mikronauts wrote:You should consider using a Raspberry Pi 2 if you need more processor power
That's just it - at this point I have a Raspberry Pi B+. I bought it a few months before the Pi 2 was announced, so I don't regret buying it, and I haven't run out of processing power yet.
I expect to need more processing power when I learn how to use the camera and when I get serious about using speech reco for interacting with humans. I know a lot about speech reco (15 years in that biz), but I know nothing about image processing. Response time is critical in human computer interactions and the B+ is running far from real time reco in language model mode. I haven't tried limited grammars yet. Natural Language Understanding and "language" models are great for humans, but when the bot can only understand "shut up", "go sit in the corner", or "record a message for princess lea" (and then go find her and play it back), a limited grammar is all the bot needs.
When we close our eyes, we can't walk very straight, can't turn accurately, and jam our toes on the legs of the bed. My robot has a full skirt six-direction bumper for protecting itself, and I'm thinking there is so much I can do with the pointable IR range finder and the camera. The key is that my robot has all the time in the world to think.
I take pictures of birds. Many water birds stand motionless for long periods observing and thinking, then move from here to there five feet or so, and repeat. I know 512MB and 700MHz will not do everything at once, but coming from 30kB and 2MHz the Pi feels like I am adding a supercomputer to my bot.
One of the "simple life" concepts I want to try out: rather than use 9 axis, high demand processing while moving, I want to see if I can recognize the wall/ceiling joints with the camera and use the (approximately) known tilt/pan angles to determine what is the shape of the room, the bot's approximate position and orientation in the room. (This will take me a year to program and if it takes the bot ten minutes to run the program while sitting idle, the bot will be keeping "busy" and conserving energy by not running around much. I really don't want the commotion of a bot running around. I decided not to add a bot to an iRobot vac for that reason.
If I end up killing my B+ accidentally, I'll replace it with a Pi 2, but the B+ is going in the bot for the foreseeable future.