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Biological organisms present marvelous morphing behaviors from the quiescent blooming of flowers to the energetic wing‐flapping of birds that have always inspired humans to design better‐engineered products. The diversity of natural motion is attributed primarily to the intricate and hierarchical structure of actuators that are self‐assembled from nanoscale structures to superstructures. Compared to the biological actuators, their manmade counterparts, often with significantly limited capabilities, are fabricated from various materials with relatively simple structures using limited fabrication techniques. With the rapid developments in technologies that require soft robotics and human‐machine interfaces, there is increasing demand for soft actuators with improved capabilities such as larger output force, repeatability, and a more comprehensive range of motion. Biological actuators provide critical insights into the structure‐function relationship and offer exciting concepts to advance the science and technology of artificial soft actuators. Here, the design approaches found in natural actuation systems are discussed from the nanoscale to the highest levels in the structural hierarchy and the physical principles involved in their diverse actuation capabilities. In that context, finally, the fabrication techniques that have been utilized for manmade soft actuators, with a focus on the advantages, challenges, and concepts for potential future developments are reviewed. [ABSTRACT FROM AUTHOR]

Soft robotic manipulators are continuum robots made of soft materials and flexible components. The goal of soft robotic manipulators research is to enable these manipulators to adapt their shapes to cluttered environments and to have safer interactions with human. However, there is still a problem with effectively using soft robotic manipulators in practical applications. The challenges of soft robotic manipulators in terms of materials and structure design, stiffness control, perception, and function control remain to be overcome. Here, an overview of recent advances in this field is presented, covering device architectures, actuation, variable stiffness, and sensing. Actuator technologies are discussed and roughly divided into three categories: a) tendon‐driven actuation, b) fluidic actuation, and c) stimuli‐responsive actuation, which is based on smart materials. Considering the working principle of stiffness variation technologies, stiffness variation technologies can be divided into two categories: a) using the interactions between structural elements, b) direct material rigidity tuning strategies. A briefly review of soft sensing technologies is presented. From the functional perspective, sensor technologies are divide into two categories: proprioception and exteroception. A conception for designing soft robotic manipulators is proposed from the perspective of soft robotic manipulator applications. Finally, the challenges this field faces are discussed. [ABSTRACT FROM AUTHOR]

Magnetism‐based systems are widely utilized for sensing and imaging biological phenomena, for example, the activity of the brain and the heart. Magnetomyography (MMG) is the study of muscle function through the inquiry of the magnetic signal that a muscle generates when contracted. Within the last few decades, extensive effort has been invested to identify, characterize and quantify the magnetomyogram signals. However, it is still far from a miniaturized, sensitive, inexpensive and low‐power MMG sensor. Herein, the state‐of‐the‐art magnetic sensing technologies that have the potential to realize a low‐profile implantable MMG sensor are described. The technical challenges associated with the detection of the MMG signals, including the magnetic field of the Earth and movement artifacts are also discussed. Then, the development of efficient magnetic technologies, which enable sensing pico‐Tesla signals, is advocated to revitalize the MMG technique. To conclude, spintronic‐based magnetoresistive sensing can be an appropriate technology for miniaturized wearable and implantable MMG systems. [ABSTRACT FROM AUTHOR]

Nano or microsized particles have been a research focus for decades, and the advancement of microfluidic technologies provides alternative strategies for the synthesis of such materials for various applications. Recent advances of using different microfluidic devices (MDs), including continuous laminar flow, segmented flow, droplet‐based, and other non‐chip‐based microreactors, for the synthesis of nano or microsized particles with specific properties are reviewed, along with their biomedical applications. Different categories of particles fabricated in MDs are summarized to highlight the wide application of the processing platform in the development of novel functional materials. [ABSTRACT FROM AUTHOR]