Touch Screen or iDrive?
The car is a lot more complicated electronic device than any iPod you can imagine. When you’re behind the steering wheel, there’s a lot of stuff on the menu: ventilation controls, audio entertainment options, navigation system, calibrations for the powertrain and chassis. It’s no wonder that car designers have been trying to figure out what to do about operating all this stuff.
Designers have long recognized that a simple touch-panel display possesses superior Human Machine Interface (HMI) qualities, yet they continue to seek a more elegant solution than the customary computer screen jammed in the middle of the dashboard. This is what led BMW to bring us iDrive in 2001, followed subsequently by Audi’s MMI and Mercedes-Benz’s COMAND. Now even Lexus is headed down this route to the remote-control device, replacing its widely admired touch-panel display with its Remote Touch interface for the 2010 Lexus RX.
Most people in the HMI field agree that the touch panel is better than any other type of control. That’s because the touch panel design is not only easy to use but also it has a very simple learning curve so the user can quickly master the interface.
Why then would many carmakers abandon this design in favor of remote-control devices that are meant to resemble a computer mouse, most of which have received less than stellar reviews due to compromises in usability? There are two reasons, and they’re both related to styling.
As we’ve noted, various performance, convenience, and advanced technology features are being added to vehicles every year. Also driver-customizable features and preference settings are becoming more common. To accommodate all of these new features and their adjustment, the standard solution would be to have a dedicated switch for each of them. But if there are countless switches scattered about the cabin, the driver soon gets the feeling that he’s in the cockpit of a Boeing 747 airliner. Integrating these switches into a single controller will minimize confusion and clean up the interior styling besides.
The other, more subtle motive for these controllers concerns the relationship of interior styling with the driver’s seating position. In order to have a touch panel design, the shape of the dash (known in engineering parlance as the instrument panel, or IP) must be somewhat high and close to the driver so the display screen is within his reach. Unfortunately the side effect is limited outward visibility and perhaps an intimation of claustrophobia. So the substitution of a controller for a touch panel display improves visibility and promotes an impression of interior spaciousness.
Most important, the deletion of the touch panel display gives designers some important flexibility in the layout of the whole IP. This is important because the reach the driver must make to activate certain controls is a hard-point in the design and engineering process, part of fixed human-factor values that relate to safety. Plus any display within the IP can then be optimized for an optimal focal distance from the driver as well as protection from glare.
So the next time your friend brags about the superiority of his iDrive controller over touch screen displays, you can respond with a straight face, “In some ways, perhaps.”
