip" a section over 180 in z direction. this will cause a load to travel on bottom not top of conveyor. |
I tried to make a project to demonstrate the problem.
The project can be downloaded at
http://home.ict.nl/~dminderh/test.arc.zip
I put the pec (pec1) on the actual position and pec2 under the conveyor.
both pecs are not triggered.
when i move the endy of pec1 1 centimeter (from 90.00025709 to 90.01025709) the pec is triggered correct.
I hope someone have a solution for this problem. |
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johngibbons
Joined: 14 Mar 2008 Posts: 21 Location: Holland, MI
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Posted: Wed Jun 25, 2008 8:03 pm Post subject: |
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I got PEC1 to work. I think you issue is placement of photoeye smack dab on edge of conveyor. I moved coordinates to 259.7, 91.25 (X,Y) and 259.4,89.75 (X,Y) and photo started working as expected.
The 2nd photo PEC2 is at or below edge of conveyor.
I know its bad form to have a photo, station, transfer, at same point. So you should use 1 photo to do 2 things. Not 2 photos in same location....
Hope this helps.
John _________________ John Gibbons
LinkedIn Profile http://www.linkedin.com/in/johngibbons1 |
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sturkel
Joined: 05 Jun 2008 Posts: 5
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Posted: Wed Jun 25, 2008 8:32 pm Post subject: |
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| johngibbons wrote: | I got PEC1 to work. I think you issue is placement of photoeye smack dab on edge of conveyor. I moved coordinates to 259.7, 91.25 (X,Y) and 259.4,89.75 (X,Y) and photo started working as expected.
The 2nd photo PEC2 is at or below edge of conveyor.
I know its bad form to have a photo, station, transfer, at same point. So you should use 1 photo to do 2 things. Not 2 photos in same location....
Hope this helps.
John |
Thats what I said, Pec1 works when I move the coordinates, but that means that the pec is not at the 'real' position.
I like to annalyse the problem why the pec don't work on that location, so I can solve this.
It's possible to create a workaround (move a couple of centimeters), but I hope to get this to work with the 'real' position.
Do you have a solution other then move the pec? |
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johngibbons
Joined: 14 Mar 2008 Posts: 21 Location: Holland, MI
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Posted: Thu Jun 26, 2008 12:33 pm Post subject: |
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I fail to see issue if you move start and end points of photoeye off edge of conveyor - the beam of photoeye is still in the same spot.
As far as height of the photoeye off conveyor, unless your sorting mail and or dvds it shouldnt matter if its just above plane of conveyor.
Alot of times people model photoeyes with stations, they take less overhead and loads always pass over them.
Hope this helps.
John _________________ John Gibbons
LinkedIn Profile http://www.linkedin.com/in/johngibbons1 |
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