Abstract
For design-support systems, the key framework is proposed to be available in various design phases in this paper. The framework is 'top-down' style from the rough design stages to the detailed design stages, and is called as 'Top-down Oriented Information Model'. This model is composed of four information model elements, 'entity', 'attribute', 'relationship', and 'constraint'. This top-down framework supports the design activities in the original meaning, because it enables us to define and handle product information with free and easy. Then the design support system is implemented based on the top-down framework. Some examples are shown that applies to initial design of the satellite.
