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IR curtain

Hello all, I am designing an IR curtain with TX array on one side and RX array on another side. TX side controller and RX side controller are different not same. I am using timer on both side for synchronization but i am not getting results. I want to synchronize transmitter and receiver without any GPIO line. I want to synchronize it with IR -Tx and Rx sensor.
If any one has idea how to synchronise it please help me.

Regards,
Sagar

Parents
  • Hello Per Westermark, First thanks Per Westermark for your valuable feedback. From IR curtain i want to detect shape of moving object.If i will not synchronize Rx and Tx side controller i will lose the exact shape of moving object. I tried to synchronize both sides of controller through timer but i failed. Then i tried to synchronise both controller from out put of first IR sensor but i failed when object is in front of first IR sensor. As i want the shape of moving object it is necessary to synchronise both controller.

    Tried to synchronise from first sensor:
    Rx side:

    { 1. check all sensors output 2. wait for first IR sensor to be detect-> again go to 1
    }

Reply
  • Hello Per Westermark, First thanks Per Westermark for your valuable feedback. From IR curtain i want to detect shape of moving object.If i will not synchronize Rx and Tx side controller i will lose the exact shape of moving object. I tried to synchronize both sides of controller through timer but i failed. Then i tried to synchronise both controller from out put of first IR sensor but i failed when object is in front of first IR sensor. As i want the shape of moving object it is necessary to synchronise both controller.

    Tried to synchronise from first sensor:
    Rx side:

    { 1. check all sensors output 2. wait for first IR sensor to be detect-> again go to 1
    }

Children
  • Still little information.

    I'm not sure why you need to know what the sender does - does the sender somehow modulate the beams?

    Because else I would expect the sender to just be a number of beams transmitting continuously, and the receiver detects at what times the individual beams gets blocked or reaquired. This can work quite well to detect a two-dimensional shape if the object moves at a known speed. Having additional beams besides the main curtain helps to detect the speed as long as the object is not changing shape - a human swinging their arms is harder to handle.

    Or are you trying to save on electronics by flashing the individual beams in a sequence and have maybe a mirror or similar and end up with a single detection signal - so the receiver needs to know which of the individual beams that is currently detected? An alternative to that is if you can modulate the beams so there are a high-frequency component that specifies beam ID while the low-frequency component is "object blocking beam" or "object not blocking beam".

  • Hi Per Westermark,

    I am using an 8051 controller,and with one controller i am handling 9 receiver on Rx side and there are 9 controllers serially with there 9 receivers on it.

    On Tx side also i am using 8051 with 9 transmitter and 9 controller serially with there 9 transmitter on 1 controller. I am trying to save on electronics by flashing the individual beams in a sequence. On Tx side i am making 1st ir transmitter ON then make it off, then move to next ir transmitter and so on. After 9 successive ir transmitter i am sending ack signal to another controller to start its transmission in a sequence. On Tx side i am modulating beam so on receiver will come to know which Ir transmitter is on.

    I am sensing ir modulated signal on reviver side. After one complete scan i am sending revived data from all 9 controller to PC for image formation.

    In above case i am not able to synchronise Tx side and Rx side.

    Regards,
    Sagar