PIR sensor to activate a voice activated circuit

Discussion in 'The Projects Forum' started by 2electrified, Aug 3, 2015.

  1. 2electrified

    Thread Starter Member

    Sep 5, 2011
    30
    0
    Hello All,
    I am working on a project here and need some help. Here is what I am looking to do. Right now it currently stands at - a voice activated system is used to setup off traps. The person at the stand yells "Pull" into the speaker and the machine releases a target. The speaker is so sensitive, that even a clap sets off the machines. I thinking about using a PIR sensor. The PIR sensor would be set up so when the gun is raised in front of the PIR sensor, the PIR sensor turns "ON", which then put the speaker in ready mode, the shooter would then yell "Pull", the machine throws target. Then it would it repeat itself. The shooter would then go through the same follow through - raise the gun pass the PIR sensor, the sensor turns ON, which then activates the speaker, the shooter then yells "Pull" and so on. This would eliminate target being falsely thrown. The voice activated circuit uses LM324 chip. The PIR output is 3v. I am not sure if I need to go directly to the LM324 chip to tie in the PIR sensor to, or splice the PIR sensor to cable that runs from the speaker to the voice activated circuit. Would I a need a relay so when the PIR sensor is ON, the relay will close, put the speaker in ready mode and wait for the command then turn off until the sensor is triggered again. The voice activated circuit uses 15vdc as input power. The speaker is using the LM324 chip and uses 12vdc at pin 4 & pin 11. The PIR sensor uses 12vdc to power it, but outputs 3v at the out pin.

    Thank you in advance.
    Lisa
     
  2. ian field

    Distinguished Member

    Oct 27, 2012
    4,415
    784
    Might just be simpler to rig an IR break beam to trigger the target release as the gun is raised and cuts the beam.

    Save a fortune in cough drops too...........
     
  3. 2electrified

    Thread Starter Member

    Sep 5, 2011
    30
    0
    Thanks, but the IR beam wont work due to the fact that since there are left and right hand shooters, two sets of beams would have to be mounted on each station. Using the IR sensor I will have it mounted on a swivel arm which will move to the right or left. Thanks for your input. I was looking into the beam in the beginning but with the type of shooters wont work with this project.
     
  4. Reloadron

    Active Member

    Jan 15, 2015
    963
    232
    I first would reduce the audio gain of what you have. A system that reacts to ambient sounds obviously will not work well for this. You only want the audio portion to trigger on a sharp yell of "PULL".

    Next, using maybe a PIR to detect the shooter have the PIR enable or drive a One Shot where the one shot is used to enable the audio for only a short period. Shooter enters the box and gets to his/her ready and then they have 5 seconds, 10 seconds, whatever seconds to yell "pull" in a sharp well defined voice. Rather than a PIR even a simple foot switch could be used. The idea being the audio is only on for a short period waiting for the pull command.

    Personally I am not sure I would care for an automated system but whatever trips your trigger I guess. :)

    Anyway before adding a PIR I would try and get the existing system working as it should.

    Ron
     
    Last edited: Aug 3, 2015
  5. 2electrified

    Thread Starter Member

    Sep 5, 2011
    30
    0
    Hi Ron, thanks for your reply. The gun clubs are using an existing voice activated system. These units have been play for many years. They want me to tie into these units. I suggested the foot pedal in the way beginning, and they turned it down. They want the motion sensor option if possible. Lisa
     
  6. Reloadron

    Active Member

    Jan 15, 2015
    963
    232
    Well Lisa, this is why I shoot high power rifle and handgun, those trap & skeet shotgun people are just too finicky. :)

    Considering what you are up against and available options I would look to reduce the response of what you have and then look into a PIR sensor of sorts as I mentioned, using a one shot. You can't have the thrower responding (triggering) on random ambient noise and throwing birds. I would address that first.

    Ron
     
  7. 2electrified

    Thread Starter Member

    Sep 5, 2011
    30
    0
    Ron,
    The one shot you are talking about would that be the 555 timer along with the PIR sensor? I have made notes to address the other problems as well. I have to work on this at the same time. Thanks again.
     
  8. Reloadron

    Active Member

    Jan 15, 2015
    963
    232
    Yeah, with the scenario I have in mind the PIR (or any sensor you choose) would trigger a one shot and yes, a 555 would work fine. The one shot would enable the audio system. The audio syatem would only be enabled for the period the one shot is set for. So when the shooter is on the line nothing is going on and the audio trigger is disabled. Once triggered be it any form of sensor the shooter has X number of seconds to yell "Pull". Personally I like the idea of a foot switch to enable the one shot and subsequent audio trigger but it's their oyster I guess.

    Really none of this should be necessary if the current audio system were slightly desensitized. They likely have a microphone of some type driving an audio amplifier. You come off the audio amp through a diode like a 1N914 into a comparator chip. The comparator has a trip level which is likely preset and the comparator out likely triggers the solenoid in the bird thrower. That's a guess and conjecture on my part.

    Ron
     
  9. 2electrified

    Thread Starter Member

    Sep 5, 2011
    30
    0
    The current circuit, the microphones are using the LM324N chip (quad operational amplifier). Not sure what your knowledge level is working with sound activated circuits but do you think I can splice between the speaker and the wire that runs to the box to activate the lm324 chip or do I need to work directly with one of the pins on the LM324 chip itself. The box contains 5 individual chips so 5 speakers are connected to this one box. Thanks for your input so far. I really appreciate it.

    I agree about the foot switch. I think that would be easier to work with.
     
  10. ScottWang

    Moderator

    Aug 23, 2012
    4,855
    767
    The following circuit can be activated by sound.

    Mic → Amplifier → RC High frequency filter and isolation → Schmitt Waveform converter → Diode Cap rectifier → filp flop → Bjt → Relay.

    If you like then you can using logical level Vgs mosfet to replace the bjt and no needs to use relay.


    [​IMG]
     
  11. 2electrified

    Thread Starter Member

    Sep 5, 2011
    30
    0
    @Scott Wang - thanks for the circuit. Unfortunately, I have to use their existing voice activated system. I just need to figure out how to get the PIR sensor to activate the circuit so when the shooter is ready - he/she triggers the PIR sensor, yells "Pull" and the circuit does the rest, then resets itself for the next person. Right now when the circuit is active, any sound by the speaker triggers the traps out in the field. I do appreciate your input. Thank you.
     
  12. ScottWang

    Moderator

    Aug 23, 2012
    4,855
    767
    As what you said then you will need a AND gate to decide when the shooter is ready(on the right position) and that is active the high signal for one of AND gate, another signal is the sound "yell", when the yell sound occurs then the AND gate will get another high signal, so the output of AND gate will output a high signal, and then you can use this high signal to do what you want.

    The ready signal also can be a not ready signal when the shooter was left the position and then it will send a low or high signal, the signal as a reset signal, the issue is the signal of PIR, how is the signal of PIR when it reflecting from object, does the output is high or low or a low to high pulse, the same is when the reflecting object was left, does the output is high or low or a high to low pulse?
     
  13. 2electrified

    Thread Starter Member

    Sep 5, 2011
    30
    0
    @Scott - this is how I envision my idea to work. The PIR sensor is mounted at the station where the shooter stands. When the gunman raises his/her gun to their shooting position, their gun will trip the PIR Sensor which then would allow the microphone become active so then the shooter can yell "pull". The PIR sensor goes high when activated. The output voltage on the PIR is 3.3vdc when activated. The PIR sensor I have I can adjust how long it remains on before going low (0vdc)
     
  14. ScottWang

    Moderator

    Aug 23, 2012
    4,855
    767
    Could you draw the block diagrams for all the connections and label the voltage and signal.
     
  15. ian field

    Distinguished Member

    Oct 27, 2012
    4,415
    784
    Just how feeble do you think an IR beam is?! With a basic IR emitter/PD pair and some simple focusing lens, it would span the whole width of a shooting bay with no trouble.

    Using an IR laser - it could span the whole width of all the bays in the shooting range.
     
  16. 2electrified

    Thread Starter Member

    Sep 5, 2011
    30
    0
    thanks for your input Ian. The stands don't run straight in a line. The 5 stand forms a semi circle. Each station would still require a laser and emitter. Which means more cords and power for each station. The PIR sensor I can block out the dome cap that sits over the sensor to lessen any false triggers. Trying to keep it simple. If this doesn't work for some odd reason, then yes laser is a possibility, BUT I would still need to tap into the existing activated sound system. So no matter which option happens, the problem lies on how to tap into the current circuit so the board doesn't trigger any targets from any sound until the PIR sensor is triggered OR laser beam is tripped.
     
  17. 2electrified

    Thread Starter Member

    Sep 5, 2011
    30
    0
    @Scott, I will post a block diagram later this evening.
     
  18. 2electrified

    Thread Starter Member

    Sep 5, 2011
    30
    0
    here is my block diagram. PIR sensor project.png
     
  19. ScottWang

    Moderator

    Aug 23, 2012
    4,855
    767
    I was added some more details, you can check it, there is an AND gate used 1N4148 diode and resistor to replaced the normal IC gate, but this kinds of gates may not work well when the other resistance of device is too high.

    The transistor circuit was used to converting the output voltage of PIR from 3.3V to 12V.

    PIR sensor_2electrified_ScottWang.gif
     
  20. 2electrified

    Thread Starter Member

    Sep 5, 2011
    30
    0
    @Scott - I put a voltmeter across the red and black wires that run from the speaker to voice activated box and I am not getting any voltage reading. This is normal? Even when I talk into the speaker - the meter doesn't change. Thank for your schematic.
     
Loading...