Solo12 is an open-source 12-DOF quadruped robot from the Open Dynamic Robot Initiative (ODRI), a collaboration between MIT, LAAS-CNRS, NYU, and MPI-IS to provide the legged-locomotion research community with an affordable, reproducible platform for dynamic control research.

The robot has four legs, each with three degrees of freedom (hip abduction/adduction, hip flexion/extension, and knee), actuated by ODRI's open-source brushless direct-drive actuator modules. Direct-drive transmissions give the robot high-bandwidth torque control and transparent dynamics — critical for whole-body MPC, reinforcement learning, and contact-rich locomotion experiments that are difficult or impossible on geared quadrupeds.

Solo12 has been used in dozens of published locomotion papers studying bounding gaits, stair climbing, reactive balance control, sim-to-real reinforcement learning, and model-predictive control. The full hardware and software stack — actuator PCBs, mechanical CAD, master board firmware, real-time control interface, and Pinocchio-based dynamics — is published under BSD-3-Clause, making Solo12 one of the most accessible research-grade quadrupeds available.

This program provides cloud-side locomotion commands (stand, sit, directional walking, trot, emergency stop) that relay to the onboard controller over WebSocket. The hardware requirement is a Raspberry Pi 4 acting as the high-level controller; the real-time low-level control loop runs on the master board over EtherCAT/SPI to the 12 actuator modules.

Credit to the Open Dynamic Robot Initiative consortium (LAAS-CNRS, MPI-IS, NYU, MIT) — upstream repository at https://github.com/open-dynamic-robot-initiative/open_robot_actuator_hardware under BSD-3-Clause.

Build Guide

Step-by-step assembly instructions for the Solo12 quadruped: Solo12 hardware README