Microrobots have been developed for applications in the submillimeter domain such as the manipulation of micro-objects and microsurgery. Rapid progress has been achieved in developing miniaturized components for microrobotic systems, resulting in a variety of functional microactuators and soft components for creating untethered microrobots. Nevertheless, the integration of microcomponents, especially the assembly of actuators and mechanical components, is still time-consuming and has inherent restrictions, thus limiting efficient fabrications of microrobots and their potential applications. Here, we propose a method for fabricating microrobots in situ inspired by the construction of microsystems in living organisms. In a microfluidic chip, hydrogel mechanical components and artificial muscle actuators are successively photopatterned from hydrogel prepolymer and biomolecular motors, respectively, and integrated in situ into functional microrobots. The proposed method allows the fast fabrication of microrobots through simple operations and affordable materials while providing versatile functions through the precise spatiotemporal control of in situ integration and reconfiguration of artificial muscles. To validate the method, we fabricated microrobots to elicit different motions and on-chip robots with unique characteristics for microfluidic applications. This study may establish a new paradigm for microrobot integration and lead to the production of unique biohybrid microrobots with various advantages.

Biobot-based insects have been investigated so far for various applications such as search and rescue operations, environmental monitoring, and discovering the environment. These applications need a strong international collaboration to complete the tasks. However, during the COVID-19 pandemic, most people could not easily move from one country to another because of the travel ban. In addition, controlling biobots is challenging because only experts can operate the cockroach behavior with and without stimulated response. In order to solve this issue, we proposed a user-friendly teleoperation user interface (UI) to monitor and control the biobot between Japan and Bangladesh without onsite operation by experts. This study applied Madagascar hissing cockroaches (MHC) as a biobot hybrid robot. A multithreading algorithm was implemented to run multiple parallel computations concurrently on the UI. Virtual network computing (VNC) was implemented on the teleoperation UI as remote communication for streaming real-time video from Japan to Bangladesh and sending remote commands from Bangladesh to Japan. In the experiments, a remote operator successfully steered the biobot to follow a predetermined path through a developed teleoperation UI with a time delay of 275 ms. The proposed interactive and intuitive UI enables a promising and reliable system for teleoperated biobots between two remote countries.

A printable artificial muscle assembled from biomolecular motors, which we have recently developed, showed great potential in overcoming the design limitations of conventional biohybrid robots as a new bio-actuator. Characterizing its contractility for extending its applicability is important. However, conventional measurement methods are composed of complex operations with poor reproducibility, flexibility, and real-time responsiveness. This study presents a new method for measuring the contractile force generated by artificial muscles. A measurement system was constructed, wherein artificial muscles were patterned by UV laser scanning in an oil-sealed microchamber, and the contractile force was measured in real time using a microforce sensor extended by a 3D-printed microcantilever. The measurement accuracy of the sensor was ensured through calibration and correction. For demonstration purposes, a series of contractile measurements were carried out using the proposed system. The relationship between contractile force and the dimensions of the activation space of the artificial muscles, as well as the tensile properties of the contracted muscle chain were evaluated. The results will help characterize the contractile properties of the artificial muscle and lay the foundations for its further application in biohybrid robotics.

Soft robots have often been proposed for medical applications, creating human-friendly machines, and dedicated subject operation, and the pneumatic actuator is a representative example of such a robot. Plants, with their hingeless architecture, can take advantage of morphology to achieve a predetermined deformation. To improve the modes of motion, two pneumatic actuators that mimic the principles of the plants (the birds-of-paradise plant and the waterwheel plant) were designed, simulated, and tested using physical models in this study. The most common deformation pattern of the pneumatic actuator, bending deformation, was utilized and hingeless structures based on the plants were fabricated for a more complex motion of the lobes. Here, an ABP (actuator inspired by the birds-of-paradise plant) could bend its midrib downward to open the lobes, but an AWP (actuator inspired by the waterwheel plant) could bend its midrib upward to open the two lobes. In both the computational and physical models, the associated movements of the midrib and lobes could be observed and measured. As it lacks multiple parts that have to be assembled using joints, the actuator would be simpler to fabricate, have a variety of deformation modes, and be applicable in more fields.

The fabrication of arteriole‐scale blood vessel‐like structures remains a critical barrier in engineering thick, vascularized tissues. Despite advances in artery‐scale tubular scaffolds and capillary‐scale networks, creating tubular structures at the arteriole scale (50 µm–1 mm) remains challenging because of the intrinsic softness of hydrogels. Here, we present an optofluidic additive‐manufacturing method based on meniscus‐guided interfacial polymerization within microchannels. Surface tension forms a stable oil–hydrogel interface, where ultraviolet (UV) irradiation selectively polymerizes the hydrogel precursor into ring‐like structures. Sequential ring formation along the channel enables in situ assembly of hollow tubular constructs with inner diameters precisely controlled by the axial irradiation position. The method is further extended to biologically relevant softer hydrogels, and UV attenuation analysis and PBS incubation support the structural uniformity and stability of the fabricated tubes. Hydrogel tubes with straight, curved, and branching configurations are fabricated using corresponding microchannel architectures. Multi‐material tubular structures with radial and axial compositions are also realized while reducing material‐switching steps and waste. Furthermore, synchronizing real‐time meniscus detection with UV irradiation enables continuous ring formation and smooth tube walls. This method provides a versatile platform for constructing arteriole‐scale vascular‐like hydrogel structures with controlled geometries, stability, and material compositions.