Miniature robots show great potential in exploring narrow and confined spaces to perform various tasks, but many applications are limited by the dependence of these on electrical or pneumatic tethers power supplies outboard. Developing an onboard actuator that is small size powerful enough carry all components a major challenge eliminate need for tether. Bistability can trigger dramatic energy release during switching between 2 stable states, thus providing promising way overcome intrinsic...

Modeling large spatial deflections of flexible beams has been one the most challenging problems in research community compliant mechanisms. This work presents a method called chained spatial-beam constraint model (CSBCM) for modeling bisymmetric CSBCM is based on (SBCM), which was developed purpose accurately predicting nonlinear characteristics their intermediate deflection range. deals with by dividing beam into several elements, each element SBCM, and then assembling deflected elements...

Cables are critical in engineering structures for load‐bearing, electronic connection, and mechanical transmission. Various cable‐crawling robots (CCRs) have been developed to perform scheduled inspection or convey supplies. Most existing CCRs often actuated by motors used large‐scaled structures. The heavy bodies of these can cause damage even casualties once slippage drop occurs. A small lightweight CCR that crawl on thin cables is highly demanded safety narrow confined inner spaces...

Upon stretching, a ribbon kirigami with parallel major cuts exhibits multistable behaviors that can maintain at multiple stable configurations. This work investigates the phenomena of one replaced by wide cut, which wide-cut located cell, configurations, and energy barriers between configurations are explored. It is observed introduction cut results in local symmetry breaking, enabling bidirectional transition such kirigami. The also reveal geometries stretch level enable reprogramable...

Abstract The previously presented Beam Constraint Model (BCM) successfully captures pertinent nonlinearities to predict the constraint characteristics of beam flexures. This has been followed by multiple attempts construct a more comprehensive framework comprising strain energy (SE) principles and complementary (CSE) principles. However, results are still lacking in current literature, especially validation CSE definition, fundamental relations between coefficients, further relationships SE...

Abstract Although energy-based methods have advantages over the Newtonian for kinetostatic modeling, geometric nonlinearities inherent in deflections of compliant mechanisms preclude most theorems. Castigliano's first theorem and Crotti-Engesser theorem, which don't require problem being solved to be linear, are selected construct modeling framework this work. Utilization these two theorems requires explicitly formulating strain energy terms complementary loads, derived based on beam...

In recent years, materials with asymmetric mechanical response properties (mechanical Janus materials) have been found possess numerous potential applications, i.e. shock absorption and vibration isolation. this study, we propose a novel lattice whose can be switched in orientation by plug. Through finite element analysis (FEA) experimental verification, exhibits displacement responses to symmetric forces. Furthermore, such plug structure inside, individual lattices switch the of asymmetry...

Cable-Crawling Robots In article number 2300828, Bo Li, Guimin Chen, and co-workers report a centimeter-scaled cable-crawling robot for thin cables by utilizing multilayered dielectric elastomer actuators. The miniaturized (2.1 g, 43 mm long) can quickly crawl on extremely with different orientations, transport objects, locomote across the water–air interface. Benefit from excellent locomotion performance, be applied to perform inspection maintenance tasks along pre-built inside some...

Abstract Modeling large spatial deflections of flexible beams has been one the most challenging problems in research compliant mechanism. This study presents an approach called chained power series model for modeling defections with uniform rectangular cross section. is based on developed our previous work intermediate deflection range. The splits a beam into several elements and models each element by model, then, all are assembled to form through transformations using quaternions....

Highlights•A unified cut topology results in a family of modular bistable kirigami cells•Kirigami with tension-driven positive/negative Poisson's ratio, bending, and shear•3D produces mechanical coupling multiple deformation modes•Assembled 3D architectures enable self-locked shape morphingSummaryKirigami structures are capable drastically changing their shapes into deployable structures, showing promise for applications space medical implants, transformable robots. This paper proposes cell...

A soft bistable actuator can generate high-speed motion between two prescribed stable positions, which is very useful for boosting the actuation of robots. Generally, stroke such an completely determined once design finalized, prohibits its applications in robots that perform multiple tasks. In current work, a with adjustable characteristics proposed by exploring strain energy landscape, barrier manipulatable via electroactive twisted and coiled polymer fibers. As such, operate either or...

Falls are the second leading cause of accidental or unintentional injuries/deaths worldwide. Accurate pose estimation using commodity mobile devices will help early detection and injury assessment falls, which essential for first aid elderly falls. By following definition fall, we propose a P ervasive ose Est imation scheme fall ( \( ^2 \) ), measures changes in tilt angle height human body. For measurement, leverages pointing device, e.g., smartphone, when unlocking to associate Device...

Although energy-based methods have advantages over the Newtonian for kinetostatic modeling, geometric nonlinearities inherent in deflections of compliant mechanisms preclude most theorems. Castigliano’s first theorem and Crotti-Engesser theorem, which don’t require problem being solved to be linear, are selected construct modeling framework this work. Utilization these two theorems requires explicitly formulating strain energy terms complementary loads, derived based on beam constraint...

Abstract It is very important to clarify the reservoir damage characteristics and mechanism of tight sandstone gas reservoirs in Jinhua-Zhongtai mountain area central SiChuan Basin, put forward technical countermeasures “Double protection” drilling fluid protect environment, which for efficient well construction this area. Through X-ray diffraction, scanning electron microscopy, casting thin sections other testing methods, mineral composition microstructure block were analyzed, potential...