CocoNuts
Based on published sources · Not tested by us ·
Overview
Humanoid design and one-leg benchmark exploring low leg inertia through belts and parallel linkages; the maintainer has put the project on hold. [S001]
CocoNuts explores reducing leg inertia by placing actuator mass closer to the body. Timing belts relocate knee and ankle-pitch actuation, and a four-bar parallel linkage transmits ankle motion. The maintainer describes a built one-leg benchmark alongside the broader humanoid CAD design, and reports running example trajectories with ankle-only, knee-only and combined knee-and-ankle actuation. That evidence should not be read as a demonstrated complete walking humanoid. [S001]
Specifications
| Detail | Description |
|---|---|
| Type | Humanoid CAD concept with a physically built one-leg benchmark described by the maintainer. Reported by source [S001] · Checked 2026-09-30 |
| Intended users | Researchers studying leg mechanisms and motor test workflows Editorial assessment [S001] · Checked 2026-09-30 |
| Assembly | Timing belts move knee and ankle-pitch actuation closer to the hip; ankle motion uses a four-bar parallel linkage. Full assembly reproduction has not been established. Reported by source [S001] · Checked 2026-09-30 |
| Calibration | README describes motor IDs, CAN-filter configuration and zero positions for the one-leg setup. No motor settings were changed or verified here. Reported by source [S001] · Checked 2026-09-30 |
| Operating system | Not known |
| Computer needed | Not known |
3D preview
Preview not available yet. A model has not yet been prepared and approved for display on this page. This does not mean the project lacks CAD files; see Source files and licenses for the reviewed source availability.
Assembly and use
The negative results are part of the value
The README reports two difficulties in the prototype: the RMD-X6 actuators were oversized for the tested leg scale, and the belt/linkage mechanism introduced compliance and play that made precise control difficult. The maintainer concludes that the architecture needs a substantial change and explicitly places the project on hold as a technical reference. These are the author's findings, not measurements repeated by this publication. [S001]
For a researcher comparing transmission arrangements, the preserved mechanism and test workflow remain useful. For someone seeking a build-ready humanoid, the unresolved architecture and limited bill of materials are material constraints. The hardware BOM lists actuator quantities only: four RMD X6 1:6, four TD 30-40 and four TD 40-52. It is not a complete fabrication, electronics or delivered-cost estimate. [S001] [S005]
Distinguish the visualizer from motor execution
The software operates RMD-X6 motors through a CANalyst-II interface. The project declares Python 3.12 or newer and dependencies including python-can, placo, matplotlib and PyQt5; the README uses uv for setup. The author explicitly says this Python implementation is intended for setup and testing rather than real-time control. [S001] [S006]
The one-leg benchmark normally visualizes trajectories in Meshcat. A plot option shows the trajectories, while the separate --send option sends the benchmark to physical hardware. Motor IDs, zero positions and CAN settings are described in the README, but none were applied in this review. Inspecting the default visualizer is not a physical validation of the leg or its control configuration. [S001]
Hardware and software have different licenses
The hardware and robot-description folder is licensed under CERN-OHL-S-2.0; control software is Apache-2.0. The README also links a versioned Onshape design. These declarations do not make purchased motor electronics, actuator firmware or unrelated third-party assets part of a fully open manufacturing bundle. No images have been republished and no hardware build, timing test or motion benchmark was performed here. [S001] [S003] [S007] [S008]
Cost
No current, complete configuration-specific build cost has been established for this profile.
Source files and licenses
Available project sources support research coverage; complete build and commercial qualification remain separate.
| Layer | Availability / license |
|---|---|
| mechanical design | available · CERN-OHL-S-2.0 Hardware and robot-description folder; README also links versioned Onshape CAD. Purchased actuator rights remain separate. [S001] [S003] [S007] |
| electronics | not found · License not fully assessed No complete independently licensed motor-drive electronics or firmware manufacturing set established in the inspected archive; purchased actuators/interface are used. [S001] [S004] [S005] |
| firmware | not found · License not fully assessed No complete independently licensed motor-drive electronics or firmware manufacturing set established in the inspected archive; purchased actuators/interface are used. [S001] [S004] [S005] |
| software | available · Apache-2.0 Control software; independent dependencies retain their licenses. [S003] [S008] |
| documentation | available · License not fully assessed Public repository instructions; root license assigns hardware and software folders, without separately resolving every documentation/media asset. [S001] [S003] |
Selected workflow uses specified motor trajectories, not a learned policy or dataset.
References
Links identify the documentation and revisions used in this profile. Access dates record when each source was retrieved.
- S001 · MarcDcls / project contributors
Upstream project overview
Accessed 2026-09-30 · README.mdSource notes
Source text inspected for the cited scoped claims; see profile claim notes.
- S002 · MarcDcls / project contributors
Repository revision and release metadata
Accessed 2026-09-30 · 960e6409db5d4683d49b85c8fdd6e424893250e4Source notes
Source text inspected for the cited scoped claims; see profile claim notes.
- S003 · MarcDcls / project contributors
Repository license
Accessed 2026-09-30 · LICENSESource notes
Source text inspected for the cited scoped claims; see profile claim notes.
- S004 · MarcDcls / project contributors
Pinned repository artifact inventory
Accessed 2026-09-30 · 960e6409db5d4683d49b85c8fdd6e424893250e4 archive file inventorySource notes
Source text inspected for the cited scoped claims; see profile claim notes.
- S005 · MarcDcls / project contributors
Pinned CocoNuts: hardware/BOM.md
Accessed 2026-09-30 · 960e6409db5d4683d49b85c8fdd6e424893250e4 / hardware/BOM.mdSource notes
Source text inspected for the cited scoped claims; see profile claim notes.
- S006 · MarcDcls / project contributors
Pinned CocoNuts: pyproject.toml
Accessed 2026-09-30 · 960e6409db5d4683d49b85c8fdd6e424893250e4 / pyproject.tomlSource notes
Source text inspected for the cited scoped claims; see profile claim notes.
- S007 · MarcDcls / project contributors
Pinned CocoNuts: hardware/LICENSE
Accessed 2026-09-30 · 960e6409db5d4683d49b85c8fdd6e424893250e4 / hardware/LICENSESource notes
Source text inspected for the cited scoped claims; see profile claim notes.
- S008 · MarcDcls / project contributors
Pinned CocoNuts: software/LICENSE
Accessed 2026-09-30 · 960e6409db5d4683d49b85c8fdd6e424893250e4 / software/LICENSESource notes
Source text inspected for the cited scoped claims; see profile claim notes.
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