Open-source hardware from Joga

Joga Neck

A 2-DoF active camera neck for the Unitree G1

Two DYNAMIXEL servos point an RGB camera so the G1 can keep the ball in view while it plays. This page covers everything you need to build one.

Get the files Build guide
3D model of the Joga Neck with the OAK-1 W camera on top of two DYNAMIXEL servos and white printed brackets
±90°
Yaw range
20° / 90°
Pitch range, up / down
≈178 g
Total mass
0.93 N·m
Stall torque per axis

Parts

QtyPartNotes
2DYNAMIXEL XC330-M288-TYaw and pitch servos, 5 V.
1ROBOTIS U2D2USB interface for the servos.
1U2D2 Power Hub BoardPowers the servo bus.
1DROK 12 V to 5 V converterSteps the G1's 12 V down to 5 V.
1Luxonis OAK-1 WCamera.
1Locking USB-C cableCamera to your computer.
–USB cable, 2× DYNAMIXEL 3-pin cables, XT30 plug, 16–18 AWG silicone wireWiring.
–M2 screws (included with the servos), 2× M4 × 10 mm screwsFasteners.
4Printed partsTorso Mount, Yaw-Pitch Bracket, Output Bracket, Camera Mount.

The full list is in BOM.md. The 12 V XC330-T288-T fits the same parts and removes the need for the converter.

The Unitree version of the Joga Neck, with two Unitree J288 servos under the OAK-1 W

Unitree version

We also have a version with two Unitree J288 servos. They run directly on the G1's 24 V, so it needs no converter. It shares the Torso Mount, camera, and kinematics with the DYNAMIXEL version. The cheaper plastic S288 also fits, but it is less durable and only takes 12 V.

CAD Files

The STLs are already in print orientation. Start from the Bambu Studio 0.20mm Standard profile and change these settings:

MaterialPETG (PLA also works)
Wall loops4
Sparse infill25%, gyroid
SupportsTree (auto)

Assembly

The arrow shows how each new part goes in. New printed parts are orange.

  1. The yaw servo slides into the top of the Torso Mount from the front
    1

    Yaw servo into the Torso Mount

    Slide the servo in from the front, output axis vertical, and fix it with 2× M2 from the back.

  2. The pitch servo slides into the pocket of the Yaw-Pitch Bracket
    2

    Pitch servo into the Yaw-Pitch Bracket

    Slide the second servo into the bracket, output axis sideways, and fix it with 2× M2.

  3. The Yaw-Pitch Bracket with the pitch servo slides onto the yaw servo horns from the front
    3

    Bracket onto the yaw servo

    Slide the bracket onto the yaw servo so its arms straddle both horns, then screw it to both horns.

  4. The Camera Mount sits on top of the Output Bracket
    4

    Camera Mount onto the Output Bracket

    Screw the Camera Mount to the top of the Output Bracket with M2 self-tapping screws from below.

  5. The Output Bracket and Camera Mount lower onto the pitch servo horns from above
    5

    Output Bracket onto the pitch servo

    Lower it onto the pitch servo so the arms straddle both horns, then screw it to both horns.

  6. The OAK-1 W slides into the Camera Mount with the lens facing forward
    6

    Camera onto the Camera Mount

    Seat the OAK-1 W lens forward and fix it with 2× M4 × 10 mm from the back.

Mounting on the G1

The G1 torso below the neck, with two red and two blue cover screws circled
  1. Power the robot off and remove the two red and two blue screws.
  2. Lift off the front neck cover and disconnect its microphone cable. The cover and red screws stay off.
  3. Fasten the Torso Mount with the two blue screws through the holes in its back.

Wiring

Use 16–18 AWG silicone wire for the power runs, and leave enough cable slack for the full range of motion.

Use a locking USB-C cable for the camera. A plain plug will eventually break the OAK-1 W's USB port. In a pinch, zip tie the cable through the strain relief holes in the Camera Mount.

Files

STLs STEP Onshape CAD URDF Bill of materials GitHub repository

Citation

@misc{joga2026,
  title        = {Joga: Learning Agile Humanoid Soccer Skills with Active Vision},
  author       = {Narula, Avinash and Nguyen, Khai and Fey, Nolan and Parsuram, Venki and Marangola, John and Peticco, Martin and Agrawal, Pulkit},
  year         = {2026},
  howpublished = {\url{https://joga.csail.mit.edu/}}
}

Released under CC BY 4.0.