Structural Architectures for a Deployable Wideband UHF Antenna

Abstract

This paper explores concepts for a wideband deployable antenna suitable for small satellites. The general approach taken was to closely couple antenna theory and structural mechanics, to produce a deployable antenna that is considered efficient in both fields. Approaches that can be deployed using stored elastic strain energy have been favored over those that require powered actuators or environmental effects to enforce deployment. Two types of concepts were developed: thin shell structure and pantograph. These concepts cover four antenna topologies: crossed log periodic, conical log spiral, helical and quadrifilar helix. Of these, the conical log spiral antenna and the accompanying deployment concepts are determined to be the most promising approaches that warrant further study.

Deployable helical antennas for cubesats

“…This paper has reviewed the helical pantograph concept originally presented in [10]. Insights into the helical pantograph structure have been obtained from analytical solutions for helical rods and from finite element simulations of an eight-helix structure matching the dimensions of a physical prototype that has built and tested.…”

“…Hence, the structure has the potential to deploy by releasing its stored strain energy, rather than relying on deployment systems that provide external energy, such as cables or motors. A detailed description of this concept and its development are presented in [10].…”

“…The torsion of the helix is (8) The bending and twisting moments in the initially straight rod are then (9) while the internal force, assuming no stretch in the helix, is (10) and both are uniform along the entire rod. In the above equations, α is the helix angle, E is the elastic modulus, G is the shear modulus, I is the vertical cross section second moment of area and J is the torsion constant.…”

“…The present paper focuses on further study of the helical pantograph structure from [10]. The helical pantograph is a new structural concept and hence our objective is to understand and explain its behavior.…”

“…In [10], four structural concepts suitable for packaging UHF antennas on small satellites with limited pointing control were proposed. The present paper focuses on further study of the helical pantograph structure from [10].…”