View Single Post
  #15   Spotlight this post!  
Unread 26-09-2012, 10:01
Mike Copioli's Avatar
Mike Copioli Mike Copioli is offline
You make it pretty We make it dance
no team (Retired(3539, 217))
Team Role: Engineer
 
Join Date: Jan 2006
Rookie Year: 2001
Location: Romeo
Posts: 453
Mike Copioli has a reputation beyond reputeMike Copioli has a reputation beyond reputeMike Copioli has a reputation beyond reputeMike Copioli has a reputation beyond reputeMike Copioli has a reputation beyond reputeMike Copioli has a reputation beyond reputeMike Copioli has a reputation beyond reputeMike Copioli has a reputation beyond reputeMike Copioli has a reputation beyond reputeMike Copioli has a reputation beyond reputeMike Copioli has a reputation beyond repute
Re: Victor 888: Upgrade to the Victor 884

[quote=Gdeaver;1187367]The window motor thermal shut down with the locking pins removed and a jag was only seen when used in a positioning application controlled by a PID. We used the window motors for our swerve steering - 4 wheel independent continuous rotation. With the jag we had intermittent thermal shut down with the jag. We switched to victors and had no more problems even with extended run times during practices in a hot building in the summer. We have used the window motors in other non - positional applications and not had problems with the jags. Of course if the window motor is over loaded it will shut down with any controller. It will live to run again. For what ever the reason jags and window motor in positional applications is probably not a good idea. We have used the banesbot motor and transmission for 2011 and 2012 avoiding this problem.

Quote:
Originally Posted by Gdeaver View Post
Did you find that the output of the Talon was linear or did you have correct it in software?
The output duty cycle is scaled linearly to the input, no additional math was needed to obtain a linear output.

Quote:
Originally Posted by Gdeaver View Post
There have been many versions of the jag. I'm almost certain one version used lock anti phase. If I remember right they have gone from a high side switcher to locked anti phase to the current low side switching. ?
The FRC version of the Jaguar has always been a high side switching synchronous sign-magnitude switcher. If there are any plots to prove otherwise I would like to see them.



Quote:
Originally Posted by Gdeaver View Post
The manual states the pulse as .9 to 2 ms is this a typo? Should it be 1 to 2 ms and will use the victor motor routines for programming?.?
This is not a typo. The Victor routines will work with the Talon. It is always a good idea to calibrate any motor controller however.

Quote:
Originally Posted by Gdeaver View Post
If we end up using Talons they will have fans.
Another motor controller option. I like options.?
This is probably a good idea if you are performing back to back practices at your build facility. However in a competition it may not be necessary. If you notice the Talons thermal plots are on a 10 minute interval with a 30% duty cycle (3 minutes at specified current, 7 minutes off). This is on purpose as most matches have ~10 minute turn around. (start to start) Now keep in mind the matches only last 2 minutes and 15 seconds. So even if your robot slams into a wall at full speed at the beginning of auton and continues to run at full speed for the remainder of the match, you will not damage the Talon. With that said it can only help with performance to use the fan. Our rule of thumb is use the fan for any Talon on a 40 amp breaker. Of course this is only relevant if the Talon is deemed legal.
__________________
Mike Copioli
CTRE Hardware Engineer
http://www.ctr-electronics.com

Team 3539 The Byting Bull Dogs
2013 Michigan State Champions
Team 217 The Thunder Chickens
2006 World Champions
2008 World Champions
2009 Michigan State Champions
Reply With Quote