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The integration of textile-based sensing and actuation elements has become increasingly important across various fields, driven by the growing demand for smart textiles in healthcare, sports, and wearable electronics. This paper presents the development of a small, smart dielectric elastomer (DE)-based sensing array designed for user control input in applications such as human–machine interaction, virtual object manipulation, and robotics. DE-based sensors are ideal for textile integration due to their flexibility, lightweight nature, and ability to seamlessly conform to surfaces without compromising comfort. By embedding these sensors into textiles, continuous user interaction can be achieved, providing a more intuitive and unobtrusive user experience. The design of this DE array draws inspiration from a flexible and wearable version of a touchpad, which can be incorporated into clothing or accessories. Integrated advanced machine learning algorithms enhance the sensing system by improving resolution and enabling pattern recognition, reaching a prediction performance of at least 80. Additionally, the array’s electrodes are fabricated using a novel sputtering technique for low resistance as well as high geometric flexibility and size reducibility. A new crimping method is also introduced to ensure a reliable connection between the sensing array and the custom electronics. The advantages of the presented design, data evaluation, and manufacturing process comprise a reduced structure size, the flexible adaptability of the system to the respective application, reliable pattern recognition, reduced sensor and line resistance, the adaptability of mechanical force sensitivity, and the integration of electronics. This research highlights the potential for innovative, highly integrated textile-based sensors in various practical applications.

This paper introduces the analysis and design of a wave energy converter (WEC) that is equipped with a novel kind of electrostatic power take-off system, known as dielectric elastomer generator (DEG). We propose a modelling approach which relies on the combination of nonlinear potential-flow hydrodynamics and electro-hyperelastic theory. Such a model makes it possible to predict the system response in operational conditions, and thus it is employed to design and evaluate a DEG-based WEC that features an effective dynamic response. The model is validated through the design and test of a small-scale prototype, whose dynamics is tuned with waves at tank-scale using a set of scaling rules for the DEG dimensions introduced here in order to comply with Froude similarity laws. Wave-tank tests are conducted in regular and irregular waves with a functional DEG system that is controlled using a realistic prediction-free strategy. Remarkable average performance in realistically scaled sea states has been recorded during experiments, with peaks of power output of up to 3.8 W, corresponding to hundreds of kilowatts at full-scale. The obtained results demonstrated the concrete possibility of designing DEG-based WEC devices that are conceived for large-scale electrical energy production.

In view of their unique shape morphing behaviour, dielectric elastomer-based minimum energy structures (DEMES) have received an increasing attention in the technology of electroactive soft transduction. Because several of them undergo a time-dependent motion during their operation, understanding their nonlinear dynamic behaviour is crucial to their effective design. Additionally, in the recent past, there has been a growing scientific interest in imparting anisotropy to the material behaviour of dielectric elastomers in view of ameliorating their actuation performance. Spurred with these ongoing efforts, this paper presents an analytical framework for investigating the nonlinear dynamic behaviour of aniso-visco-hyperelastic DEMES actuator with an elementary rectangular geometry. We use a rheological model comprising two Maxwell elements connected in parallel with two single spring elements for modelling the material behaviour of the DE membrane. The governing equations of motion for the underlying non-conservative system are then derived using the Euler–Lagrange equation. The proposed model is used for building insights into the attainable equilibrium states, periodicity of the response as well as the resonant behaviour of the DEMES actuator over a feasible range of anisotropy and viscosity parameters. Our results reveal that the DEMES with hyperelastic material properties exhibits a supercritical pitchfork bifurcation of equilibrium state which is further accelerated in terms of attained equilibrium angle due to membrane anisotropy. A significant enhancement in the equilibrium angle attained by the structure with the extent of membrane anisotropy parameter is observed, indicating a favourable impact of material anisotropy. Poincare maps and phase-portraits are presented for assessing the periodicity of the nonlinear oscillations. The frequency response of the actuator for a combined DC and AC load indicates an upsurge in the resonant frequency with an increase in anisotropy parameter. The underlying analytical model and the trends presented in this study can find their potential use in the design and development of the futuristic anisotropic DEMES actuators subjected to time-dependent actuation.

Rapid energy‐efficient movements are one of nature's greatest developments. Mechanisms like snap‐buckling allow plants like the Venus flytrap to close the terminal lobes of their leaves at barely perceptible speed. Here, a soft balloon actuator is presented, which is inspired by such mechanical instabilities and creates safe, giant, and fast deformations. The basic design comprises two inflated elastomer membranes pneumatically coupled by a pressurized chamber of suitable volume. The high‐speed actuation of a rubber balloon in a state close to the verge of mechanical instability is remotely triggered by a voltage‐controlled dielectric elastomer membrane. This method spatially separates electrically active and passive parts, and thereby averts electrical breakdown resulting from the drastic thinning of an electroactive membrane during large expansion. Bistable operation with small and large volumes of the rubber balloon is demonstrated, achieving large volume changes of 1398% and a high‐speed area change rate of 2600 cm2 s−1. The presented combination of fast response time with large deformation and safe handling are central aspects for a new generation of soft bio‐inspired robots and can help pave the way for applications ranging from haptic displays to soft grippers and high‐speed sorting machines. A voltage‐triggered soft balloon actuator with an impressive displacement (1398% total volume change) at high speed (2600 cm2 s−1 area change rate) is developed by harnessing the mechanical snap‐through and snap‐back instability of a rubber balloon. The trigger actuator is pneumatically coupled to the high‐speed actuator. This concept promises applications in soft bio‐inspired systems in modern robotics and engineering.

Carangidae fish feature streamlined, oval, or rhomboid bodies with flat and high sides, making them adept at swimming swiftly through water with minimal resistance. Dielectric elastomers (DEs), known for their high strain, rapid response times, and high electromechanical coupling efficiency under an electric field, are intelligent materials suitable for creating various actuators widely employed in flexible bionic robots. By utilizing smart material-driven soft fins, bionic robot fish can more realistically simulate the movements of actual fish, improving their swimming performance. In this study, we employed a DE-based actuator to develop a bionic robot fish resembling Carangidae, driven by fins. Leveraging the minimum energy structure of DE material, we designed a structure inspired by the Carangidae family to replicate the fin swing of the bionic robot fish. We investigated the swimming behavior of this bionic robot fish under sinusoidal voltage signals of varying amplitudes and frequencies. The bionic robot fish swims in the medium and/or paired fin (MPF) propulsion mode, achieving a maximum speed of 8.6 mm/s. This work presents a novel scheme and theoretical foundation for the application of dielectric elastomers in bionic Carangidae robots.

This paper presents an overview of cooperative actuator and sensor systems based on dielectric elastomer (DE) transducers. A DE consists of a flexible capacitor made of a thin layer of soft dielectric material (e.g., acrylic, silicone) surrounded with a compliant electrode, which is able to work as an actuator or as a sensor. Features such as large deformation, high compliance, flexibility, energy efficiency, lightweight, self-sensing, and low cost make DE technology particularly attractive for the realization of mechatronic systems that are capable of performance not achievable with alternative technologies. If several DEs are arranged in an array-like configuration, new concepts of cooperative actuator/sensor systems can be enabled, in which novel applications and features are made possible by the synergistic operations among nearby elements. The goal of this paper is to review recent advances in the area of cooperative DE systems technology. After summarizing the basic operating principle of DE transducers, several applications of cooperative DE actuators and sensors from the recent literature are discussed, ranging from haptic interfaces and bio-inspired robots to micro-scale devices and tactile sensors. Finally, challenges and perspectives for the future development of cooperative DE systems are discussed.

Dielectric Elastomer Minimum Energy Structures (DEMES) have the ability of actively adjusting their shape to accommodate complex scenarios, understanding the actuation mechanism of DEMES is essential for their effective design and control, which has rendered them a focus of research in the field of soft robotics. The actuation ability of DEMES is usually influenced by external conditions, among which the electromechanical properties of DE materials are highly sensitive to temperature changes, and the pre-stretch ratio of DE materials has a significant impact on the dynamic performance of DEMES. Therefore, it is necessary to study the effects of temperature and pre-stretch ratio on the nonlinear dynamic behavior of DEMES. In this paper, in response to the lack of research on the influence of DE pre-stretch ratio on the actuation characteristics of DEMES, this paper proposes a systematic modeling and analysis framework that comprehensively considers pre-stretch factors, temperature factors, and viscoelastic factors, and establishes the motion control equation of DEMES affected by the coupling effect of DE pre-stretch ratio and temperature. The proposed analytical framework is used to analyze the evolution of the electromechanical response of DEMES under voltage excitation under the coupling of DE pre-stretch ratio and temperature. The results indicate that the bending angle, inelastic deformation, resonant frequency, and dynamic stability of DEMES can be jointly adjusted by the DE pre-stretch ratio and ambient temperature. A low pre-stretch ratio of DE can lead to dynamic instability of DEMES, while appropriate temperature conditions and higher pre-stretch ratios can significantly improve the actuation ability of DEMES. This can provide theoretical guidance for the design and deformation control of DEMES.

Dielectric elastomer actuators (DEAs) are a promising technology for soft robotics. The use of DEAs has many advantages, including light weight, resilience, and fast response for its applications, such as grippers, artificial muscles, and heel strike generators. Grippers are commonly used as grasping devices. In this study, we focus on DEA applications and propose a technology to expand the applicability of a soft gripper. The advantages of gripper-based DEAs include light weight, fast response, and low cost. We fabricated soft grippers using multiple DEA layers. The grippers successfully held or gripped an object, and we investigated the response time of the grippers and their angle characteristics. We studied the relationship between the number of DEA layers and the performance of our grippers. Our experimental results show that the multi-layered DEAs have the potential to be strong grippers.

The ongoing climate crisis requires innovative methods to maximize renewable and sustainable energy resources. There have been advancements in harvesting energy from ambient motions such as wind, ocean waves, and human movements. Dielectric elastomer generators (DEGs) are a promising option for energy harvesting due to their high energy density and compatibility with low‐frequency oscillations. This review provides an in‐depth overview of DEGs, including electroactive materials, electromechanical characterization, electronics for harvesting, interfacing circuits, prototypes, and challenges. DEGs have the potential to play a significant role in decarbonizing energy for both small‐ and large‐scale applications using ambient energy sources. The ongoing climate crisis requires innovative methods to maximize renewable and sustainable energy resources. Dielectric elastomer generators (DEGs) are a promising option for energy harvesting due to their high energy density and compatibility with low‐frequency oscillations. This review provides an in‐depth overview of DEGs, including electroactive materials, electromechanical characterization, electronics for harvesting, prototypes, and challenges.

Energy generation using dielectric elastomers (DE) has received a great deal of attention due to their light weight, low cost, and high efficiency. This method is an environmentally friendly system that generates electricity without emitting carbon dioxide and without using rare earths, and can contribute to the reduction of global warming. However, this DE system is expected to be used for wearables, such as shoe power generation, because it is not yet possible to make an energy generation element of a very large size. The problem is that this small DE generator can only generate a small amount of energy at one time. Therefore, in order to increase energy generation efficiency, it is necessary to use a material with higher conductivity for the DE electrode. Moreover, since DE energy generation is output at a high voltage, a circuit capable of stepping down with high efficiency is required in order to use this power for ordinary electric appliances. In addition to this, a circuit that can charge the secondary battery with high efficiency from the surplus power obtained by energy generation is also required. However, these are still technically difficult and have hardly been studied so far. We identified a highly efficient step-down circuit using two diaphragm-type DEs with a diameter of 8 cm, dropped 3000 V to 3.3 V, and succeeded in charging the secondary battery. The possibility of wearable or portable energy generation was shown in a commercial manner.