Abstract: A plurality of modular dual arch arrangements are aligned to provide the frame for a shelter. Each dual arch module constitutes first and second arches having their bases spaced from one another and leaning towards one another so that their crests rest against one another. The two arches are hinged to one another at their crests by a hinge. A fabric membrane is positioned over the arches and held in tension through various turnbuckles which attach the membrane to the bases which support the arches. A plurality of longitudinal fabric support bands are stretched longitudinally across the plurality of arches and held in tension to provide further support for the membrane.

Abstract: A collapsible, readily erectable shelter structure in the form of a pyramid having a plurality of fabric panels draped over and connected to a plurality of rigid columns. Each column is hinged at its top to a top plate and extends downwardly and outwardly to form the frame of the pyramidical structure. Each column is attached to a foot plate which rests on the ground. A central cable hangs down from the top plate and is adapted to be cinched to an item, such as a vehicle, that is being protected by the shelter. The central member is thereby placed under tension and the side columns are placed under compression. A plurality of tapes or webs or cables sewn to the panels are connected between adjacent side columns. When the structure is loaded, as by wind or snow, the foot plates tend to move outward and the tapes are placed under tension. The tapes resist the outward movement of the columns.

Abstract: A tailored membrane supported solely by a peripheral frame forms the front panel of a chamber. A source of vacuum or an air blower maintains a pressure in the chamber which differs from that of the ambient atmosphere. As a result, the tailored membrane is either drawn forward or pushed taut to provide a concave or convex viewing surface having a configuration determined solely by its tailoring.