NoMi Locus: DC Servo kit…

NoMi Design has been hard at work creating a CNC capable DC Servo Motion Controller.
Based on an earlier design for the “Topology of Dubai” project, the new drive combines an easy to assemble through-hole kit paired with smarter software and an expansion port for increased functionality. Measuring in at just 85 by 50mm, it may be small but this contender is no lightweight.

Power Side Specifications:

  • 200 Watt capable H-Bridge output
  • Up to 90 volts and 8 amps
  • Single power source for under 36v
  • On-board 12v power regulation
  • On-board bulk capacitance
  • zobel network protection
  • Fast fly-back diode protection
  • L6384 gate drivers with deadtime

Logic Side Specifications:

  • Atmega8/88 MCU @ 16Mhz
  • Fast, hand coded assembly loops
  • On-board 5v power regulation
  • Stack-able expansion header
  • 6 Pin serial header for tuning
  • Twin Status LEDs

To do list:

  • Add potentiometers for PID tuning
  • Design Arduino interface shield
  • Design RS485/DMX network shield

RS485/DMX512 multi-drop network stackable expansion shield shown on left.

Previous design viewable at

These kits will be on sale here in a few months time. Some soldering required, batteries not included. Not suitable for voltages under 12…

The latest information and a progress update are now online here:

22 Responses to “NoMi Locus: DC Servo kit…

  • Hi. My name is Cemal.
    I want information about DC Servo kit.
    How many is the DC Servo kit ? Can I pay use paypal ?
    Thank you.

  • Hi Cemal,

    We haven’t set a price yet as research and development is still ongoing.
    I’ll email you when that time approaches, until then keep watch as updates will be arriving soon…


  • Wow, great work. I will eagerly await release of the kit.
    Do you plan to make source available under GPL when complete?

  • Hi George,

    Yes, the source will be available under GPL when it’s complete, it will likely be a combination of inline assembly and GCC, portability is a top propriety. The PIV structure is currently undergoing refinement and I will be posting a status update in the next few days.
    In the meanwhile, we have released the inline assembly function for decoding the quadrature rotary encoder:


  • Hi……….

    we have problem to use this controller on 1kw dc servo and 1024ppr encoder kindly guide us for setup or tunning software.

  • Hi Rupesh,

    This controller is not yet available for sale. Which controller are you referring to?


  • This could be awesome.
    Building a small CNC machine at the mo and if the boards were available in built or kit form i’d be interested. Don’t understand the electronics but could solder it up if all there. How would you go about using it? will instructions for a numpty like me be available? looking for something EMC compatable for use with 24V DC motors

  • Hi Graeme,

    We will have well detailed assembly and use instructions, in video as well as written form. The drive will accept standard step and direction input so it will work with EMC as well as MACH3. It is being design to work at up to 90v so your motors will be compatible. We are looking into the feasibility of providing a fully assembled variant in addition to a kit.


  • I am interested too in this amazing project.
    If this is still going on, please include me to get a DC Servo Kit .

    Thank you for sharing.


  • Hi Vince,
    It’s still ongoing but our attention is currently on production of the TriggerTrap as well as another (top secret!) project. I expect it will be a little while before we get back to work on the DC Servo Drive. We are planning on porting it into the Arduino space for extra fun!

  • I have rebuilt an old Bridgeport with 2-120VDC 7A (X Y… Z not done yet)brushed motors with single ended encoders. I’m looking for a way to control this. Gecko only goes to 80VDC. Will yours work???
    Thank you

  • Hi Bill,
    I have yet to test the design at higher voltages but the design goal is to support up to 150v. When my attention returns to this project I will be changing the RC snubber on the output to an LC snubber as the current iteration thermally dissipates more than I would prefer while in locked anti-phase mode.
    The short answer is yes, it will, when it’s done!

  • This is great and I thank you in advance for doing this project. I’ve been able to scrounge up a few servo motors with encoders but it’s like pulling teeth to find information on how to make a driver so I can use them. There is a driver project published out there which apparently works OK, but the provider of the crucial link – the programmed chip – is sticking with an odd “gypsy” way to acquire it which keeps me from pulling the trigger.

    I’m eagerly looking forward to the launch date.

    One question – I’m assuming from looking at your previous driver page that you will be publishing board, schematic and code so the driver can be completely built if a guy has the right stuff. Is that the case? That would be great. I see that that other project included Eagle files which I think is another great idea. I may still just purchase kits, but even if I don’t you can count on a donation for publishing all that critical project data when the day comes. Be sure to include a button to do that 🙂

  • Hi Vincent,

    We are currently working on the Servo drive, preparing some hardware and software which will be open source when complete.
    There is still much work to do but it is the primary focus and we will be posting an update soon.


  • Hello,
    (Sorry i posted this same thing in another spot of blog, it should have been here. :))
    Looking at building a 4th axis in about a few weeks maybe, and thought this drive might be what i need without breaking the bank.How is the progress going. This looks very promising.


  • Great job!
    We are waiting for final “TaDaaaa!” and documentation offcourse 😉

  • i want to make dc servodrive for pharma labeling and textile weaving machine. for good torque and resolution. recently i am using stepper drive .so whether it is possible to use same driver for dc servo motor. so pl give me some technical hint and advice for devlopment

    pl reply fast….

  • @krazatchu
    top project. is still alive? is any posibility to get the boards? thanks a lot

  • I’m very happy you are doing this! It should be a great success! Let me know when it’s ready.
    Did the version you built for the “Topology of Dubai” project work well? I will try that one out if I run out of time.
    Best of Luck!

  • This is one of those projects I’m never completely satisfied/finished with.

    In it’s current stage as of now, it is through-hole kit, an Arduino Nano shield, much bigger than the Arduino Nano (I call it nano underpants).
    The drive has complete isolation between the power side and the Arduino side, including current feedback.
    There are a row of potentiometers for tuning, this eliminates the need to connect a computer for setup.

    OK, I’ll just append a picture of it to the bottom of the blog post here:
    If your interested I could calculate a price and write up some instructions for assembly.

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