3D printed living robots with self-training capabilities*

Biohybrid robotic systems are designed based on the combination of synthetic materials and biological entities aiming to acquire improved performance or properties that are difficult to mimic by their artificial counterparts. By integrating biological components (i.e. skeletal muscle cells) in robotic systems, it is possible to implement some of the most desirable capabilities from such living entities, including self-organization, self-healing or adaptability.

The exploitation of 3D printing as a versatile fabrication tool that has opened new possibilities for the creation of advanced bio-hybrid robots. In our study, we develop a skeletal muscle-based swimming biobot formed by a 3D-printed serpentine spring integrated into a 3D cell laden scaffold. The spring skeleton provides dynamic mechanical self-stimulation during the cell differentiation process, promoting a greater maturation and alignment of the muscle fibers that results in a higher force output. Upon electrical stimulation, the biobot exerts a directional swimming motion at the liquid-air interface, achieving a maximum velocity of 800 µm/s, 791 orders of magnitude higher than the fastest skeletal muscle-based swimming biobot up to date, providing a useful tool to create advanced robotic systems with programmable actuation.