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Motion Detection cameras

Motion Detection cameras

Motion Detection cameras

(OP)
Hi all. I am new here so I will introduce myself a little before I address my problem.
I am a Computer Engineer (well almost.. about to have a degree). I am currently working in a Psychiatric Sleep lab as their systems expert.

We are in the midst of reforming an experiment. The basics of the experiment are to study sleep deprevation in pigeons. The way we sleep deprive them is by using a conveyer belt to move the bird a bit if it is beleived they are beginning to sleep.

Up till now we did this using SpyVision or something like that. But, I have been given access to 3 different cameras
Pixord 126n
Axis 2420
IQeye (cant remember the number)
all of which have an internal motion detection which can then send a relay signal out. Supposedly it can be DC but I have been having a problem getting it.
What I can get is about a .05mV AC difference on the Pixord.
I am in contact with Pixord to see if this is correct but here is what I would like help with if anyone can.

I know little about motors. I will need to use this signal to trigger some sort of motor to move the conveyer to wake the bird. What kind of trigger can I use? Or is there motors that come with small voltage triggers and have there own power supply.

Thank you in advance:)

RE: Motion Detection cameras

Hi brainteaser,

To answer in brief, you can:

1. Do a rectification of the AC signal and use a level detector to get a digital signal.

2. The level detector should be calibrated such that when the relay signal changes beyond a threshold (DC value corresponding to the 0.05mV AC), the level changes from say, low to high.

3. Use the level detector output to trigger a monoshot (monostable) circuit. Tune it sch that the monoshot output remains ON for a fixed period (t1 secs) where t1 is time for which the motor should run.

4. Use the monoshot output to switch a relay, that powers the motor. So, for the duration t1, your motor is going to move.

5. Remember that when you move the motor, your camera will detect motion again, and will give another relay signal for which you shouldn't switch on the motor - if that happens, the conveyor will move continuously! To solve this, you may cut off the 0.05mV relay output to the monoshot when you switch on the motor, and restore it when the motor stops.

[um.narayanan@gmail.com]

RE: Motion Detection cameras

Poor little birdies :)

The .05mV (or even .05V) does not seem right, more just like noise.

Could it be an open collector output transistor that you hook up an external load and power to? I would suggest contacting the manaufacturer as you stated.

Good luck (and don't let PETA find out)

Wheels within wheels / In a spiral array
A pattern so grand / And complex
Time after time / We lose sight of the way
Our causes can't see / Their effects.

RE: Motion Detection cameras

(OP)
Thanks for your help. I think the signal I was getting was just noise.
The problem was not feeding through my power properly on the right pins. Now that I can get a reasonable voltage I have to figure out what motor/conveyor/mounting setup to use/make.
Sure wish I payed more attention in Physics:S
Well atleast I got the programming/electrical part done:)

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