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Unread 12-03-2014, 17:30
NotInControl NotInControl is offline
Controls Engineer
AKA: Kevin
FRC #2168 (Aluminum Falcons)
Team Role: Engineer
 
Join Date: Oct 2011
Rookie Year: 2004
Location: Groton, CT
Posts: 261
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Re: Hot Goal Timing Issues

Quote:
Originally Posted by Tom Bottiglieri View Post
This weekend at the Central Valley Regional we noticed an issue with the synchronization of timing between the field management system enabling robots and the triggering of the hot goal lights and targets.

We found that robots were being enabled up to a second before the lights and vision targets indicating the hot goal turned on. This seemed to be a simple time shift as robots would stop moving before the lights turned off and the second hot goal lights would activate exactly 5 seconds after the first hot goal lights turned on. This creates 2 issues:

1) Given humans score the hot goal by way of the field lights and not the field timer, teams had approximately 6 seconds to score in the first hot goal and 4 seconds to score in the second hot goal.
2) Teams had to wait 1 second in auto mode to sense the hot goal. With multiple moving robots and shot being fired, the challenge becomes much different than initially expected.

Over the course of an entire match one second would probably not be a huge deal but given the 5 second scoring window for the hot goal, this bug equates to a 15-20% decrease in available scoring time. Many teams have designed their robot to score balls in the hot goal over a 5 second period. In some matches they are being given less than 4 seconds.

Here are some illustrated examples of this happening. These videos have a timer that starts in the first frame that I can see robot motion, which is the best indicator I have of robots being enabled. There could be more time of "enabled" on top of this as robots may not start moving at exactly t=0.

CVR Qualification Match 2: http://www.youtube.com/watch?v=mgI_PkgsuXA
In this match, the second hot goal is only active for 3.9 seconds. The first hot goal is not indicated until 1.1 seconds after robots are enabled. The second hot goal is activated at 6.1 seconds. Robots are disabled when the overlay timer shows 10.0 (you can see a ball in 254's robot start to move towards the shooter then fall as the single acting solenoid outputs are disabled.)

CVR Qualification Match 83: http://www.youtube.com/watch?v=RXKHpcc6ZOE
In this match, there is a .7 second delay from robots starting to move until the hot goals activate

CVR Qualification Match 11: http://www.youtube.com/watch?v=rycIqPJpbz4
In this match, there is a .6 second delay from robots starting to move until the hot goals activate

CVR Qualification Match 32: http://www.youtube.com/watch?v=9Q3KVlqbwvc
Since the robots are not visible in this video, I have synced the overlay timer to read 1.0 when the match timer on the field changes from 10 to 9. There seems to be about 1.2 seconds of delay from robots on to hot goal on, and a 3.8 second long second hot goal.

As an additional data point, we observed that the scorekeeper seemed to be enabling robots from the PC interface, not the blue hardware control box.

Of the issues listed above, it seems point 2 has a very simple fix. In 2008, drivers were not allowed to touch their controls once the “ball randomizer” had determined ball position and field crews could place them. The first hot goal could work in a similar fashion and be lit before the match starts.

Has anyone else seen issues like this? It would be nice to have these issues fixed for future events!


Thank you,
Team 254 Mentors and Students

We too have noticed hot goal timing issues at the Groton District event this passed weekend. It was such a problem that towards eliminations we dedicated our media student to filming the actuation of the hot targets so we could study them later.

There was a noticable 1 second delay between match start and goal actuation that was noticable with the naked eye. It was also appearant that one side was more affected then the other when looking at blue vs red.

Thank you for posting your videos they are very helpful. We too can post the videos we took at Groton if that will help the community.

What system are you using to detect hot targets? It also appeared that the last link "Qual Match 32" your alliance started with 4 balls in auto. How did the refs let you pull that off?

Regards,
Kevin
__________________
Controls Engineer, Team 2168 - The Aluminum Falcons
[2016 Season] - World Championship Controls Award, District Controls Award, 3rd BlueBanner
-World Championship- #45 seed in Quals, World Championship Innovation in Controls Award - Curie
-NE Championship- #26 seed in Quals, winner(195,125,2168)
[2015 Season] - NE Championship Controls Award, 2nd Blue Banner
-NE Championship- #26 seed in Quals, NE Championship Innovation in Controls Award
-MA District Event- #17 seed in Quals, Winner(2168,3718,3146)
[2014 Season] - NE Championship Controls Award & Semi-finalists, District Controls Award, Creativity Award, & Finalists
-NE Championship- #36 seed in Quals, SemiFinalist(228,2168,3525), NE Championship Innovation in Controls Award
-RI District Event- #7 seed in Quals, Finalist(1519,2168,5163), Innovation in Controls Award
-Groton District Event- #9 seed in Quals, QuarterFinalist(2168, 125, 5112), Creativity Award
[2013 Season] - WPI Regional Winner - 1st Blue Banner
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