Thread: Jaguar Meltdown
View Single Post
  #45   Spotlight this post!  
Unread 04-04-2010, 16:55
boomergeek's Avatar
boomergeek boomergeek is offline
Registered User
AKA: Mr. D (Dick DiPasquale)
FRC #0241 (Pinkerton Robotics)
Team Role: Mentor
 
Join Date: Feb 2009
Rookie Year: 2009
Location: Derry, NH
Posts: 191
boomergeek has a brilliant futureboomergeek has a brilliant futureboomergeek has a brilliant futureboomergeek has a brilliant futureboomergeek has a brilliant futureboomergeek has a brilliant futureboomergeek has a brilliant futureboomergeek has a brilliant futureboomergeek has a brilliant futureboomergeek has a brilliant futureboomergeek has a brilliant future
Re: Jaguar Meltdown

Eugene,

Thanks for giving a more accurate description of the surge from the reversal of directions being better described as a current surge rather than a voltage spike. I believe our Jaguars had been set up for "brake" instead of coast option from the beginning of the season. (Before the two failures).
We have been using CAN control signaling.

I'm relatively new to FIRST (my second year). And I was kind of surprised that neither the speed controllers themselves nor the standard software for driving the speed controllers had sufficient defensive measures for preventing a full speed motors in one direction (with the momentum of a robot traveling 10 fps) being instantaneously subjected to full voltage in the reverse direction.

Overly sensitive joysticks can excite this problem ... as well as novice drivers that have no concept of electrical and mechanical stresses that occur when they forget the concept of the momentum for a 135 lb robot and instead try to reposition a robot as quickly they would an avatar on a video game.