Auto-assembled, not yet reviewed

Open Duck Mini

Open Duck Mini v2, a roughly 42 cm BDX-style miniature biped.

Reproducibility63/100Partial source coverage, unverifiedCADBOMWIREFWBUILDLICREPHow it is computed
Open Duck Mini open-source 16-DoF biped robot, 3D render from robot.urdf
main assembly 3D · robot.urdf

About Open Duck Mini

Open Duck Mini v2 is a roughly 42 cm miniature BDX-style biped. The upstream repository links a BOM sheet, print guide, assembly guide, wiring and electronics notes, a MuJoCo and URDF robot description and the runtime policy code. BOM prices and vendor links are the ones in the upstream sheet.

Licenses

Hardware
Apache-2.0
Software
Not published
Docs
Not published

Degrees of freedom

16 DoF legs 10antennas 2headNeck 4

Breakdown source

Bipedsource

How to build Open Duck Mini

5 steps

Steps marked Motari summary condense the linked source; follow the source for exact instructions. Upstream step marks a step taken from the linked guide.

  1. Print the parts

    Use the pinned STL set. The source print guide specifies standard PLA at 15% infill, except foot_bottom_tpu.stl in TPU at 40% infill, and lists the printed part quantities.

    Upstream stepgithub.com/apirrone/Open_Duck_Mini/blob/b23317a485b3cec7d841...

  2. Configure each motor

    Install the runtime tools and run configure_motor.py for each source-listed motor ID before building, then align the horn at the zero position.

    Upstream stepgithub.com/apirrone/Open_Duck_Mini/blob/b23317a485b3cec7d841...

  3. Assemble trunk, feet and legs

    Follow the source assembly guide: install bearings and M3 inserts, assemble trunk_bottom/trunk_top, build TPU/PLA feet, route motor cables and assemble shins, thighs and hips.

    Upstream stepgithub.com/apirrone/Open_Duck_Mini/blob/b23317a485b3cec7d841...

  4. Install head, IMU and electronics

    Mount the neck/head mechanism, place the IMU according to the assembly note, then reconcile the source wiring/electronics schematic and linked BOM sheet before powering the robot.

    Motari summarygithub.com/apirrone/Open_Duck_Mini/blob/v2/docs/assembly_gui...

  5. Deploy runtime and walking policy

    Flash the Raspberry Pi Zero 2W, install the runtime, check the IMU and motors, find the joint offsets for duck_config.json, then run the walking policy.

    Upstream stepgithub.com/apirrone/Open_Duck_Mini_Runtime/blob/376de65435c9...
Print timenot published
Assembly timenot published

Wiring, power and firmware are safety-relevant and shown for reference only. Check them against the source before building.

Open Duck Mini bill of materials

22 rows

Cost to build

€398.10EURsource total

In the source currency, as read on 2026-09-30. Not converted, and not checked against current vendor prices: none of these is a Motari-verified checkout total.

Open Duck Mini parts, as the source lists them. Prices are the source's, not checked against vendors.

Open Duck Mini bill of materials
PartQtySpecSourceConfidence
18650 cellGet the beefiest 18650 cells you can find. I have 3000mAh with 30A discharge (under Power in the project's BOM)
2unit €5; sheet total €10; estimated lowest €10
vendor linked in the project's BOM€10From Open Duck Mini public BOM Google Sheet, linked in README.md
high
18650 cell holderUnder Power in the project's BOM
1€4.99 each
vendor linked in the project's BOM€4.99From Open Duck Mini public BOM Google Sheet, linked in README.md
high
2S BMSUnder Power in the project's BOM
1€8.4 each
vendor linked in the project's BOM€8.4From Open Duck Mini public BOM Google Sheet, linked in README.md
high
5V regulatorUnder Power in the project's BOM
1€4 each
vendor linked in the project's BOM€4From Open Duck Mini public BOM Google Sheet, linked in README.md
high
Small power switchNeed only one (under Power in the project's BOM)
1€4.49 each
vendor linked in the project's BOM€4.49From Open Duck Mini public BOM Google Sheet, linked in README.md
high
usb-c chargerneed only one (under Power in the project's BOM)
1€9.99 each
vendor linked in the project's BOM€9.99From Open Duck Mini public BOM Google Sheet, linked in README.md
high
2.1mm barrel jackNeed only two (under Power in the project's BOM)
2unit €1; sheet total €2; estimated lowest €2
vendor linked in the project's BOM€2From Open Duck Mini public BOM Google Sheet, linked in README.md
high
XT15? XT30 ?You only need one pair (male/female) but hard to buy just one. Estimated lowest price is the price of 1, unit price is the price of a bundle (under Power in the project's BOM)
1unit €8; sheet total €8; estimated lowest €0.5
vendor linked in the project's BOM€8 (lowest estimate €0.5)From Open Duck Mini public BOM Google Sheet, linked in README.md
high
IMU (BNO055)source sheet notes a cheaper AliExpress option that is not checked (under Servos, control and sensors in the project's BOM)
1unit €40; sheet total €40; estimated lowest unverified
vendor linked in the project's BOM€40 (a cheaper option is not checked)From Open Duck Mini public BOM Google Sheet, linked in README.md
high
Raspberry pi zero 2wUnder Servos, control and sensors in the project's BOM
1€26.08 each
vendor linked in the project's BOM€26.08From Open Duck Mini public BOM Google Sheet, linked in README.md
high
SD cardsource notes cheaper alternatives may exist (under Servos, control and sensors in the project's BOM)
1€10 each
vendor linked in the project's BOM€10From Open Duck Mini public BOM Google Sheet, linked in README.md
high
Servo control boardUnder Servos, control and sensors in the project's BOM
1€5 each
vendor linked in the project's BOM€5From Open Duck Mini public BOM Google Sheet, linked in README.md
high
Feetech 7.4v STS 3215Be sure to buy the 7.4v ones, also called 19kg.cm (under Servos, control and sensors in the project's BOM)
14unit €14; sheet total €196; estimated lowest €196
vendor linked in the project's BOM€196From Open Duck Mini public BOM Google Sheet, linked in README.md
high
Feet contact switches (SS-10)Under Servos, control and sensors in the project's BOM
4unit €1; sheet total €4; estimated lowest €4
vendor linked in the project's BOM€4From Open Duck Mini public BOM Google Sheet, linked in README.md
high
9g servosUnder Servos, control and sensors in the project's BOM
2unit €3.33; sheet total €6.66; estimated lowest €6.66
vendor linked in the project's BOM€6.66From Open Duck Mini public BOM Google Sheet, linked in README.md
high
3D printing M3 insertsUnder MISC in the project's BOM
1€5.99 each
vendor linked in the project's BOM€5.99From Open Duck Mini public BOM Google Sheet, linked in README.md
high
Standard PLAMaybe 500g of filament ("Free" if you already have PLA) (under MISC in the project's BOM)
1unit €20; sheet total €20; source says free only if already on hand
vendor not named€20; already-on-hand alternative not included in cost totalFrom Open Duck Mini public BOM Google Sheet, linked in README.md
high
TPU(for the feet, negligeable cost) (under MISC in the project's BOM)
1small TPU quantity for feet; source treats as negligible/on-hand material
vendor not namednot costed; negligible/on-hand source materialFrom Open Duck Mini public BOM Google Sheet, linked in README.md
high
Cable sheathUnder MISC in the project's BOM
1€9 each
vendor linked in the project's BOM€9From Open Duck Mini public BOM Google Sheet, linked in README.md
high
15cm micro usb to usb-c cableUnder MISC in the project's BOM
1€7 each
vendor linked in the project's BOM€7From Open Duck Mini public BOM Google Sheet, linked in README.md
high
50cm micro usb to usb c cableUnder MISC in the project's BOM
1€6 each
vendor linked in the project's BOM€6From Open Duck Mini public BOM Google Sheet, linked in README.md
high
BearingUnder MISC in the project's BOM
3unit €3.5; sheet total €10.5; estimated lowest €10.5
vendor linked in the project's BOM€10.5From Open Duck Mini public BOM Google Sheet, linked in README.md
high

Rows from the source's own parts list 10

README.md@b23317amarkdown

Source rowQtyPrice and vendorLine
Open Duck Mini v2 is about 42 cm tall and that the full BOM cost should be under $400.
1
apirrone/Open_Duck_Mini source docsunder $400
L11
Open Duck Mini priced BOM sheet
22 base rows
docs.google.com€398.1 base total; €331.1 estimated lowest
L71
README identifies Raspberry Pi Zero 2 W as the onboard runtime target.
1
apirrone/Open_Duck_Mini source docsno price listed
L91

docs/print_guide.md@b23317amarkdown

Source rowQtyPrice and vendorLine
locates STL files and gives PLA/TPU material and infill guidance.
1
apirrone/Open_Duck_Mini source docsno price listed
L3
lists the printed part quantities for feet, legs, trunk, head and body parts.
1
apirrone/Open_Duck_Mini source docsno price listed
L7

docs/configure_motors.md@b23317amarkdown

Source rowQtyPrice and vendorLine
uses the runtime repo and configure_motor.py command before assembly.
1
apirrone/Open_Duck_Mini source docsno price listed
L10
14 source motor IDs for leg, neck and head joints; headline DOF counts locomotion/body DOF
14
apirrone/Open_Duck_Mini source docsno price listed
L21

docs/assembly_guide.md@b23317amarkdown

Source rowQtyPrice and vendorLine
lists basic tools, wire, unspecified upstream M3 screws, and Loctite Threadlocker blue 243.
1
apirrone/Open_Duck_Mini source docsno price listed
L5
introduces electronics section and global electronics schematic reference.
1
apirrone/Open_Duck_Mini source docsno price listed
L175

1 more source files with parts rows are listed under Files.

Open Duck Mini source files

14 files

Files stay in the upstream repository under their own licenses; these links open them there. The 3D model on this page is Motari's conversion of the file named under Simulation.

Open Duck Mini in simulation

Robot description files a simulator or CAD tool can load, linked at the commit they were found.

The 3D specimen on this page is converted from mini_bdx/robots/open_duck_mini_v2/robot.urdf at b23317a.

Builds of Open Duck Mini

0 reviewed

No reviewed builds of Open Duck Mini yet.

A build log records the evidence (photos, a video, your repository), what the build cost, how long it took and what you changed. Each one is checked by Motari (until a maintainer claims this page) before it shows here, and reviewed builds count toward the reproducibility score.

Sources and provenance

Sources

Last push to apirrone/Open_Duck_Mini: 2026-01-31 (checked 2026-10-01)

Related links

How this page was made

Assembled from public sources on 2026-06-06, not yet reviewed by the maintainer. Each figure links to where it is stated; a value the sources do not state reads "not published". Last source review: source BOM sheet parsed with priced rows.

Original files stay intact and separately licensed; Motari adds only the summary on this page. Maintainer? Request a correction or removal.

Badge for the README

Maintain Open Duck Mini? Show its reproducibility score in the project's README. The badge links back to this page and updates with the score.

Badge: reproducibility 63/100

Markdown
[![Motari reproducibility score for Open Duck Mini](https://motari.io/api/v1/badge/open-duck-mini)](https://motari.io/r/open-duck-mini)
HTML
<a href="https://motari.io/r/open-duck-mini"><img src="https://motari.io/api/v1/badge/open-duck-mini" alt="Motari reproducibility score for Open Duck Mini" height="20"></a>

Not fully met yet: cad / mesh present (partial), bom evidence (partial), build instructions (partial). The score is read from the project's own sources, so publishing what is missing is what raises it. A score of 90 or more needs a reviewed build. How the score is computed