Musbric builds reconfigurable muscle-powered robots with legos
MUSBRIC: LEGO-Compatible Pneumatic Muscle Bricks for Reconfigurable Musculoskeletal Robots
Robotics
Summary
Building robots with muscles that move like real limbs usually requires a lot of custom parts that are hard to change. The authors created MUSBRIC, a system using special artificial muscles that snap onto LEGO pieces, letting people quickly build and test different robot shapes. They also made computer simulations that match how these muscles behave in real life, so users can experiment without making new parts each time. The system includes examples like an arm joint, a robotic hand, and walking robot legs that show it can handle lots of different robot designs.
What this means in practice
- •For robotics engineers: Create and test new robot limb designs quickly by snapping compliant muscle modules onto standard building blocks without custom fabrication.
- •For robotics educators: Demonstrate musculoskeletal robot concepts and control using LEGO-compatible muscle modules and matched simulations for hands-on learning.
Authors
Qiyao Wang, Yinglei Zhu, Liang Zhou, Wenzhe Gong, Xin-Jun Liu, Huichan Zhao
Abstract
Musculoskeletal robots combine compliant actuators with articulated skeletons, but exploring alternative configurations often requires repeated fabrication. We present MUSBRIC, a modular hardware platform and accompanying MuJoCo-based simulator for reconfigurable musculoskeletal robots. LEGO-compatible endcaps turn fiber-reinforced extensile pneumatic artificial muscles into reusable, plug-and-play muscle bricks that connect directly to standard LEGO components. Experimentally identified actuator behavior supports corresponding musculoskeletal simulations. An elbow-joint prototype validates load-dependent flexion and extension, showing that pulley-guided routing enables reversible motion and a mechanical stop stabilizes the straight posture. A robotic hand demonstrates compliant grasping and multi-joint construction. Matched hardware and simulation sweeps across 15 leg configurations demonstrate systematic exploration of attachment geometry, while a quadruped assembled from four legs demonstrates walking. Together, these demonstrations span mechanism analysis, configuration exploration, and functional robot construction within a single reconfigurable system. The hardware designs and simulation code will be released as open source soon to facilitate reproduction and further development.