Development of a Decision Support System for Incorporating Risk Assessments during the System Design of Microsatellites

The primary purpose of this research is to develop a decision support system for the early design of an optimal and reliable satellite while making the overall conceptual design process more efficient. Generally, a satellite design process begins with a mission definition followed by the functional design of the satellite system. Beyond this, the design goes through several iterations and eventually results in a detailed satellite system design. Only then does it make sense to feed in the piece-part information to estimate the reliability of the entire satellite system. Predicted reliability from this bottom-up method may sometimes be markedly lower than the requirements. In such case, the maturity of the design is brought down, and mitigation strategies need to be implemented to meet the reliability requirements. Consequently, introducing new or redundant parts as a mitigation approach can violate the previously satisfied requirements such as mass, power and cost. Furthermore, additional design iterations are needed until all the requirements are met. Therefore, this design approach is expensive, inefficient, and can be avoided if reliability is considered from the early design phase. However, the challenge is to simultaneously perform reliability analysis and system design as they are entirely different engineering disciplines. In this research, a decision support system: DESIRA is developed to bridge the gap between these two engineering disciplines and incorporate reliability assessments during the early design phase, thus resulting in a truly optimal satellite design. With its unique features such as Reliability Allocation, Reliability Growth, Multidisciplinary Design Optimization and Reliability-Based Multidisciplinary Design Optimization, DESIRA effectively aids the system design at each maturity level.