Bistable soft jumper capable of fast response and high takeoff velocity.

In contrast with jumping robots made from rigid materials, soft jumpers composed of compliant and elastically deformable materials exhibit superior impact resistance and mechanically robust functionality. However, recent efforts to create stimuli-responsive jumpers from soft materials were limited in their response speed, takeoff velocity, and travel distance. Here, we report a magnetic-driven, ultrafast bistable soft jumper that exhibits good jumping capability (jumping more than 108 body heights with a takeoff velocity of more than 2 meters per second) and fast response time (less than 15 milliseconds) compared with previous soft jumping robots.

Biomimetic Hydrodynamic Sensor with Whisker Array Architecture and Multidirectional Perception Ability.

The rapid development of ocean exploration and underwater robot technology has put forward new requirements for underwater sensing methods, which can be used for hydrodynamic characteristics perception, underwater target tracking, and even underwater cluster communication. Here, inspired by the specialized undulated surface structure of the seal whisker and its ability to suppress vortex-induced vibration, a multidirectional hydrodynamic sensor based on biomimetic whisker array structure and magnetic 3D self-decoupling theory is introduced. The magnetic-based sensing method enables wireless connectivity between the magnetic functional structures and electronics, simplifying device design and endowing complete watertightness.

Magnetic Soft Catheter Robot System for Minimally Invasive Treatments of Articular Cartilage Defects.

Articular cartilage defects are among the most common orthopedic diseases, which seriously affect patients' health and daily activities, without prompt treatment. The repair biocarrier-based treatment has shown great promise. Total joint injection and open surgery are two main methods to deliver functional repair biocarriers into the knee joint.

Split-Type Magnetic Soft Tactile Sensor with 3D Force Decoupling.

Tactile sensory organs for sensing 3D force, such as human skin and fish lateral lines, are indispensable for organisms. With their sensory properties enhanced by layered structures, typical sensory organs can achieve excellent perception as well as protection under frequent mechanical contact. Here, inspired by these layered structures, a split-type magnetic soft tactile sensor with wireless 3D force sensing and a high accuracy (1.

Thermo-sensitive Sacrificial Microsphere-based Bioink for Centimeter-scale Tissue with Angiogenesis.

Centimeter-scale tissue with angiogenesis has become more and more significant in organ regeneration and drug screening. However, traditional bioink has obvious limitations such as balance of nutrient supporting, printability, and vascularization. Here, with "secondary bioprinting" of printed microspheres, an innovative bioink system was proposed, in which the thermo-crosslinked sacrificial gelatin microspheres encapsulating human umbilical vein endothelial cells (HUVECs) printed by electrospraying serve as auxiliary component while gelatin methacryloyl precursor solution mixed with subject cells serve as subject component.

Perfusable Vessel-on-a-Chip for Antiangiogenic Drug Screening with Coaxial Bioprinting.

Vessel-on-a-chips, which can be used to study microscale fluid dynamics, tissue-level biological molecules delivery and intercellular communication under favorable three-dimensional (3D) extracellular matrix microenvironment, are increasingly gaining traction. However, not many of them can allow for long-term perfusion and easy observation of angiogenesis process. Since angiogenesis is necessary for the expansion of tumor, antiangiogenic drugs play a significant role in cancer treatment.

Functional Blood-Brain Barrier Model with Tight Connected Minitissue by Liquid Substrates Culture.

The functional blood-brain barrier (BBB) model can provide a reliable tool for better understanding BBB transport mechanisms and in vitro preclinical experimentation. However, recapitulating microenvironmental complexities and physiological functions in an accessible approach remains a major challenge. Here, a new BBB model with a high-cell spatial density and tightly connected biomimetic minitissue is presented.

Wireless Flexible Magnetic Tactile Sensor with Super-Resolution in Large-Areas.

Tactile recognition is among the basic survival skills of human beings, and advances in tactile sensor technology have been adopted in various fields, bringing benefits such as outstanding performance in manipulating objects and general human-robot interactions. However, promoting enhanced perception of the existing tactile sensors is limited by their sensor array arrangement and wire-connected design. Here we present a wireless flexible magnetic tactile sensor (FMTS) consisting of a multidirection magnetized flexible film (perception module) and a contactless Hall sensor (signal receiving module).

In situ 3D bioprinting with bioconcrete bioink.

In-situ bioprinting is attractive for directly depositing the therapy bioink at the defective organs to repair them, especially for occupations such as soldiers, athletes, and drivers who can be injured in emergency. However, traditional bioink displays obvious limitations in its complex operation environments. Here, we design a bioconcrete bioink with electrosprayed cell-laden microgels as the aggregate and gelatin methacryloyl (GelMA) precursor solution as the cement.

Liquid Metal Microgels for Three-Dimensional Printing of Smart Electronic Clothes.

Gallium-based liquid metals (LMs), with the combination of liquid fluidity and metallic conductivity, are considered ideal conductive components for flexible electronics. However, huge surface tension and poor wettability seriously hinder the patterning of LMs and their wider applications. Herein, a recyclable liquid-metal-microgel (LMM) ink composed of LM droplets encapsulated into alginate microgel shells is proposed.

Balancing the customization and standardization: exploration and layout surrounding the regulation of the growing field of 3D-printed medical devices in China.

Medical devices are instruments and other tools that act on the human body to aid clinical diagnosis and disease treatment, playing an indispensable role in modern medicine. Nowadays, the increasing demand for personalized medical devices poses a significant challenge to traditional manufacturing methods. The emerging manufacturing technology of three-dimensional (3D) printing as an alternative has shown exciting applications in the medical field and is an ideal method for manufacturing such personalized medical devices with complex structures.

Printability during projection-based 3D bioprinting.

Since projection-based 3D bioprinting (PBP) could provide high resolution, it is well suited for printing delicate structures for tissue regeneration. However, the low crosslinking density and low photo-crosslinking rate of photocurable bioink make it difficult to print fine structures. Currently, an in-depth understanding of the is lacking.

Ultrasonic autofocus imaging of internal voids in multilayer polymer composite structures.

Multilayer polymer composite structures have been playing important roles in various fields, but the voids inside are not allowed in most scenarios. Ultrasonic technology has been widely used to inspect voids in concrete and metal structures. However, the application of ultrasonic imaging in polymer composite structures is severely blocked by the coating and lamination structures and unstable manufacturing induced sound speed variations.

Recyclable conductive nanoclay for direct in situ printing flexible electronics.

Liquid-metal (LM)-based flexible and stretchable electronics have attracted widespread interest in wearable health monitoring, electronic skins, and soft robotics. However, it is challenging to directly pattern LMs on soft substrates to form desirable functional circuits due to their huge surface tension and weak wettability. Here, a recyclable, self-healing conductive nanoclay is prepared by introducing nanoclay into the LM system, which possesses low fluidity and excellent adhesion to soft substrates, and combined with the stamping process, flexible electronics can be printed directly and quickly in situ.

Research on the Fused Deposition Modeling of Polyether Ether Ketone.

As a special engineering polymer, polyether ether ketone (PEEK) has been used widely due to its excellent mechanical properties, high thermal stability, and chemical resistance. Fused deposition modeling (FDM) is a promising process for fabricating PEEK parts. However, due to the semi-crystalline property and high melting point of PEEK, determining appropriate process parameters is important to reduce warpage deformation and improve the mechanical properties of PEEK.

Electrospinning of Nanofibrous Membrane and Its Applications in Air Filtration: A Review.

Air pollution caused by particulate matter and toxic gases is violating individual's health and safety. Nanofibrous membrane, being a reliable filter medium for particulate matter, has been extensively studied and applied in the field of air purification. Among the different fabrication approaches of nanofibrous membrane, electrospinning is considered as the most favorable and effective due to its advantages of controllable process, high production efficiency, and low cost.

Automatic magnetic projection for one-step separation of mixed plastics using ring magnets.

Magnetic projection, a novel separation method proposed recently, can separate multiple mixed materials in an efficient and low-cost way. Although promising, existing magnetic projection method cannot achieve the automatic feeding of mixed materials, which limits its applications. To address this challenge, ring magnets were used to replace conventional square magnets in this research.

High-Performance Auxetic Bilayer Conductive Mesh-Based Multi-Material Integrated Stretchable Strain Sensors.

High-performance stretchable strain sensors, particularly those with high sensitivity and broad sensing range, are highly important for wearable devices. Herein, a novel auxetic bilayer conductive mesh strain sensor (ABSS), composed of multi-hardness silicones, is proposed and fabricated by the direct ink writing 3D printing and ink spraying technique. The bilayer conductive mesh comprises a thin layer of high-conductive and crack-prone single-walled carbon nanotubes (SWCNTs) coated on a stretchable carbon-black-doped Ecoflex silicone rubber (CB/Ecoflex) mesh.

Fabrication of a dual-layer cell-laden tubular scaffold for nerve regeneration and bile duct reconstruction.

Tubular scaffolds serve as a controllable extracellular environment to guide the repair and regeneration of tissues. But it is still a challenge to achieve both excellent mechanical properties and cell compatibility of artificial scaffolds for long-term structural and biological stability. In this study, a four-step solution casting method was developed to fabricate dual-layer cell-laden tubular scaffolds for nerve and bile duct regeneration.

Research and Optimization of the Three-Dimensional Printing Unloading Process for the Flexible Support Platform.

At present, a three-dimensional (3D) printing model is unloaded from the working platform manually, which hinders the automation of 3D printing. In this article, a new type of 3D printing auxiliary equipment called flexible support platform is designed to achieve automatic unloading. Unloading problems, especially its principle and influencing factors, are investigated in detail.

A Mechanically Robust and Versatile Liquid-Free Ionic Conductive Elastomer.

Soft ionic conductors, such as hydrogels and ionogels, have enabled stretchable and transparent ionotronics, but they suffer from key limitations inherent to the liquid components, which may leak and evaporate. Here, novel liquid-free ionic conductive elastomers (ICE) that are copolymer networks hosting lithium cations and associated anions via lithium bonds and hydrogen bonds are demonstrated, such that they are intrinsically immune from leakage and evaporation. The ICEs show extraordinary mechanical versatility including excellent stretchability, high strength and toughness, self-healing, quick self-recovery, and 3D-printability.

A flexible porous chiral auxetic tracheal stent with ciliated epithelium.

Tracheal stent placement is a principal treatment for tracheobronchial stenosis, but complications such as mucus plugging, secondary stenosis, migration, and strong foreign body sensation remain unavoidable challenges. In this study, we designed a flexible porous chiral tracheal stent intended to reduce or overcome these complications. The stent was innovatively designed with a flexible tetrachiral and anti-tetrachiral hybrid structure as the frame and hollows filled with porous silicone sponge.

Development of 3D bioprinting: From printing methods to biomedical applications.

Biomanufacturing of tissues/organs is our big dream, driven by two needs: organ transplantation and accurate tissue models. Over the last decades, 3D bioprinting has been widely applied in the construction of many tissues/organs such as skins, vessels, hearts, , which can not only lay a foundation for the grand goal of organ replacement, but also be served as models committed to pharmacokinetics, drug screening and so on. As organs are so complicated, many bioprinting methods are exploited to figure out the challenges of different applications.

Hydrogels: The Next Generation Body Materials for Microfluidic Chips?

The integration of microfluidics with biomedical research is confronted with considerable limitations due to its body materials. With high content of water, hydrogels own superior biocompatibility and degradability. Can hydrogels become another material choice for the construction of microfluidic chips, particularly biofluidics? The present review aims to systematically establish the concept of hydrogel-based microfluidic chips (HMCs) and address three main concerns: i) why choosing hydrogels? ii) how to fabricate HMCs?, and iii) in which fields to apply HMCs? It is envisioned that hydrogels may be used increasingly as substitute for traditional materials and gradually act as the body material for microfluidic chips.