I would like to build a robot which follows a virtual path (Not a visible path like a 'black line on a white surface', etc).
I'm just enthusiastic by seeing some sci-fi videos which show robots carry goods and materials in a crowded place. And they really don't follow a physical line. They sense obstacles, depth, etc.
I would like to build one such robot which follows a specific (virtual) path from point A to B.
I have tried a couple of things:
Using a magnetic "Hall effect" sensor on the robot and wire carrying current (beneath the table). The problem here was that the vicinity of the hall effect sensor is so small (< 2cms) that it is very difficult to judge whether robot is on the line or off the line. Even using series of magnets couldn't solve this issue, as my table is 1 inch thick. So this idea flopped :P
Using an ultraviolet paint (on a line) and using UV leds on the robot as sensors. This will give more Zig-Zag motion for the robot. And due to potential threats of using UV light source, even this idea flopped :P
I finally thought of having a camera on top and using image processing algorithms to see whether robot is on the line or diverging.
Is there any better solution than this? Really looking for some creative and simple solutions. :)