Today was the third meet of this FTC season that we attended. We were considerably more ready for this one than previous meets because we finally have a means of getting balls up to the tubes. After I left last night, an engineer replaced the cardboard box ball hopper with one made of aluminum. Before things started, I changed the code a little to make the newly repositioned servo go to the right places when the buttons are pressed.
We passed software inspection easily, but the hardware inspection failed because one of our axles was too long, making the wheel stick out of the sizing cube. Our school's other team needed some help getting through software inspection (they didn't know how to get to the settings in the NXT), so I somehow ended up signing on the "Team Representative" lines for both teams. I wonder if the FTC people noticed.
I and the other driver for my team decided to switch driving roles - I thought somebody else would be better for the main movement controls given my less-than-stellar performances in the previous meets. In our first match, we started in the parking zone and ran the autonomous program that tries to use IR to find and kick the kickstand. It did not work, and just rammed into the side of the ramp.
(Side note: The FTC people chose to use the ramp we assembled in the competition field. I wonder if they noticed that it was held together entirely with tape. The rivets that appear to be holding it together are broken and don't connect anything. Evidently, the team mentor didn't tell them about the quality of our engineering.)
After the autonomous period in the first match ended, we did go over to the kickstand and knock it down. Unfortunately, a wheel gear slipped, and we were again rendered unable to turn. We pushed up the lift to test whether it worked, and it went up, but the servo cable was not long enough and therefore disconnected. The driver sort of managed to get us partially into the parking zone after I brought the lift back down, but I don't think it counted for points. Our alliance partner tried to put balls in tubes, but their controller stuck at an inopportune time and flipped them over. This match was a complete disaster and, of course, a loss.
In the second match, we started on the ramp and used the autonomous program that just goes down off of it. In tele-op, we knocked down the kickstand and collected another ball. When we tried to drop them in the tube, however, they completely missed - there were parts of our robot that pushed the tube away when we got close. We did push one tube up our ramp and almost got up ourselves. Our alliance member got several penalties - we also left one of the three tubes in the opposing parking zone - but did manage to park in our parking zone. This match was also a loss, probably thanks to all the penalties.
We had some time in between the second and third matches to adjust our ball intake and the code. They turned out to not help much, though. In that third match, we started on the ramp and debuted the completely untested program that is supposed to come down from the ramp and drop two balls in the 60cm tube. It got close, but the leaning of the lift made the balls miss the tube. Also, I forgot to add an instruction to stop the lift motor, so when it got to the top, it just kept pulling the string and started smoking. (This never happens in pure software!) In tele-op, the driver got a small ball stuck under our lower frame, which made moving really difficult. She did manage to shake it free, but by then there was only time to get one tube up the ramp. We actually tipped that tube over on the ramp, but it wasn't technically "tipped over" because it was at less than a 90 degree angle, so we got points for it. The opposing alliance got several penalties, so we won!
In the fourth match, we tried that ball-dropping autonomous program again, now with a stopping instruction! The lift didn't actually raise - my mistake had burned out the motor. (In pure software we would just restore from backup.) The edge of the ball hopper also clipped the floor near the bottom of the ramp, turning us off course. The robot autonomously T-boned an opposing bot quite intensely. Fortunately, there was no damage to either robot, and the first thing we did in tele-op was accidentally push a tube into the opposing parking zone. We tried to push the 30cm and 60cm tubes up the ramp, but had insufficient traction. Fortunately, our alliance partner was able to half-fill the 90cm tube and get enough points to win the match for us!
In the fifth and final match of the day, we went back to the simple down-off-ramp autonomous program. It had the same edge-in-ground turning problem as before, and left us with one wheel hanging and unable to move. Our alliance partner helpfully pushed us back onto the ground, but slipped our gear and knocked both the NXT and Samantha module off their mounts. We managed to park in the parking zone while our partner team filled the center goal. With that large amount of points, we won.
Three out of five isn't bad, especially considering all the mishaps that our robot experienced. The new driver said she now understands why driving is so hard. We really need to get the omniwheels on; with normal wheels, turning is slow and jerky but straight movement is fast.
We'll replace the lift motor next meeting.
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