Elise proximity alarm?

[ChrisB]

A question for those electronics engineers out there (ground loop, rob13572468): Would it be practical to make a proximity alarm out of the backup sensor systems in most new luxury cars. It just occurred to me that, to help alleviate the parallel parking problem, it might be possible (practical) to modify the backup sensor systems to work as a proximity alarm in a parked Elise.

My idea was to put a couple of those sensors in front and back, set them up to work when the car is parked and activate the cars horn when another car got within a foot, or so, of the Elise. The device could be turned on/off with a manual switch to preserve battery life if parked in a safe place. It should probably be inactivated when driving so when you're tailgating that pack of Hell's Angels, your horn doesn't start blasting away.

I'm not familiar with the electronics, or how deeply they might be buried in the donor car's computer system. Anyone think this might be a practical, cost-effective solution?

[ChrisH]

You would need to do some tests first to make sure how it responds to humans, not just objects. And, you would need to set the sensitivity (again, some experients), so that it is very short range. You also want to have it be sensitive to movement, not just an object close by, so that a car parked next to you doesn't set it off. And you want that movement to last for some period of time to let the person parking next to you have time to get out of their car and walk away. However, you do it, you are going to get a lot of false alarms unless your car is parked away from all other sources of movement.

[J-Son]

why not just take the needed electronics/parts off a junked car and set them up in the elise? they would then be already calibrated and ready to go....as long as the accident didnt harm those components.

[ChrisB]

Originally Posted by rucnok

why not just take the needed electronics/parts off a junked car and set them up in the elise? they would then be already calibrated and ready to go....as long as the accident didnt harm those components.

I believe they are only active on normal cars when the car is in reverse. With them active when the car is armed, it might set off the alarm whenever somebody walked by. Very embarrasing in the mall parking lot.

If they would only active the alarm when a very large object came near, they might work OK.

[scottyb]

You can allways buy aftermarket backup sensors off ebay. They are easy to wire. I installed them on the rear of my Elise to warn of small children and objects when I back up.

[SweetDaddyD]

Why go through all the trouble of re-inventing the wheel? Why not just buy an alarm with a Proximity sensor? I have a Viper (alarm) with one and it works fine, on another car. If you get around the cabin or lean in it says "Protected by security system, please stand back" in a pretty tough robot sounding voice. haha. It has a pretty sweet indiglo alarm flashing panel system indicator thingy too. (big blinking light)

[ChrisB]

Originally Posted by SweetDaddyD

Why go through all the trouble of re-inventing the wheel? Why not just buy an alarm with a Proximity sensor? I have a Viper (alarm) with one and it works fine, on another car. If you get around the cabin or lean in it says "Protected by security system, please stand back" in a pretty tough robot sounding voice. haha. It has a pretty sweet indiglo alarm flashing panel system indicator thingy too. (big blinking light)

The Elise already has a proximity alarm for the interior of the car. The thread started as brainstorming on some method of preventing some of the parallel parking, clam cracking incidents.

A good point though, maybe another Elise interior proximity sensor could be mounted in the front of the car. I think it has a sensitivity adjustment and the alarm unit is already set up to interface to it.