Method to optimize the environmental test level of various space hardware and mission from a viewpoint of minimizing total cost

Abstract

Environmental test for space hardware is one of the effective way to verify their design and quality. The level of environmental test has been decided empirically based on the development experience of government procurement large satellite of each space agency. However, this test level may not necessarily be the optimal solution in some cases due to diversification of missions and spacecraft design in recent years. In order to solve this problem, we propose a new model which optimizes the environmental test level from the viewpoint of minimizing the total costs related to the environmental test: replacement or repair cost due to failure in the test and the loss cost due to failure in the flight environment. By using this model, it is possible to find the optimum test level according to the importance of a mission, single mission or multiple missions applied hardware. Furthermore, the proposed method will support the quantify assessment of the cost reduction effects when either increasing design margin or reducing strength variation in production.

Keywords

• test effectiveness
• environmental test
• stress - strength
• normal distribution
• total cost