Tactile display with rigid coupling based on soft actuator

Abstract

The tactile display is a device which physically stimulates the human skin to reproduce the feel of touch. This paper presents a novel tactile display device driven by a dielectric elastomer actuator. The device adopts an indirect actuation method by using a rigid coupling, which aims to avoid direct contact of the human skin with the actuator. The rigid coupling is made of silicone to transmit the movement of the actuator to the touch layer located on the top surface of the coupling and provides the feeling of softness on contact. The device produces displacement about 350-140 lm at 0.3-10 Hz, which meets frequency requirements for simulating the Merkel cells as well as Meissner corpuscle. The force to simulate the fingertips can be exerted over 44 mN. This work describes its design, analysis and fabrication method in details with its experimental evaluations.

Highly Transparent and Integrable Surface Texture Change Device for Localized Tactile Feedback

“…Peer‐reviewed reports mention the threshold displacement detection values as 30–100 µm for slow adapting receptors (Merkel cells) and 17 µm for fast adapting receptors (Meissner's corpuscles), which are distributed closer to the skin and contribute to the feel of touch. The deformations achieved by our device (up to 0.16 mm out‐of‐the plane deformations) are significant enough to be easily detected by fingers; as they are much higher than the threshold values for the spatial recognition by receptors in the fingertips . At higher applied electric fields, the Maxwell stresses are higher, consequently leading to higher shear strains and reduced thickness of active elastomer layer and electrical breakdown.…”

“…The blocked force measurement for the transparent electrode devices revealed a maximum of 47 mN at 21.4 V µm −1 and the force output reduced with lowering the applied electric field as shown in Figure d. These forces are large enough to be detected by the slow adapting and fast adapting receptors in our fingers . To measure the response time and frequency bandwidth of the device, blocked force was measured as a function of frequency at 21.4 V µm −1 .…”

“…DEAs have been investigated for applications in tactile and vibrotactile feedback devices via different approaches . Since the deformation produced in the active DEA layer can be small, appropriate coupling is required for out‐of‐plane deformation.…”

“…Hydrostatic coupling utilizing an incompressible fluid in conjunction with a DEA has been shown for refreshable braille displays . Coupling DEAs with rigid mechanical components allows for an amplification of fine deformations . Other approaches to “amplify” tactile feedback included coupling DEAs with vibrational simulation via variations in amplitude, frequency, or pulse‐time combinations .…”

Enhanced Design of a Soft Thin-Film Vibrotactile Actuator Based on PVC Gel

“…A new vibrotactile tactile module (ViviTouchTM) based on a non-ionic EAP was developed in order to convey realistic haptic sensation to game users [8]. Since the performance of the non-ionic EAP is influenced by the ratio of pre-stretching, a new mechanism for stretching the non-ionic EAP was addressed [9,10]. An arrayed tactile display with liquid coupling was presented using a non-ionic EAP [11].…”