If you’re a small, poor team, these wouldn’t help you do better in any appreciable way. A 4 CIM kitbot is still going to be the move for most teams, because, unless you’re already consistently performing on field, throwing money at a new product wont help.
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Yup.
For what it’s worth, the hole pattern on the back of the bell matches Rev’s standard hole pattern for pulleys, so this is supported out of the box.
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I’m going to add to and amend my earlier post.
First, I am going to try to get some of these for my team. The finances require that we cut back on other stuff, but these will probably work well with the CTRE libraries that my programmers already love, and that makes these the best option available. If we want to be competitive (and we really do), then I don’t see how we can not try to get some in the drive base.
Second, I’ve been comparing this new motor revolution to the earlier COTS revolution, especially the frame materials, including the VersaFrame and the AM14U. When COTS happened what made me happiest was that the floor of FRC was rapidly rising. Simpler methods of making a quality robot that was robust enough to make it through at least one full event plus practice time. There was some financial investment, yes, but teams that had always struggled were going to be able to make better robots, faster, and easier. This feels really different. The floor hasn’t shifted up; instead, new products are going to help add 5% to the top performing teams. Teams that can’t make the most of these new motors will scrap together the funds and find it didn’t help them much, if any (is that my team? I hope not, but maybe). Teams that can’t find the $ or who aren’t the first in line when pre-purchasing happens will just work with what they have, and find the elites at events getting further ahead.
I’m a teacher, and the “achievement gap” has been a thing as long as I’ve been aware. How do we help the low performing students grow by huge amounts and help them catch up with their top-performing peers? How do we do this without hindering the growth of students already having so many advantages? It is a conundrum and a constant frustration. I know FRC isn’t public education. I know. But I still really, really want students and teams that struggle with lack of resources to find FIRST to be fun and engaging and worth their time and the dollars they can come up with for entry fees. I worry that this new round of improvements are going to make that harder to do.
Thanks for letting me rant. I do appreciate CTRE, and Vex, and AndyMark, and Rev, and all the rest. Y’all make this stuff happen as much as anyone, and I thank you for what you’ve done to make FRC such a great experience. I hope that my worries about this are unfounded and prove to be wrong.
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We don’t have to design for low load when using 775pros.
Mechanisms can get real lightweight/floppy/sketchy/simple when the motor has torque margin to just turn anyway, no matter what kind of nonsense is happening downstream of it.
Why not? That function is 100% within the TalonSRX library, it should work on a programming level. Might not be super optimized, but you should be able to just set appropriate current limits for each & then go.
The mechanical power should be additive when the controls are active (accel/deccel), the coast settings probably don’t match and might make weird things happen.
I agree with your point that this will probably mostly help the top performing teams, but as pointed out in the Motor price comparison thread, the price difference between a 4 motor drivetrain with Falcons vs. NEOs is just $100. And it’s only $68 difference with an equivalent CIM drive. I think people are seeing the $140 each as a bigger difference than it actually is once you account for motor controllers.
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It’s naive to suggest a low resource team buys new motors every year.
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That’s true. But when it does come time to upgrade/replace, the price difference is not as great as it initially seems.
I think the biggest difference is that any team receiving the kitbot will essentially already be purchasing a 4CIM drivetrain. Conversely, the $450PDV voucher you get for opting out of the kitbot isn’t enough even to afford 4 Falcon 500s.
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So how many Falcons will be in the KoP?
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No, it’s not. They interface presented by the Falcon 500 may be the same interface presented by the TalonSRX. It may accept the same 1’s and 0’s from the Rio on the CAN bus, so it may be that the host-side (i.e. the software on the Rio) is the same. But, the SRX is a brushed motor controller and the FX is a brushless motor controller. Under the hood --in the motor controller–the software HAS to be different.
Let’s say, for example, that the Master/Slave relationship on the bus is currently set by CAN command from the master to the slave that basically say “Ok. Set your voltage to 3.5 volts” “Now set it to 4.5 volts” “Now go to 8.4 volts” etc… What does the FX do? It’s not telling the Falcon motor “go to 3.5 volts,” because that’s not how brushless motors work.
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I’m newer to the team I’m on, but in the 6 years they’ve been around it doesn’t look like they ever bought new CIMs. They just keep shredding last year’s bot (or KOP). I do know they bought one redline before.
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This is a big question given the confirmed cost accounting rules for 2020
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Does anyone know if Vex will be releasing 32 DP motor pinions for the splined Falcon shafts?
Teams can use motors and motor controllers for many years and only replace them on an as-needed basis. We have CIMs in our inventory labeled as “2006” that are still in fine shape and could be used. I think there are many low resource teams that will accumulate the “free” CIMs they get in the KOP each year and keep using them over and over and then use their resources to invest in other items that are more valuable to improving their performance than buying these motors.
I expect that some low resource teams will benefit from this new product introduction because high resource teams will donate their CIMs, miniCIMs and motor controllers to those low resource teams as the high resource teams adopt these new motors.
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That’s essentially how PWM works, and the Talon FX supports PWM.
In fact, I wouldn’t be surprised if the Talon FX is designed around receiving percent output/voltage commands in general, both from CAN calls and from the output of its internal loops, then internally translates that to what the brushless motor needs. That seems like the simplest way to do it from CTRE’s perspective.
I recall seeing an earlier post in which Nick Lawrence said that Andymark will offer 15T 32DP Falcon spline bore pinions.
I do not think this is right. I am on a reasonably competitive team. We ended up with only drivetrain encoders (which we ended up not using). We also have a pile of sparks, talons, and victors from various years from KOP, FIRST Choice… Same with Cims/Mini Cims/775 pros. We have sunk costs that are not accounted for. Thus a new set of 6 falcons of these costs 850 for us, whereas cims cost us nothing. This is the issue for lower resource teams. We can not spend $1000 annually on a new motor and controllers.
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Sweet, the MK2 module uses that pinion as well. Falcons are overkill for steering swerve, but that would clean up so many wires…
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