Engineering for Dummies..Not Really

While in high school, I was apart of the FIRST robotics team at my high school.  The funny thing though is that I am the worst at anything science or math related.  I did more of the business side, marketing, and etc, with some building, but no design or actual engineering.  However, during those years I was also a mentor of the 5th and 6th graders for the younger robotics program, FIRST Lego League.  This program used NXT robots that were to be programmed by the students to do certain tasks on a board with certain structures.  For example, they had to build and then program the robot so that it had an arm to pick up a lego truck and move it somewhere else on the board.  All tasks had to be done in certain constrained time period.  Coming into class and realizing that we would be using the NXT robots, I was rather excited because I had done this before.

I was sorely mistaken though, our robot was not going to turn out like the 6th grader’s one above, even though we are all in our 20s and they’re all 12.  It has been over 3 years since mentoring or doing anything engineering related, and I certainly forgot most of what I learned.  Reading the instructions and listening to what we have to do, I’m thinking “oh this will get done so fast”, but I was wrong.  The program, LabView had changed since the last time I had used it and had gotten far more complicated than I remember.

After figuring out where to find everything though, it got much much easier to use.  We finally put all the little lego pieces on and made car-type contraption, after dropping and losing them quite a few times.  First we just kept going it as fast as we could and seeing it lurch and had a good time with that.  Then we finally got to our actual assignment of having it go in a circle.  That was a difficult one because we were trying to figure it out before anyone told us what to do.  I can say that we had some trouble with it since we had no idea that to get it to go in a circle it needed to have two different speeds for the wheels.  After getting that figured out, we made one wheel a power of 75 and the other 25 by changing the specific ports on the program, we got it to go in a circle, only to have to go back to a different assignment of getting it to go straight.  This was what we were supposed to do the whole time apparently…

We got the robot to lurch quickly and slowly and had to measure the distance on the actual table and what the computer calculated it would be to find the percentage error.  We found the circumference of the wheel to be .172m, which we plugged into the computer while running the computer for one second.  This allowed for LabView to determine the distance, .174m.  We then ran it again and measured the distance on the actual table, which was .175m.  The figure out the percent error, we used the equation:

With our information, the equation was: .175m – .174m / (.349m/2)

.001m / .1745m  = .0057

This showed that the percent error for the distance was .57%, not that bad in my opinion because there will always be some sort of error when measuring by hand.