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Fig 1. Typical cross-section of proposed bi-stable beam
spool. The deployment, controllable or not, is performed by unreeling the
beam from the spool. Another utilization of bi-stable structures is a tape-
spring based hinges, one or several thin metallic curved strips connecting
two hinged parts [3].
2. Design and experiments.
The deployable space construction design
possibly appropriate for reflector is presented in this paper. Such design
allows retaining the advantages of space truss reflector while reducing its
complexity and price. The proposed solution is a space truss, formed by bi-
stable beams with closed cross-section, which can be flatten by pressing the
beam with compression forces in cross-section symmetry plane. Rigidness
of flattened beam reduces significantly, leading to the formation of so called
“dynamic” hinge in structure. Structure with such a set of “dynamic” hinges
can be folded just like the one with mechanical hinges. The cross-section
of bi-stable beam is schematically shown in Fig. 1, typical space truss
elements are shown in Fig. 2.
The bottom surface of observed cross-section was made flat in order to
couple it with textile reflector and could be made curved to fit the required
geometrical form.
Fig 2. Typical triangle and hexagonal space truss elements formed of bi-stable beams
ISSN 0236-3941. Вестник МГТУ им. Н.Э. Баумана. Сер. “Машиностроение” 2015. № 1 51