By Jim Kelly
Some thoughts on FLL bot design
Yesterday, I was able to closely observe 24 teams present their FLL robots to my team of 4 technical judges. During each team’s presentation, we were asking questions about their building and programming solutions as well as questioning them on their logical/tactical reasoning and teamwork as it applies to coming up with a robot to compete. During all of my observations and questioning, I kept a list of those things that I thought would be of interest to readers and/or other FLL competitors. These are in no particular order:
1. A noticeable lack of using sensors – I would estimate that 75% of the robots I saw did NOT use sensors, other than the built-in rotation sensor on NXT bots and encoding/rotation sensors on RCX bots. The Light sensor was the most frequently used with the Touch sensor coming in 2nd… what I found interesting was that most of the bots programs were pretty much 90% or more MOVE blocks and all movement was based on table positioning and lining up the robots (either using jigs or aiming visually).
2. Aiming – as mentioned earlier, most robots (probably 80% or more) were aimed using a visual point-and-aim method. Interestingly, when asked about the lack of consistency in test runs and competition runs, most teams admitted that their aim was off and very few indicated that using a jig was an option (or other fixed/sturdy object useful for placing the bot in the exact same spot every time).
3. Confusion over turning rates – many of the teams indicated that they switched to “rotation” movements instead of degrees because they couldn’t figure out why their robots would be programmed to turn 90 degrees but would typically only turn 40-50 degrees. This told me that there’s still not a good understanding (either by students or teachers/coaches) of how a wheel-circumference turn and a motor rotation are not 1:1. Most teams that answered this question about their design seemed to think that programming one wheel to turn 90 degrees in a forward direction and another wheel to turn 90 degrees in a reverse direction would result in the robot spinning in place 90 degrees and were surprised when this wasn’t the case- TEACHERS/COACHES PLEASE LISTEN: it is VERY important for students to learn to program using degrees. Using time isn’t a good option because it is so easily affected by battery power and rotational movement programming is okay, but it’s probably debatable if the accuracy is the same as with using degrees.
4. Teamwork – one of my questions that I liked to ask was this: “If I were to pick one of the team members at random and ask him/her to run the robot on every challenge, would that person be able to do so?” – I was basically trying to find out how many of the team members were cross-trained – many of the teams consisted of individuals who ONLY knew about the physical robot, some ONLY knew about the research portion, and others ONLY focused on the programming. While this is probably typical considering time constraints and interest amongst students, I cannot imagine that any team will benefit from not knowing a little of every aspect of the competition. It’s just my opinion, but I think that any student participating in the FLL challenge should have an opportunity to contribute to robot design, robot programming, and the research portion. We all tend to focus on our strengths, but coaches and teachers need to encourage those students who might tend to “blend into the background” and get them more involved.
5. Programming – I would sometimes encounter a team where only 1 or 2 was handling the programming. They typically would do all the talking and were very good at describing their work. But when asked if they had cross-trained their team and demonstrated the program in its entirety so the entire team understood the programs, most of them were at a loss for words. I asked one team where the SOLE programmer had all the information what would have happened if that member were sick or stuck in traffic and couldn’t make it? Keep in mind that we did NOT allow the coaches/teachers into the Technical presentation. Teachers/Coaches need to make certain that ALL the team members have at least a cursory knowledge of the programming environment – even better, having every team member trained on each program and able to EXPLAIN how each program works is even more impressive.
6. Tactical Planning – Only seen in a couple of teams, I was overly impressed by some teams that had done a sort of comparision on which challenges they wished to attempt compared to points awarded. Some teams were able to explain clearly their reasons for NOT attempting a challenge OR for leaving a challenge for last (typically, not enough points to go after since time was limited). Other teams were able to combine challenges in a way that I hadn’t seen before – when asked, they also were able to explain WHY they chose the path/route they did – very impressive. Some teams were SO FOCUSED on doing all the challenges and then couldn’t complete 25% of them successfully!!! One team in particular had worked on combing 3 of the hardest (IMO) challenges in one run and were able to nail it almost EVERY TIME!
I had a great time – met some GREAT teams and coaches and saw some extremely well-designed robots. I saw professionalism, sharing, courtesy, and respect exhibited. I hope all the teams had a great time. I’m hoping they’re seeing how working on a team can be fun. I also hope they see that math and science can be interesting and challenging and rewarding.
Lastly, I need to say hello to some teams that I met and spoke with – Nifty Muffins of Doom, Girls in Black, RoboChiefs, and Radioactive SPAM – I hope all of you had a GREAT TIME!
Jim