Legolas (open-source biped)

Legolas is a mini bipedal robot by David Doan, inspired by Agility Robotics' Cassie, intended as an open platform for learning and applying reinforcement learning to legged locomotion. The hardware repository contains the SolidWorks CAD (V1/V2/V3 iterations, including a redundant right-leg mirror and a test bench) plus a complete set of printable STLs for V2, and MuJoCo XML models for simulation. Actuation is low-cost hobby servos (8x 40 kg-cm and 2x 80 kg-cm) driven by a PCA9685 board from a Raspberry Pi 4, with an MPU6050 IMU and ADS1115 ADC, M4 connecting-rod / ball-joint linkages, and thrust bearings. The BOM is provided as linked Amazon parts rather than a costed table, and step-by-step assembly instructions are noted as a future addition. The control code lives in a separate Legolas_Controller repository.

What you get

• A standardized, machine-readable robot schema derived from the source repo.
• A limited/simplified source 3D asset is available from Mujoco xml/Working Mk 5 - Old model - Demo only/CMU Mk 5.xml.
• Source-backed bill-of-materials evidence is linked with per-part provenance where available. Prices marked estimated are not yet verified against a vendor.
• A transparent reproducibility score so buildability is a sortable, first-class property.
• Cross-links to the source repo, datasets, models, and forks.

Source

Canonical source: daviddoo02/Legolas-an-open-source-biped. Original files stay intact and separately licensed under MIT; Motari adds a separate, adjacent metadata layer.