Dielectric elastomers (DE) can potentially generate large electrically induced strains with high energy and power densities. DE are often based on commercial acrylic and silicone elastomers, each having their respective limitations. A processable, high-performance dielectric elastomer (PHDE) with a bimodal network structure will be presented. Its electromechanical properties are tailored to obtain maximum areal strain greater than 100% without prestretching. A hybrid stacking process enables multilayer actuators that maintain the high actuation performance of single-layer films.

Varifocal lenses are a lens with different focal lengths and, therefore, magnification. These are used extensively in the optics industry as progressive lenses in eyewear. A focal length gradient exists along the lens height, so objects magnify as the user looks downwards. Unfortunately, progressive lenses are rigid materials making them closer to quasi-varifocal lenses. In this present study, varifocal lenses can change focal length to a constant value. This study investigates polyvinyl chloride (PVC) gel and Electrohydraulic Actuators Powered by Induced Interfacial Charges (EPIC) actuators as varifocal lenses. Polyvinyl chloride (PVC) gels are a new type of dielectric elastomer actuator only investigated at the start of the century. The transparent gels are known for producing displacement under an effective voltage in a mechanism known as anodophilic creep, the axisymmetric tendency to deform towards the anode surface. The EPIC actuator is a novel application of PVC gels that places

We will present an insect-scale aerial robot that is powered by power-dense dielectric elastomer actuators (DEAs). The DEAs have high power density (>500 W/kg), long life-time (>2 million cycles), and require a driving voltage of 500 V. The 680 mg robot can perform 40-second controlled hovering flight as well as acrobatic maneuvers such as somersaults in 0.16 second. It can recover from in-flight collisions and endure severe damage. These insect-like flight capabilities are absent in existing aerial robots driven by rigid actuators.

We present fully-printed, stretchable, hydraulically-amplified mm-scale zipping electrostatic actuators for both quasi static and high frequency actuation. Inkjet printing of silicones, stretchable conductors and sacrificial materials enables high design flexibility of both actuators and array configurations. The 5 mm wide actuators generate displacement and forces well above haptic perception threshold values from DC to 200 Hz, as shown with user tests. Parallel fluid filling combined with independent sealing of each pouch enables arrays of self-contained fluidic actuators with no cross-talk. This work enables customizable wearables for realistic cutaneous haptic feedback.

This presentation describes the design, manufacturing and testing of an inflatable Dielectric Elastomer Generators (DEGs) with a stadium shape that is intended to be used as integrated prime-mover and power-take-off system of a submerged-membrane pressure-differential Ocean Wave Energy Converter (OWEC). Results highlight the good performances of the developed stadium-shape DEG and its potentialities within the considered OWEC.

Dielectric elastomers based on the commercial VHB tapes have been widely used for soft actuators due to their large electrically driven actuation strain, low cost, and high work density. However, the VHB films require prestretching to overcome electromechanical instability and have high viscoelasticity. In this work, we report a hybrid manufacturing approach to fabricate prestrain-locked high-performance dielectric elastomer (VHB-IPN-P) thin films and multilayer stacks. Four-layer stacks combing the VHB-IPN-P films and bilayer electrodes were fabricated via hybrid process to obtain strong inter-layer bonding and structural robustness of the stacks.

3D printing of dielectric elastomer transducers (DET) would significantly accelerate their application in soft robotics. Direct ink writing (DIW) of DET is limited by multiple factors, such as the need for a multi-material printing of dielectric and compliant electrodes and the relatively large thickness, high stiffness, and poor mechanical properties of elastomers. Increasing the permittivity of elastomers is the only tunable material parameter, which can reduce the actuation voltage, or increase the sensor signal, as the minimum thickness is fixed by the printing resolution. We present DIW printable high-permittivity polysiloxanes. Besides the high-permittivity further material parameters and interdependencies between ink requirements and final material performance are explored. The facile printing of these high-permittivity dielectrics with standard 3D printers is demonstrated. Lastly, the performance of various DIW printed DETs are presented.

Carbon materials are the key to a clean, safe, and sustainable working environment and advanced energy-related devices because they can be reused, recycled, and repurposed. However, effort is necessary to make them ideal candidates for such applications. Here, we design unprecedented carbon materials in the form of covalent-organic and metal-organic frameworks having antagonistic properties to achieve the desirable electro-active artificial muscles. A careful structural investigation is carried out to determine the structure–property relationship, while the fascinating properties of them are validated by real-field demonstrations. The proposed carbon materials show significantly high blocking force, that is ≈30 times of its weight and high bending deflection with fast rising.

We report electrically shielded capacitive stretchable force sensors, that simultaneously measure normal and shear strains, even near electric sparks. The device consists of an outer conductive stretchable shielding layer (carbon-loaded silicone) and a central silicone layer with embedded air channels and three liquid metal electrodes. We report sub-mN force resolution in both normal and shear directions, can measure forces larger than 10 N, and operate reliably after repeated loading to 20 N load. Performance is unaffected by nearby high DC and AC electric fields, allowing use in a wide range of robotic sensing applications.

Metal organic frameworks (MOFs) are a new generation of functional material which amalgamate favorable properties of both organic materials and inorganic useful metals. Owing to this harmony of traits, these MOFs have been employed as active catalysts, gas separators and storage materials. A new avenue recently established is their utilization as active electrode material for EAP actuators. This study introduces a technique to tailor the desirable properties of MOF derivatives. It is found herein for a novel Co-MOF material, that by tuning synthesis parameters the pore size and hence active surface area of the as-synthesized Co-MOF derivatives can be enhanced. These novel Co-MOF derivatives (CoPCS) show drastically improved electrochemical properties and far superior actuation in terms of robustness and durability.

These electroactive gel polymers, commonly PVC-based, have been widely studied regarding their actuation abilities. As far as electromechanical theory, the currently accepted mechanism for polymer gel actuation has been primarily attributed to mobile plasticizer migration towards the space charge layer near the anode. The anodophilic nature of the plasticizer provides a variety of potential applications, largely dependent on electrode geometry and configuration. As an artificial mechanotransductor however, the current hypothesis of a polymer gel’s sensing mechanism has been recently attributed to the phenomenon known as Langmuir adsorption. Upon applying a compressive strain to these soft sensors, plasticizer will exhibit migration towards the polarized adsorbed layer at the electrode interface. In this study, an application-based approach is considered to further exercise the content of the suggested polymer gel MET theory. Due to its compliant nature, the polymer gel sensor (PVC and

The demand for lightweight designs of electronics has grown in recent years. Therefore, to meet the demand, novel methods in material and product development are essential. An easy way of achieving lightweight energy storage is utilizing electroactive polymers such as ionic polymer metal composite (IPMC) materials. This work investigates the effect of cracks caused by tensile loading on the electrical/electrochemical performance of IPMC-based capacitors. The IPMC capacitor maintains its capacitance during minor cracking in the Pt electrodes from high tensile mechanical loads, then decreases. The reduction in capacitance measured with increasing strain displays a high correlation with the number of cracks.

a low temperature fast synthetic strategy is adopted for directly growing MnBTC MOFs on conductive Ti3C2Tx MXene surface to achieve a smart hybrid conductive and hierarchical porous structure Ti3C2Tx MnBTC materials. Then, a flexible actuator membrane is fabricated by sandwich layer by layer structure with PEDOT:PSS embedding mobile ionic liquid (EMIM-BF4) and used for electroactive artificial muscles. The newly developed actuator demonstrates excellent actuation performance including highly bending displacement (12.5 mm) and ultrafast response time (0.77 s) under a low driving voltage (0.5V), along with wide frequency response (0.1 to 10 Hz) and excellent long-term durability (12 hr, 98% retention).

Almost 100 years ago W.B. Wiegand first introduced of a solid-state engine that converted heat into continuous mechanical motion using the contractile properties of a thermally-responsive actuating material. Then and now these engines are considered as one of the few potentially viable methods for harnessing ‘low grade waste heat’ as electrical power. In this talk we consider new opportunities afforded by recently developed artificial muscle materials. Using established engine designs we develop a theoretical connection between engine mechanical output and the characteristics of the actuator material to compare the performances of vulcanised rubber, shape memory alloys and twisted and coiled polymer fiber artificial muscles. We identify the properties needed in actuator materials to maximise engine output and we speculate on possible material structures that may achieve enhanced engine performance.

Nylon actuators yield a large reversible strain (5-20%+), are compact (300-µm) and provide a low-cost option for biomedical applications. We propose to develop an active textile composed of cotton, silver-coated nylon, and nylon actuators. We will assess the feasibility of nylon actuators to generate effective cycle rates and compression pressures similar to those of clinically effective pneumatic compression pumps. Our aim is to establish correlations between three nylon actuator configurations (parallel, parallel at 30°, and crisscrossed at 30°), thermal distribution, and compression pressure, as well as between power input and nylon actuator cycle rate. A microcontroller unit (MCU) and a pressure sensor will be developed for the nylon actuators to ensure that the actuators are under constant strain, while monitoring pressure, current, voltage and temperature. The development of an actively contracting textile could have significant benefits for portable compression therapies.