The proposed balloon experiment for deploying large-sized membrane, which is intended to be shown in this paper, is postponed to September, 2008. We are now designing a new structure and mechanism of a spacecraft which is to be validated at the balloon experiment. We proposed "Multi-step deployment" of membrane in this paper, which reduces the risk of complexity of the deploying system compared to conventional system. In addition, we analyzed the feasibility of attitude control required for orbital maneuver with conventional chemical thruster and positively solved. The amount of propellant is also calculated and found to be feasible. The system we discussed in this paper is to be equipped with a newly designed spacecraft planned in 2010s. Copyright IAF/IAA. All rights reserved.