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-   -   New Speed Controller Announced (http://www.chiefdelphi.com/forums/showthread.php?t=68714)

Richard McClellan 07-08-2008 14:40

Re: New Speed Controller Announced
 
Quote:

Originally Posted by MikeDubreuil (Post 760659)
This is a great video. Things I noticed:
  • It would be nice if the Brake/Coast feature was a switch and not a jumper. (People lose jumpers)

  • The advantage of making it a jumper is so that you can connect it to one of your digital output ports and control it on the fly. Sometimes teams will use brake mode in autonomous and coast in user control, if that is what the drivers prefer.
    Quote:

  • CAN looks very powerful. I love how you can daisy chain Jaguars together. This will keep wiring simple.
  • I agree, this will be very slick. Unfortunately it won't be available the first year.
    Quote:

  • The Jaguars run on 12V (from the literature). Can you assume they know the robots electrical system will be 12V in 2009 with some sort of 24V transformer for the cRio?
They are aware of all the features of the new control system, and since all the motors are going to be 12V (I guess I can't say that with certainty, actually) it would make sense for the speed controllers to have 12V input.

Greg Needel 07-08-2008 14:48

Re: New Speed Controller Announced
 
I wonder if teams will be able to use the CAN network even if it isn't supported. All you would need is to buy the CAN module for the rio and hook them up, unless they are hardware disabled this year. I wonder who the first team to do this will be. My money is on 111, or 330.

Jon236 07-08-2008 14:50

Re: New Speed Controller Announced
 
Here's a good demo of the Jaguar. While it's clear from this that we won't use the CAN in 2009, no mention is given of the sensor support (Hall and encoders) mentioned in the press release.

http://www.youtube.com/watch?v=2ikgguMKqBk

Richard McClellan 07-08-2008 14:55

Re: New Speed Controller Announced
 
Quote:

Originally Posted by Greg Needel (Post 760668)
I wonder if teams will be able to use the CAN network even if it isn't supported. All you would need is to buy the CAN module for the rio and hook them up, unless they are hardware disabled this year. I wonder who the first team to do this will be. My money is on 111, or 330.

I asked about this at NI Week yesterday and they said that the FPGA image will not support the CAN module, and since you aren't legally allowed to change the image for 2009, so I guess you could do it, but it wouldn't be worth the effort since you'd have to get rid of it for competition anyways.

Lowfategg 07-08-2008 15:02

Re: New Speed Controller Announced
 
Quote:

Originally Posted by Richard McClellan (Post 760672)
I asked about this at NI Week yesterday and they said that the FPGA image will not support the CAN module, and since you aren't legally allowed to change the image for 2009, so I guess you could do it, but it wouldn't be worth the effort since you'd have to get rid of it for competition anyways.

I still can't think of a good reason for disabling it. If we can't use CAN then all these really end up being is really large Victors.

Also, since I am new to FRC, I am guessing it would be illegal to strip off the silly plastic case on these. Might help weight and size (as well as cooling!).

Richard McClellan 07-08-2008 15:08

Re: New Speed Controller Announced
 
Quote:

Originally Posted by Lowfategg (Post 760674)
I still can't think of a good reason for disabling it. If we can't use CAN then all these really end up being is really large Victors.

The only reason for disabling it is to reduce complexity since getting the new system is a huge change on its own. They wanted to finalize the FPGA image early to allow ample time for testing, and didn't have time to include support for CAN.

So, yes, they are really large Victors, but there's still four advantages that will apply for 2009 -
1. lower cost than the victors
2. better protection from metal shavings getting inside
3. higher frequency output to eliminate the "whine" that all FIRST robots with Victors have, usually most noticable at low speed.
4. built-in limit switch control to stop motor from going one direction or another

Quote:

Originally Posted by Lowfategg (Post 760674)
Also, since I am new to FRC, I am guessing it would be illegal to strip off the silly plastic case on these. Might help weight and size (as well as cooling!).

Yes it probably will be illegal to do that. I agree it would help weight and size because the PCB inside is at least 1/4", maybe 3/8" smaller than the plastic housing on all sides. That would add up to a lot of space savings. But it really isn't worth the risk of getting metal shavings in because there's no protection.

I do know they did extensive thermal testing to make sure the fan and ventilation was adequate and ran the controller well above its designed limits, and didn't fry anything. It is designed to automatically shut off if it reaches 60A or above for more than 2 seconds. It takes a second or two to cool down, and then will turn back on.

AdamHeard 07-08-2008 15:13

Re: New Speed Controller Announced
 
Quote:

Originally Posted by Richard McClellan (Post 760677)
So, yes, they are really large Victors, but there's still four advantages that will apply for 2009 -
1. lower cost than the victors
2. better protection from metal shavings getting inside
3. higher frequency output to eliminate the "whine" that all FIRST robots with Victors have, usually most noticable at low speed.
4. built-in limit switch control to stop motor from going one direction or another

Eh, even with that, my team will be using victors in place of these for 2009 (as far as it is allowed). I can already see the size and weight savings being beneficial.

Richard McClellan 07-08-2008 15:21

Re: New Speed Controller Announced
 
Quote:

Originally Posted by AdamHeard (Post 760680)
Eh, even with that, my team will be using victors in place of these for 2009 (as far as it is allowed). I can already see the size and weight savings being beneficial.

That seems logical, assuming you already have a supply of Victors lying around. For the teams that don't have a supply, it would be more difficult because the KOP will come with Jaguars, not Victors. They haven't said how many, but I would guess 4 since that's the usually number of motor controllers included. So that's an extra $460 for 4 Victors.

Greg Needel 07-08-2008 15:40

Re: New Speed Controller Announced
 
Quote:

Originally Posted by Richard McClellan (Post 760684)
That seems logical, assuming you already have a supply of Victors lying around. For the teams that don't have a supply, it would be more difficult because the KOP will come with Jaguars, not Victors. They haven't said how many, but I would guess 4 since that's the usually number of motor controllers included. So that's an extra $460 for 4 Victors.

I am going to wait for kickoff to make this decision to see if they are actually in the kit also how much they are each. With a ton of untested hardware this year it may be worth the extra money for victors just to know you have something that is bulletproof.

I think I must reiterate what Dave said, that FIRST hasn't said anything about these yet. While I am sure that there is some relationship don't get to excited or bent out of shape till you see them in your tote. Considering that they are hyping these things up without having the production cases on them yet doesn't instill much confidence.

Joe Ross 07-08-2008 16:42

Re: New Speed Controller Announced
 
Quote:

Originally Posted by Jon236 (Post 760670)
Here's a good demo of the Jaguar. While it's clear from this that we won't use the CAN in 2009, no mention is given of the sensor support (Hall and encoders) mentioned in the press release.

http://www.youtube.com/watch?v=2ikgguMKqBk

It wouldn't make sense to have the sensor inputs active, without a way to do anything with them (ie send them over the CAN bus).

Quote:

Originally Posted by Dave Flowerday (Post 760630)
Another thought: with the increase in functionality offered in the new controllers I hope they're getting a very serious and thorough testing. Adding that much complexity and software to something that's as safety-critical as a speed controller definitely increases the risks of bugs. Having a bug in something that's supposed to turn OFF the motor when the robot is disabled would be scary... I think a lot of people have taken for granted that with IFI, when you disable the robot with a disable switch it is OFF. Personally, I'm not going near a robot w/ the new control system unless it is physically powered-off until I gain enough confidence that it works the way it's supposed to. As a software guy I know all too well that trusting software for my safety can be a dicey proposition.

If done correctly, moving the limit switch handling to the speed controller will increase safety, as that functionality is small, easy to test, and (hopefully) unable to be overridden. I would be much more scared if all of this was built into the core operating software.

I can't name all the times we've had a software logic error which rendered limit switches or another safety device ineffective.

MikeDubreuil 07-08-2008 20:18

Re: New Speed Controller Announced
 
Quote:

Originally Posted by Richard McClellan (Post 760672)
I asked about this at NI Week yesterday and they said that the FPGA image will not support the CAN module,

They better have a free upgrade service for the new software. I don't want devices in the KOP that require me to purchase something (in this case at least an emulator) to upgrade their functionality.

MikeDubreuil 07-08-2008 20:26

Re: New Speed Controller Announced
 
Quote:

Originally Posted by Joe Ross (Post 760705)
I can't name all the times we've had a software logic error which rendered limit switches or another safety device ineffective.

That's Dave's point... what process is in place to qualify the software? Will the software pass a safety board?
With IFI's system and the Victor I feel comfortable putting my finger in a pinch point if the system is in the disabled state. I will not for a couple years with the Jaguars.
... the million dollar question for me is why Luminary Micro would like to step into the motor control business? What do they have to gain given their current product line? I don't understand.

Billfred 07-08-2008 20:32

Re: New Speed Controller Announced
 
Quote:

Originally Posted by ajlapp, emphasis mine (Post 760534)
-full current sensing and feedback for position control, when they unlock the feature in '010

Perhaps someone can find this out: If we go wild on speed controllers for 2009, will we be able to enable these features in 2010 when it's the night before ship day and we need just that one extra speed controller?

EricVanWyk 08-08-2008 00:17

Re: New Speed Controller Announced
 
Quote:

Originally Posted by MikeDubreuil (Post 760732)
... the million dollar question for me is why Luminary Micro would like to step into the motor control business? What do they have to gain given their current product line? I don't understand.

Luminary is not getting into the motor control business. They are in the motion control controller business. The Jaguar is essentially a reference design that shows professional EEs how easy it is to create a strong motor control algorithm using their processors.

I'm an electrical engineer, which means I have sales reps and vendors trying to sell me on their product lines all the time. Usually this involves them bringing in food in exchange for an hour of our listening time. Invariably, they bring in demo boards - power points just don't cut mustard. I'll bet you lunch that their sales reps will be have these in their demo boxes by February.

I doubt very much they are doing this for the money. They are doing this for the same reasons NI is:
1) They get the FIRST message.
2) They get targeted effective advertising to their core market.
3) They know they'd be stupid not to.

Richard McClellan 08-08-2008 07:46

Re: New Speed Controller Announced
 
Quote:

Originally Posted by Billfred (Post 760733)
Perhaps someone can find this out: If we go wild on speed controllers for 2009, will we be able to enable these features in 2010 when it's the night before ship day and we need just that one extra speed controller?

I'm not exactly sure I understand the question, are you asking about availability of the Jaguars? As far as I know the current plan is to distribute them via Digikey, for any controllers needed on top of what's included in the kit


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