Build LeKiwi

Steps

16

Subassemblies

10

Hands-on time (sum)

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Critical path

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Your progress · this device

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16 steps have no time estimate; times above are lower bounds.

1. Fabrication
   01

   Print the base, mounts and both SO-101 arms

   Load each STL, auto-rotate and auto-arrange, and enable supports for the wheel hubs (normal) and the modified arm base (tree). 0.2 mm layers, 15% infill, 150 mm/s. Upstream estimates about 34 printer-hours in total. Print the arm plates from SO-ARM100.

   CHECK3 motor mounts and 3 wheel hubs, both base plates, the power-bank holder, Pi case, camera mounts and both arm part sets are printed with supports removed. An M3 nut presses into the controller-mount and holder nut traps.

   Parts in

   • Base plate bottom (base_plate_layer1.stl)printed.base-plate-bottom
   • Base plate top (base_plate_layer2.stl)printed.base-plate-top
   • Drive motor mount (drive_motor_mount_v2.stl)printed.drive-motor-mount
   • Servo wheel hub (servo_wheel_hub.stl, modified VEX VersaHub)printed.servo-wheel-hub
   • Servo controller mount (servo_controller_mount.stl)printed.servo-controller-mount
   • 5 V power bank holder (5v_specific/5v_power_bank_holder.stl); 12 V builds print battery_mount.stl or battery_mount_eu.stl insteadprinted.power-mount
   • Raspberry Pi 5 case top (pi_case_top.stl)printed.pi-case-top
   • Raspberry Pi 5 case bottom (pi_case_bottom.stl)printed.pi-case-bottom
   • Webcam base mount (webcam_mount/webcam_mount.stl); Arducam builds use base_camera_mount.stlprinted.webcam-base-mount
   • Gripper with M3 nut insert for the wrist webcam (webcam_mount/so100_gripper_cam_mount_insert.stl)printed.webcam-gripper-insert
   • Webcam wrist mount (webcam_mount/webcam_mount_wrist.stl); Arducam builds use wrist_camera_mount.stlprinted.webcam-wrist-mount
   • Modified follower arm base (modified_base_arm.stl), optional but recommended if you have not built an SO-100/101 yetprinted.modified-arm-base
   • SO-101 follower arm parts (SO-ARM100 STL/SO101 follower plate)printed.so101-follower
   • SO-101 leader arm parts (SO-ARM100 STL/SO101 leader plate)printed.so101-leader

   Tools

   FDM printer (tested on Bambu Lab P1S), PLA filament

   Torque

   —

   Time

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   After

   Start

   Source

   github.com

2. Compute
   02

   Flash Raspberry Pi OS and enable SSH

   Write Raspberry Pi OS (or Ubuntu) to the microSD with Raspberry Pi Imager, boot the Pi and enable SSH (`sudo raspi-config`, Interfacing Options > SSH). Wired version: skip this step and run everything on the laptop.

   CHECK`hostname -I` on the Pi shows its IP and `ssh <user>@<pi-ip>` from the laptop logs in.

   Parts in

   • Raspberry Pi 5, 4 GBcompute.rpi5
   • microSD card (Raspberry Pi OS)electronics.microsd

   Tools

   Raspberry Pi Imager, Laptop on the same network

   Torque

   —

   Time

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   After

   Start

   Source

   huggingface.co

3. Arms
   03

   Build the SO-101 follower and leader arms

   Follow the SO-101 guide (see therobotstudio/so-101): set leader IDs with `lerobot-setup-motors --teleop.type=so101_leader --teleop.port=<port>`, then assemble both arms joint by joint with M2x6 and M3x6 screws. Leave the follower off its own driver board: on LeKiwi its chain plugs into the single board on the base together with the wheels.

   CHECKBoth arms move freely by hand through every joint, and the leader's six motors answer with IDs 1-6 on its own board.

   Parts in

   • Feetech STS3215 servo, 7.4 V: SO-101 follower (on the base) + leader (on the laptop), 6 + 6actuator.sts3215-arm
   • SO-101 follower arm parts (SO-ARM100 STL/SO101 follower plate)printed.so101-follower
   • SO-101 leader arm parts (SO-ARM100 STL/SO101 leader plate)printed.so101-leader
   • Motor control board: Waveshare serial bus servo driver (one on LeKiwi for arm + wheels, one for the leader)electronics.bus-servo-adapter
   • DC power supply, 5 V, 5.5x2.1 mm barrel (leader arm on the desk)power.psu-leader

   Tools

   Phillips #0, Phillips #1

   Torque

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   Time

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   After

   01

   Source

   huggingface.co

4. Compute
   04

   Install LeRobot with the LeKiwi extra on Pi and laptop

   On both machines: install LeRobot per the installation guide (conda env, Python 3.12, `git clone https://github.com/huggingface/lerobot.git`), then `pip install -e ".[lekiwi]"` (Feetech SDK + ZeroMQ).

   CHECK`python -c "import lerobot.robots.lekiwi"` runs without error on both the Pi and the laptop.

   Parts in

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   Tools

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   Torque

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   Time

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   After

   02

   Source

   huggingface.co

5. Mobile base
   05

   Assemble the three wheel modules

   For each module: drive servo into the motor mount with 4 m2x5 tapping screws; mount onto the bottom base plate with 4 m3x12; wheel hub to omni wheel with 2 m4x12; servo horn to wheel hub with 2 m3x16; horn to the servo with 1 m3x6.

   CHECKAll three wheels sit at 120° spacing, spin freely by hand with no wobble at the hub, and the robot rests level on all three.

   Parts in

   • Precision screwdriver setother.screwdriver-set
   • Feetech STS3215 servo, 7.4 V: 3 wheel drives (continuous rotation, IDs 7 left / 8 back / 9 right)actuator.sts3215-wheel
   • Drive motor mount (drive_motor_mount_v2.stl)printed.drive-motor-mount
   • Servo wheel hub (servo_wheel_hub.stl, modified VEX VersaHub)printed.servo-wheel-hub
   • 4 in (100 mm) omni wheelstructure.omni-wheel
   • Base plate bottom (base_plate_layer1.stl)printed.base-plate-bottom
   • M2 / M3 / M4 assorted screw set (covers m2x5 tapping, m3x6/12/16/20, m4x12 and M3 nuts used in assembly)fastener.screw-assortment

   Tools

   Phillips #1, Hex key set

   Torque

   —

   Time

   —

   After

   01

   Source

   github.com

6. 06

   Bottom plate: servo board and power mount

   Press M3 nuts into the servo-controller mount and the power-bank (or battery) mount and screw both to the bottom plate with 4 m3x12. Fit the servo driver board and connect the three drive servos to it.

   CHECKThe board sits firmly in its mount and each wheel servo cable reaches the board without tension.

   Parts in

   • Servo controller mount (servo_controller_mount.stl)printed.servo-controller-mount
   • 5 V power bank holder (5v_specific/5v_power_bank_holder.stl); 12 V builds print battery_mount.stl or battery_mount_eu.stl insteadprinted.power-mount
   • Motor control board: Waveshare serial bus servo driver (one on LeKiwi for arm + wheels, one for the leader)electronics.bus-servo-adapter
   • M2 / M3 / M4 assorted screw set (covers m2x5 tapping, m3x6/12/16/20, m4x12 and M3 nuts used in assembly)fastener.screw-assortment

   Tools

   Phillips #1

   Torque

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   Time

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   After

   05

   Source

   github.com

7. 07

   Top plate: Pi and follower arm

   Put the Pi 5 in the case bottom and snap on the top. Fix the case to the top plate with 2 m3x12. Mount the SO-101 follower with 4 m3x20; the plate has holes for both the modified and the original SO-101 base.

   CHECKThe arm base does not rock on the plate when you push the arm sideways.

   Parts in

   • Raspberry Pi 5, 4 GBcompute.rpi5
   • Raspberry Pi 5 case top (pi_case_top.stl)printed.pi-case-top
   • Raspberry Pi 5 case bottom (pi_case_bottom.stl)printed.pi-case-bottom
   • Base plate top (base_plate_layer2.stl)printed.base-plate-top
   • Modified follower arm base (modified_base_arm.stl), optional but recommended if you have not built an SO-100/101 yetprinted.modified-arm-base
   • M2 / M3 / M4 assorted screw set (covers m2x5 tapping, m3x6/12/16/20, m4x12 and M3 nuts used in assembly)fastener.screw-assortment

   Tools

   Phillips #1

   Torque

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   Time

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   After

   03, 02

   Source

   github.com

8. Electrical
   08

   Power wiring (5 V or 12 V)

   Safety · human-verified required

   5 V: seat the power bank in its holder at the back of the lower plate; run USB-C to DC barrel into the servo board and a short USB-C cable to the Pi, as in the upstream wiring diagram. 12 V: join the battery leads, the 12 V to 5 V converter leads and the DC barrel adapter in the Wago lever connectors, then fix the converter to the bottom plate with 2 m3x16 and 2 M3 nuts. Keep everything unplugged until final assembly.

   CHECKWith a multimeter the barrel plug reads about 5 V (5 V build) or about 12 V (12 V build), and the converter's USB-C output reads about 5 V. Nothing gets warm with the loads unplugged.

   This step can hurt a person or ruin parts. Its instructions need sign-off by a human who has done it before relying on them. Stop and ask if anything differs from what you see.

   Parts in

   • 20000 mAh 85 W USB-C power bank (5 V version: powers the Pi and the servo board)power.power-bank
   • USB-C to DC barrel cable (power bank to servo board)cable.usb-c-to-dc
   • USB-C cable, 2 pcs, 1 ft / 0.5 m (power bank to Pi)cable.usb-c-short

   Tools

   Multimeter

   Torque

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   Time

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   After

   06

   Source

   github.com

9. Mobile base
   09

   Close the base

   Feed the servo board's USB-C to USB-A cable, the 5 V USB-C power cable and the follower arm's servo cable through the hole in the top plate. Mount the top plate on the motor mounts with 4 m3x12. Plug the follower chain into the base servo board so arm and wheels share one bus.

   CHECKThe top plate sits flat on all mounts and no cable is pinched between the plates.

   Parts in

   • USB-C to USB-A cable, 2 pcs (servo boards to Pi / laptop)cable.usb-c-to-a
   • M2 / M3 / M4 assorted screw set (covers m2x5 tapping, m3x6/12/16/20, m4x12 and M3 nuts used in assembly)fastener.screw-assortment

   Tools

   Phillips #1

   Torque

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   Time

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   After

   07, 08

   Source

   github.com

10. Cameras
    10

    Mount the front and wrist cameras

    Webcam option: print the gripper with the M3 nut insert, fit the nut, refit the gripper motor and jaw. Screw the wrist mount on with an M3x12 until it locks into the nut, seat the camera and lock it with 2 M3x35 bolts and nuts in the rear slots. Mount the base webcam at the front of the base the same way. Arducam option: base_camera_mount on the bottom plate and wrist_camera_mount on the static gripper (4 M2x5 tapping screws; camera with 2 M2.5x12).

    CHECKBoth cameras plug into the Pi USB ports, and in the default LeKiwi config they enumerate as /dev/video0 (front) and /dev/video2 (wrist). If they don't, pass `index_or_path` for each camera.

    Parts in

    • USB camera (front base camera + wrist camera)sensor.usb-camera
    • Webcam base mount (webcam_mount/webcam_mount.stl); Arducam builds use base_camera_mount.stlprinted.webcam-base-mount
    • Gripper with M3 nut insert for the wrist webcam (webcam_mount/so100_gripper_cam_mount_insert.stl)printed.webcam-gripper-insert
    • Webcam wrist mount (webcam_mount/webcam_mount_wrist.stl); Arducam builds use wrist_camera_mount.stlprinted.webcam-wrist-mount

    Tools

    Phillips #1, Hex key

    Torque

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    Time

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    After

    09

    Source

    github.com

11. Motor setup
    11

    Set arm and wheel motor IDs on the single base bus

    Safety · human-verified required

    On the Pi: `lerobot-find-port`, then `lerobot-setup-motors --robot.type=lekiwi --robot.port=<port>`. It prompts one motor at a time: arm IDs 6 down to 1, then wheels 9, 8, 7. Connect only the prompted motor each time. Wheel IDs must match position: 7 left, 8 back, 9 right.

    CHECKEvery prompt ends with the motor id set message and no error. Afterwards all nine servos respond on one daisy chain.

    This step can hurt a person or ruin parts. Its instructions need sign-off by a human who has done it before relying on them. Stop and ask if anything differs from what you see.

    Parts in

    • Feetech STS3215 servo, 7.4 V: SO-101 follower (on the base) + leader (on the laptop), 6 + 6actuator.sts3215-arm
    • Feetech STS3215 servo, 7.4 V: 3 wheel drives (continuous rotation, IDs 7 left / 8 back / 9 right)actuator.sts3215-wheel
    • Motor control board: Waveshare serial bus servo driver (one on LeKiwi for arm + wheels, one for the leader)electronics.bus-servo-adapter

    Tools

    —

    Torque

    —

    Time

    —

    After

    04, 10

    Source

    huggingface.co

12. Calibration
    12

    Calibrate follower (on the Pi) and leader (on the laptop)

    Safety · human-verified required

    Over SSH on the Pi: `lerobot-calibrate --robot.type=lekiwi --robot.id=my_awesome_kiwi`: middle-of-range pose, Enter, sweep each arm joint, Enter. The wheels need no calibration. Clamp the leader to the desk and run on the laptop `lerobot-calibrate --teleop.type=so100_leader --teleop.port=<port> --teleop.id=my_awesome_leader_arm` (so100_leader and so101_leader are the same class in lerobot 0.6.x).

    CHECKTwo calibration JSONs exist, one per id, under `~/.cache/huggingface/lerobot/calibration/` on the respective machines.

    This step can hurt a person or ruin parts. Its instructions need sign-off by a human who has done it before relying on them. Stop and ask if anything differs from what you see.

    Parts in

    • Table clamp, 4 pcs (leader arm)other.table-clamps

    Tools

    —

    Torque

    —

    Time

    —

    After

    11

    Source

    huggingface.co

13. First motion
    13

    First motion: drive and teleoperate

    Safety · human-verified required

    On the Pi: `python -m lerobot.robots.lekiwi.lekiwi_host --robot.id=my_awesome_kiwi`. On the laptop, set `remote_ip` in `examples/lekiwi/teleoperate.py` and run `python examples/lekiwi/teleoperate.py`. The leader drives the arm; W/A/S/D translate, Z/X rotate, R/F change speed (slow 0.1 m/s / 30 deg/s, medium 0.25 / 60, fast 0.4 / 90). Start on the floor in slow mode with space around the robot. Keyboard base control needs X11, Windows or macOS with Input Monitoring, not Wayland.

    CHECKThe laptop logs `Connected to remote robot at tcp://<pi-ip>:5555 and video stream at tcp://<pi-ip>:5556`, the follower mirrors the leader, and W moves the base forward in a straight line.

    This step can hurt a person or ruin parts. Its instructions need sign-off by a human who has done it before relying on them. Stop and ask if anything differs from what you see.

    Parts in

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    Tools

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    Torque

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    Time

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    After

    12

    Source

    huggingface.co

14. Policy
    14

    Record a dataset

    `hf auth login --token ${HUGGINGFACE_TOKEN} --add-to-git-credential`, then set `remote_ip`, `repo_id`, `port` and `task` in `examples/lekiwi/record.py` and run `python examples/lekiwi/record.py` with lekiwi_host running on the Pi. Upstream suggests at least 50 episodes, 10 per object location, with fixed cameras.

    CHECKThe dataset is at `~/.cache/huggingface/lerobot/<repo-id>` and on the Hub, and `python examples/lekiwi/replay.py` replays episode 0 on the robot.

    Parts in

    —

    Tools

    Hugging Face account with a write token

    Torque

    —

    Time

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    After

    13

    Source

    huggingface.co

15. 15

    Train a policy

    `lerobot-train --dataset.repo_id=${HF_USER}/<lekiwi dataset> --policy.type=act --output_dir=outputs/train/act_lekiwi --job_name=act_lekiwi --policy.device=cuda --policy.repo_id=${HF_USER}/my_lekiwi_policy` (or `--policy.path=lerobot/smolvla_base` to fine-tune SmolVLA). Add `--job.target=a10g-small` to train on Hugging Face Jobs.

    CHECKCheckpoints appear under outputs/train/act_lekiwi/checkpoints and the model is pushed to the Hub.

    Parts in

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    Tools

    CUDA GPU, Apple silicon, Colab or HF Jobs

    Torque

    —

    Time

    —

    After

    14

    Source

    huggingface.co

16. 16

    Run the policy on LeKiwi

    Safety · human-verified required

    With lekiwi_host running on the Pi, set `remote_ip`, `port` and the model id in `examples/lekiwi/evaluate.py` and run `python examples/lekiwi/evaluate.py`. Stay within reach of the power bank or battery lead: the policy also drives the wheels.

    CHECKThe robot attempts the recorded task from a start pose seen in training and stops at the end of the evaluation episodes.

    This step can hurt a person or ruin parts. Its instructions need sign-off by a human who has done it before relying on them. Stop and ask if anything differs from what you see.

    Parts in

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    Tools

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    Torque

    —

    Time

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    After

    15

    Source

    huggingface.co

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