A Petition for Better Regulations on PTC Checks at Worlds

VEX V5 Robotics Competition VRC
1

Dear @Karthik,
Whether we experienced it ourselves, or had been conversing with other teams that did so, we feel as though PTC checks at Worlds drastically affected the performance of some middle school, high school, and college robots that competed in eliminations this year. According to the PTC Authenticator page on the VEX Robotics site, “Based on extensive in-house testing and discussions with the PTC manufacturer, the PTCs in the motor will return to high levels (95%) of performance within 15-20 minutes of being tested. They will be “as good as new” within one hour after a test. Inspectors will do their best to keep this impact to a minimum and fair to all teams at an event”. Many robots were not given anywhere near the required amount of time prior to elimination matches for their motors to recover from their PTC check, and were rushed to the field after the check. In addition, when teams asked their head referee for time to let their motors recover, they were denied this necessity (see science division finals for an example). These checks forced some teams to use their one alliance time out to cool down and reset the motors, or face their motors stalling during the following matches, due to the lack of time for the PTCs to reset.

We would prefer that PTC checks do not affect the outcome of matches at Worlds in the future and would like to request regulations on these checks during Worlds. We understand that eliminations and Round Robin are on a tight schedule on the Saturday of Worlds. This said, we still believe that keeping a fair playing field is more important, as well as key in keeping with the spirit of VEX robotics. Seeing a team’s entire year of hard work, dedication, and extreme care all swept away because of a poorly timed motor check is truly heartbreaking. We would like either a regulation on the mandatory time given between a PTC check and start of that alliances next match, PTC checks to be conducted at a different time during that day, possibly after alliance selections or after team’s last match on Saturday, any other solutions VEX itself, as well as its competitors, would be able to come up with. Of course, we fully support PTC checking to verify the integrity of all teams competing, but we believe there are far better ways of implementing it. If there are any other suggestions on how to improve the PTC checking system, it would be greatly appreciated if those reading this would please put them on this thread. We hope this letter will encourage open discussion, between the both the VEX community and Karthik, or any other members of the REC Foundation, who would be willing to work together towards a solution to better the VEX Worlds Competition for all those involved.

Note: I (Lewie, team 8000) am not aware of any current regulations regarding PTC checks, but if they exist, I believe they were poorly enforced during Worlds this year, and would like to see the implementation of mandatory pauses before matches, and additionally a system to verify teams have at least 15 minutes to rest their motors before their next match and confirm with teams that ample time was given. Another suggestion (given by Brandon, formerly on team 20) was that PTC inspectors would put tamper evident tape or stickers over the inspected motors, to verify that the PTCs haven’t been modified over the course of worlds, being a similar system to the zip ties given out to put on the robot after inspections. Also this petition was created to hopefully bring this issue to VEX’s attention, not to criticize any particular referees or volunteers at VEX Worlds. We would like to thank every volunteer and staff member at VEX Worlds for giving their valuable time in order to allow the competition to run smoothly and make Worlds a great experience for everyone there.

Thank you for your time,
~ Lewie
Secretary of State, team 8000

This document was drafted and/or supported by:
Lewis (8000C), Fitch (8000A), Prabh (1104G), Akhil (5776T), Jaiveer (5327B), Kaushik (315G), Spencer (6135K), Justin (5074Z), Matthew (8000A), Andrew (8000A), Ryan (8000C), Nick (8000B), Wesley (5327W), Sam (60X), Tim (5327C), Eric (315X), Colin (former 1104M), Jeffrey (5327C), Michael (6210X), Cory (563), Theron (6135W), Keeley (2886), Andrew (315Z), Maxx (400X), Harold (400S), Charlie (400U), Sarang (5327D), Daniel (400R), Mona (315A), Nishant (315G), Andrew (5776), Josef (7700R), Bryon (former 86868), Nik (former 7581H), Matthias (2Y), Will (44576A), Cameron (62), Corey (mentor of 60X and 360), Abhinav (2D), Sharwin (5776E), AJ (7580A), Thomas (1104G), Gilbert (1404K), Ankush (285A), Brayden (4361T), Zach (5245A), Dane (2131), Dylon (86868), Nihal (1104V), Abhinav (former 1104 and mentor of 1104), Sam (333U), Jordan (6001C), Manitha (99000B), Joseph (6916C), Maryanne (9080H), Connor (1138B), Jess (21S), Jitesh (5776), Ethan (81Y), Mista (200), Shatayu (5776), James (2560E), Xinghao (2S), Arjan (1104S), Jasper (1492X), Nitai (1309A), Denise (2Y), Sidharth (former 5776,E,X), Zilong (7258A), X.Robo Team (33333, 55555, 66666, 42000, 23333, and 16666), Urmil (99000X), Ramanjot (99000B), Harrison (523H), Benson (600R), Chris (5689A), Nasir (4100A), Zilong (7258A), Luke (323Z), Drew (936B), Westin (6135K), Richard (200), Aiden (99000B), Prabh (99000B), Marrissa (former 6751C), Ben (6671), Sele (3922)

(Edit: added additional supporters to the list and link to poll)

2

My team had to play a match very soon after a motor was checked so we sprayed it with this coolant spray we had brought to worlds for the purpose: MG Chemicals Super Cold Spray. We have been very happy with this spray’s ability to cool down motors fast. This might be too expensive, but one idea is for the people doing PTC checks to provided teams with coolant spray.

3

Our observation was there simply isn’t any coordination between field staff and the PTC checker. Armed with a list of teams and PTC authentication rig they’re tasked with checking 24 robots at some time during eliminations, preferably early on.

When queried about the cool down time our alliance was told to check with the head referee. The show must go on and sometimes teams weren’t getting the allocated reset period. It appears no additional time was allocated during eliminations to accommodate PTC checks.

Perhaps the only thing missing is the PTC checker noting down the time testing was performed and the field staff verifying this before a match starts? Without any record of when testing was performed the field staff are in the dark. Maybe building in a countdown timer in TM for eliminations teams which automatically displays additional match timeout? PTC checks are now part of the game so why not integrate it properly.

4

They could just only check team immediately after a match. It would be easier than going pit to pit, and it would guarantee a cooldown period between matches.

5

That works for qualifying matches, but it gets a little more difficult for elimination matches. Everything happens so fast.

6

They checked ours at the queuing tables before finals, fortunately we brought air

7

I have a friend who said they stalled his motors right before semis and his drive stalled in the middle of a match, costing him his chance at finals.

8

They were checking teams at the queuing tables???!!!

9

Yes, they wouldn’t let them leave the queuing tables once you were there. Couldn’t return to pit.

10

Both 185A and 2131X were having burnout problems in technology finals because of PTC checks.

11

I observed the PTC checks at the queuing tables in the Arts division as well as other divisions. These tests were definitely match effecting. Testing them as they come off the field is a better idea and then DQ any teams that fail.

12

What if the PTC testers themselves had coolant spray on the days that there is competition? This will ensure that all teams have cooled motors before the match. Basically they would ask if the team would like to spray the tested motors (Tested motors only), and the testers would hand the team the spray to cool the specified tested motors to ensure fairness to the game.

13

The spray helps but even with the spray, the motors are still not at 100% right away. The problem is that the spray is applied to the outside of the motor and plastic does not transfer the heat away from the motor very well no matter how cool you make the plastic.

14

But you can get it pretty close with really good spray like the stuff I mentioned earlier. That stuff supposedly cools stuff to -50C. I don’t entirely believe that, but it still gets really cold. It has worked fine for my team. We sprayed a bunch on.

15

According to some people i have spoken to in vex cooling spray does very little to affect a motor unless it is sprayed inside of the gear casing. I have only have persinal experience with cooling only canned air.

17

I remember in skyrise when we were there we had the same issue and other teams that were in finals like 9090C and 5408F’s performance were greatly affected but the bad way of testing motors. Definitely they should reform the system.

18

Canned air isn’t as effective. There’s a difference between liquid coolant spay that shoots 6+ft and canned air that you have to hold upside down to make it do anything.

19

Last year at worlds, the two motors that they tested the PTCs on for inspection shredded their internal gears during matches (one on drive, one on flywheel). No proof that they were killed by the testing, but strange coincidence.

20

The way to test this would be to do a PTC test and measure the time it takes to trip the PTC. Then, spray the motors, and run the PTC test again and see if there is a shorter time.

21

That’s a very good idea. I have some of both so I might actually try that. After all, I have never actually tested my assertions. I am just assuming that since our drive didn’t stall in the match we had right after one of the motors was tested and since the liquid coolant spray is so much more impressively cold and powerful it works. That being said, we had a light robot.