Abstract: Lenticular boom is used as the main supporting rod of the thin-film solar array of space solar power station. The envelope volume and weight of active driving mechanism commonly used to control the deployment of the boom are relatively large. The control approach of boom deployment is a decisive factor of the storage ratio, which can significantly reduce the envelope volume and weight of the solar array through optimization. It is regarded as a promising method for establishing the ultra-large and light-weight space solar power station. In view of this, the passive deployment of composite thin-walled lenticular boom (CTLB) with full utilization of the elastic recovery characteristics of its cross-section is investigated in this paper. With the explicit dynamics finite element (FE) method, the mechanical responses of CTLB during flattening and coiling are analyzed in terms of the elastic stress and strain. Then the peel force of the flexible fastener during detachment is numerically obtained. The flexible fastener is chosen as the control unit for CTLB deployment. By inheriting the deformed shape and material state from the proceeding FE analysis and simulating the flexible fastener using cohesive element, a dynamic model is established for the deployment of CTLB. Then the influence of the mechanical properties of flexible fasteners on the unfolding characteristic of CTLB is numerically studied. The results show that the orderly deployment of CTLB can be achieved by adjusting the detachment force of flexible fastener, which provides a solution for further reducing the complexity and weight as well as improving the storage ratio of ultra-large thin-film solar array.

Key words:  , space solar power station, thin-film solar array, lenticular boom, elastic energy-powered passive deployment, deployment dynamics