Video surveillance, when the car is off

**debugger** · 03-28-2006, 02:39 AM

Does anyone have any ideas on how to implement video surveillance when the car is off.

Lets say we have a fully functioning CarPC with capture card, cameras and sofware installed. Also, wireless card might be used to transfer data to home or office. (ad-hoc)

Any ideas how to power the unit?

2nd Battery + a switch or some capacitors?
dual boot with linux just for video capture?

But, I'm interested more in how to wire everything....

Are there any intellingent power supplies that would work ? ACPI..

**Bugbyte** · 03-28-2006, 02:55 AM

The computer will run your battery dead in a matter of hours. A laptop might stretch for awhile but if you leave it overnight, your battery will be drained.

Search on this topic using terms "video surveillance" or variations of that theme. It's been discussed fairly often.

**Specimen** · 03-28-2006, 03:48 AM

I greed with bugbyte, battery would die to quickly. But you know what, that might be a good theft deterrent. Then they can't drive away in your car cause the battery would be dead

**RC51Rob** · 03-28-2006, 03:54 AM

I have also thought about this and am still debating on one of two things.

1. Have the computer go into standby when key is off and come out of hibernation at scheduled intervals (how often depends on battery power) and wirelessly send couple of pics to home pc.

2. Have the computer come out of standby when dome light goes on and start sending video feed until car gets out of range (or I get there with my .45)

I'm sure there are plenty of other ideas out there too

**Specimen** · 03-28-2006, 03:58 AM

On a serious note, you might do something where you connect a relay somehow to your car alarm so that if it goes off, it will turn on your computer. From there you can have have something connected to a serial line or have some hardware device send some key command so at bootup, your computer knows its in a theft state and it will start recording, grab GPS data, and send an e-mail to you with pictures/movies or the person stealing your car with the cars exact gps location. Or send a txt to your phone. I thought about this but the time the computer boots and starts recording it might be too late. I was thinking of doing something like that but have a 2nd computer, maybe a nano board monitor everything. that was something I wanted to do when I first started my project years ago but haven't figures a clean way to do it yet.

**sama** · 03-28-2006, 04:35 AM

I'm trying to do exactly this. I've got an M2-ATX (160W) and power hungry system, so this will be a challange. Surveilance is a failry intensive task so system load will be high when monitoring.

So far, the safest option I can think of is this:

add a second battery with an isolator. I'd like to use a massive truck battery of some kind. I'm not sure if I can do this without upgrading my alternator or if an isolator configuration would be enough. and always have one of those emergency start batteries just in case. I think that's a good idea generally to have it when a carputer is in the car, even if the PSU is an intelligent one... u never know when it might spaz out.

on the software side, since nothing needs to be done graphically, code can be written to monitor and record without blitting the graphics across the bus, which would save a ton of bandwidth = computation = power consumption. And also by reducing the nubmer of writes using motion detection should minimise hd power consumption. These last measuers can't work wonders, but they would certainly help.

**debugger** · 03-29-2006, 01:05 AM

Originally Posted by Specimen

On a serious note, you might do something where you connect a relay somehow to your car alarm so that if it goes off, it will turn on your computer. From there you can have have something connected to a serial line or have some hardware device send some key command so at bootup, your computer knows its in a theft state and it will start recording, grab GPS data, and send an e-mail to you with pictures/movies or the person stealing your car with the cars exact gps location. Or send a txt to your phone. I thought about this but the time the computer boots and starts recording it might be too late. I was thinking of doing something like that but have a 2nd computer, maybe a nano board monitor everything. that was something I wanted to do when I first started my project years ago but haven't figures a clean way to do it yet.

Thats a great idea! I will post my setup as soon as its done. I'll use a proximity sensor (if someone aproaches the car within few feet) to turn on the power for the computer along with continious motion detection ( to know when to record)

**Specimen** · 03-29-2006, 02:21 PM

that will work even better, since the computer will start to boot before they even get into the car. The problem with that is it will turn on your computer, but if it keeps switching on/off for the motion or proximity your computer will shut off and turn on a alot. Just something to think about.

**Vinister** · 03-29-2006, 02:49 PM

as far as battery life that's easily remedied. I just did this to an old aircooled westfalia van. (the battery, not the pc heh)

I got a deep-cycle marine battery, pretty big, but should do 15 amps for 12 hours. In my opinion that would be enough to keep the pc running and recording a camera. I used a $10 150amp constant duty solenoid. I hooked it up using 4g to the alternator. I used the charge-indicator wire (little blue wire) from the alternator to trigger the relay. That way, the 2nd battery can be drained completely dead, the vehicle will still start on the main battery, and once the alternator starts charging (after you give it a rev), the 2nd battery is connected and re-charge begins. voila.

Another thought is a motion sensor. Go to a car stereo store and buy a dual-stage radar sensor (about $50). It will have 4 wires: power, ground, 1st trigger, and 2nd trigger. One of the zones is meant for 'inside' and the other for 'outside'. Hook it up to your alarm, but only connect the 'inside' trigger to your alarms door pin input (using a diode), and connect the 'outside' trigger to a relay. the trigger is negative so connect power to the other side of the relay, and connect it to the trigger of your power supply. Use standby on your pc, which you can do easily with the battery setup mentioned above, and your pc will resume almost instantly when the outside zone is activated.

All you have to do is start your cam monitoring software before you park. Anytime someone comes near your vehicle, the computer will boot up and recording will resume. Set windows to run for 30 minutes then go back into standby or something.

**Bugbyte** · 03-29-2006, 08:56 PM

Seems to me the easiset solution would be for the computer to ask for a security code when it boots. If it doesn't get a code in a few seconds, start recording, send the GPS location, etc. etc.

Use the second battery to allow the computer to be in suspend mode so restart is nearly instantaneous.