They make all sorts of ultrasonic animal repellents that plug into wall sockets, so why not one that goes somewhere on your car? If they actually work, roadkill accidents in rural areas could drop significantly as deer/raccoons would simply want to stay away from the roads.

How would one go about building a simple circuit that's powered by the car? Also, what frequencies annoy animals but do nothing to people?

- Tom

http://www.sevendeals.com/p-3407-deer-whistle.aspx

http://www.sevendeals.com/p-3407-deer-whistle.aspx

Well, I'm going for the same result, but I feel that an electronic device would be much more effective. Also, the website states that the car must be traveling more than 35 MPH. I want something that turns on with the vehicle.

- Tom

Not sure if ultrasonic would be much more effective than any other sound. I've got emergency sirens that came with my police cruiser. I've used them to scare all sorts of animals off the road, but thats at daylight.

I think at night, the headlights shock them a bit. They are so surprised, I don't even think they hear the sound.

I think your safest bet against soon-to-be roadkill is a heavy duty metal bumper on a truck lifted so far up that the animals bones/antlers wont have as big of a chance at screwing up undercarriage components.

Either that or some flip down NVG's on your visor that don't cause the animals to panic, along with one of those star-trek phasers that instantly vaporizes it's target just in case they do panic.