A friend of mind is trying to interest me in a project for him. He lives on an island in a lake, and uses a small electric boat to ferry himself and the family the 100 meters to and from the island. The problem is that they've only got one boat, and with family members constantly coming and going the boat is always in the wrong place. They've experimented with applying RC to the boat, but it's not been 100 successful.
I've worked with GPS's and compasses in the past and rekon I could easily design a project that could navigate the boat to within a few meters of the boathouse, the tricky bit would be get it to manage the last 10-20 meters. My current plan is a bright light above the door to the boathouse, and a 2nd light at the back of the boathouse. If the arduino can 'see' the two lights and one light is vertically above the other then it must be accurately lined up with the entrance, ifthe lower light is to the left of the upper light then the boat is too far to the left and needs to steer right, if the lower light is to the right of the upper light then the opposite applies.
This all relies on a sensor that can 'see' the two lights. I've never done any form of image processing, but I understand it takes a fair bit of processing power, possibly more than the arduino can provide.
Does any suitable sensor exist? is is there a better way of doing this project?
All suggestions welcome.