Last weekend, my team, 5776A, participated in the VEX Sacramento State Championship, which we’d been looking forward to ever since we qualified in November. Honestly, after over 3 months of meeting every day working on driver practice, tuning our programming skills/autons, and scrimmaging with local teams, we felt like we were ready to compete at our best and beat our previous skills score of 43.
Sadly we found that this wasn’t the case. Our robot uses 3 line sensors, two to detect ball movement, and one to detect our robots puncher position, all of which are used extensively in not only our autonomous programs but are CRUCIAL during the driver control period as well. In essence, line sensors work by emitting a faint infrared light and detecting how much is reflected back. Our brand new line sensors read values of around 2900 without a ball covering them, and 100-300 when the balls passed over them, giving me (programmer) the ability to detect a dip in the values and tell the robot that it was carrying a ball. In addition, many other teams relied on a vision sensor for their autonomous/programming skills programs, which the direct sunlight affected as it caused the sensors to overexpose.
Unfortunately, the event was set up in a way so that the fields were placed 5-6 feet from a massive glass wall that allowed sunlight to pass through unobstructed. The problem with this is that the fields were completely bathed in direct sunlight + infrared, meaning that our line sensors were consistently reading values of only 100-200, instead of the 2900-3000ish that we were used to. This absolutely destroyed our tolerances, and calibrating didn’t help because the sensor was barely reading above its minimum value to begin with. I and our other programmers scrambled to fix the issues, which we managed to minimize by making our robot fully manual, but that caused an extreme drop in speed and consistency. We lost the perfect ball auto-indexing program and macros we had spent so long on that gave our robot a competitive advantage. So yes, this affected us, but I want to stress that we’re not just complaining about our own problems; From my gathering over 20% of teams competing were affected by the sunlight in some way and the performance of their robots was degraded.
That’s alright. What angered us was the lack of responsibility taken by the EP of the event and our Regional Support Manager. Not only did our EP refuse to close the curtains to the window wall (which were motorized), but she also pushed the blame onto our teams. I quote, “All of these other teams(not using sensors) are doing fine, why can’t you?”. She even said, “We knew it was a possibility (that sensors could be affected) but decided it would be okay.” Our Regional Support Manager was unable to be found at that time and calling his “event day phone” yielded no response even after I left a voicemail detailing the problem. I and others affected persisted and practically begged our EP to run skills on the practice field instead (which was farther away from the glass wall), to which she threatened “Talk to me one more time and I’ll disqualify all of your teams from judged awards”. She did say later on that she didn’t have permission from the venue to close the curtains, but completely refused to take any effort to remedy the situation and also refused to give us the venue’s contact for us to ask permission.
Now you might think "This just seems like the kind of rant a team would make after mispreparing for a state competition and not qualifying".
Let me preface this next part by saying that yes, 5776A did qualify to the World Championships a couple of days after our State Championship through a skills score we received at the Google Signature Event (unqualified skills spots). We waited until after we received our invite and registered to post about our situation. This post isn’t meant to read like a rant, and we understand that unforeseen issues can arise the morning of the tournament. We’re not at all asking for teams to be given world qualification spots now. This is more of an issue about responsibility, or lack thereof. I’d feel absolutely crushed if I was one of the teams that paid $250 and drove 3 hours to an event just to see their world qualification chances destroyed by an improperly managed event and no one taking responsibility for it.
We’ve got a few questions we’d like help answering now in order to move on with the situation.
What can teams like mine do when faced with similar situations?
What kind of standards can we expect from a State Championship in the future?
Can teams expect to be provided a proper lighting environment at the World Championships or should we avoid using light-based sensors at all?
Whose responsibility is it to deal with issues like these when they inevitably pop up in the future? Is it RECF for picking the venue? The EP for improper planning? VEX for making sensors susceptible to ambient lighting changes? The students for using these sensors?
Thanks for making it through the post. We appreciate every response.
- Sid P on behalf of: