Car interiors go high-tech

A restaurant on the outskirts of Motor City once carved old car bodies into serviceable booths, allowing its patrons to relax on seats reclaimed from old Buicks while waitresses dressed as carhops took their orders.

In that alien environment, the car interiors took on a life of their own, becoming surrealistic exercises in brightly colored sheet metal, chrome, and imitation leather.

It was a sharp contrast to their mundane daily existence. Automotive interiors tend to blend into the background, as unnoticed as the lining of one's coat. Regardless, it is in the interior of an automobile where man meets machine , where he actually touches and controls it - in fact, where he lives with it.

To automotive designers, the interior is a marvel of complexity, from the maze of wiring behind the dash to the instrumentation, seating, interior lining, and lights.

Each piece must meet rigid safety regulations. Drivers demand comfort and ease of operation or they won't buy. Interiors bake in the sun, crack in the cold, and carry dogs with long toenails in the back seat.

Partly because of these design problems, automotive interiors tend to change infrequently. Pleated leather in the 1930s gave way to baroque, painted sheet metal during the '40s, leading to the rolling jukeboxes of the 1950s. Safety regulations in the '60s dictated padded dashboards and a web of seatbelts, ''crush space'' requirements, and head restraints - dominant themes that lasted through the '70s.

Today, car interiors are on the verge of a dramatic change.

''Most of the old stuff has been cast to the winds,'' says George E. Moon, General Motors executive in charge of interior design. ''It's because of the tremendous influx of electronics.''

High technology already is in evidence in automotive interiors. Liquid-crystal displays - the same as those used in wrist watches - are replacing such conventional instruments as speedometers in many cars. There have been several experiments in so-called ''trip computers,'' which calculate miles traveled on a tank of gas and average fuel economy.

But the true capabilities of the new electronics have scarcely been tapped, and ultimately they will change the actual shape of car interiors.

The reason is that the new electronic dashboard displays can be made much smaller than the traditional mechanical instruments they replace. Likewise, switches can be made much more compact, because they carry less current. This allows repositioning of the controls most commonly used.

''The idea is to move the controls to a position where they can be reached easily without removing the hands from the steering wheel,'' Mr. Moon says. Current plans at GM are to phase in the change between the 1985 and 1987 model years.

''If you want to see where we are going, look at the Buick Questor show car, '' suggests Mr. Moon. The Questor features advanced electronics that seriously interest GM officials, including a steering-wheel-mounted control cluster.

Development of new technology also means some exotic gizmos are being added to the family bus.

Ford, in fact, plans to introduce soon a limited-production run of a computer-controlled cathode-ray tube. It's actually a miniature version of a home television screen, but with the ability to display virtually any combination of graphics or information.

Cathode-ray tubes (CRTs) also are in the experimental stages at GM and Japan's Honda Motor Company. Honda has even tied its CRT to a navigation system that displays a map with a moving dot indicating the car's location.

Electronics, particularly when coupled to digital dashboard displays, yields what stylists are calling the high-tech look - a kind of Spartan appearance that seems reminiscent of a piece of stereo equipment. That's no accident, according to Mr. Moon, who says he actually goes to electronic-equipment shows for inspiration.

Even so, his enthusiasm isn't shared by all. ''Personally, I prefer conventional gauges on sporty cars,'' asserts John Schinella, chief stylist at Pontiac, whose last creation was the sporty Trans Am.

Developments in so-called ''molded shell'' seating and door panels mean cars of the future are likely to have thinner, more contoured interiors. That means more usable interior space and a lighter, cleaner appearance.

Another noticeable trend, where manufacturers in the United States have lagged behind the imports, is the development of more sophisticated seating to provide proper body support.

The study of the human body and its structural needs is part of the science of ergonomics. Studies done in the early 1960s showed that most car seats lacked sufficient lower-back support to be comfortable on long trips. Several European cars adopted ergonomically designed seats, but US designers stuck with the overstuffed look that felt good at first touch.

That, too, is changing. Bucket seats with multiple adjustments - including hip, lower back, and under-thigh support - are offered as options on GM, Ford, and Chrysler products in the 1983 model year. Volkswagen likewise upgraded its ' 83-model seats as part of an overall redesign of the current-model Rabbit.

All of this is evidence that function is gaining at least some ground in the interior design of automobiles.