Bio‐hybrids: When Robots Come Alive

Abstract

Bio-hybrid robots are engineered systems that integrate living biological components (such as cells, tissues, or microorganisms) with synthetic structures to enable sensing, actuation, and adaptive behaviors beyond the reach of conventional machines. This merging of the animate and the artificial blurs boundaries, crafting systems where biology is not merely mimicked, but embodied and active. Bio-hybrid robotics invites life itself into the circuit, creating entities that sense, grow, adapt, and participate. These systems take heterogeneous forms, from muscle cells that contract to drive motion in bio-actuators to microbial communities that serve as engines of locomotion or computation. What began as scientific curiosity has become a field reshaping our notions of intelligence, adaptability, and materiality, where the robot becomes more than a machine: it becomes a host for biological intelligence, a platform for co-evolution, and a mirror reflecting our evolving concepts of agency, autonomy, and design. The contributions featured in this special issue, “Bio-hybrids: When Robots Come Alive,” showcase the diversity and ingenuity of bio-hybrid robotics, from microrobots animated by bacterial activity to proprioceptive muscle-driven actuators and insect-machine cyborgs. Together, these works paint a compelling picture of an emerging class of biointelligent systems: responsive, adaptive, and alive in more ways than one. At the heart of this issue are several breakthroughs in skeletal muscle-based bioactuators, which embody the promise of integrating contractile tissue with synthetic frameworks for soft, life-like motion. Bartolucci A. et al. (10.1002/aisy.202400989) presented a monolithic biohybrid flexure mechanism, consisting of a tubular biohybrid flexure mechanism powered by bioengineered skeletal muscle tissue which demonstrated the potential for compact, muscle-powered robotic systems with integrated actuation and compliance. In this study, the soft silicone structure converts muscle contractions into bending motion, aided by integrated cylindrical pillars for effective force transmission. As proved by performance tests and simulations, such a design offers enhanced contractility and scalability, especially with reduced diameters, providing a simple, robust solution for advancing next-generation, miniaturized biohybrid robots. Lai S. et al. (10.1002/aisy.202400407) introduced a soft bioactuator combining 3D-bioengineered skeletal muscle with organic transistor-based sensors for real-time force monitoring. The system converts muscle contractions into electrical signals, enabling precise performance tracking. Unlike traditional sensors, the transistor-based design offers tunable sensitivity via gate voltage modulation. Moreover, to advance proprioceptive sensing and enable dynamic feedback control, we introduced a soft, fiber-shaped piezoresistive sensor that integrates with engineered skeletal muscle tissue and allows for real-time sensing of low-strain contractions under electrical stimulation (10.1002/aisy.202400413). By feeding this sensory data into a control system, we demonstrated the first proprioceptive biohybrid robot capable of autonomous response to its contraction state. This advancement marks a significant step toward intelligent biohybrid systems with decision-making capabilities, opening new possibilities for biomedical models, implantable devices, and next-generation soft robotics. To truly advance biological robotics, it is essential to move beyond actuation alone and explore functions such as homeostatic regulation and adaptive environmental sensing, roles that, in our bodies, are seamlessly orchestrated through systems like the skin. Extending the paradigm of functional integration, another group presented a skin-covered biohybrid robotic finger with a bilayered, permeable support that maintains tissue hydration, highlighting the importance of physiological environments for sustaining biological function wi