The swimming locomotion of fish involves a complex interplay between a deformable body and induced flow in the surrounding fluid. While innovative robotic devices, inspired by physicomechanical designs evolved in fish, have been created for underwater propulsion of large swimmers, scaling such powerful locomotion into micro-/nanoscale propulsion remains challenging. Here, a magnetically propelled fish-like artificial nanoswimmer is demonstrated that emulates the body and caudal fin propulsion swimming mechanism displayed by fish. To mimic the deformable fish body for periodic shape changes, template-electrosynthesized multisegment nanowire swimmers are used to construct the artificial nanofishes (diameter 200 nm; length 4.8 μm). The resulting nanofish consists a gold segment as the head, two nickel segments as the body, and one gold segment as the caudal fin, with three flexible porous silver hinges linking each segment. Under an oscillating magnetic field, the propulsive nickel elements bend the body and caudal fin periodically to generate travelling-wave motions with speeds exceeding 30 μm s . The propulsion dynamics is studied theoretically using the immersed boundary method. Such body-deformable nanofishes exhibit a high swimming efficiency and can serve as promising biomimetic nanorobotic devices for nanoscale biomedical applications.

Recent strides in micro‐ and nanofabrication technologies have enabled researchers to design and develop micro‐ and nanoscale robotic systems with enhanced power, functionality, and versatility. Because of their capability of remote actuation and navigation, synthetic micro‐ and nanomotors powered by oscillating magnetic fields have recently gained considerable attention. In this article, a new type of magnetic surface walker that can achieve speeds of up to 18.6 µm s−1 (≈4 body length s−1) in an oscillating magnetic field operated at 25 Hz and ≈2.7 mT is reported. Two magnetic Janus microspheres spontaneously form a microdimer via magnetic dipolar interactions, and this microdimer rolls its two “feet” back and forth in an alternating fashion. In addition to propulsion, the oscillating magnetic field can also precisely steer these surface walkers through complicated structures, and an extensive discussion of their performance in various experimental conditions is provided. The reported propulsion mechanism opens new possibilities for the design of remotely actuated microrobots for a wide range of applications.

It is of great interest and big challenge to control the collective behaviors of nanomotors to mimic the aggregation/separation behavior of biological systems. Here, a light‐acoustic combined method is proposed to control the aggregation/separation of artificial nanomotors. It is shown that nanomotors aggregate at the pressure node in acoustic field and afterward present a collective “firework” separation behavior induced by light irradiation. The collective behavior is found to be applicable for metallic materials and polymers even different light wavelengths are used. Physical insights on the collective firework behavior resulting from the change of acoustic streaming caused by optical force are provided. It is found that diffusion velocity and diffusion region of cluster can be controlled by adjusting light intensity and acoustic excitation voltage, and irradiation direction, respectively. This harmless, controllable, and widely applicable method provides new possibilities for groups of nanomachines, drug release, and cargo transport in nanomedicine and nanosensors.

We developed a transmission diffraction grating-based spectroscopic single-molecule localization microscopy (sSMLM) to collect the spatial and spectral information of single-molecule blinking events concurrently. We characterized the spectral heterogeneities of multiple far-red emitting dyes in a high-throughput manner using sSMLM. We also investigated the influence of spectral dispersion on the single-molecule identification performance of fluorophores with large spectral overlapping. The carefully tuning of spectral dispersion in grating-based sSMLM permitted simultaneous three-color super-resolution imaging in fixed cells with a single objective lens at relatively low photon budget. Our sSMLM has a compact optical design and can be integrated with conventional localization microscopy to provide add-on spectroscopic analysis capability.

Self-propelled micro- and nanoscale robots represent a rapidly emerging and fascinating robotics research area. However, designing autonomous and adaptive control systems for operating micro/nanorobotics in complex and dynamically changing environments, which is a highly demanding feature, is still an unmet challenge. Here we describe a smart microvehicle for precise autonomous navigation in complicated environments and traffic scenarios. The fully autonomous navigation system of the smart microvehicle is composed of a microscope-coupled CCD camera, an artificial intelligence planner, and a magnetic field generator. The microscope-coupled CCD camera provides real-time localization of the chemically powered Janus microsphere vehicle and environmental detection for path planning to generate optimal collision-free routes, while the moving direction of the microrobot toward a reference position is determined by the external electromagnetic torque. Real-time object detection offers adaptive path planning in response to dynamically changing environments. We demonstrate that the autonomous navigation system can guide the vehicle movement in complex patterns, in the presence of dynamically changing obstacles, and in complex biological environments. Such a navigation system for micro/nanoscale vehicles, relying on vision-based close-loop control and path planning, is highly promising for their autonomous operation in complex dynamic settings and unpredictable scenarios expected in a variety of realistic nanoscale scenarios.

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Synergizing grayscale photopolymerization and meniscus coating processes, rapid 3D printing of optical lenses is reported previously using projection microstereolithography (PµSL) process. Despite its 14 000‐fold‐improved printing speed over the femtosecond 3D printing process, PµSL still consumes significant amount of the fabrication time for precise recoating 5 µm thick fresh resin layers. At the reported speed of 24.54 mm3 h−1, 3D printing of the millimeter‐size lenses still takes hours. To further improve the printing speed, the microcontinuous liquid interface production process is implemented to eliminate the time‐consuming resin recoating step. However, the micrometer‐size pores in the Teflon membrane needed for oxygen transportation are found to completely spoil the surface smoothness. The use of polydimethylsiloxane thin film possessing much refined nanoscopic porosities as the functional substitute of Teflon membrane is reported to significantly reduce the surface roughness to 13.7 nm. 3D printing of 3 mm high aspherical lens in ≈2 min at a 200‐fold‐improved speed at 4.85 × 103 mm3 h−1 is demonstrated. The 3D printed aspherical lens has the demonstrated imaging resolution of 3.10 µm. This work represents a significant step in tackling the speed‐accuracy trade‐off of 3D printing process and thus enables rapid fabrication of customized optical components.

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