can anyone lead me to a map exploration/path planning paper/algorithm/website for my problem:
We have 3 robots, which shall explore a 2D map, e.g. they drive over the ground while taking photos of it. The only obstacles on that map are the other 2 robots. The starting positions and the map is unknown; we use the TORO algorithm to refine positions via loop closing and also to merge the 3 local maps.
So we need an algorithm which controls the 3 robots so that every point is visited at least once, while creating the optimal path for every robot. ;) It must also be able to handle jumps in the coordinate system.
If your map would be known, then you could use some travelling salesman algorithm (with multiple couriers) but that would not work with an unknown graph. As the map is unknown, it is nearly impossible to get an algorithm that always produces optimal paths. You should look into some map exploration papers like this, this and this.