Rendering Softness: Integration of Kinesthetic and Cutaneous Information in a Haptic Device.
ABSTRACT While it is known that softness discrimination relies on both kinesthetic and cutaneous information, relatively little work has been done on the realization of haptic devices replicating the two cues in an integrated and effective way. In this paper, we first discuss the ambiguities that arise in unimodal touch, and provide a simple intuitive explanation in terms of basic contact mechanics. With this as a motivation, we discuss the implementation and control of an integrated device, where a conventional kinesthetic haptic display is combined with a cutaneous softness display. We investigate the effectiveness of the integrated display via a number of psychophysical tests and compare the subjective perception of softness with that obtained by direct touch on physical objects. Results show that the subjects interacting with the integrated haptic display are able to discriminate softness better than with either a purely kinesthetic or a purely cutaneous display.
SourceAvailable from: Shogo Okamoto[Show abstract] [Hide abstract]
ABSTRACT: In daily life, certain textures and materials invite our touch motions. To seek the nature of such haptic invitation, we conducted a series of experiments consisting of sensory evaluations and ranking tasks for 36 materials to ascertain their perceptual properties and their degrees of haptic invitation. In addition, we recorded the human touch motions elicited by these materials. The results showed high degrees of haptic invitation for materials with perceptually prominent textures, which indicates that such textures frequently invite human touch motions. We also developed a Bayesian network model that represented the probabilistic relationships between invited touch motions and the properties of textures. The model substantiated the observation that different types of textural prominence led to different types of invited touch motions. These results collectively suggest that materials with prominent textures frequently encourage humans to touch them, using appropriate or specified touch motions.IEEE Transactions on Haptics 05/2014; 7(3):345-355. DOI:10.1109/TOH.2014.2321575 · 2.03 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: In this paper, we present a haptic feedback method for a virtual button based on the force-displacement curves of a physical button. The original feature of the proposed method is that it provides haptic feedback, not only for the "click" sensation but also for the moving sensation before and after transition points in a force-displacement curve. The haptic feedback is by vibrotactile stimulations only and does not require a force feedback mechanism. We conducted user experiments to show that the resultant haptic feedback is realistic and distinctive. Participants were able to distinguish among six different virtual buttons, with 94.1% accuracy even in a noisy environment. In addition, participants were able to associate four virtual buttons with their physical counterparts, with a correct answer rate of 79.2%.Proceedings of the 26th annual ACM symposium on User interface software and technology; 10/2013
[Show abstract] [Hide abstract]
ABSTRACT: We describe here a wearable, wireless, compact, and lightweight tactile display, able to mechanically stimulate the fingertip of users, so as to simulate contact with soft bodies in virtual environments. The device was based on dielectric elastomer actuators, as high-performance electromechanically active polymers. The actuator was arranged at the user's fingertip, integrated within a plastic case, which also hosted a compact high-voltage circuitry. A custom-made wireless control unit was arranged on the forearm and connected to the display via low-voltage leads. We present the structure of the device and a characterization of it, in terms of electromechanical response and stress relaxation. Furthermore, we present results of a psychophysical test aimed at assessing the ability of the system to generate different levels of force that can be perceived by users.Frontiers in Bioengineering and Biotechnology 09/2014; 2:31. DOI:10.3389/fbioe.2014.00031