Could you use pressure mats?
I'm trying to find a good PIR presence sensor suitable to mount in a lift to detect if anyone is inside the lift.
The purpose is so that if someone is in the lift, the it will lock out all of the call buttons on the other levels.... this will prevent someone in the lift going to a level they should be etc etc....
Anyway we've tried a 360degree PIR which does the trick but if you stop moving, the PIR stops detecting after a few seconds...I can extend the time-out a bit but that still won't be suitable.
I got an Auto door presense sensor from Dorma, the theory behind it is good, it learns the area..... You can set it to learn for 1 minute or 10 minutes... Its pretty hard to stand still for a minute or 10 minutes so it would be good but the range isn't good enough... this thing is designed for looking straight down, it only reaches 86cm in front if I'm lucky. We could put two but still there is positential that if you stand in the middle between the two, then it won't detect....
So I'm looking for a PIR or some kind of sensor that has a bigger range and can learn the area....
Any help would be most appreciated.
Thanks
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Could you use pressure mats?
is there access control in the lift already?
Pressure mats suck, they are N/O and will wear out, not designed for commercial applications, imagine the traffic in a lift.
Good idea thou..
Still, whats the basic idea, if there is a card reader in the lift ?
This is a high security building (airport).
To answer the questions:
Its more of a goods lift so a pressure mat would be out of the question...too much wear ant tear, trip hazards etc... needs to be a sensor.
There is a card reader on each level to call the lift
There is a card reader inside the lift.
I don't actually have the full scope of this lift yet but I'll give a senario, if someone gets into the lift on say Ground floor, they swipe their card to go to Level 3. On the way up though, someone could call the lift on level 2. But the person in the lift isn't supposed to be allowed to get out on level 2. Or the person getting in on level 2 isn't supposed to be allowed to go to level 3.
So the intention is, when someone gets in on Ground level in this example, the PIR should detect someone is in the lift and will lock out all the call buttons/readers on the other levels until that person gets out.
We only control the access and can enable/disable the card readers, but we have no other interface to the lifts. You would think that the lift people might be able to put some programming in there system so that if someone gets in on ground and presses level 3, that the lift will go there and not stop even if someone presses another level. But I think its up to us eto do the logic..
We have it in other lifts but that cost tens of thousands of dollars and involved about 20-30 sensors along each side of the lift... I think thats a bit of an overkill......
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Last edited by Chimp; 02-10-08 at 09:44 PM.
i would have thought that a high level interface to the lift would have done the job, but really, the lift company needs to set the lift up for you.
If this is a high security issue, government or what ever.. money should not present an issue.
hang on, if you have readers outside and inside the lift, the outside lift readers control the call buttons on each level, there would be a way to disable those if the lift has already been called.
Maybe a timing thing ? would piss people off though.. swiping and not being allowed to call the lift..
In that case, the DVR used should have video analytics added to it. Install a camera, using the video analytics software you should be able to monitor that area, the rest is pure logic control. If area is occupied without valid card swipe, halt movement. If area is breached and valid card presented allow access.
Further reading of your earlier post has cleared this up, to achieve what you want, it can be done but depends on what system it is. I have done a job similar to this, required a lot of inputs, outputs, door interlocking, calculated auxiliaries the works.
Basically first person who calls the lift, disables all other readers/call buttons from accessing the system until that person get to the destination. But like I said, the lift won't stop anywhere and the person in the lift can only select one floor. If you are familiar with concept, we used function zones, calcs, relays, timers and interlocking and anti-passback.
Analytics Would be good if you have the DVR and the Cash for it, How about doing this :-
Outside the lift, there is a prox, you badge the prox and it allows you to get into the lift, that is all.
You get into the lift, All buttons except for ground are locked out 24/7, you badge your card and it free's the floors your allowed into, then using button feedback (You're going to have to get the lift guys involved) you can keep a track of where they went/which floor they went to.
Quick and easy, if you dont have the cables for the work, consider this, put the equipment in the lift car, 99% of Lift guys will do this for you, and you can use the reader cable that you did have for the LAN Wiring... and Lifts have 240V's for you to use.
Then if you really feel like it you can start to get carried away with timezone controls etc, for example :-
If the user badges at the outside reader, it opens the door and qualifies and Timezone for 60 Seconds, If the timezone is qualified and it recieves another badge from the internal reader, but no button feedback, drive an alarm, if a badge is recieved from the outside and not the inside, drive an alarm... there is lots you can do to make it more secure, just got to think sideways...
But yes, George has a point If they have the cash and the equipment (Indigeovision Analytics are soo cool! even DVTEL is okay !!) Hook this up to the alarm to help qualify use, your not going to stop people 100% of the time, unless you put access control doors on the other side of the lift (in the goods lift foyers put doors as well) so even if they get out at the floors, they need to get through more doors, and if your manpower chap/chappettes are awake they will hopefully pick this up.
/2c
ReD
So far I'm still trying to get an exact scope of what they want and how they want it to work... At this stage all we know is the lift needs to have volumetric sensors in the lift.... (meaning a sensor to know if someone is in there) So no amount of programming or funky stuff can tell us this.... We don't want to have too much I/O from the lift to the access control because when something goes wrong, it makes troubleshooting harder, but we always get the finger pointed at us first. There are other options that could involve the lift but like I said we'd like to avoid going down that path... The customer has asked for these detectors in the lift... what they want to do with them isn't 100% confirmed yet. I think there are cameras in the lift as well but I don't think the analytics is good enough in our current version of software, after we upgrade we can do more... but that wont be till next year.... Problem is that it relies on the network functioning etc..
So back to my orginal problem... I really need to get a suitable sensor in there.....
I have seen somewhere a sensors that you used to install in a building and if any door opened or window opened it would acivate seem to work off air pressure dont know if this would help or if anyone knows are they still about
Really needs to detect a person within the area... not just a door opening/closing
Sounds like a new age security consultant is giving dumb advise hehe
Let us know how u go..
IR beams
Volumetric sensor is generally consultants talk for a PIR.
Ive used RCR-C Sentrol Radar in a lift before, however it was combined with a concept4000 doing full button control feedback.
The user had to swipe a card to enter lift. Doing so locked out other readers via a qualify aux and turned their LED red from green.
The user had to be seen to have exited the lift before other readers where reactivated. This was achieved with the RCR sensor and there was also an output from the lift to say it had stopped at a floor.
Private - And they worked inside a metal box without to many dramas?
We only used that detector as it was what the consultant asked for but it seems to work fine had no complaints in over a year.
It is set at the minimum distance of 3meters.
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