A Systematic Concept Exploration Methodology Applied to Venus In Situ Explorer

Abstract

A critical task in any design process is the initial conversion of customer or program objectives into a baseline system architecture. This task becomes particularly important for space exploration systems that have unique requirements which, in many cases, have never been met before. A useful tool to the space systems engineer would be a methodology which helps to make this objectives-to-design conversion more systematic and efficient. Presented in this paper is such a methodology frequently used at the Georgia Institute of Technology, and in this paper the methodology is applied to initial concept formulation for the Venus In Situ Explorer (VISE) mission. VISE is one of six New-Frontiers-class missions to occur within the next 30 years that NASA addresses in its Solar System Exploration Roadmap. VISE is envisioned as an aerial mission that will study Venus' atmospheric composition as well as descend briefly to the surface to acquire samples for later analysis at more benign altitudes. Common to both VISE and its successor, Venus Mobile Explorer, is the challenge to operate under the extreme temperatures (about 730 K) and pressures (about 90 atm) present at the Venusian surface. In order to establish a baseline mission and vehicle concept for VISE, the methodology presented here begins with problem definition and the generation of functional and operational architectures. Customer requirements and engineering targets are set through an established set of tools known as the seven management and planning tools and through the use of a quality function deployment (QFD). A morphological matrix is used to identify 12.4 billion potential solutions in the concept space. From this concept space, six representative designs are chosen to demonstrate how alternatives from the morphological matrix may be ranked through multi-attribute decision making (MADM) techniques such as the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) and Pugh concept selection matrices. Two of the six concepts are eliminated based on these MADM techniques, and the remaining four concepts are recognized as requiring more in-depth study to allow definitive rankings to be assigned. A notional modeling and simulation framework for this problem is formed which could be used to complete such an in-depth, quantitative study. This paper principally serves to illustrate an example of how a systematic objectives definition, concept generation, and downselection methodology can be applied to advanced interplanetary missions (specifically in the example of Venus In Situ Explorer). The methodology and tools presented here are shown as a helpful guide and addition to the toolbox of the space systems engineer during the advanced planning stages of design.