Precision motion control: ODrive Servo? Trinamic Stepper? Chinese Hybrid?

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  • Опубликовано: 20 янв 2025

Комментарии • 384

  • @aarondcmedia9585
    @aarondcmedia9585 6 лет назад +181

    Stepper monsters. Dancing Pepe. Overheat shrink. Concerned kermit (I am sure I missed even more).
    You have outdone yourself this time, simply outstanding. Chapeau!
    I fully encourage the option of "why not all of them" when presented with multiple choices of CNC projects, look forward to see their construction.

    • @SuperLuckyLad
      @SuperLuckyLad 6 лет назад +7

      Laser engraved oscilloscope screen?...lol

    • @dimitar4y
      @dimitar4y 6 лет назад

      Who's that pokemon!?

    • @nickstanley5064
      @nickstanley5064 6 лет назад +1

      Alucard Pawpad, it's Pikachu!!!

  • @MB-hs4vp
    @MB-hs4vp 6 лет назад +6

    Looking forward to the builds. Also, it's nice to see a video listing the pros and cons of each of the normal driver flavors instead of just servo vs stepper.

  • @AppliedScience
    @AppliedScience 6 лет назад +239

    Good stuff! You may be interested in the Clearpath servo motors with integrated controller from Teknic.

    • @reps
      @reps  6 лет назад +48

      Yes, I've seen that in your Bullet Time video, very cool but very pricey :L

    • @gamerpaddy
      @gamerpaddy 6 лет назад +11

      how about Mechaduino? can be attached to any stepper that has its shaft visible on the backside to put a small diametrically polarized magnet on it. also opensource.
      or VESC which is opensource too, made for up to 50v 240A brushless motors and supports hall/encoder feedback.

    • @extraace
      @extraace 6 лет назад +5

      The thing has put me away from clearpath is lack of encoder outputs. I know they're meant to be direct stepper replacements but then you might as well just keep the steppers. I have a big (4500)kg mill I switched to linuxcnc. Was considering clearpath for the 4th/5th axis, but you get more for the money with DMM servos.

    • @Jay0neDE
      @Jay0neDE 6 лет назад +10

      whoa nerd royalty in the house. greetings Ben.

    • @Thefreakyfreek
      @Thefreakyfreek 6 лет назад

      i was going to say that good on you both

  • @DevilsHandyman
    @DevilsHandyman 6 лет назад +167

    I love the way your carbonize the wires to improve their efficiency. ;)

  • @xDevscom_EE
    @xDevscom_EE 6 лет назад +16

    That's exactly how I used thermal-shrink tube yesterday at work :)

  • @emilen2
    @emilen2 5 лет назад +2

    10:12 That's a very beautiful layered musical chord your motors struck! I might sample that.

  • @Sigmatechnica
    @Sigmatechnica 6 лет назад +5

    I love how projects to make cnc kit to make stuff become more importent/interesting than the stuff you needed a cnc machine for to start with :D

  • @microdesigns2000
    @microdesigns2000 5 лет назад +3

    5:45, yes I read that monster datasheet. Overwhelming is a good adjective. I look forward to using this Trinamic chip set.

  • @swandonovan
    @swandonovan 6 лет назад +16

    Man, I love your videos. Thanks

  • @AiswaranDevaraj
    @AiswaranDevaraj 6 лет назад

    for some reason this channel is soothing to watch i dont know why and some of them i dont even know what they are

  • @alexandrepv
    @alexandrepv 6 лет назад +3

    That is very nice field-oriented-control on those brushless motors! Amazing! And for a fraction of a fraction of the cost!

  • @Tuffenough4u
    @Tuffenough4u 4 года назад +2

    DAMN! I can't believe I didn't know about this Odrive before now. I've an active RC enthusiast for 30 years now, and was into high end 4x4 short course and buggy racing for the last 10. That being said, I'm a hobbywing guy. Hobbywing is the only manufacturer that I know of that offers G2 motors that utilize two separate encoders. This was a real advancement over the rest of the rc motor world, as having two separate hall sensors allowed them run the low resolution sensor for lowspeed operation. Before the invention of these type motors, the speed control (ESC) would just turn the sensor off at low speeds so that it would prevent "cogging" (the bucking and hanging up due to low torque when going from 0-moving) Once the ESC sensed that the motor was running past a certain RPM, it would then turn on the sensor mode for high resolution control and superior efficiency over non-sensored motors. So I guess what I'm getting at is I wonder if it's possible to take one of the G2 Motors that have dual sensors and get write code needed for a redundancy algorithm setup with one of these drivers?.... Hmmm. Got my head spinning now!

  • @dimitar4y
    @dimitar4y 6 лет назад +4

    I love the chinese hybrid the most, with that awesome awesome driver that adjusts current and detects step loss. I like the idea it just interrupts, instead of trying to recover (and doing something awful). You could hook that up to a custom program to re-home the machine and continue.

  • @AndersJackson
    @AndersJackson 6 лет назад

    Your videos gets better and better each time I watch them. :-)

  • @ДенисЗайцев-э1ф
    @ДенисЗайцев-э1ф 5 лет назад +2

    I use dynamotion kflop. Real closed loop. From now on I feel joy and calm.
    No matter how much work time, always accurate coordinates.
    Stepper motor driver Leadshine, most silent and powerful.
    42 volts power sourse.

  • @FranklyPeetoons
    @FranklyPeetoons 6 лет назад +48

    I like these comedy videos masquerading as engineering videos. Dry as a bone!

  • @metricstormtrooper
    @metricstormtrooper 6 лет назад +71

    I can only understand 10% of what you talk about, but its really interesting and entertaining anyway.

    • @res1492
      @res1492 6 лет назад

      No...i just thick!!

    • @metricstormtrooper
      @metricstormtrooper 6 лет назад

      G510Gamer What accent?

    • @metricstormtrooper
      @metricstormtrooper 6 лет назад

      res1492 That was unnecessary.

    • @res1492
      @res1492 6 лет назад +2

      Ermm...thanks for caring but i really am thick!!...im 42 and just figured out how to tie my shoelaces yesterday

    • @tylouww.1915
      @tylouww.1915 6 лет назад +1

      I think its a german accent, because i am Form Germany and i can hear it

  • @BuilderV8
    @BuilderV8 5 лет назад

    What a fantastic demonstration of control and description. Thank you.

  • @divyajnana
    @divyajnana 6 лет назад +2

    just found your site, super funny and useful at the same time, subscribed, THANK YOU!

  • @BergRD
    @BergRD 6 лет назад

    Great video! The 'Press enter and hide!' was superb! :D

  •  5 лет назад

    It's a good use of your time! Keep doing what you love!

  • @mikemulligancopilotdesigns9904
    @mikemulligancopilotdesigns9904 4 года назад

    Man your videos are so great! Thanks for sharing!

  • @georgevukelich607
    @georgevukelich607 5 лет назад

    We just built a 6kW pulsed laser system at work to weld proprietary dissimilar metals. We're also using a 1kW psed laser to abate the weld edge of the metal.

  • @armandgeorges4380
    @armandgeorges4380 6 лет назад +1

    The best channel on RUclips!

  • @mr.sandman4782
    @mr.sandman4782 6 лет назад +2

    CANT WAIT for the project video

  • @amateurcarolina
    @amateurcarolina Год назад

    Neat what you're doing with your scope screen!

  • @Egon.Sorensen
    @Egon.Sorensen 6 лет назад +1

    Wow! Amazing visual effects - it really blew me away + the sound *lol*
    Can you do a video on what you are using to edit your videos - they look soo good! Thumbs up!
    Thanks so much for sharing such superb work. (Glasses and goggles are cool - they keep your looks up ;-)

  • @gearscodeandfire
    @gearscodeandfire 4 месяца назад

    Just found this channel and it is wonderful

  • @iosonogerva1989
    @iosonogerva1989 6 лет назад +9

    I used a lot of those chinese closed loop stepper at work and i have mixed feeling. On one hand they are very convenient but in the other hand the factory tuning is not suitable for all uses.
    For example, the PID that control the feedback, can (and will) cause oscillation and imprecise positioning on fast movements due to overshoot, the auto tuning of the power is so hit and miss that i discovered that the best solution i to disable it (even when it's disabled it seem to set its parameters at boot resulting in a motor that does not have consistent torque between boots).
    All of those problems can be solved configuring the parameters but good luck in sourcing the correct software for your specific controller (even the manufacturer can't send me a working version of the software that's not in chinese and untranslatable).
    BTW they seem to be all manufactured (or cloned) by a company named LeadShine and they even exist in the more convenient integrated form with the driver mounted on the side of the motor.
    I have some controllers with the chip marking readable, if you want some info on the chip i can send you a photo

    • @hyperhektor7733
      @hyperhektor7733 6 лет назад

      you could just upload the images to imgur.com/
      so we could all see the info. :)

  • @megapwn333
    @megapwn333 6 лет назад +1

    I'm working with the TMC5161 right now the brand new motor controller from trinamic

  • @DanielRowe
    @DanielRowe 6 лет назад

    Looking forward to seeing these machines.

  • @avejst
    @avejst 6 лет назад +1

    Thanks for sharing 😀👍
    You always find a way to use your time, this way or another project way..😉

  • @avaruusvektori
    @avaruusvektori 4 года назад

    Nice review of DIY options, Marco!
    PS have you noticed Finnish company's Granite Device and their IONI drive? Those drives are quite flexible and can do almost everything of all the drives reviewed here in single model. Story of that company started from hobby CNC project, very much like yours :)

  • @xaytana
    @xaytana 6 лет назад +3

    Hobby rc motors are designed to spin very fast, especially those used in hobbyist aviation; do you think having a reduction transmission, probably a harmonic or hypocycloidal for almost no backlash and efficiency, the setup would have holding torque? Having the encoder after the reduction transmission could also improve accuracy.

    • @flarosantana6330
      @flarosantana6330 2 года назад

      Putting the the motor through a worm and spur gear would get rid if back drive and solve the holding torque issue. Then could put the encoder after the gear system as well. The gears would have to interface perfectly for no backlash however.

  • @modfabcom-au9909
    @modfabcom-au9909 6 лет назад

    Love your work Marco !

  • @tobystewart4403
    @tobystewart4403 6 лет назад

    Great information and style. The Odrive is the madness.

  • @GeorgeTsiros
    @GeorgeTsiros 3 года назад

    those gimbal motors are _gorgeous_

  • @SAMETELMACI
    @SAMETELMACI Год назад

    ı have a vibration issue within close loop control velocity control mode can you help me

  • @alexherrerag6997
    @alexherrerag6997 5 лет назад +1

    1:12 this sounds comes from stepper motor feddback vibrration?

  • @wilsonmura5930
    @wilsonmura5930 6 лет назад +5

    Great vid! & also could you please pass along the links for the gimbal motors and encoders?

  • @KaspersMC
    @KaspersMC 6 лет назад +1

    upper right corner 1:12 ?
    first i believe it was a dancing bird... but No (1:27), Maybe some Cool display there show Sound ?

  • @botak333
    @botak333 Год назад

    So do u recomend servo motor with odrive for cnc?

  • @jon_raymond
    @jon_raymond 6 лет назад

    Thanks for such a great comparison!

  •  6 лет назад

    Thank you, the tmc5160 is exactly what I need for my robot. Progress is moving so fast, I checked all the Stepper driver 6 month ago, and somehow missed the tmc5160. If I find somewhere time I make a driver like you suggested (no promise lot of other projects).

  • @rikilshah
    @rikilshah 6 лет назад

    Your raw humor is certainly a treat to ears. That concerned Kermit though.

  • @FilmFactry
    @FilmFactry 6 лет назад

    Excellent information, very helpful!

  • @bitluni
    @bitluni 6 лет назад

    Where dit you get the laser from ?

    • @reps
      @reps  6 лет назад +1

      A person! He has a few more of those and wanted me to make a few CC drivers in exchange for this one 😍

  • @DodgyBrothersEngineering
    @DodgyBrothersEngineering 6 лет назад

    Giving you a like and a comment because you have the right amount of geek going on.

  • @robertanderson6471
    @robertanderson6471 5 лет назад

    Thank you for building something real quick

  • @davidprock904
    @davidprock904 5 лет назад

    I got plans to build my own 3D printer, also designing my own stepper motor, godly strong and insane accuracy and precision.
    The design is still just in my head, and a lot of gearing is involved. And motion conversion, that I could use a bit of help with

  • @R3DE3MER
    @R3DE3MER 5 лет назад

    love that kermit in the background at 10:12

  • @brainfornothing
    @brainfornothing 6 лет назад

    Wow ! Ben Krasnow is in the House ! I made my own drivers, very simple schematics, for my first and second CNC's, in the late 90's, before eBay, Hehehe! My next CNC's will be a little PCB mill/LED laser engraving and a robust CNC router; this video gave me a good solution for the last one, with thick steel frame like my second CNC, maybe 400x400 mm, to use in wood, aluminium and steel, using soft passes and refrigeration. What is your goal ? Thanks for sharing !

  • @IlhamDefraN
    @IlhamDefraN 4 года назад

    in choosing stepper motor, is it better to use small face plate but long (let say long NEMA 17), or big face plate but short (let say short NEMA 34)?

  • @elcidbob
    @elcidbob 4 года назад

    Why aren't optics used for positioning? Sensors have pixel sizes in the under 30 ųm² (yes, I know that's not a mu but it's the closest symbol I could find on my keyboard). That, when combined with something like facets cut to a certain length at a given angle could be used to sense the position of reflected light to an extremely precise degree, especially when you start leveraging the power of cosine in this setup (that is don't have the reflected light hitting the sensor surface orthogonally, angle will be limited by optical well depth, but that's mitigated with microlenses to increase the sensed length to a definitely detectable size/ somewhat easy to manufacture).
    I expect that people smarter than me have considered and rejected something like this, so if anyone can provide some insight as to why, I'd be interested to find out.

  • @nubletten
    @nubletten 2 года назад

    Put 3 axis on this seems like a kool feature or an ad in board for the third axis.

  • @joshwarner5676
    @joshwarner5676 6 лет назад

    This is pretty much the same conclusion I came to with the odrive vs a hybrid stripper system when considering for my next build. Laser time with the odrive.

  • @thatoneguy99100
    @thatoneguy99100 5 лет назад +4

    Can you make a video specifically for the TMC5160?

  • @Tuffenough4u
    @Tuffenough4u 4 года назад

    This is like an opensource RC ESC (speed controller)! The newest Hobbywing G2 capable speed controls like the Pro XE series has all the features you mentioned the Odriver does, such as dual hall sensor control, regenerative braking, etc. I wonder if the creator was a Hobbywing tech defector?! haha

  • @MegaFPVFlyer
    @MegaFPVFlyer 6 лет назад +1

    Maybe I've finally found a use for all the BLDC motors I have lying around!

  • @grantsunday8916
    @grantsunday8916 6 лет назад

    Entertaining and informative. Sehr gut

  • @maliakbulut
    @maliakbulut 4 года назад

    I wonder, what happens if you suddenly release the closed-loop step motor's shaft after preventing its motion few time with a strong hold ??

  • @thomasfolbrecht4067
    @thomasfolbrecht4067 6 лет назад

    The Kermit got me. Another excellent video!

  • @hoffybeefe
    @hoffybeefe 5 лет назад +2

    Hi Marco, newer subscriber here. Love the information and humor! My simple brain has been wanting to make a rotary table for years now (for 3D scanning, maybe some video/photo on the rare occasion, but mostly because it'd be damn cool to learn/have one). But its to hard. Perhaps a pro like yourself could show me... da way!
    Is it possible to have a cheap(ish) device thats CNC controlled to be able to do things like you mention in this video but for a rotary turntable style? Eg do 12 stops around one turn with a pause of 12seconds at each stop. with some kind of ability to make it transition from each turn at a certain speed so as to not "dislodge" something mounted via gravity on the table? And all manner of different ways one may want to make something rotate... stop.. rotate? :)
    Would LOVE a video on doing this. I'd love a servo motor because.. well duh. but the programming side of it is just to much for me.. assuming it would at all be possible? Where's the Google Store App for this dammit! ;)

    • @vilts
      @vilts 5 лет назад

      It's not too difficult, but you got a learning curve ahead, if you don't know background. I guess like with everything, if you know it, it's easy.
      3 dollar arduino controlling stepper driver (any step-dir), which drives the stepper powered rotary table. Arduino has stepper libraries available (start-stop acceleration, speed, distance etc), so it's just few lines of code to get it all moving.

    • @BrilliantDesignOnline
      @BrilliantDesignOnline 5 лет назад

      Mach3 is cheap and 'simple', and you (meaning I) could hand code some G-code to do what you say. I am not too far advance from you, but after you understand G-code not too difficult.

  • @vasyapupken
    @vasyapupken 5 лет назад +2

    closed loop stepper is actually a good choice. all servos has very bad holding torque in compare so it's not because "not tuned".
    even fine tuned proper servo motor must be next size up to have holding torque similar to stepper. (nema23 stepper = nema34 servo)

    • @adfy2307
      @adfy2307 2 месяца назад

      probably you should tune pid regulator in the driver or cnc controller

  • @SergeyAnufrienko
    @SergeyAnufrienko 6 лет назад

    Is it the oscilloscope screen releasing some smoke on 0:25 ?

  • @thecyclingmaker
    @thecyclingmaker 5 лет назад

    hmmmm, that click at 9:56 and yes, a great video, thankyou

  • @wizrom3046
    @wizrom3046 4 года назад

    You said when stepper motors skip a step "it always skips 1.8 degrees" but it's actually 7.2 degrees (360 / 50) because it skips to the next compatible pole of which there are 50 per rotation.
    Also the property of servos and encoders to deflect from the desired position is bad in cnc cutting because that deflection will be caused by the cutting tool forces and the result is poor rigidity. You are better with stepper that have a high holding torque or high torque servo motors and lots of gearing.
    Great vid, and nice humour too! 👍

  • @Ground-Robotics
    @Ground-Robotics Год назад

    why not using a brushed dc motor? As it should hold its position better?

  • @johnstigglet7512
    @johnstigglet7512 6 лет назад +1

    Hi Marco, very interested in the ODrive, and its capability, However not with the hobby motors, bat a connection with the hybrid stepper/ Servo style motor. do you think its possible to these aforementioned motors from tho ODrive?
    Regards Stiggie

  • @ponydown418
    @ponydown418 6 лет назад +1

    The perfect video I was looking for! Danke! If I'm guessing the accent right.

  • @PhG1961
    @PhG1961 6 лет назад

    Waw, absolutely a great video !

  • @brucewilliams6292
    @brucewilliams6292 6 лет назад

    Thank you for sharing your dilemma! :)

  • @MarcusBehrens
    @MarcusBehrens 6 лет назад

    Hi Marco, I have used stepper motors with encoders and gear motors with encoder on the motor shaft. The later gives you very precise control over the movement as the gearbox translates 1 revolution of the motor shaft into 1/100 of a revolution on the gearbox shaft and if you have a resolution of 48 steps on the encoder you already get 4800 encoder steps for one revolution. Have you considered such gear motors? They have much more holding power and power in general and use less amps. They are used a lot in robots. Regards, Marcus from Heidelberg

    • @reps
      @reps  6 лет назад

      Not considered yet, but I definitely will now! Thank you from Hannover :)

  • @ProjectileObjects
    @ProjectileObjects 6 лет назад

    @Marco Reps, What do you mean by medium-sized motors @5:18 with the Trinamic? Was it the same hybrid motor from the "Blue Chinese Hybrid?" I'm trying to build something similar that will support 10Kg suspended weight. Any thoughts?

  • @JoeSmith-wu3yz
    @JoeSmith-wu3yz 6 лет назад

    Good job as always :)

  • @skyhacker6
    @skyhacker6 5 лет назад +1

    0:25 RIP the oscilloscope !!!! smoke, smoke everywhere !!!

  • @milolouis
    @milolouis 6 лет назад +4

    WHAT!! did you just burn your scopes LCD?? Special effects?

  • @douro20
    @douro20 6 лет назад

    I wonder if the Trinamic drivers are made in Erfurt?

  • @Andreas-gh6is
    @Andreas-gh6is 6 лет назад

    I just love your humor!

  • @cedricpod
    @cedricpod 6 лет назад

    I love this video great info and great voice

  • @sergiocardenasreyes7418
    @sergiocardenasreyes7418 6 лет назад

    Amazing video. What controller would you recommend If one wanted to work with a small brushless motor (like the blue beetle you show 8:31) ?

  • @calvin-7540
    @calvin-7540 4 года назад

    Is the stepper motor determines the accuracy of a 3d printer? If yes, what characteristics of stepper motor determine the accuracy of a 3d printer

  • @Z0DI4C
    @Z0DI4C 5 лет назад

    I'm seeing some more usable TMC2160-based stepper driver modules on Aliexpress now. Looks like they're new, although I'm sure it'll be hard to get one for a few weeks due to the whole, uh, quarantine thing.

  • @twistedsocal
    @twistedsocal 5 лет назад

    clear path servos are pretty nice and I believe they have decent holding strength

  • @petergfrazier
    @petergfrazier 6 лет назад

    The Prusa i3 MK3 controller board has trinamic chips integrated into the unit... which is kind of the same as a trinamic motion controller.

  • @Tedlasman
    @Tedlasman 3 года назад

    So, this is another thing I bought that happens to be in video I watched from you.

  • @bringamosa8480
    @bringamosa8480 6 лет назад +1

    5:45 got me cracking up. awesome

  • @theq4602
    @theq4602 6 лет назад +1

    How big do they make Stepper motors?
    How many HP? ft-lbs of torque? I know BLDC motors are torque monsters. That's why many cordless drills and impacts are using them. Great low end grunt energy efficiency and reliability!

  • @TonyLehto
    @TonyLehto 6 лет назад

    What's the laser diode? Where can I get it? Was it expensive?

  • @hello81642
    @hello81642 2 месяца назад

    What would you recommend in 2024 for steppers?

  • @ProtoG42
    @ProtoG42 6 лет назад

    What voltage are you driving those gimbal motors? 22V?

  • @avejst
    @avejst 6 лет назад

    Interesting stuff
    Thanks for sharing 😀👍

  • @umargul5644
    @umargul5644 4 года назад

    Well done sir very useful

  • @MadHatter123456
    @MadHatter123456 6 лет назад

    Thanks a lot! Awesome stuff! Made me think about using an ODrive for my DIY-lathe, but I think I'll stick to my chinese servos for that. If only they could be used with step/direction...

    • @johnstigglet7512
      @johnstigglet7512 6 лет назад

      I think you will find step and direction is available

  • @shobairbashiri9227
    @shobairbashiri9227 3 года назад

    its possible to run 1000 rpm with Trinamic Stepper?

  • @bloodswarms
    @bloodswarms 6 лет назад

    I wonder if this would be overkill for a camera slider.

  • @qedqubit
    @qedqubit 6 лет назад

    the video thumbnail shows an awesome BW-image of an encoder disk,
    that can explain the stepping sequence, and microstepping but also explain binary counting.-but you didn't show it in the video ?

  • @richardpitz6040
    @richardpitz6040 4 года назад

    Have you ever worked with dc dental motors that drive electric dental drills?

  • @ralph638
    @ralph638 6 лет назад

    Take a look at the JMC iHSV57 HybridServoMotors ;) They are also able to stream realtime data about torque, acceleration, speed and position errors which is nice for tuning the PID loops.

    • @Spirit532
      @Spirit532 6 лет назад

      Their holding torque is just sad, especially for the price they want, because you can get cheap servo+drive kits for about $10-20 more that give you 5-10 times more torque.

    • @ralph638
      @ralph638 6 лет назад

      Can you give me a link or hint where to find those cheap dc servo/drive kits?

    • @Spirit532
      @Spirit532 6 лет назад

      You're better off looking yourself, the prices vary wildly and you just pick the cheapest source at the time of purchase. The places to look are eBay and Aliexpress, with the keyword "NEMA23 Servo" or "NEMA34 Servo", but be sure to avoid "Hybrid" and "Stepper" in the listings if you want a true 3-phase AC servo instead of a stepper with an encoder.

    • @ralph638
      @ralph638 6 лет назад

      I searched again but ended with the same result as before (I'm observing real NEMA23 servo prices for some years now) ... there are no other real servos/encoder kits for less than 100€, all you can find are based on simple stepper motors (which explains why they have a high holding torque) and I can clearly see the A/B winding connectors on their drivers. If you find a real cheap servo/driver kit, please give me a manufacturer/product name but I don't think that you will find something in that price range that isn't made by JMC.

    • @Spirit532
      @Spirit532 6 лет назад +1

      The JMC motors end up costing about $100-110 with shipping and customs.
      There are plenty of $120-150 NEMA23 3-phase servos.

  • @matejhilmer7815
    @matejhilmer7815 6 лет назад

    Would it be usable if you built a fast 3D printer with ODrive on X and Y axis? It wouldn't matter very much if Z axis used a normal stepper with trinamic driver, because it doesn't have to move that much.