An easier way to do this would be to grab a computer, install linux, connect webcam, install
Cheese, open terminal, type "cheese& while true; do xvkbd -text " "; sleep 300; done", and leave the computer always running.
Simply put, this would press the space button (shortcut key for Cheese) every 5 minutes (300 seconds). The images are stored in one of the image folders in linux. All you would have to do is make sure xvkbd is intalled too (basically its an onscreen keyboard for linux).
If you want to network it, you can try to grab a wireless webcam and see if that works. The above is just a very basic/simple solution that would give you kinda what you are looking for. Definitely not the best way to go about it, but it does work.