mjbots quad

Based on published sources · Not tested by us · Sources checked 2026-10-01

Overview

Quadruped source collection with distinct A1 and A2 configurations, printable structural parts, C++ control and browser-based simulation; this review centers on the documented A1 operating configuration. [S001]

The mjbots quad repository contains structural designs, C++ control, simulation and configurations for several quadrupeds. This profile uses the documented A1 operation and maintenance path. Its configuration enumerates twelve joints across four legs; the separate A2 file changes geometry and other parameters, so the two should not be treated as interchangeable build specifications. [S001] [S005] [S006] [S007]

Official website · Source code

Specifications

Detail	Description
Type	Quadruped; selected A1 configuration has four legs and three controlled joints per leg. Reported by source [S005] [S006] · Checked 2026-10-01
Intended users	Experienced robotics developers able to reconcile hardware revisions and commission powerful actuators Editorial assessment [S001] · Checked 2026-10-01
Assembly	Printable chassis and leg artifacts are supplied alongside an external overall Fusion assembly link; the selected A1 guide covers operation and maintenance, not a complete manufacturing sequence. Reported by source [S001] [S005] [S009] · Checked 2026-10-01
Calibration	A1 leg re-zeroing uses fixtures after disassembly or belt skipping; belt tension must also be maintained. Reported by source [S005] · Checked 2026-10-01
Operating system	Host setup documented for Ubuntu 20.04/22.04; README adds a manual libtinfo5 compatibility step for Ubuntu 24.04. Reported by source [S001] · Checked 2026-10-01
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

Supplied structures and remaining build work

The archive has dated chassis and leg 3MF files, plus distinct chassis_a2 and leg_a2 directories. The README also links an overall Fusion assembly. File availability does not establish a complete matched manufacturing package: this review has not validated geometry, opened the external assembly or reconciled a full purchased-parts BOM. Current delivered build cost remains unknown. [S001] [S009]

The A1 guide begins with an assembled robot and a 4 Ah ONE+ battery. It explains browser/gamepad operation, belt tension and leg re-zeroing with fixtures. Its maintenance instructions identify a lower-leg qdd100 and three servos per leg. These are useful configuration details, but the operating guide is not a complete fabrication manual. [S005]

Host tools and physical calibration are different checks

The README documents Ubuntu 20.04/22.04 host setup and a libtinfo5 compatibility step for Ubuntu 24.04. The workspace selects Bazel 7.4.1 and brings in external repositories including rpi_bazel, mjlib and moteus. A browser-based simulator is documented, but neither the build nor simulation was executed in this review. [S001] [S008]

For physical A1 operation, the guide says startup-position detection catches only some invalid positions. It also requires re-zeroing after leg reassembly or belt skipping. These constraints matter when evaluating a used or modified robot; a successful host build would not establish calibration or safe physical operation. No actuator commands or locomotion tests were run here. [S005]

Source scope

The root license is Apache 2.0 and the README says most hardware and software files use that license. This does not replace individual notices or license checks for external dependencies and the separately linked assembly. The main archive's printable structural files and control source are established; a complete matched electronics, servo-firmware and manufacturing set is not established by this review. [S001] [S003] [S008] [S009]

The entry therefore supports source exploration and A1 configuration research while keeping A2 files, external components and unreproduced build claims distinct. [S005] [S006] [S007]

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 · Apache-2.0 README describes most files as Apache 2.0; independent dependencies and externally linked assembly require their own scope checks. [S001] [S003] [S009]
electronics	not found · License not fully assessed Complete selected electronics manufacturing/servo firmware package not established in this main archive; moteus is an external dependency and must be reviewed separately. [S008] [S009]
firmware	not found · License not fully assessed Complete selected electronics manufacturing/servo firmware package not established in this main archive; moteus is an external dependency and must be reviewed separately. [S008] [S009]
software	available · Apache-2.0 README describes most files as Apache 2.0; independent dependencies and externally linked assembly require their own scope checks. [S001] [S003] [S009]
documentation	available · Apache-2.0 README describes most files as Apache 2.0; independent dependencies and externally linked assembly require their own scope checks. [S001] [S003] [S009]

Selected control/simulation workflow is not based on distributed trained weights or datasets.

References

Links identify the documentation and revisions used in this profile. Access dates record when each source was retrieved.

S001 · mjbots / project contributors
Upstream project overview
Accessed 2026-10-01 · README.md
Source notes
Source text inspected for the cited scoped claims; see profile claim notes.
S002 · mjbots / project contributors
Repository revision and release metadata
Accessed 2026-10-01 · 8ce3bc4ae14e033fea38d88b6a1f46c349e871d6
Source notes
Source text inspected for the cited scoped claims; see profile claim notes.
S003 · mjbots / project contributors
Repository license
Accessed 2026-10-01 · LICENSE
Source notes
Source text inspected for the cited scoped claims; see profile claim notes.
S004 · mjbots / project contributors
Pinned repository artifact inventory
Accessed 2026-10-01 · 8ce3bc4ae14e033fea38d88b6a1f46c349e871d6 archive file inventory
Source notes
Source text inspected for the cited scoped claims; see profile claim notes.
S005 · mjbots / project contributors
Pinned docs/quada1/README.md
Accessed 2026-10-01 · docs/quada1/README.md
Source notes
Source text inspected for the cited scoped claims; see profile claim notes.
S006 · mjbots / project contributors
Pinned configs/quada1.cfg
Accessed 2026-10-01 · configs/quada1.cfg
Source notes
Source text inspected for the cited scoped claims; see profile claim notes.
S007 · mjbots / project contributors
Pinned configs/quada2.cfg
Accessed 2026-10-01 · configs/quada2.cfg
Source notes
Source text inspected for the cited scoped claims; see profile claim notes.
S008 · mjbots / project contributors
Pinned WORKSPACE
Accessed 2026-10-01 · WORKSPACE
Source notes
Source text inspected for the cited scoped claims; see profile claim notes.
S009 · mjbots / project contributors
Complete pinned filenames
Accessed 2026-10-01 · Complete archive inventory; not manufacturing validation
Source notes
Source text inspected for the cited scoped claims; see profile claim notes.

Research and review details

Source research only; no installation, physical build or performance test performed. No affiliate links added.

Profile edited 2026-10-01 · Sources checked 2026-10-01 · Next review target 2026-10-31

Revision: 8ce3bc4ae14e033fea38d88b6a1f46c349e871d6 (commit snapshot; no published stable release found). Combined hardware and software repository activity recorded 2026-06-17 [S002]

Correction guidance · Discussion is not enabled · Profile format 0.6.0-draft.1

Change history