Research On Solid-surface Deployable Solar Concentrator

Solid-surface deployable solar concentrator is an innovative technology, aimed to harness solar energy in space for spacecraft. It is featured by high surface accuracy and high stiffness. On one hand, the concentrator can converge solar irradiation energy into a highly confined area, generating high density radiation energy. Thus, the capacity of the spacecraft to do work by solar energy shall be improved dramatically. The concentrator can be used for heat propulsion, orbit position adjustment and so on. In addition, the key to this technology is the deploying principles. The principles are identical to that of solid-surface deployable antennas, which are widely devised for earth resource exploration, military missions, Navigation and so on. To develop this technology, this thesis has completed the following work:Firstly, configuration and model design for the concentrator are conducted. A mechanism model is presented named Twin-Bennett linkage by introducing an overconstrained mechanism. Geometric constraint conditions for the mechanism are derived to prove its single Do F. Twin-Bennett linkage serves as a deployable unit. The approach to assemble n units around a regular polygon is presented and the assembly represents the schematic diagram of the concentrator. Kinematic properties are investigated about the assembly from both numerical and simulative perspectives.Secondly, parameter design is proposed to determine boundary equations of panels that make up the parabolic surface of the concentrator. The boundary equations are derived based on two methods: contour circle incision method, programming method. The former is to incise the parabolic surface and the latter is to depict the trajectory of panels in 3D space to analysis interference of the panels in rotational process.Thirdly, detailed structure design is presented, including hinge mechanism, transmission mechanism, and framework and so on. Kinematic analysis of combined mechanism with transmission mechanism and panels is presented. Kinematic parameters of the mechanism are derived.Finally, dynamic analysis of one unit driven by scroll springs is put forward. Dynamic model is built and kinetic equations are derived through Lagrange Equations. Meanwhile, this thesis demonstrates the deploying principles, parameter design results and mechanism design theories by manufacturing and assembling the concentrator. The manufacturing and assembling process is listed. Its folding and unfolding function is verified through experiment and the surface accuracy is measured. The peripheral surface accuracy is 0.1mm~0.2mm. The radius error rate is less than 5%.