Bistable dome array- using overlapping bistable domes to stiffen and control shape in thin strong materials.

Flex-actuated bistable domes can be used for sensing, controlling, and utilizing flexural forces in thin strong materials. Applications include:

Fig.1) Overlapping bistable dome array close-up. Metal dulled for scanning.

Note: the actual functional diameter of the overlapping domes is larger than what is suggested by the circular imprint caused by formation.

Fig.2-7) All photos below are of the same array of bistable domes.

An array of overlapping bistable domes forms an adjustable structure that is stiffer than the original flat metal and can’t be bent without causing domes to switch sides. The further it is bent the more domes will switch sides, locking in the new shape. It will stabilize in any shape within its local minimum radius limits. For any particular area, minimum (functional) radius limits are reached when all domes are oriented to one side or the other (Fig.2-3). Within a range, minimum radius limits can be manipulated by changing dome and dome material characteristics. The metal used in this array (.004” spring tempered stainless steel) can be bent past minimum convex and concave radius limits without permanent deformation.

The bistable domes used in this array are equally bistable. Unequally bistable domes have a predisposition for one side and can be used to give the overall structure a predisposition for a particular curvature or shape. Overlapping bistable dome structures, even a row of single domes, can be stiff enough to force a larger area of flat metal around them into a desired curvature.

Fig.2) Minimal functional radius- convex.

Fig.3) Minimum functional radius- concave.

Fig.4) S-curve.

Fig.5) S-curve close-up.

Fig.6) The overlapping bistable dome structure adds stiffness. Here the array is flattened somewhat and suspended horizontally by a single clip. Same area of original metal will droop.

Fig.7) The array can hold its shape along multiple radii simultaneously.

Back to:
  • Controlling springback and creating shape memory in thin high strength materials.

    See also:

    US Patent # 5563458. Apparatus and Method For Sensing Surface Flexure.
    US Patent # 6132187. Flex-actuated Bistable Dome Pump.