Bistable Quad-Nets Composed of Four-Bar Linkages
This work addresses a domain-specific problem in mechanical engineering and discrete differential geometry, offering an incremental advance by applying known geometric techniques to bistable structures.
The paper tackles the problem of constructing bistable mechanical structures from spatial four-bar linkages, achieving a purely geometric method that enables control over axis positions and snap angles without numerical optimization.
We study mechanical structures composed of spatial four-bar linkages that are bistable, that is, they allow for two distinct configurations. They have an interpretation as quad nets in the Study quadric which can be used to prove existence of arbitrarily large structures of this type. We propose a purely geometric construction of such examples, starting from infinitesimally flexible quad nets in Euclidean space and applying Whiteley de-averaging. This point of view situates the problem within the broader framework of discrete differential geometry and enables the construction of bistable structures from well-known classes of quad nets, such as discrete minimal surfaces. The proposed construction does not rely on numerical optimization and allows control over axis positions and snap angles.