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.
Category: Mobile Robots
| Item | Qty | Unit Cost (USD) | Total (USD) | Notes | |------|-----|-----------------|-------------|-------| | T-Motor Antigravity 4004 300KV brushless motor | 12 | $90 | $1,080 | One per actuator module — [T-Motor Store](https://store.tmotor.com/product/antigravity-4004-kv300.html) | | Broadcom AEDT-9810-Z00 encoder + PWB codewheel #104768 | 12 | $35 | $420 | Joint position — [Mouser](https://www.mouser.com/c/?q=AEDT-9810) / [DigiKey](https://www.digikey.com/en/products/result?keywords=AEDT-9810-Z00) | | Master Board v2 (custom STM32 + EtherCAT/SPI) | 1 | $300 | $300 | Open-hardware PCB — [ODRI repo](https://github.com/open-dynamic-robot-initiative/master-board) | | Micro Driver Board v2 (dual brushless FOC, BLMC µDriver) | 6 | $250 | $1,500 | One per pair of motors — [ODRI repo](https://github.com/open-dynamic-robot-initiative/micro-driver-board) | | Lord Microstrain 3DM-CX5-25 IMU (±900°/s, ±20 g) | 1 | $1,500 | $1,500 | Body IMU — [Microstrain shop](https://www.microstrain.com/inertial-sensors/3dm-cx5-25) | | Timing Belt AT3 GEN III — 150mm × 4mm (stage 1) | 12 | $5 | $60 | [Beltingonline](https://www.beltingonline.com/) / [Reiff](https://www.reiff-group.com/) | | Timing Belt AT3 GEN III — 201mm × 6mm (stage 2) | 12 | $6 | $72 | Same suppliers | | Aluminum motor pulley AT3 T10 (machined) | 12 | $25 | $300 | Custom-machined per drawings | | Aluminum center pulley AT3 T10 (machined) | 12 | $25 | $300 | Custom-machined per drawings | | Bearing EZO 61705-2RS VA (32×25×4) — output shaft | 24 | $8 | $192 | 2 per actuator — [EZO USA](https://www.ezousa.com/) | | Bearing EZO MR84 VA (8×4×2) — motor/center shaft | 36 | $4 | $144 | 3 per actuator | | Bearing EZO 683 2Z VA (7×3×3) — belt tensioner | 24 | $4 | $96 | 2 per actuator | | Bearing ET2520 2Z VA (25×20×4) — hip AA | 4 | $10 | $40 | Body | | 4mm stainless steel motor shaft (precision-cut) | 12 | $5 | $60 | [Amazon search](https://www.amazon.com/s?k=4mm+stainless+steel+precision+rod) | | 24V 6S LiPo battery (5000 mAh) | 2 | $80 | $160 | One pack + spare — [Amazon search](https://www.amazon.com/s?k=6S+5000mAh+LiPo+battery) | | Helicoil M3×4.5mm thread inserts (50-pack) | 1 | $25 | $25 | Body Helicoils + actuator output (≥56 needed) — [Amazon search](https://www.amazon.com/s?k=Helicoil+M3+thread+insert) | | M2.5 / M3 / M4 socket-head + flat-head screw assortment (stainless) | 1 | $30 | $30 | Project-specific — [Amazon search](https://www.amazon.com/s?k=M2.5+M3+M4+screw+assortment+stainless) | | Vicon motion-capture markers, 9.5 mm (set of 16) | 1 | $50 | $50 | Optional, for mocap labs — [Vicon shop](https://www.vicon.com/hardware/accessories/) | | Ethernet patch cable + EtherCAT-capable USB-Ethernet | 1 | $30 | $30 | Realtime link to host PC — [Amazon search](https://www.amazon.com/s?k=USB+Ethernet+adapter+gigabit) | | Mini-PC / NUC running PREEMPT_RT Linux | 1 | $400 | $400 | Realtime control host — [Amazon search](https://www.amazon.com/s?k=Intel+NUC+i5+barebone) | | 16 AWG silicone hookup wire (red/black) | 1 | $20 | $20 | Battery → master board — [Amazon search](https://www.amazon.com/s?k=16+AWG+silicone+wire+10ft) | | XT60 connector pairs | 6 | $2 | $12 | [Amazon search](https://www.amazon.com/s?k=XT60+connector+kit) | | 3D-printer filament (PA-CF or PETG-CF, ~3 kg) | 3 | $50 | $150 | All printed body/leg parts — [Amazon search](https://www.amazon.com/s?k=PA-CF+filament+1kg) | **Estimated total: $6,500–$8,000 USD** (kits from PAL Robotics ≈ €15,000+ assembled). Source: https://github.com/open-dynamic-robot-initiative/open_robot_actuator_hardware (`mechanics/quadruped_robot_12dof_v1/` and `mechanics/actuator_module_v1/`).