Announcement

Collapse
No announcement yet.

Infrared Beam Sensors

Collapse
This topic is closed.
X
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    Infrared Beam Sensors

    Im thinking about installing two IR Beam sensors in the archway between rooms. My idea is to install them so that they will trigger a fraction of a second apart, in order to detect going in or out of the room.

    The neat thing about this is I could probably get a good idea of the number of people in a room, if they are really in there, and do much more than a motion sensor could do in managing the lights and Theater equipment.

    1. Are there (relatively inexpensive) devices that can do the job?
    2. Can they be connected to the SECU-16?
    3. Will I be able to measure direction, if these trigger within a fraction of a second (maybe as small as 20mS) of each other? This is probably an Ocelot/SECU-16 timing question. I suppose if the answer is no I could design a small logic board that can do this, but I'd rather not.

    Any comments? [img]/infopop/emoticons/icon_wink.gif[/img]

    -System Spec------
    ASUS A7V333ARU VIA KT333 MOTHERBOARD; AMD ATHLON XP PROCESSOR 2200+ (1800MHz); 1024MB DDR 333MHz DDRAM; ATI RAGE 128 CHIPSET 32MB W/ TV OUT VGA CARD; AHANIX PLATINUM XP SILVER/BLACK COLOR 9 DRIVE BAYS SPI 300W POWER SUPPLY TOOL-LESS PANELS ATX MID TOWER CASE; Win2K SP2 5Serial 1Parallel, Hawking Modem, Broadband >Mediacomm, Phillips Audio, ATT Voices, PhoneSwitch, 10/100 Ethernet, Ocelot for IR and Bobcats, CM11A for X10
    -------------
    GenevaDude

    #2
    If you don't mind using a soldering iron then try this:

    http://www.boondog.com/%5Ctutorials%5Cirled%5Cir.html

    I have not built one yet. If you do let me know how your solution works. I would love to do the same thing.

    Don't know if the Secu is fast enough though

    Rob

    Rob

    Comment


      #3
      RobM,

      Good find! The BOM is easy enough to get and it looks quite simple to build. This is going on my list of projects.

      I noticed some wall mount emmitters on SmartHome a while back. They're expensive but the plastic mount looks attractive. Maybe I could do something similar.


      Thanks! [img]/infopop/emoticons/icon_wink.gif[/img]

      -System Spec------
      ASUS A7V333ARU VIA KT333 MOTHERBOARD; AMD ATHLON XP PROCESSOR 2200+ (1800MHz); 1024MB DDR 333MHz DDRAM; ATI RAGE 128 CHIPSET 32MB W/ TV OUT VGA CARD; AHANIX PLATINUM XP SILVER/BLACK COLOR 9 DRIVE BAYS SPI 300W POWER SUPPLY TOOL-LESS PANELS ATX MID TOWER CASE; Win2K SP2 5Serial 1Parallel, Hawking Modem, Broadband >Mediacomm, Phillips Audio, ATT Voices, PhoneSwitch, 10/100 Ethernet, Ocelot for IR and Bobcats, CM11A for X10
      -------------
      GenevaDude

      Comment


        #4
        I would like to take a look but I can't get the link to work. any ideas?

        SteveD

        Comment


          #5
          You are right Steve. It worked the other day but today it's apparently not working. If it's a personal link, then his computer may be off-line or "stalled".

          -System Spec------
          ASUS A7V333ARU VIA KT333 MOTHERBOARD; AMD ATHLON XP PROCESSOR 2200+ (1800MHz); 1024MB DDR 333MHz DDRAM; ATI RAGE 128 CHIPSET 32MB W/ TV OUT VGA CARD; AHANIX PLATINUM XP SILVER/BLACK COLOR 9 DRIVE BAYS SPI 300W POWER SUPPLY TOOL-LESS PANELS ATX MID TOWER CASE; Win2K SP2 5Serial 1Parallel, Hawking Modem, Broadband >Mediacomm, Phillips Audio, ATT Voices, PhoneSwitch, 10/100 Ethernet, Ocelot for IR and Bobcats, CM11A for X10
          -------------
          GenevaDude

          Comment


            #6
            Thanka, I'll just keep trying. I'm still looking for a better low cost driveway sensor. The motion sensor has way too many false triggers in my application.

            SteveD

            Comment


              #7
              If you notice the guy on this site:-
              http://www.boondog.com/%5Ctutorials%5Cirled%5Cir.html
              is using the IR to monitor motor speed.
              I would be suprised if you could use this over the width of a driveway without some sort of lens at each end.
              I very much doubt if the SECU will be any where near fast enough to see somebody walk through the beam. In the real world I would use a High Speed Counter card into a PLC to ensure that the ON/OFF's are seen. Not the normal PLC I/P card. They work up to 100 kHz! I do not know what the scan speed of the SECU is. Also take the case of 2 people walking through with a very small space between them, will the system show one or two people? Driving a car through will probably be sensed due to the length of the car and the speed.
              A hardware solution is possible though.

              Comment


                #8
                My original thought was to add a 1-Wire DS2405 to his circuit. I use these now to monitor open/close state of a switch and have been pleasantly surprised with the response time. I can see where the distance across a driveway may be a problem but across a hallway would work?

                Could you elaborate on "High Speed Counter card into a PLC". Would this require a pc slot or serial port. How would it integrate to HomeSeer?

                SteveD

                Comment


                  #9
                  Sorry I should of explained a little more about High Speed Counter cards for PLC's. These are industrial Programable Logic Controllers and a means of getting high speed inputs/counts into a a slower scan rate PLC. There are cards on the market which will fit into a PCI slot of a standard PC but they are high cost and really for industrial use.
                  Using the 1-wire system is OK for monitoring contact open/closure, as this is slow speed, but I suspect the scan rate would not be fast enough to catch somebody walking through a beam. Try opening and closing a contact on your system, in say 1 second, and see if it is montored. If somebody is walking at average pace how long will they be in the beam for?

                  Comment


                    #10
                    You probably could connect the motion detector to a 555 timer chip and have have the timer chip hold the motion detection circuit in the active state for sufficient length of time for the scanning action to scan through and detect it. After the chip times out, the it would go back to the non active state.
                    Why I like my 2005 rio yellow Honda S2000 with the top down, and more!

                    Comment


                      #11
                      Agreed but that would not cover the case of the beam being broken for a time less then set on the 555.
                      HOw about counting the number of times the beam is broken (cmos decade counter), and then reading that value into the system and resetting the counter. That opens up a new field as you could use 2 beams and determine which way the "flow of people" was.
                      Coming from a time when we had to design and build using TTL and CMOS I tend, initially, to think of using hardware to solve some of the problems, especially timing ones.

                      Comment


                        #12
                        A 4017 chip probably could be used to make a simple counter (limited to 10(?) events). The program could check the chip outputs via something like the data in pins on the parallel port and see how many had occurred since the last check/reset cycle. As far as determining how many people are in a room, I would use a $40 K-Mart B/W IR cam with mic to count them myself real time and see and hear what is currently going on. A lot more direct than infering from beam break counting.
                        Why I like my 2005 rio yellow Honda S2000 with the top down, and more!

                        Comment

                        Working...
                        X