Thursday, August 28, 2008

What do the PolyGnomes do?

Last year's robot after its win at a scrimmage (this was not the final design)

As the chosen 'leader' of our team I thought it might be helpful to explain what we're doing as part of our robotics team.

The PolyGnomes participate in the First Tech Challenge, a competition that involves building a robot for a special game that changes every year. The games are announced in September, and the teams all scurry to build for the first competitions in fall and winter.

Last year's game had 4 teams per match. Two alliances, one red, one blue, of two teams each, compete against each other to score ring-shaped scoring objects either on flat, hexagonal, movable goals, on posts attached to these goals, or on square areas of the playing field. Depending on the scoring method, various amounts points are awarded (more for the posts, and less for the floor goals).

The first 20 seconds of each match consisted of an autonomous, code-controlled mode where the team could not communicate or control the robot with a radio controller. Some teams could not write code for this, and their robot would stay in one place during that time.

After the autonomous mode, the 2-minute-long radio-controlled mode begins (allowing autonomous functions as well if the programmers wish). Using large clunky RC controllers, each team would attempt to score as many rings as possible until the match ended.

Take a look at this video for a better description:

Once the points were tallied up, the alliance that won would get one Ranking point. The interesting part, though, is the teams in that alliance would also get Qualifying points, a measure of how many points the opposing team had. In other words, the closer the game, the better the rank in the competition.

We were lucky to do very in our competitions, considering the fact that it was our first year.

However, for this year's game we're going to be able to use more advanced tools, since the FTC (First Tech Challenge) is switching to the Mindstorm kit from the Vex kit. As the sole coder for last year (I'm getting some help this year), I'm very excited about being able to use a compass, color sensor, accelerometer, and tons of other tools for our kit.

In addition, I have many ideas for organizing our team. For instance, our team journal (a mandatory log to have for the competition) last year did not cover many of the most vital changes we made to the robot, and it was not thorough (To no fault of the journal keeper!). If we can rotate jobs as notetakers and write the entries the week after we can avoid problems such as the notetaker leaving before the rest of the team does. Drafts of each entry would also help neaten the journal up, and drawings of each idea and prototype, along with photos pasted in would help make it something worth keeping. I am hoping to put at least some of our entries right here in the blog so that you, the readers, can participate in our process as well.

Our design process needs some work too. Time and time again, we would think of an idea, assume it would work, and then find that it does not work at all--after spending a week building it! My goal is to have all ideas worked out precisely on paper (or a 3d modeler) before touching the metal! Sure, a mini prototype is good, but only if the paper design really seems to work after it is drawn to scale.

Another thing I've found is once we make the fundamental design (such as an arm) it is hard to change to anything else. In order to have the best design, we should think of the best plan of action first, then think of the best design to fit that plan, and then, finally, begin work on building the prototype.

I think if we stick to these goals we will have time to design the best robot to conquer this year's game. Look forward to our first journal entries in september!

Wednesday, August 27, 2008


This blog is intended as a journal for the development of the Green Meadow PolyGnomes robotics team's robots. We participate in the FIRST Tech Challenge, and plan to document our design and building process for this year much better than last year. Expect interviews, weekly robotics journal posts, pictures, drawings and videos, as well as tips for other teams and helpful advice.

This blog may not get many posts quite yet, but expect it to begin really functioning this September, when the team gets together again to start designing the new robot.

Thanks for joining us in our exciting design process!