Historic Information - Door Design
The doors operate just like in the Back to the Future movies with a couple exceptions. First, (when in good condition) they open better than indicated in the movies (you may notice in the movies that the doors often "droop" and Michael J. Fox keeps hitting his head). Second, they make no metallic motorized sound when opening or closing.
These style doors are popularly referred to as "gullwing" doors and were popularized by a classic Mercedes sports coupe. The Bricklin also used doors of this style but relied on pneumatic actuators to "pump" the doors up when a button was pressed. These doors are different than the Lamborghini doors (popularly called jack-knife doors) which swing forward on a hinge rather than upward.
The doors are couterbalanced by a cryogenically manufactured torsion bar designed and built by Grumman Aerospace in Long Island, NY. These are assisted by the door struts. The doors are maintenance free (except replacing the struts on occasion and a rare torsion bar adjustment).
Contrary to popular belief, the doors do not swing out very much and no extra room is required in order to operate them. They are hinged fairly close to the centerline of the roof and thus primarily swing upward. Only 12" of clearance is required to operate the doors and the car is easier to get in and out of in tight spaces than most conventional cars.