I've put a lot of thought to the whole robot 'thing'. My immediate instinct in reading about this is an art making robot. I can easily see why there's so much interest in 'what can a robot do FOR me?' (hauling things for you, cleaning up, fetching) but I'm more interested in 'what can a robot do WITH me?' Printers are great, but they're still just a static digital output of art. And they (primarily) print in ink on paper. That is a very tiny sliver of the art making world.
I spent some time searching for robots that make art and didn't really come up with much that seemed to take full advantage of what is possible. Hektor is great, but well beyond what most people are willing to even attempt (the documentation implies that it was months of full time work and even speaks to the complications of programing it) and only works in spray paint. There are various other 'snippets' of work made by robots around, but nothing that seems to be more than a proof of 'hey, I can program a robot'. There doesn't seem to be much interest in making a series of really beautiful finished artworks, but rather a collection of demonstrations from trade shows and videos of robots at work.
I'm very confident that I can program the iRobot to travel in some great looking paths. It appears to be more than capable of beautiful curves, spirograph like spinning and sharp corners. I'd really like to work a lot with setting the iRobot up to use lots of different mediums - more than just dragging a pencil or marker, or just spraying spray paint. There are many options for mediums, including:
pencil, marker, pen (as mentioned above)
paint with a brush
paint dripped or squeezed from a tube or syringe (similar to how the Fabber and other "3D printers" work)
charcoals and pastels
rolling paint (similar to how wall paint is applied)
Each of these would require a different method of attachment to the iRobot. Focusing on this would allow me to turn it into a very versatile piece of equipment where I would be able to program a path, choose a medium and go.
Another benefit to working with the iRobot over a printer is that it can run over a number of different surfaces in many sizes. Printers are primarily limited to paper that's less than a foot wide for home printers, and less than a couple feet wide for most commercial printers. A robot could apply medium to any size space (theoretically), and that surface could be paper, canvas, wood, metal, or anything else it could physically move over. This literally allows for infinite combinations, and allows for layering of different mediums/colors in ways a printer could never achieve.
I definitely intend to work on programing the robot start and stop applying mediums in addition to just dragging them, but I don't want to commit to doing with within the 2 month time frame. I definitely would NOT intend to stop work on the project just because the contest ends.
My end goal would be to modify an iRobot to:
hold and apply a variety of mediums (ideally in a quick-change way)
travel on a variety of carefully planned and adjusted paths, taking advantage of straight lines, curves and corners
and, potentially, program it to start and stop applying a medium
Here's an idea that I'm not really interested in working on that I wanted to share anyway:
Start with a vacuum style Roomba, attach some sort of cat attractant (feather, mouse, catnip, etc) to it, and set it up to run from the cat. That would allow the cat to get some fun exercise during the day (when there's likely no humans to entertain it) and it would help keep up with the cat fur vacuuming. I would probably buy something like that.