Hasti Seifi

HapTurk: Crowdsourcing Affective Ratings of Vibrotactile Icons

Vibrotactile (VT) display is becoming a standard component of informative user experience, where notifications and feedback must convey information eyes-free. However, effective design is hindered by incomplete understanding of relevant perceptual qualities, together with the need for user feedback to be accessed in-situ. To access evaluation streamlining now common in visual design, we introduce proxy modalities as a way to crowdsource VT sensations by reliably communicating high-level features through a crowd-accessible channel. We investigate two proxy modalities to represent a high-fidelity tactor: a new VT visualization, and low-fidelity vibratory translations playable on commodity smartphones. We translated 10 high-fidelity vibrations into both modalities, and in two user studies found that both proxy modalities can communicate affective features, and are consistent when deployed remotely over Mechanical Turk. We analyze fit of features to modalities, and suggest future improvements.

VibViz: Organizing, visualizing and navigating vibration libraries

With haptics now common in consumer devices, diversity in tactile perception and aesthetic preferences confound haptic designers. End-user customization out of example sets is an obvious solution, but haptic collections are notoriously difficult to explore. This work addresses the provision of easy and highly navigable access to large, diverse sets of vibrotactile stimuli, on the premise that multiple access pathways facilitate discovery and engagement. We propose and examine five disparate organization schemes (taxonomies), describe how we created a 120-item library with diverse functional and affective characteristics, and present VibViz, an interactive tool for end-user library navigation and our own investigation of how different taxonomies can assist navigation. An exploratory user study with and of VibViz suggests that most users gravitate towards an organization based on sensory and emotional terms, but also exposes rich variations in their navigation patterns and insights into the basis of effective haptic library navigation.

Design of ultra-thin high frequency trilayer conducting polymer micro-actuators for tactile feedback interfaces

Fast actuation of conducting polymer trilayers has been achieved by reducing the thickness of the device to as little as 6 μm. Reducing size also reduces force and displacement. Here the tradeoffs between speed of response, force and deformation angle are explored, and related to an example application – a tactile feedback interface that aims to make use of the very high sensitivity of our fingertip skin to vibrations of about 150 Hz. In general, the actuation rate in these devices is limited by the speed of charging, and by inertia. Here we use an established transmission line model to simulate charging speed. By making use of the empirical relationship between strain and charge, and using beam bending theory, the extent of charging enables estimation of the degree of actuator deformation and the forces that can be generated. In seeking to achieve non-resonant actuation at frequencies of 150 Hz or more, while also generating the forces and displacements needed for tactile stimulation, it is found that electronic and ionic conductivities of the conducting polymer electrodes needs to be on the order of 24,000 S/m and 0.04 S/m, respectively. These values along with the required dimensions appear to be feasible.

Toward Affective Handles for Tuning Vibrations

When refining or personalizing a design, we count on being able to modify or move an element by changing its parameters rather than creating it anew in a different form or location—a standard utility in graphic and auditory authoring tools. Similarly, we need to tune vibrotactile sensations to fit new use cases, distinguish members of communicative icon sets, and personalize items. For tactile vibration display, however, we lack knowledge of the human perceptual mappings that must underlie such tools. Based on evidence that affective dimensions are a natural way to tune vibrations for practical purposes, we attempted to manipulate perception along three emotion dimensions (agitation, liveliness, and strangeness) using engineering parameters of hypothesized relevance. Results from two user studies show that an automatable algorithm can increase a vibration’s perceived agitation and liveliness to different degrees via signal energy, while increasing its discontinuity or randomness makes it more strange. These continuous mappings apply across diverse base vibrations; the extent of achievable emotion change varies. These results illustrate the potential for developing vibrotactile emotion controls as efficient tuning for designers and end-users.

[D69] End-user vibration customization tools: Parameters and examples

Summary form only given, as follows. Touch feedback (e.g., vibrations) can add to the expressiveness and utility of electronic devices, but users have a broad range of preferences as to their content and deployment. Rather than requiring of designers the nearly impossible task of pleasing everyone, we aim to empower users with easy-to-use tools that balance control with effort-of-use, for a desired degree of customizability. We focus in particular on affective qualities. In this demo, in the context of several application scenarios, we propose five parameters that can describe vibration customization tools, and demonstrate them with three tool concepts. Respectively, these follow themes of Choice (fast and convenient: choose individual stimuli), Filter (moderate control: modify base parameters of individual stimuli) and Block (high control: compose stimuli by arranging their component parts). Our aim is to open a discussion on end-user customization and tools, and learn of more contexts that could benefit from such an approach.