Solo 12 is a 2.5 kg research quadruped from the Open Dynamic Robot Initiative (Max Planck Institute and NYU) with 12 torque-controlled brushless actuators built from 3D-printed parts, belt reductions and custom driver boards. It is aimed at labs studying dynamic locomotion and is controlled from an external PC over a tether in the base version.
At a glance
| Parts cost | $7,100 (2022) project · The project estimates about 6,300 EUR in materials plus tax, before the IMU source ↗ |
|---|---|
| Difficulty | 5/5 Expert · Requires machined pulleys, custom PCBs, an expensive industrial IMU and real-time torque-control software. |
| Build time | Not stated |
| Tools needed | 3D printer, lathe and milling machine or wire EDM (timing belt pulleys), or a purchased encoder kit, soldering and electronics assembly, programmers for micro driver and master boards |
| Motors | 12 brushless actuator modules with timing belt reduction and optical encoders |
| Controller | Custom master board + BLMC micro driver boards, external PC |
| Sensors | Microstrain 3DM-CX5-25 IMU, joint encoders, optional foot contact switches |
| Published | ✓ Parts list✓ CAD/STL✓ Assembly guide✓ Wiring✓ Software✗ Video GitHub markdown pages with photos, STL/STEP files and step-by-step actuator instructions; Discourse forum |
| Activity | Last update 2022-09-06 · 1,481 GitHub stars · ODRI Discourse forum; hardware repo 1,481 stars, 258 forks |
| Kits | PAL Robotics sold assembled robots and kits (current availability unconfirmed) |
Licenses
| Design files | BSD-3-Clause source ↗ |
|---|---|
| Code | BSD-3-Clause (solo); BSD-2-Clause (master-board) source ↗ |
| Documentation | BSD-3-Clause (stated on each docs page in the hardware repo) source ↗ |
Builder notes
Practical points from the project's issue tracker, forum and docs, each linked to its source.
- The team says the robots are not optimized for cost and estimated about 6,300 EUR in materials, before adding the IMU, which is the single most expensive part. source ↗
- The master board firmware and wiring were designed around the Microstrain 3DM-CX5-25 IMU, so swapping in a cheaper IMU means adapting firmware and electronics. source ↗
- The timing belt pulleys use a modified AT3 tooth profile to cut backlash, so standard AT3 pulleys or tools will not work and the parts must be milled with a form cutter or cut by wire EDM. source ↗
- The actuator testing page was empty for a long time, and maintainers pointed builders to a master-board SDK example to test single modules instead. source ↗
- The encoder code wheel needs its aluminum collar parted off on a lathe, or the pre-modified motor shaft assembly can be ordered. source ↗
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- Stanford Pupper v2.1 (DJI motor version) · $1,600 (2023) · difficulty 4/5
- openDog V3 · $2,800–$3,400 (2023) · difficulty 4/5