[![Join our Discord](https://img.shields.io/badge/Join%20our%20Discord-5865F2?style=for-the-badge&logo=discord&logoColor=white)](https://discord.com/invite/pfWrJeJRh6) # XGO-Duck **English** · [简体中文](README_CN.md) **Build a robot duck. Explore how it moves. Make it your own.** A 3D-printable biped robot built around Arduino UNO Q and 15 serial servos. [Assembly guide](Assembly_Guide.pdf) · [Bill of materials](BOM.md) · [Runtime](https://github.com/LuwuDynamics/xgoduck_runtime_arduino) · [Training](https://github.com/LuwuDynamics/xgoduck_rl) A duck-shaped biped robot performing a somersault in a looping animation *A clean somersault · CyberBionic Maker*
## Meet XGO-Duck XGO-Duck is a duck-shaped biped robot adapted by **Luwu Dynamics** from Pollen Robotics' **Microduck**. It combines a printable structure, fifteen Feetech 1910 servos, an Arduino UNO Q, and a custom expansion board with an IMU and servo interfaces. This repository is the hardware starting point: **print the parts, prepare the electronics, and assemble the robot**. Companion repositories provide the onboard runtime and reinforcement-learning tools, connecting a physical build with motion experiments. | Build | Run | Experiment | | --- | --- | --- | | Print the body, legs, neck, head and soft parts. Assemble with the illustrated guide. | Configure and calibrate the robot through the companion runtime's browser interface. | Study the simulation, train policies and explore your own motions. | | [Hardware files](#hardware-files) | [Onboard runtime](https://github.com/LuwuDynamics/xgoduck_runtime_arduino) | [RL tools](https://github.com/LuwuDynamics/xgoduck_rl) | ## A closer look XGO-Duck standing on a workbench, with a white printed body, yellow beak and feet, and exposed leg joints *XGO-Duck prototype — printed parts, articulated legs, and a movable head and beak.*
Front view of XGO-Duck with its beak open
A movable head and beak
Four neck/head joints and a separate mouth servo.		 Rear prototype view showing the blue expansion board and servo wiring
Electronics you can inspect
Rear-mounted controller stack and accessible wiring.
The photos show project prototypes. Follow the assembly guide and matching board files for your build revision. ## Hardware at a glance | Subsystem | What it uses | Role | | --- | --- | --- | | Controller | Arduino UNO Q | Linux host for policy inference and web UI; STM32 MCU for servo and sensor communication | | Actuation | 15 Feetech 1910 serial servos | 10 leg joints, 4 neck/head joints, and 1 mouth joint | | Expansion board | Luwu UNO Q expansion board | Power distribution, servo connections and IMU integration | | Motion sensing | QMI8658A 6-axis IMU | Acceleration and angular-velocity feedback | | Structure | STL parts | Body, leg, neck and head components | | Soft parts | TPU-designated STL files | Foot soles and mouth parts | The motion policy outputs targets for **14 joints**; the mouth servo is controlled separately. Component details and purchasing checks are collected in the [BOM notes](docs/BOM.md). ### How the system connects ```mermaid flowchart TD UI[Browser: setup, calibration and control] <--> HOST[UNO Q Linux: ONNX policy and web UI] RL[Training computer: simulation and RL] -->|Export ONNX policy| HOST HOST <-->|Arduino Bridge| MCU[UNO Q STM32: servo and IMU loop] MCU <-->|Serial bus| SERVOS[15 Feetech 1910 servos] IMU[QMI8658A IMU] -->|Sensor feedback| MCU BOARD[Custom expansion board] --- SERVOS BOARD --- IMU ``` This is a functional overview; use the board design and assembly documentation for electrical connections. ## Start your build > **Hardware correction — 2026-10-02:** The old ArduinoUnoQ PCB reverses GND and SIGNAL on **U3, U4 and U5**. Owners of previously manufactured boards should disconnect power and follow the [old-board wiring instructions](PCBA/README.md#english-notice-for-previously-manufactured-boards). Pin 2 power is unchanged. Schematic and PCB sources are updated. ### 1. Prepare parts and electronics Open the [bill of materials](BOM.md) for the robot purchasing list, supplier links and battery requirements, and [PCBA/](PCBA/) for the expansion-board files. The robot BOM and PCB manufacturing BOM serve different purposes: a finished expansion board already includes its board-level components. | Part | Quantity | | --- | ---: | | Arduino UNO Q (2 GB / 4 GB) | 1 | | [Robot expansion board — Luwu Dynamics Store](https://shop.xgorobot.com/products/robot-driver-board?variant=67594424713467) | 1 | | Feetech 1910 servo | 15 | | AMP 3-pin servo cable | 15 | | Battery pack, listed as “18650 battery 8.4V” | 1 | | 8.4 V Li-ion battery charger with 5.5 × 2.1 mm DC barrel plug (DC5521) | 1 | | M2 × 6 countersunk, flat-end self-tapping screw | 200 | | M2.3 × 8 flat-top round-head, flat-end self-tapping screw | 6 | | M3 × 16 round-head machine screw | 4 | | 10 × 15 × 3 mm bearing | 2 | | 16 × 22 × 4 mm bearing | 11 | Quantities reproduce the purchasing list, including screw quantities. Confirm the pack, charger, connector polarity and power requirements using the [component notes](docs/BOM.md) before sourcing or powering the build. **Identify the three fasteners before ordering.** Items 7 and 8 are self-tapping screws with flat ends. Items 8 and 9 share the same rounded side profile; item 8 has a flat top, while item 9 has the gently domed top shown in the photo below and a machine thread. The following shape guide is illustrative. See the [product photo and size references](BOM.md#fastener-identification) in the BOM. Shape guide for the M2 by 6 countersunk flat-end self-tapping screw, M2.3 by 8 flat-top round-head flat-end self-tapping screw, and M3 by 16 domed round-head machine screw Reference photo of the intended shallow, gently domed round screw head for item 9 only *Item 9 has the domed top shown here. Item 8 has the same rounded sides but a flat top. The photo is a head-style reference, not a size or thread specification.* ### 2. Print the structure Download the models from [structure/](structure/). The filenames carry useful assembly information: | Filename pattern | Meaning | Example | | --- | --- | --- | | `2x_` | Print two copies | `2x_shank.stl` | | `left_` / `right_` | Separate left and right parts | `left_foot.stl`, `right_foot.stl` | | `tpu` | Flexible part | `2x_foot_bottom_tpu.stl`, `mouth_up_tpu.stl` | Use the [print inventory](docs/PRINTING.md) to track parts. Test a servo mount and bearing fit before printing the full set; a complete validated print profile is still to be documented. ### 3. Configure servos and assemble Prepare each servo's ID and center position using the [runtime setup instructions](https://github.com/LuwuDynamics/xgoduck_runtime_arduino#first-time-servo-setup), then follow [Assembly_Guide.pdf](Assembly_Guide.pdf). | Assembly reference | Focus | | --- | --- | | Page 1 | Servo ID placement | | Pages 2–5 | Shaft preparation, initial structure and cable routing | | Pages 6–15 | Legs, feet and soles | | Pages 16–23 | Head and neck mechanisms | | Pages 24–25 | Final assembly | The [build guide](docs/BUILD_GUIDE.md) adds preparation and inspection checkpoints. Configure one servo at a time, label its ID, and leave cable clearance through each joint's movement. ### 4. Calibrate and bring it to life Install the [onboard runtime](https://github.com/LuwuDynamics/xgoduck_runtime_arduino), verify servo and IMU feedback, and complete calibration with the robot supported. Start with the default pose before motion trials. The runtime includes **walk, get-up and pick policies**, plus separate mouth control. Their behavior depends on the assembled hardware, calibration and test conditions. Using the bundled policies does not require training a new model. ## Hardware files | Path | Contents | | --- | --- | | [Assembly_Guide.pdf](Assembly_Guide.pdf) | 25-page illustrated assembly reference | | [BOM.md](BOM.md) | Whole-robot purchasing list, supplier links and battery reference image | | [structure/](structure/) | Printable STL models | | [PCBA/ArduinoUnoQ.SchDoc](PCBA/ArduinoUnoQ.SchDoc) | Altium schematic source | | [PCBA/ArduinoUnoQ.PcbDoc](PCBA/ArduinoUnoQ.PcbDoc) | Altium PCB source | | [PCBA/ArduinoUnoQ.pdf](PCBA/ArduinoUnoQ.pdf) | Board layout and dimension drawing | | [PCBA/ArduinoUnoQ.DWG](PCBA/ArduinoUnoQ.DWG) · [STEP model](PCBA/ArduinoUnoQ.step) | Board outline and mechanical integration model | | [PCBA/BOM.xlsx](PCBA/BOM.xlsx) · [Pick-and-place data](PCBA/Pick%20Place%20for%20ArduinoUnoQ.csv) | Expansion-board assembly materials and placement coordinates | | [docs/](docs/) | Build, printing, BOM and troubleshooting notes | ## From hardware to your own behavior | Repository | Purpose | | --- | --- | | **[xgoduck_hardware](https://github.com/LuwuDynamics/xgoduck_hardware)** | Mechanical parts, electronics, BOM and assembly | | **[xgoduck_runtime_arduino](https://github.com/LuwuDynamics/xgoduck_runtime_arduino)** | UNO Q firmware, policy execution, browser setup and control | | **[xgoduck_rl](https://github.com/LuwuDynamics/xgoduck_rl)** | Simulation, reinforcement-learning training and policy export | Keep the hardware, runtime and policy revisions together in your build record. This makes it easier to reproduce a working configuration and diagnose changes. ## Origins and contributions XGO-Duck builds on [Microduck](https://github.com/pollen-robotics/microduck) and [microduck_rl](https://github.com/pollen-robotics/microduck_rl) by **Pollen Robotics**. The duck form, 15-servo arrangement and policy joint order originate in that work. Luwu Dynamics' adaptation focuses on **Arduino UNO Q, Feetech 1910 servos, the custom expansion board, and the matching software/model integration**. See [origins and adaptations](UPSTREAM.md). Build reports, tested print settings, clearer assembly photos and reproducible fixes are welcome. Read [CONTRIBUTING.md](CONTRIBUTING.md) or [open an issue](https://github.com/LuwuDynamics/xgoduck_hardware/issues). For reuse terms, consult [LICENSING.md](LICENSING.md) and the applicable file-level notices. Contact: **hello@xgorobot.com**.