My team is considering buying new mk4 SDS swerve modules for this season (we’ll be testing them in this off-season) but we can’t decide between neo’s or falcons for the module, we generally have more experience with Neos as we have mostly used them for the past 3 years and have rarely used falcons. We’re concerned how easily the falcons may break as we don’t have a very big budget and can not afford to be burning through falcons when testing swerve, Neo’s are much cheaper however they have noticeably less power and torque, so what I’m wondering is the loss of power not that bad and we can go with neos and be fine? or should we go all-in with falcons instead and just accept we have to pay up if they break?
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“Much less” might be an overstatement…
I know many teams who went with NEOs for their swerve modules and had no problems. IMHO you’ll be just fine.
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NEOs have about 2% more torque per amp if the gear ratios for Falcons and NEOs are adjusted to match the free speeds. Functionally they are not very different even though the Falcon has a higher peak power. The bigger difference is in the non-latching encoder and CAN cables on a NEO, compared to the soldered CAN within the Falcon, making the Falcon more reliable on a robot.
If you feel like you’re having spotty performance with NEOs and can trust members to repair Falcons once they arrive, go Falcon. If you are happy with NEOs and have had few or zero failures, stick with NEOs.
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I would vote “Falcon” on this because of the number of wires and objects per swerve drive. There’s a LOT of stuff associated with making NEOs run and you have to package that close to the drive. Makes swapping the whole drive a challenge and ties up more real estate.
One place the NEO ecosystem shines is a swerve running a NEO550 for steer; that packages smaller than a full NEO
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While you’re unlikely to fry either (assuming you’ve fixed all the problems with the Falcon), with a constrained budget and purchasing ability the split controller on the NEO becomes more attractive as well. I’d be more than happy to deal with a few more wires if it means I can actually afford to have enough spares.
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Falcon problem were scary this year. We had one lock up on a swerve module when the screws loosened up (they were taken apart and loctited.) We are also considering switching to NEOs.
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Reasons for Falcon 500 (from a CTRE stan):
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Until Rev releases a “CAN-IN-A-BOX” solution, can utilization / crowding is not fun to deal with, and a CANivore (compatible with falcon 500s) is a very quick solution to can bus utilization problems
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Characterizing (sys-id) your drivetrain with falcons is a little easier to deal with due to measurement delay issues with NEOs
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integrated controllers on the falcon help save space
I’m fairly sure Rev is brainstorming/providing solutions to some of these issues soon.
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As @IndySam mentioned, that does not appear to be the experience of teams this year.
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Our team ran the MK4i Modules with Neos. Had no issues and would use this setup again.
The encoder wires hurt us on a couple mechanisms, but not on our Drivetrain this season. Looking into some solutions to make this more reliable.
I don’t see the extra cost as worth it for the falcon’s personally. Its easy enough to make a clean Neo Swerve solution in my opinion, if you take your time and think through it.
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One other question is gear ratio, does anyone have experience with the L2 or L3 modules? We were originally considering L2 but after talking to cheesy poofs at Houston we learned they were using L3 which made us consider using those instead, what we worry about is how much pushing power we would lose by going with L3, especially if we used neos
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We used L2. They were fine. I think the L3 are a bit Niche, and not great on a full-weight robot. 254 doesn’t do a whole lot of “stopping” like a lot of teams would do (ya know…to shoot and stuff), so it’s possible they saw differently.
Now its possible to order different ratios if you really want to optimize things, but I’d say that the L2 is a safer bet. Especially since you don’t know what the 2023 game is yet.
The encoder resolution is also be a factor when doing odometry or velocity control. Falcons have a 2048 CPR encoder vs 42 CPR on the NEOs. There is also a 112ms filtering delay in the NEOs which makes good control difficult (this is customizable on Falcons). Both motors might be fine when considering a specific team’s requirements, but just something to keep in mind.
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ah okay thanks, cool mount design btw
since you guys used the inverted I also kinda want to know, how hard at all was it to fix the module? We wanted to use the inverted as well but we worry about the accessibility of the module in case it breaks
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166 ran Neo swerve this year and it was perfectly fine. We had a CAN bus issue early in the season that was fixed by wrapping the connectors with electrical tape so they wouldn’t separate from each other
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Well. It never broke, so I don’t have a whole lot of experience fixing it. Obviously care should be taken in assembling it (use loctite, follow instructions, etc.) but this module seems pretty much indestructible if you grease the gears.
We had a spare, but it would have been a little tricky to change out had it broken, probably slightly harder than the MK4. The MK4i being made of 7075 Aluminum was a huge selling point for us though, especially with the climbing challenge this year. We decided a module less likely to break was a better bet than one that was easier to replace.
Something I’d like to look at in the off season is a replacement free spinning omniwheel that could be sub-ed in a MK4/MK4i Module. That way if something ever did go wrong, and we had a quick match turn around, we could still play.
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I think the best solution to the integrated/separate controller issue. Is controller hats that lock onto the motor or you can have a non controller hat with the leads to the controller. As long as the lock on is tight.
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This. Would. Be. Amazing.
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Was there an explanation given as to why they ran L3 that made it an obviously better choice than L2? Like they determined that running L3 was more efficient than L2, or allowed them to make faster cycle times because of X, Y, Z? Or are you saying that because this well performing team said they’re running L3, now you should obviously consider it too?
If it’s the last one there (you’re only considering L3 because a successful team ran that ratio), I’d argue you’re choosing what ratio to run for the completely wrong reason(s). Work to determine desired gear ratios using more quantitative means. What will yield you the best cycle times theoretically, what is controllable for your driver, are you traction limited or not, how much current is your drivetrain (or mechanism) going to draw both on average and peak, etc.?
*some teams
As much as I want to like NEOs, I have seen more reports of problems with NEO+Spark Max than I have with Falcons, even with Falcons being broken out of the box. The unpluggable cables with the NEOs are an inherent failure point that Falcons simply do not have.
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Literally every Falcon shipped this year had to be torn apart by customers to fix factory defects.
It’s not just 2022: I personally helped two teams overhaul their gearboxes in 2020 because their Falcon set screws worked their way into the rotor and destroyed everything. I don’t think there’s good evidence to support your claim that Falcons are more reliable.
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