Strategy, Autonomous and Coding

I just wanted to make sure that this all gets documented somewhere. The flowcharts that Ed walked you through were awesome . . .

Remember that autonomous doesn’t mean that it’s ALL autonomous. Remember that you’re not just DUMPING your robot onto an unexplored uncharted terrain like Mars or something. Your FIELD has specific dimensions, and your INITIAL position can only be one of three choices. You as a HUMAN BEING will know a lot about your robot that you can tell it in advance with simple digital I/O switches and not have to build sensor systems for (i.e. you’ll know how many balls you have in your robot at the start, so why bother having it sense that information when you can input it directly as a binary value?). Hence the hard coded switches that will drive your if/then/else statements.

Also, you know a lot of about your enviroment and the game pieces. What does that mean? If you can get your robot into a certain, let’s say 4’ X 4’ area on the field by just plan feedforward (i.e. no sensor information), then you can use your auto-targeting system to do the FINE CALIBRATION work for aiming. On a fully charged 12V battery (a voltage supply that is hopefully regulated – I’m checking), you should be able to tell your robot to drive forward for 3 seconds, turn left, and drive forward for another 3 seconds for example to get to your ‘target area’. We’ll have to experiment with the turning.

Remember, your human drivers can do the COARSE POSITIONING, so use your complex sensors (i.e. vision) ONLY FOR FINE CALIBRATION. Figure out what the bounds of COARSE POSITIONING are BEFORE you start trying to get your feedback system to do EVERYTHING for you. The truth is, trained humans are far better than feedback systems (see Wired Article on a well practiced high school team that beat an MIT student team that had a bad-ass system but little practice): http://www.wired.com/wired/archive/13.04/robot.html

Use your surroundings to guide you as much as possible in SIMPLE WAYS. My graduate school research work was all about sensors and feedback systems that were computationally simple and cheap, and THUS much more robust right off the bat. You can do a LOT with touch sensors for example. Sophia had a GREAT suggestion about getting the robot to drive up to the RAMP and sense it with simple touch sensor and then aiming from there. That’s a GREAT idea.

Please analyze your PLAYING FIELD: Please don’t tell me you don’t know anything, because you do, with a little bit of work.

1. How high up is the center of the hoop?

2. What angle is the hoop set up at?

3. If you are 10’ away in front of the hoop and you can shoot the ball out at 10 ft/s, what is the angle range that you can shoot at and still get the ball in, provided that you haven’t reached the peak of your trajectory.

4. Answer question 3 if you are 9’ feet away.

An excel spread sheet would be a GREAT idea (since we don’t know what our initial velocity will be). Or as Shirin pointed out, you can probably even write code to do this. (Oh man, you are totally making me want to bust out Matlab . . .)

This is a great analysis problem ;) See you tomorrow! Yah, I might just skip the talk at Stanford on ‘Engineering Education’ since this is way too much fun.

- Emily