One of the most important issues in space structure designs is to reduce total weight of the structure. Structural size of a solar cell paddle for spacecraft becomes large corresponding to increasing electric power requirements for future advanced missions. Lightweight structures can be adopted for many space applications considering growing requirements of future missions. In the design of solar array paddles deployable structure has a large percentage of the total weight. In the deployment mechanism, using components with low rigidity and lightweight may reduce the total weight. Then we should consider influence of the deployment mechanism on structural characteristics. We performed structural analysis and experiment to clarify the dependence of the dimension and the configuration of deployment mechanism. As a result, we found that the influence on the vibration characteristics of the deployment mechanism like a hinge disposed between the panels against large structure is small and in particular the influence of the bending stiffness in the vertical direction of the panel surface is large. We found that it becomes possible to lightweight by obtaining optimum design parameters such as the Young's modulus and the cross-sectional area of deployment mechanism corresponding to the scale of structure.
