Frank Beruscha

An Evaluation of Input Controls for In-Car Interactions

The way drivers operate in-car systems is rapidly changing as traditional physical controls, such as buttons and dials, are being replaced by touchscreens and touch-sensing surfaces. This has the potential to increase driver distraction and error as controls may be harder to find and use. This paper presents an in-car, on the road driving study which examined three key types of input controls to investigate their effects: a physical dial, pressure-based input on a touch surface and touch input on a touchscreen. The physical dial and pressure-based input were also evaluated with and without haptic feedback. The study was conducted with users performing a list-based targeting task using the different controls while driving on public roads. Eye-gaze was recorded to measure distraction from the primary task of driving. The results showed that target accuracy was high across all input methods (greater than 94%). Pressure-based targeting was the slowest while directly tapping on the targets was the faster selection method. Pressure-based input also caused the largest number of glances towards to the touchscreen but the duration of each glance was shorter than directly touching the screen. Our study will enable designers to make more appropriate design choices for future in-car interactions.

An evaluation of the influence of haptic feedback on gaze behavior during in-car interaction with touch screens

A major motivation for the introduction of haptic feedback in in-vehicle touch screens is the reduction of the eyes-off-road time. This paper presents a study which compares different feedback conditions for touch screen interaction: (1) visual feedback, (2) combined visual-haptic feedback, and (3) haptic feedback only. Subjects had to select target buttons on a touch screen during simulated driving. Our results show that haptic feedback significantly reduces the eyes-off-road time and the subjectively perceived workload. When visual content is available, gazes on the touch screen are more frequent than necessary. And even in the absence of visual content, complete eyes-free interaction was only occasionally spotted, and subjects still looked at the screen initially. We assume that this is due to the necessity of an initial reference position.