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Author Topic: Include an airlock in pathfinder  (Read 2756 times)

AUS-1

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Include an airlock in pathfinder
« on: June 02, 2013, 11:28:19 pm »

Hi,
I have a case where the egress route in a particular building includes an airlock, in which a only one door can be open at any one time. 
I have attached an image to this post to explain this. 
So in reality what will happen is that Door 1 will open, the airlock will fill with say 5 people, then Door 1 will close.  Door 2 will open once door 1 has closed and the occupants will continue walking.  This process repeats over until all occupants have passed through the airlock.
Is there any way to model this in pathfinder? :-\
Kind Regards,
Andrew Williams
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Charlie Thornton

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Re: Include an airlock in pathfinder
« Reply #1 on: June 03, 2013, 08:52:15 am »

Pathfinder 2012 has no *direct* way to script a room's door behavior based on the number of occupants inside. However, I think you might be able to fake it with an elevator.

You would need to shift one of the rooms slightly (e.g. 0.01 meters) to make the elevator system willing to connect. Don't go with something really small like 1 mm because it will introduce problems with tolerance. Then, add the elevator and tinker with the level data and door delays until you get what you want. I've included a simple example PTH file that you can use to experiment with the timings.

Note: This is not the intended use of the elevator system. This method has not been tested on any data at all.
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AUS-1

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Re: Include an airlock in pathfinder
« Reply #2 on: June 04, 2013, 10:03:13 pm »

Thanks for your reply, your test case does exactly what i was after. 
I have tried to replicate this however and i have a couple of errors which i cannot seem to fix.
First, only 1 person goes in the lift, and then the lift does not return to pick up the rest of the population.
Second, the person seems to exit the simulation immediately on leaving the lift rather than travelling to the nominated exit door.
I have attached my pathfinder file.  Any help/suggestions are greatly appreciated.
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Charlie Thornton

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Re: Include an airlock in pathfinder
« Reply #3 on: June 05, 2013, 08:56:58 am »

You've specified a nominal load that is small relative to the size of the room. The way the nominal load feature works is by artificially shrinking (or, in your case, enlarging) the occupant-occupant collision radius of occupants when they enter the elevator room. It works very well when the radius changes a little and very poorly when the radius increases a lot. In your model the first person walks in and he doesn't know to go to the corner opposite the door - leaving his hugely inflated bulk blocking the door to go in.

At the moment, Pathfinder only option to limit the number of people in a room is the collision radius based nominal load. If you want three people in the airlock, your best option is reduce the area of the room either directly or by adding some furniture. If pathfinder calculates that a radius factor of 1.0 will fit 3.4 occupants and you ask for 3.0, the resulting radius factor of 1.13 will work a lot better than the much bigger factor you are getting now.
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AUS-1

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Re: Include an airlock in pathfinder
« Reply #4 on: June 05, 2013, 11:38:11 pm »

Ok great, that makes sense.  Greatly appreciate your assistance.
Andrew.
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