In the field of biohybrid robotics, we have seen many recent examples. The core objective is to integrate biological muscle tissue with soft engineered materials to create more adaptive and functional machines. Traditionally, however, movement has been constrained because muscles were anchored to rigid structures—a weak point where the connections often proved fragile. To overcome this, researchers approached the design by treating the muscle and its support structure as a single, unified system.

Scientists in Switzerland have developed small robots capable of jumping, swimming, walking, and even grasping objects by using living, lab-grown muscle tissue instead of conventional electric motors. Although only footage of them swimming has been released so far, this innovation is well worth noting.

Developed by researchers at ETH Zurich and presented in a study published in the scientific journal *Nature Communications*, these machines are built using mouse muscle cells cultured on a flexible artificial framework made of a material known as a hydrogel. When subjected to electrical stimuli, the muscle cells contract—just as they would in an animal—causing the artificial structure to deform and, in turn, generating movement in the robot.

To build larger robots, scientists will need to develop systems capable of transporting oxygen and nutrients deep into their tissues, much like a circulatory system. Despite these limitations, this research opens up a fascinating possibility for engineering: creating machines that directly harness the properties of living organisms. Rather than simply mimicking animal movements using motors, engineers are beginning to incorporate actual biological muscles into robotic mechanisms.

These scientists have developed an evolutionary artificial intelligence that reorganizes elements of contractile tissue and passive hydrogel supports to maximize movement performance. Once the structure has been optimized—following thousands of iterations—it is precisely fabricated using light-based volumetric printing. This process creates essential microchannels that allow muscle fibers to grow across the framework. Myoblasts are then introduced; after a few weeks of maturation, they fuse and align optimally along the pre-established guides.

Finally, by applying controlled electrical impulses to the mature bio-muscle via inserted electrodes, the muscle tissue contracts, causing the entire structure to bend. When the muscle relaxes, the elastic energy stored in the soft support allows the structure to return to its original shape, effectively propelling the device through an aqueous environment. This new approach more than triples the range of motion compared to the most similar previous designs.