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Mobile sign language video communication has the potential to be more accessible and affordable if the current recommended video transmission standard of 25 frames per second at 100 kilobits per second (kbps) as prescribed in the International Telecommunication Standardization Sector (ITU-T) Q.26/16 were relaxed. To investigate sign language video intelligibility at lower settings, we conducted a laboratory study, where fluent ASL signers in pairs held real-time free-form conversations over an experimental smartphone app transmitting real-time video at 5 fps/25 kbps, 10 fps/50 kbps, 15 fps/75 kbps, and 30 fps/150 kbps, settings well below the ITU-T standard that save both bandwidth and battery life. The aim of the laboratory study was to investigate how fluent ASL signers adapt to the lower video transmission rates, and to identify a lower threshold at which intelligible real-time conversations could be held. We gathered both subjective and objective measures from participants and calculated battery life drain. As expected, reducing the frame rate/bit rate monotonically extended the battery life. We discovered all participants were successful in holding intelligible conversations across all frame rates/bit rates. Participants did perceive the lower quality of video transmitted at 5 fps/25 kbps and felt that they were signing more slowly to compensate; however, participants' rate of fingerspelling did not actually decrease. This and other findings support our recommendation that intelligible mobile sign language conversations can occur at frame rates as low as 10 fps/50 kbps while optimizing resource consumption, video intelligibility, and user preferences.

Eye-typing performance results are reported from controlled studies comparing an on-screen keyboard and Eye Write, a new on-screen gestural input alternative. Results from the first pilot study suggest the presence of a learning curve that novice users must overcome in order to gain proficiency in EyeWrite's use (requiring practice with its letter-like gestural alphabet). Results from the second longitudinal study indicate that EyeWrite's inherent multi-saccade handicap (4.52 saccades per character, frequency-weighted average) is sufficient for the on-screen keyboard to edge out Eye Write in speed performance. Eye-typing speeds with Eye Write approach 5 wpm on average (8 wpm attainable by proficient users), whereas keyboard users achieve about 7 wpm on average (in line with previous results). However, Eye Write users leave significantly fewer uncorrected errors in the final text, with no significant difference in the number of errors corrected during entry, indicating a speed-accuracy trade-off. Subjective results indicate that participants consider Eye Write significantly faster, easier to use, and prone to cause less ocular fatigue than the on-screen keyboard. In addition, Eye-Write consumes much less screen real-estate than an on-screen keyboard, giving it practical advantages for eye-based text entry.

The increasing quantity and complexity of in-vehicle systems creates a demand for user interfaces which are suited to driving. The steering wheel is a common location for the placement of buttons to control navigation, entertainment, and environmental systems, but what about a small touchpad? To investigate this question, we embedded a Synaptics StampPad in a computer game steering wheel and evaluated seven methods for selecting from a list of over 3000 street names. Selection speed was measured while stationary and while driving a simulator. Results show that the EdgeWrite gestural text entry method is about 20% to 50% faster than selection-based text entry or direct list-selection methods. They also show that methods with slower selection speeds generally resulted in faster driving speeds. However, with EdgeWrite, participants were able to maintain their speed and avoid incidents while selecting and driving at the same time. Although an obvious choice for constrained input, on-screen keyboards generally performed quite poorly.

People with motor impairments often cannot use a keyboard or a mouse. Our previous work showed that a handheld device, connected to a PC, could be effective for computer access for some people with motor impairments. But text entry was slow, and the popular unistroke methods like Graffiti proved difficult for some people with motor control problems. We are now investigating how physical edges can provide stability for stylus gestures, and we are designing a unistroke alphabet whose letter-forms are defined along the edges of a small plastic square hole. This paper presents data on the benefits of physical edges in making gestures. It then describes EdgeWrite, a new unistroke alphabet designed to leverage physical edges for greater stability in text entry.

Though exciting scientifically, autonomous agent design can result in legal liability. This paper surveys those legal concerns, focusing on issues arising from the unique qualities of agents not found in conventional software. Informed designers can more effectively reduce their liability exposure and influence emerging agent liability law and policies.