Touchscreen input in commercial aircraft cockpits offers potential advantages, including ease of use, modifiability, and reduced weight. However, tolerance to turbulence is a challenge for their deployment. To better understand the impact of turbulence on cockpit input methods we conducted a comparative study of user performance with three input methods -- touch, trackball (as currently used in commercial aircraft), and a touchscreen stencil overlay designed to assist finger stabilization. These input methods were compared across a variety of interactive tasks and at three levels of simulated turbulence (none, low, and high). Results showed that performance degrades and subjective workload increases as vibration increases. Touch-based interaction was faster than the trackball when precision requirements were low (at all vibrations), but it was slower and less accurate for more precise pointing, particularly at high vibrations. The stencil did not improve touch selection times, although it did reduce errors on small targets at high vibrations, but only when finger lift-off errors had been eliminated by a timeout. Our work provides new information on the types of tasks affected by turbulence and the input mechanisms that perform best under different levels of vibration.

By exploiting visual popout effects, interface designers can rapidly draw a user's attention to salient information objects in a display. A variety of different visual stimuli can be used to achieve popout effects, including color, shape, size, motion, luminance, and flashing. However, there is a lack of understanding about how accurately different intensities of these effects support popout, particularly as targets move further from the center of the visual field. We therefore conducted a study to examine the accuracy of popout target identification using different visual variables, each at five different levels of intensity, and at a wide range of angles from the display center. Results show that motion is a strong popout stimulus, even at low intensities and wide angles. Identification accuracy decreases rapidly across visual angle with other popout stimuli, particularly with shape and color. The findings have relevance to a wide variety of applications, particularly as multi-display desktop environments increase in size and visual extent.

Awareness information in shared-workspace groupware is often ephemeral, and when users are interrupted or look away from the system, they can miss important information about others' activities. These attentional disconnections are brief (generally less than ten seconds), are frequent in many work environments, and can occur for many reasons. In this paper, we provide visualization techniques that can help groupware users recover from these short absences. First, we provide a simple attention monitor that informs groupware systems whether a user is looking at the screen and whether the workspace is visible. Second, we provide a framework of catch-up techniques for visualizing missed activity -- including highlighting, motion traces, and replay. We implemented these techniques in three applications that cover different communication methods and interaction speeds, and explored the use of the effects in three studies. Participants clearly saw the value of catch-up techniques, and although different techniques were preferred in different situations, nearly all users strongly preferred the catch-up techniques. Our work shows that helping users deal with periods of attentional disconnection can substantially improve the usability of real-time groupware systems.