I adjusted the requirements and created Escape 2. This time the robot could not touch the walls of the box. Of course, they tried to wiggle out of this one by asking if the cords could touch. "Okay" I said looking at the cords sticking out of the back and thinking that would be fine. Then of course, one pair students takes all the cords out of the kit to wrap around the robot as a bumper. "No. That doesn't work."
Escape 2 turned out to be a fairly significant challenge. Several pairs of students were able to program the robot using the ultrasonic sensor to sense the long distance at the opening of the box and move their robot towards the exit. But more often than not their robots would catch a wheel on edge of the opening and get stuck. Another group decided to rebuild their robot in a minimalist fashion by changing out the big wheels and tires on the base robot for thin wheels and tires.
Ultimately, this group and one other out of 6 were able to complete the challenge. As the teacher, what to do? We have spent a lot of time already on this challenge and I felt it was time to move on. Some nagging questions remained. Do I allow all students time to complete challenges? Is it okay to move on with some having not done so? My initial thought is YES, this is okay to do. In today's world where many kids are so quick to shout "That's unfair!" when one kid gets something and they do not, this seems like an important lesson. People have different strengths. Many kids expect everything to be easy and doable, and if it is not, they give up. Certainly, if a student wants to take some time outside of class to pursue the challenge, I would gladly provide that time.
Any thoughts, ideas or advice on this topic would be much appreciated.
I'm actually up against a similar situation in my high school robotics, where we're using Tetrix bots to follow a tape line on the floor, find a tube standing on the line, grab the tube, and then leave the line to find a taped square on the floor and leave the tube inside the square. All autonomously!
ReplyDeleteWe've spent weeks on this challenge, and so far only three out of six girls are close (and two are a team using one bot). I'm giving them the rest of the week to work on it, then pulling the plug. It's happened like this many times in my 6+ years teaching robotics - you give a challenge and then realize it's way harder than you anticipated because of small mini-challenges embedded in it (like wheels catching on the edge of the box). In our case, the challenge of finding the square given that it's location isn't fixed relative to the tube (which can be anywhere along the tape line) is a tough one - coding a search behavior that reliably finds the square *and* knows where the bot is relative to the square's edge is difficult, though we've had some creative attempts.
Here's my solution: Whether or not the challenge was conquered by all, there was a ton of information gathered and a ton of learning that happened. There should be a post-mortem period in which students reflect, in writing, upon:
a) the elements they didn't anticipate about the challeng
b) how those elements affected their initial and final designs
c) how these surprises and design changes will affect their design process for the next challenge
Generally, my principle is "do, test, do, test", while the kids' process is "do, do, do, do, do, test". I'm trying to get them to challenge their assumptions and designs much more *along the way* so that the surprises are minimized and progress is more incremental and palpable. I'd be happy to discuss this more - obviously I have a lot to say!!
Thank you so much for your thorough response, Doug. I love your ideas.
ReplyDeleteThis is my first semester teaching robotics ever and I have some great ideas for next semester. Look forward to interacting with you more. Cheers, Bob