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This paper reviews state-of-the-art dielectric elastomer actuators (DEAs) and their future perspectives as soft actuators which have recently been considered as a key power generation component for soft robots. This paper begins with the introduction of the working principle of the dielectric elastomer actuators. Because the operation of DEA includes the physics of both mechanical viscoelastic properties and dielectric characteristics, we describe theoretical modeling methods for the DEA before

A polymer-waveguide-based transparent and flexible force sensor array is proposed, which satisfies the principal requirements for a tactile sensor working on curvilinear surfaces, such as thinfilm architecture (thickness < 150 μm), localized force sensing (ca. 0-3 N), multiple-point re cognition (27 points), bending robustness (10.8% degradation at R = 1.5 mm), and fast response (bandwidth > 16 Hz).

In this paper, we propose a shape memory alloy (SMA)-based wearable robot that assists the wrist motion for patients who have difficulties in manipulating the lower arm. Since SMA shows high contraction strain when it is designed as a form of coil spring shape, the proposed muscle-like actuator was designed after optimizing the spring parameters. The fabricated actuator shows a maximum force of 10 N and a maximum contraction ratio of 40%. The SMA-based wearable robot, named soft wrist assist (SW

The Ubi-Pen is a pen-like haptic interface incorporating a compact tactile display and a vibrating module. It can represent tactile patterns and provide feedback with the click of a button. It's also applicable to combined force- and tactile-feedback display.

This paper investigates spatiotemporal tactile perceptive characteristics and biomechanical properties of human skin and considers their implications for the design of tactile displays. Three separate experiments were conducted. First, we measured vibrotactile thresholds as a function of frequency of vibration, using a cylindrical contactor of 0.7 mm diameter. The results of our experiment showed similar trends to that of previous physiological results that used a larger contactor. In the second

Developing tunable lenses, an expansion-based mechanism for dynamic focus adjustment can provide a larger focal length tuning range than a contraction-based mechanism. Here, we develop an expansion-tunable soft lens module using a disk-type dielectric elastomer actuator (DEA) that creates axially symmetric pulling forces on a soft lens. Adopted from a biological accommodation mechanism in human eyes, a soft lens at the annular center of a disk-type DEA pair is efficiently stretched to change the

This paper describes the development of a planar distributed tactile display, and tests its effectiveness for displaying textures. The tactile display is composed of a 6/spl times/5 pin array actuated by 30 piezoelectric bimorphs. The pins lie on 1.8 mm centers. Vertical excursion of each pin is controlled over a 0-0.7 mm range. Perceptual experiments were conducted to evaluate the performance of the system under three conditions: active touch, passive touch with vibration, and passive touch wit

This paper describes the development of a planar distributed tactile display and the evaluation of the results of its effectiveness for displaying textures. The tactile display is composed of a 6 x 5 pin array actuated by 30 piezoelectric bimorphs. The distance between each pin&amp;amp;amp;apos;s centers is 1.8 mm. Vertical excursion of each pin is controlled over a 0-0.7 mm range. Perceptual experiments were conducted to evaluate the performance of the system under three conditions: active touc

Wearable tactile interfaces can enhance immersive experiences in virtual/augmented reality systems by adding tactile stimulation to the skin along with the visual and auditory information delivered to the user. We introduce a flat cone dielectric elastomer actuator (FCDEA) array that is thin, soft, and capable of producing spatiotemporally adjustable and large static-to-dynamic force in response to electric voltage signals on large areas of the skin. Integration of the FCDEA array into a photomi

In this work, we designed a haptic stylus interface interacting with a touch screen. The stylus has functions of providing vibration, impact, and sound and it is a stand-alone system including its own battery and wireless communication module. We present a new interaction scheme on the Windows graphical user interface based on haptic feedback events for clicking, drag & drop, moving, scrolling, highlighting, and other things. From conducting experiments, we evaluated its performance that the hap

In this work, we designed stylus type haptic interfaces interacting with a touch screen. There are two kinds of haptic styli termed wUbi-Pen. The type I has functions of providing vibration, impact, texture and sound and it is a stand alone system including own battery and wireless communication module. The type II does not include the texture display module and it is a miniaturized version. We present a new interaction scheme on the Windows graphical user interface based on pointer movement hap

Shape-morphing displays alter their surface geometry to convey information through three-dimensional shapes. However, rapid transformation into seamless shapes with multimodal tactile sensations poses challenges. Here, we introduce a versatile soft shape-morphing and tactile display, using a novel actuator that combines a PVC gel composite, dielectric liquid, and an electrode array. Proposed device facilitates on-demand liquid flow control through electrohydraulic actuation. Liquid channels with

The objective of this research is to propose and design a compact tactile display module and verify its performance in a pen-like haptic interface. A small, safe, silent and light tactile display module with a low power dissipation has been built. Based on this module, we present the Ubi-Pen, a system providing texture and vibration stimuli. Preliminary evaluations indicate it can satisfactorily represent tactile patterns. We also investigate the optimal frequencies at which to present stimuli,

This paper presents a novel haptic mouse that can be used as a human-computer interface and offers the capability of displaying properties such as patterns, gratings, and roughness. A small planar-distributed pin array is developed. Since the tactile display unit is small enough to be embedded into a computer mouse, we developed a texture display mouse. The performance of its texture display capability was verified. In addition, two psychophysical experiments have been conducted in order to asce

This paper presents a haptic stylus interface with a built-in compact tactile display module and an impact module as well as empirical studies on Braille, button, and texture display. We describe preliminary evaluations verifying the tactile display's performance indicating that it can satisfactorily represent Braille numbers for both the normal and the blind. In order to prove haptic feedback capability of the stylus, an experiment providing impact feedback mimicking the click of a button has b