Programs & Labs
Summer 2004
A safer way to multi-task
William Durfee
Can a single knob make your car safer? Professor William Durfee of the Department of Mechanical Engineering thinks the answer is yes. Durfee is currently conducting research on a new type of control interface that aims to reduce driver distraction by consolidating many non-critical control functions in one multi-purpose knob that behaves differently depending on how it is being used.
Driver distraction due to a complex control interface is becoming more problematic as car manufacturers add new electronic features for in-vehicle communication and navigation. One potential way to reduce the driver's cognitive load is to consolidate secondary controls into a single multi-function device while leaving controls for critical systems on the dashboard. In 2001, German automaker BMW introduced just such a system in its 700-series vehicles; dubbed "iDrive," it features a single large knob next to the brake lever and a computer-like monitor in the dashboard. Reaction to the system has been mixed, however, with many drivers finding that the interface is not intuitive.
Durfee's work aims to advance the multi-functional control concept by designing a knob that exhibits different "personalities" depending on the function it is performing. For example, the knob might present clicking detents when changing radio frequencies, but turn smoothly when adjusting temperature. A computerized servomotor system within the dashboard would emulate friction, resistance, and other sensations experienced when using a conventional knob.
In order to determine optimal haptic characteristics for different control functions, Durfee and his collaborators have constructed a unique experimental apparatus. It consists of an unassuming knob connected to a computer-controlled servomotor that emulates a variety of haptic feedback in real time, while a second computer provides auditory feedback, such as the "scratch" of friction or clicks as the knob turns. To create a more realistic testing environment, a video monitor in front of test subjects shows the knob as it would appear when installed in a control panel. The testing knob itself is mounted on a specially colored background, which a third computer digitally replaces with a virtual dashboard.
Results from the enclosure simulations will be used to incorporate a servomotor-controlled knob into the dashboard of a STISIM virtual driving simulator, enabling researchers to test the advantages of different feedback characteristics in a realistic driving environment. Durfee hopes this creative use of simulation technology will lead to a better driver interface for future cars, helping drivers keep their minds on the road.