One-DOF hexagonal thick-panel origami with uniform thickness, flat deployable surface and compact folding

Thick-panel origami considers the panel thickness for engineering requirements such as solar arrays and reflectarray antennas. However, it is still a challenge to generate the flat surface for two-dimensional deployable structures based on thick-panel origami. In this paper, a construction method for a family of one-degree-of-freedom (one-DOF) folding assemblies with uniform thickness, flat deployable surface and compact folding is proposed based on hexagonal thick panels. Taking the spatial 8R linkage as the kinematic model of thick-panel unit, the one-DOF mechanism networks of 8R linkages are investigated to create hexagon-based folding assemblies with kinematic compatibility and folding capability. Through flipping transformations and various connection forms, a total of sixteen cases of folding assemblies and their one-DOF mechanism topologies are developed to present flat deployable surfaces and compactly folded advantages. Furthermore, the surface integrality of folding assemblies is presented without physical interference, and the prototype is fabricated to verify kinematic properties. The newly found design strategy and construction method can be readily extended to other polygon-based assemblies with potential applications such as deployable structures for aerospace exploration and architecture.