Trailer Back Up targeting system

I've searched for something like this but couldn't find exactly what I'm looking to do, and am looking for suggestions.

Here's the concept - I am looking to create a sensor system for directing a vehicle backing up (a truck) to connect to a trailer hitch. Pretty simple.

I've looked at a couple ways to do this, ultrasonics to give me distances involved, but that's to the over all trailer. I'm looking to connect the ball on the truck - the hitch on the trailer more easily.

My general thought for display is either a set of LEDs that give me red/yellow/green visible from the tailgate or rear view mirror - or a dash mounted similar display with distance to the hitch. I looked at ultrasonics - which give me distance, and I could just mount 3 sets of those to the bumper - and calculate the difference between the 3 to triangulate.

But I also looked at targeting systems which use IR and or Lasers, with led on the trailer pulsing to similarly give me a targeting system to it.

Wondering if anyone has any suggestions or knows of a similar project? I'm really new to arduino but have a long background in hobby electronics so not afraid of much, just need to understand the best (better) solutions to problems like this.

Any help appreciated. Thanks in advance...

A pointing down camera just above the ball, so you can see it directly?

rjakobson:
Pretty simple.

It's not.

rjakobson:
Wondering if anyone has any suggestions or knows of a similar project?

Space shuttle docking systems.

Ultrasonics are unlikely to give the precision required for a hook up system.

Articulated lorries use a mechanical , large heavy bits of metal to achieve this. g

blimpyway:
A pointing down camera just above the ball, so you can see it directly?

Articulated lorry drivers do this regularly , without a camera.