FRC Blogged: - Motor Controllers

[PayneTrain]

I'm so happy right now I could cry.

[AdamHeard]

Originally Posted by JesseK

The real solution would be for teams to stop designing mechanisms that consistently hit the 40A + mark for extended periods -- which means more teams need to do the math.

It's not possible to guarantee your drivetrain will never, ever in an FRC match draw current that would possibly reset the jaguars.

Due to a shortage in speed controllers, we redid the drive on a practice bot with jags and they tripped all the time. This was the same drivetrain that ran flawlessly all season (2011) in regards to speed controllers.

[jason701802]

Originally Posted by JesseK

The real solution would be for teams to stop designing mechanisms that consistently hit the 40A + mark for extended periods -- which means more teams need to do the math.

Why? All the hardware we're using can handle the current.

[dyanoshak]

Originally Posted by andreboos

I'm somewhat worried about this change from a control perspective - last year there were reports of Jaguars losing their state when they lost power, so any CAN configuration commands (PID, voltage ramping, e.g.) had to be re-sent. This will become much more common if overcurrent results in tripping breakers and resetting Jaguars rather than just disabled motors.

I would argue that you won't see much of a difference. The breakers take WAY longer to trip and that is only when they heat up due to prolonged excessive current. If you're consistently tripping the breakers, I'd say you have bigger problems to worry about than a resetting Jag.

As always, keeping the battery fully charged will minimize the chance of a Jaguar browning out at ~6V. I'm confident that teams using the advanced CAN features also know to check for the "I just powered on" flag so they can reconfigure the reset Jag.

-David

[Akash Rastogi]

Originally Posted by Joe Ross

I assume you are talking about 1718? They are testing the Talon, but not as part of the FIRST sanctioned beta test. The FIRST Beta test hardware has not been announced.

Yes I was, thanks for the clarification.

[Nemo]

Having a choice between Victors and Jaguars will be fantastic.

I hope all the Victor 884's we bought last year will still be legal.

[andreboos]

Originally Posted by dyanoshak

I would argue that you won't see much of a difference. The breakers take WAY longer to trip and that is only when they heat up due to prolonged excessive current. If you're consistently tripping the breakers, I'd say you have bigger problems to worry about than a resetting Jag.

As always, keeping the battery fully charged will minimize the chance of a Jaguar browning out at ~6V. I'm confident that teams using the advanced CAN features also know to check for the "I just powered on" flag so they can reconfigure the reset Jag.

-David

That won't be a problem for veteran teams, but I think there will be a good number of teams who try CAN for the first time without considering a Jaguar reset. To be honest, if I had not heard of that issue, I wouldn't have thought of it either last year when I experimented with CAN.

Ideally, a team would manage their own current limiting with CAN, but for many teams, a stall will certainly trip breakers. (although if they trip them while accelerating normally, that is definitely a design problem)

[AdamHeard]

Originally Posted by Nemo

Having a choice between Victors and Jaguars will be fantastic.

I hope all the Victor 884's we bought last year will still be legal.

I really, really can't imagine they'd make them illegal. It would be a huge blow to teams financially without a solid reason of doing so.

[Racer26]

Interesting news, this. I assume Jaguar's and Victor 888's are different animals?

Perhaps IFI used some of the knowledge gained in purchasing the rights to Jaguars to improve the 884's into the 888's.

Would still be nice to have a straight answer from HQ what combination of Victor 883/884/888, Jaguar (Black/Grey), and Talon will be allowed.

The safe assumption is 884's and Black/Grey Jags, but I have a feeling Talon's and 888's will be allowed too, and possibly 884's dropped from the allowed list.

[Jared Russell]

Originally Posted by Nemo

Having a choice between Victors and Jaguars will be fantastic.

I hope all the Victor 884's we bought last year will still be legal.

The blog entry mentions that IFI will be donating Victors to all rookie kits, and will be giving all teams vouchers to be used on their choice of Jaguars or Victors.

Sounds to me like they will be legal...

[wilsonmw04]

So, does this lay to rest the perception that there was bad blood between IFI and FIRST after the FTC split?

Lord, I hope so!

These two groups working together is a powerful thing.

[Brandon Holley]

Awesome news. Way to step up IFI.

-Brando

[AdamHeard]

Originally Posted by Jared341

The blog entry mentions that IFI will be donating Victors to all rookie kits, and will be giving all teams vouchers to be used on their choice of Jaguars or Victors.

Sounds to me like they will be legal...

His question was probably referring to the fact that IFI has announced the Victor 888.

[jhersh]

Originally Posted by 1075guy

Perhaps IFI used some of the knowledge gained in purchasing the rights to Jaguars to improve the 884's into the 888's.

Where on earth did you come up with this? Did you actually read Frank's blog post?

[Jon Stratis]

Originally Posted by Jared341

The blog entry mentions that IFI will be donating Victors to all rookie kits, and will be giving all teams vouchers to be used on their choice of Jaguars or Victors.

Sounds to me like they will be legal...

The question is what victors will be donated? They have several to choose from - 883, 884, 885, and the new 888. I'm guessing the 883 and 885 won't be considered (they're more expensive and run at 24V), but from what I understand the 888 is essentially a remade 884 with a linearized output.