NEO Brushless post testing opinion?

#21

AFAIK REV hasn’t released equivalent locked-rotor stall testing data for the NEOs. Personally, I doubt I’ll be using NEOs until I have that data on hand.

Based on antecdotes I’ve read on here, 30A continuous sounds like too much current to expect the motors to safely dissipate for a whole match.

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#22

Agreed. The only thing REV has said is that an 80A (output) current limit is safe. IIRC, that roughly corresponds to 20A input at 12V (but I could be way off - @Greg_Needel has also advised a 10A input limit ). Between 20A and 100A (unlimited stall current) there will be a sloping down line of “burns out in X seconds”, but sadly I don’t think there’s data yet to point out where that line runs.

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#23

~24:1 & 8:1

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#24

We just published some locked-rotor testing data here: NEO Brushless Motor - Locked-rotor Testing

Please take a minute to read through the information as the data is in a different format than what most are used to. In short, the data was taken at constant current limits instead of constant voltage limits.

Finally, the intent of the data is to show an approximate time-to-failure, not the current-torque relationship of the NEO. The time-to-failure depends on many different variables and the times you’ll see in the graphs linked above are not guaranteed.

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Neo motors pulling only 5 Amps when stalled?
#25

Thank you for sharing this testing! This will definitely help with designing mechanisms using NEOs

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#26

I can’t tell if it’s because I’m on mobile, but the images of the graphs are all fairly low resolution for me. I can’t read the keys clearly.

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#27

Would it be possible to add a spreadsheet of raw data to dive into?

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#28

If you tap and hold (or whatever gesture your phone has) you can download the image and zoom in.

@Owen_Busler I’ll work on getting raw data uploaded tomorrow.

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#29

you guys are awesome! thank you :slight_smile:

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#30

I was actually getting served low image photos (I was on Firefox for Android). Both view image and save image gave the same low resolution image. However, I’m getting high quality images on desktop. :man_shrugging:

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#31

Very thorough data. Thanks for releasing it.

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#32

Back to the OP - we tried these out on our elevator and 4-bar climber. They’re exactly what we were hoping for in both subsystems. We also swapped to 4-NEO drive and will see how that works this weekend. The embedded encoder and weight are the #1 & #2 reasons we like the NEO ecosystem (though cable management is a learning process). With that said, they probably won’t replace every motor we use.

The 775PRO / Redline will always be seen on our bot - they’re still great and less to manage for high-speed systems that do not need sensor feedback directly on a controller (intakes & belt systems). The BAG is still a super-easy-to-replace, lightweight, take-a-beating type of motor. It will still be seen on low/medium-load wrists via the SRX because the VersaPlanetary ecosystem is so great. MiniCIMs may be seen in certain “hold position” scenarios. CIMs are probably done-for.

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#33

Raw data can now be found at the bottom of the page: http://www.revrobotics.com/neo-brushless-motor-locked-rotor-testing/#raw-data

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#34

The only problem, besides a lot of issues at the start of the season that have been fixed with updates, is that the casing on one of our NEO motors completely broke off during a match. I guess an opponent hit us hard and something from their robot tore off the case, which we didn’t get a penalty for but that’s not important. The motor still drives fine but for the time being we just taped the case back on. Other than that, everything has been really nice, and the decreased weight allowed us to do swerve drive this year with 4 NEOs for the driving motors.

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#35

Thanks for the data. It will really help teams implement systems with these motors correctly. Can you please update your plots so the axes are all constant? The plots are slightly deceiving right now because each set of tests are plotted against unique scales rather than against a common set. Changing it will make it easier for teams to understand the trade-offs between the various current limit settings.

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