Pages: pp. 4-5
The number of daily human computer interactions with consumer devices is increasing at a staggering rate. Just considering text messaging in the United States alone, more than a trillion text messages have been sent in the last year (CTIA Semi-Annual survey October 2011). The fundamental means of interacting with our digital environment are through video, audio, and haptics, and the sense of touch is paramount in how we enter information into the device. As a result, haptics in consumer electronics has been a topic of growing importance in the publications of not only the haptics community, but also those of the IEEE Consumer Electronics Society. For two years now, the International Conference on Consumer Electronics (ICCE) has adopted haptics to the tracks on human computer interfaces. This resulted in a joint call for papers for both the journal and the ICCE, leading to this special section.
Touch screens are the predominant interface today, and are driving consumer haptic adoption. Given the immense number of interactions with digital devices, it is critical to make those interactions intuitive and natural to use, and to maximize the channels available to us for interaction, such as using haptics in different ways to convey information back to the user. Both of these areas will be addressed by the five papers in this special section.
The first generations of haptic-enabled consumer devices, and the majority on the market today, have been primarily based on electromagnetic motors that create whole device vibration. This, however, is only the beginning when considering the range of haptic experiences that are possible. High fidelity haptics, using piezo actuators and electroactive polymers, are currently being launched in the market and will be an important step in advancing the user experience by taking advantage of the broader range of experiences that can be rendered. Future devices will go beyond even that by providing directional cues via vibrotactile travelling waves, creating the feel of real world textures, and enabling new haptic experiences such as skin stretch, variable friction, or even small or large scale deformation.
One of the keys to widespread commercial success of haptics in consumer devices is in developing the entire ecosystem for this multidisciplinary field. This includes making advancements in the understanding of human haptic perception, the base enabling technologie such as actuators, amplifiers, and rendering methods, as well as the software development and design tools, all culminating in the way that haptics is used in the end application. The first four papers in this special section are directed at the base enabling technologies such as electrotactile displays, vibrotactile travelling waves, and providing multimodal direction cues for mobile devices, while the last paper focuses on how haptics is used in the interface.
The first paper, “Electrotactile Feedback for Handheld Devices with Touch Screen and Simulation of Roughness," by M. Ercan Altinsoy and Sebastian Merchel, introduces a novel electrotactile display integrated into a mobile device touchscreen. They apply the technology to rendering of virtual textures on the touchscreen and demonstrate that the electrotactile display is capable of controlling the perceived roughness of textures via two psychophysical experiments. This work expands the benefits of the electrotactile display that has some integration advantages over the more common vibrotactile approach.
The next two papers have a common theme, a vibrotactile flow (or wave), that can be produced by two vibrotactile actuators to deliver the sensation of a moving vibration on a plane. The second paper, “Vibrotactile Rendering for a Traveling Vibrotactile Wave Based on a Haptic Processor,” by Sang-Youn Kim and Jeong Cheol Kim, is particularly relevant to this special section as they present an electronic chip that includes the function of vibrotactile wave generation and is ready for adoption in consumer mobile devices. The third paper, “Smooth Vibrotactile Flow Generation Using Two Piezoelectric Actuators,” by Jeonggoo Kang, Jongsuh Lee, Heewon Kim, Kwangsu Cho, Semyung Wang, and Jeha Ryu, advances the technology for vibrotactile waves by using two wideband piezoelectric actuators. They propose a frequency-sweeping algorithm that can modulate the resonance position on a plate and demonstrate that the algorithm can improve the quality of vibrotactile flow perception. These two papers further elevate the possibility of using the vibrotactile flow technology in commercial handheld devices.
In the fourth paper, “Mobile Navigation Using Haptic, Audio, and Visual Direction Cues with a Handheld Test Platform,” Rebecca L. Koslover, Brian T. Gleeson, Joshua T. de Bever, and William R. Provancher develop a multimodal handheld display as a navigation aid. The display can provide visual, auditory, vibrotactile, and skin-stretch stimuli, and its performance is evaluated under both stationary and mobile situations. In particular, this work provides the performance of each modality in terms of response time, which can be valuable knowledge for the engineers who design mobile navigation devices or applications.
Last, “Negative Feedback for Small Capacitive Touchscreen Interfaces: A Usability Study for Data Entry Tasks,” by Sarangi P. Parikh and Joel M. Esposito, examines the advantages and disadvantages of negative feedback for a key-entry task on the touchscreen. While in conventional interfaces, positive feedback (e.g., confirmation of correct key presses) is more popular, negative feedback (e.g., feedback of erroneous or ambiguous key presses) also provides end user value. The strong aspects of this study lie on careful, objective comparisons of the pros and cons of the negative feedback approach.