qdd100 beta developer kit


In stock

SKU: qdd100_beta_devkit Category:


This is the beta kit for the mjbots qdd100 quasi-direct drive brushless servo.


  • Peak torque: >=12.5Nm (<1s)
  • Continuous torque: 2.5Nm (indefinite, 20C ambient lab, no airflow or heatsink)
  • Peak speed: 2,000 dps @ 24V
  • Backlash: +- 0.2 degrees
  • Weight: 470g
  • Control rate: 40kHz
  • Mechanical – CAD drawing
    • Outer diameter: 100mm
    • M3 fixed mounting bolt pattern on front and back
    • M3 mounting bolt pattern on output with M4 dowels
  • Voltage input: 10-34V
  • Communication: 5Mbps CAN-FD
  • Power connector: 2x XT-30
  • Data connector: 2x JST PH-3
  • Open source motor driver and firmware with programming port and CAN bootloader: https://github.com/mjbots/moteus

In addition, this is a developer kit that includes everything you need to power up and operate the device:

  • fdcanusb USB to CAN-FD adapter
  • DB-9 to JST PH-3 cable for CAN communication
  • 24V power supply with XT30 connector
  • Spare XT30 and JST PH-3 connectors
  • Brackets and bolts for mounting to a table and a demonstration output “horn” with hole for 1 inch tube
  • USB STM32 programmer w/ moteus JST-ZH6 connector

The expected retail price of the qdd100 is $649, so this is a great deal!  You get the qdd100, an fdcanusb, and a power supply all for less than a qdd100!


Support / questions:

NOTE: This is a BETA product. There will be rough edges, possibly lots of them. The documentation isn’t great / is non-existent, the firmware has not seen wide use, and the hardware may be unreliable. You’re OK with that, and don’t mind providing feedback on how the servo works and how it could be improved. Legally, this beta product is provided AS-IS, without any express or implied warranties, including but not limited to warranties of merchantibility, fitness for a particular purpose and non-infringement.

Additional information

Weight 1.8 kg
Dimensions 31 × 23 × 15.5 cm