This review covers recent advancements in the field of bioinspired soft robotics, with a primary focus on the last 4 years (2017)(2018)(2019)(2020). The review serves as a toolbox for an interdisciplinary audience interested in the most recent bioinspired soft robotic technologies. In particular, it highlights and explores the vital components of soft robots, focusing on the enabling mechanisms and their biological inspirations. The first section discusses the materials used to fabricate soft bio inspired robots. Soft bioinspired actuation and sensing are then discussed, exploring their capabilities and implementation by researchers. Existing challenges and future potentials of bioinspired soft robots are addressed in the concluding remarks. This review provides engineers and scientists with the latest technological advancements and information needed for designing and developing the next generation of soft bioinspired robotic systems. The future applications of these robots will be grand and limitless. Materials Used for Bioinspired Sensors and ActuatorsClassical robotic systems are comprised of rigid bodies, actuators, and sensors. Unfortunately, many of these well-developed actuators and sensors are not transferable to soft bodies. Thus, researchers working in soft robotics need to reinvent actuators and sensors for soft moving bodies. Biological organisms can be an excellent inspiration for designing these soft actuators and sensors, allowing for their integration in both soft and rigid bodies. The design process of soft actuators and sensors have to be initiated with material selection and composition, for they are foundations upon which the actuators and sensors will be built around. Presently, a diversified list of materials has been used in the development of soft robotic systems. This section will cover some of the latest advancements in the last 4 years in the area of material selection and composition for the design and development of soft bioinspired actuators and sensors.During the past 4 years, researchers have produced soft bioinspired actuators and sensors using biological material such as muscle tissue, [23,24] and plant fibers; [25] carbon-based materials such as graphite and graphene oxide (GO) [26][27][28][29][30][31] and carbon nanotubes (CN); [32,33] hydrogel materials such as poly(Nisopropylacrylamide) (PNIPAM), [34,35] liquid crystal elastomers (LCE), [36] dielectric elastomers (DE), [37] and ionic polymermetal composites (IPMC). [38] An overview of these materials (Figure 1), along with their underlying mechanisms, are discussed below.Biological systems can perform complex tasks with high compliance levels. This makes them a great source of inspiration for soft robotics. Indeed, the union of these fields has brought about bioinspired soft robotics, with hundreds of publications on novel research each year. This review aims to survey fundamental advances in bioinspired soft actuators and sensors with a focus on the progress between 2017 and 2020, providing a primer for the materials used i...

needle steering is a technology for guiding needles around sensitive internal obstacles in minimally invasive surgery. traditional techniques apply rotation at the base of a needle with an asymmetric tip, enabling steering through the redirection of radial forces. Magnetic steering of catheters and continuum manipulators is another technology that allows steering of a shaft in the body. Both of these techniques rely on mechanical or manual shaft advancement methods. needle steering has not achieved widespread clinical use due to several limitations: 1-buckling and compression effects in the shaft and needle rotation cause excessive tissue damage; 2-torsion effects on the shaft and needle deflection at tissue boundaries lead to difficulty in control; and 3-restricted radius of curvature results in limited workspace. Magnetically steered catheters and continuum manipulators also suffer from limited curvature and the possibility of buckling. This paper proposes a novel needle steering method empowered by electromagnetic actuation that overcomes all of the aforementioned limitations, making it a promising option for further study toward healthcare applications. Needles are among the least invasive surgical tools available to doctors and surgeons. The wound caused by a needle is easily and quickly repaired by the body and is, therefore, the preferred method of administering or drawing liquids to or from the body. Inflexible needles can only reach a target just under the skin, and not one protected by bone or sensitive tissues. However, needles with flexible, long shafts can be steered around these internal anatomies. The benefits of the ability to tightly steer around sensitive or protective internal obstacles can be seen in several medical applications. This ability is especially significant during treatment of glioblastoma, where tumors can develop and extend into sensitive tissues such as venous sinuses, the brain stem, or deep cerebellar nuclei. These obstacles frequently prevent the ability to locally deliver drugs, and can even render resection impossible 1. Thus, the treatment of deeply embedded cancerous tumors in the brain via a compartmental therapy approach, specifically but not limited to Convection-Enhanced Delivery (CED), characterizes a specific clinical application where needle steering with very tight curvature would be highly effective. CED is a targeted drug delivery technique to treat various conditions in the brain. This technique uses a pressure gradient to deliver pharmaceuticals more successfully across the blood-brain barrier 2. Another application where tight needle steering would provide clinical benefits is in radiofrequency ablation (RFA) of liver tumors. In RFA, a tumor or other target tissue is thermally destroyed by heat induced by high frequency alternating current, applied at the end effector of a small electrode 3. This technique is often hindered by the maneuverability of the ablation needle; Adebar et al. specifically pointed out the need for tighter needle steering in order to tar...

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Transitional compositions or phase-changing structures in specific layers can respond to environmental changes differently and show intelligent behaviors. For example, smart polymers with shape morphing capabilities (e.g., external field-controlled untethered...

Variable electronics are vital in tunable filters, transmitters, and receivers, among other applications. In addition, the ability to remotely tune soft capacitors, resistors, and inductors is important for applications in which the device is not accessible. In this paper, a uniform method of remotely tuning the characteristic properties of soft electronic units (i.e. inductance, capacitance, and resistance) is presented. In this method, magnetically actuated ferrofluid mixed with iron powder is dragged in a soft fluidic channel made of polydimethylsiloxane (PDMS) to tune the electrical properties of the component. The effects of position and quantity of the ferrofluid and iron powder are studied over a range of frequencies, and the changes in inductance, capacitance, resistance, quality factor, and self-resonance frequency are reported accordingly. The position plays a bigger role in changing inductance, capacitance, and resistance. With the proposed design, the inductance can be changed by 20.9% from 3.31 μH for planar inductors and 23% from 0.44 μH for axial inductors. In addition, the capacitance of capacitors and impedance of resistors can be changed by 12.7% from 2.854 pF and 185.3% from 0.353 kΩ, respectively. Furthermore, the changes in the inductance, capacitance, and resistance follow “quasi-linear profiles” with the input during position and quantity effect experiments.