CHDK as a car security device

ivanatora

6

« on: 18 / April / 2013, 09:54:17 »

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Hello,

I have a problem with my car - someone unlocks it and steal things from my trunk. It is happening several times before and 2 times I've got missing stuff. It is a 2001 Citroen C5 that is fairly computerized and I think the burglars have some hi-tech device to open it remotely.

I'm thinking of installing a P&S camera with a CHDK in the trunk and using a modification of the Motion detector script to shoot everyone that open the trunk. Has anyone done something like this?

These are the problems I can think of:
1) Power. The camera will have to be turned on for several days. Is there a camera that can last that long with the built-in battery?
2) Can CHDK script work if the camera is in sleep mode? If I manage to attach a bigger battery will the CHDK script work properly continuously for a long period of time?
3) Camera size. It have to be small, so it can be easily concealed. I don't want that camera missing like my other stuff

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waterwingz

12138

Re: CHDK as a car security device

« Reply #1 on: 18 / April / 2013, 10:01:26 »

Quote from: ivanatora on 18 / April / 2013, 09:54:17

1) Power. The camera will have to be turned on for several days. Is there a camera that can last that long with the built-in battery?

No. You might get a day of so but several days is not likely : http://chdk.setepontos.com/index.php?topic=9049.0

Quote

2) Can CHDK script work if the camera is in sleep mode? If I manage to attach a bigger battery will the CHDK script work properly continuously for a long period of time?

Yes. Not guaranteed but you should be able to get several weeks before the internal timers overflow /wrap,

Quote

3) Camera size. It have to be small, so it can be easily concealed. I don't want that camera missing like my other stuff

Probably your biggest challenge.

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Ported : A1200 SD940 G10 Powershot N G16

ivanatora

6

Re: CHDK as a car security device

« Reply #2 on: 18 / April / 2013, 10:15:49 »

Quote from: waterwingz on 18 / April / 2013, 10:01:26

No. You might get a day of so but several days is not likely : http://chdk.setepontos.com/index.php?topic=9049.0

Interesting. Is there any stats about power consumption of these cameras? If it is not too much, I might be able to hook it to the car battery.

I've got another idea - use the camera sleep mode and attach some Arduino-like hardware that will detect sudden light changes and fire the trigger. My Canon 50D is able to go at least month in sleep mode, so I think it is possible for a P&S camera?

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bill.sikes.7

11
sx130_1.01c

Re: CHDK as a car security device

« Reply #3 on: 18 / April / 2013, 10:16:48 »

I'm sure there is a simpler way, but I have an inverter that I used when I drove a truck. It would convert 12v to 110V and I would run my tv in my truck using it. It seems feasible that you could also hook up the wall adapter that you have for your camera to it and run your camera for several days with it. However, you would also run the risk of having your inverter stolen if it was not well concealed.
Another and probably more efficient way would be to built a small box with the resistors necessary to lower your car battery voltage to the voltage your camera needs. This way would certainly draw much less energy from your car battery. Even a rheostat would probably work if you set it using a multitester. There should be any number of ways to hook your camera up. And surely you will think of a way to conceal your camera. You have the advantage of knowing someone is trying to steal from you. They will probably be looking for the obvious item to steal and will not want to loiter around your car with the open trunk for too long.

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waterwingz

12138

Re: CHDK as a car security device

« Reply #4 on: 18 / April / 2013, 10:33:17 »

Quote from: ivanatora on 18 / April / 2013, 10:15:49

Interesting. Is there any stats about power consumption of these cameras? If it is not too much, I might be able to hook it to the car battery.

About 0.2 to 1.5 watts depending on what the camera is doing. If you use good switching regulator (many available from China for less that $10) you can assume at least 50% efficiency so less than 3 watts max. At 12 volts thats about .25 amps - it will take a long time to run down a car battery that way.

Quote

I've got another idea - use the camera sleep mode and attach some Arduino-like hardware that will detect sudden light changes and fire the trigger. My Canon 50D is able to go at least month in sleep mode, so I think it is possible for a P&S camera?

That would work too - sleep mode will run at about .2 watts.

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Ported : A1200 SD940 G10 Powershot N G16

waterwingz

12138

Re: CHDK as a car security device

« Reply #5 on: 18 / April / 2013, 10:34:55 »

Quote from: bill.sikes.7 on 18 / April / 2013, 10:16:48

Another and probably more efficient way would be to built a small box with the resistors necessary to lower your car battery voltage to the voltage your camera needs. This way would certainly draw much less energy from your car battery. Even a rheostat would probably work if you set it using a multitester.

Using resistors to try and match a required voltage drop is a bad idea with something like a camera as it has a considerable variation in current draw depending on what its doing.

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Ported : A1200 SD940 G10 Powershot N G16