Co-designing muscle and scaffold increased biorobot motion elevenfold
ETH Zurich researchers modeled and optimized skeletal muscle tissue and a microgrooved hydrogel scaffold as one system. The centimeter-scale bioactuators increased range of motion by as much as elevenfold compared with earlier designs using similar muscle volume. In the Nature Communications study, the actuators powered robots that jumped, swam, walked and gripped; these are laboratory prototypes, not ready medical or commercial products.
Science··Midday
Treating muscle and scaffold as one system
Instead of adding living muscle to a scaffold fixed in advance, the study treats muscle tissue and support structure as parts of the same design problem. Researchers modeled both in a soft-body simulation and searched for shapes that maximize range of motion using an evolutionary algorithm and targeted parameter sweeps. In the resulting devices, skeletal muscle forms a continuous interface with a microgrooved hydrogel scaffold. That connection supports force transmission and allows the centimeter-scale actuator to make large, rapid deformations.[1]
Up to elevenfold motion
The co-optimized actuators increased range of motion by as much as elevenfold relative to previous designs with similar muscle volume. The team demonstrated the approach in several robotic arrangements that jump, swim, walk and grip, and also assembled multiple actuators into larger systems. Supplementary footage shows those movements while electrical stimulation supplied 3.3 to 5 volts across each centimeter at 1 to 3 beats per second. The comparison is bounded to specific laboratory designs rather than every form of biohybrid actuator.[1]
The stage demonstrated by the prototype
The findings show that calculating muscle placement and scaffold geometry together can improve motion generation. Experiments used small devices fabricated in the laboratory; they did not test long-term durability, mass production, environmental resilience or use inside a living body. The contribution is a reusable design method linking simulation to fabrication instead of manually choosing a shape for each task. The result does not mean an elevenfold increase in the robots' overall capability: the measured quantity was range of motion.[1]
