Closed loop stepper motors -- very impressive

I bought some "closed loop stepper motors". Experimenting with what they can do. I'm impressed by their power, ability to get back in sync, and less stringent real-time constraints for driving them.

More tech stuff:

[marcoschwanenberger]

On my Jointer/Planer combination machine I had to crank the table all the way up and down if I switch the machine, because the dust shroud has to flip under the cutterhead.
I replaced the Handwheel with a 1.2Nm closed-loop-stepper. Controlling it via Arduino and the huge advantage of the closed loop stepper here is:
I also have a display connected that shows Theoretical Position to 0.1mm. And since the stepper doesn't lose steps, I can really count on that. I essentially have a digital readout with position control (normal and fast travel and a 0.1mm button).
Now I don't have to hand-crank anymore, its way faster to switch the machine around, I don't have to bend down (The button is higher up than the hand-crank) and the machine is also way more accurate. The original scale was 1mm accuracy. Now I can thickness down to 0.1mm accuracy - repeatably!

[mrkattm]

I used closed loop steppers on my home made CNC router, I couldn't be happier with the way it performs and it was so easy to do.

[theinfernalcraftsman]

Used to use those on home built CNC machines . In the past you had to buy double ended stepper motors and add the encoder to it. They have fallen out in favor of DC servo motors now. Much cheaper and easier to do this stuff now than it was 15 years ago. And steppers are far stronger today than they usded to be.

[havenview]

You can get NEMA planetary gearboxes that will fit right on the end of that stepper for a bunch of extra torque
Your speed seems high enough to still have it operate quickly enough

[fuzzydk]

6:55 another option is a stepper controller with a build-in motion controller, f.eks. tmc5160. You just tell when to go and how fast via SPI or UART and it does all the ramping. As long as you don't to synchronous the motion of several motor, like for a CNC, they are easy to use

[jonwally]

I've used a brand of closed loop steppers, ClearPath by Teknic. They allowed for tuning once mounted and all hardware was attached so they could run at their fastest. They were pretty cool to work with.

[JustinDavidow]

For a single motor: this form of closed loop steppers is great. For any multi-axis CNC, the "reaction" time means that the absolute position of the end effector is unknown, as the controller on one axis may already be there, while the other is "making up missed steps". Tracing an arc (for example) with two of these, when pushed anywhere near their limits, will result in inconsistent and difficult to reproduce behavior.

[davebullard]

Thank you. So much quieter too. This is incredibly useful and I'll be buying a couple of these in the near future. I'm capable of goggling "closed loop stepper motor". I wouldn't mind buying them from an affiliate link tho...

[JeffGeerling]

That fun little Pi heatsink looks like it's about to take flight!

[donaldklopper]

Oh man more homework for me now. This might solve several challenges I have with traditional stepper motors in my projects. The additional cost is a pity, but might be a non issue due to the additional complex scenario accuracy. Thanks for making this video.

[defenestrated]

Yes doing small+deep on a CnC is tricky, but you can make many very precise thin gears and glue them together

[garys]

I upgraded my CNC machine to Teknic Clearpath SDSK closed loop steppers. They’re cheaper than servos, but they can be driven with 5V signals. They do require separate 75V DC power supplies. My machine is WAY more powerful and performant, and it doesn’t lose steps. If I have a crash and it does, the controller gets feedback and stops. There are other versions of the motors and they’re easy to control using a Raspberry Pico with PWM or frequency positioning. They’re just amazing. I have some videos of my automatic height dustboot that uses one of those.

[adamsiwek]

Those with a magnet, have a Hall effect encoder. 12 -15 bit so more accurate than most optical.

[vasyapupken]

9:07 - for a rougly the same price (little bit higher) you can get an integrated step-servo in nema 23-24 size. same performance but with 2-3Nm torque. look for IHSS57 type.

as for terminology - "servo" is not a motor type it's a drive type. so any motor with closed loop control is a "servo".
closed loop AC motor - AC servo,
closed loop DC motor - DC servo,
closed loop stepper motor - stepper servo.
saying that servo is better than stepper is incorrect because stepper can be a servo too )

[wessss]

Never get here this early. Happy you got your channel back so quick. Really good video. Might be interesting to see these closed loop motors in more "compliant" uses. But would need to overcome the "out of sync" failure. Might be better to have a seperate encoder and handle error correction in the microcontroller.

[gielb]

from a controls perspective its still a good idea to provide higher order motion profiles in closed loop control systems due to higher order vibrations in the rest of the system if you have a more complex/sensitive system. It will also limit overshoot and such, though I am curious as to how these steppers have their controllers tuned and if you could change them to adapt to your given loads/motion profiles.

[newmonengineering]

I like servo steppers, they are a bit more expensive but they are easy to use and perform very well.

[UTubeGuyJK]

I think we all wish you had a cnc AND a 3d printer. Not because you need them to make things obviously, but because the rest of us have to rely on those things for our projects. If you had those, I can only imagine all of the awesome things you would discover and share with us about making them work better :)

[scottduckworth]

My current project involves closed loop stepper motors with a discrete driver, but I'm tapping into the motor's encoder signal with a microcontroller timer peripheral so that it always knows the position of the motor, even when it stalls. I want to avoid the condition that you demonstrated where the motor stalls too far into the "overload" range and the driver shuts down, then needs a power cycle to recover. I'm just having the microcontroller send steps in the direction of the stall to keep the driver outside of the "overload" range. So far I've been testing with a 4 Nm NEMA24, but I just got a 12 Nm NEMA34 to evaluate... That thing is a beast!

[teitake]

I have no knowledge about electronics and motors but it's still enjoyable and facinating.