Page:Advanced Automation for Space Missions.djvu/342

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CHAPTER 6

TECHNOLOGY ASSESSMENT OF ADVANCED AUTOMATION FOR SPACE MISSIONS

A principal goal of the summer study was to identify advanced automation technology needs for mission capabilities representative of desired NASA programs in the 2000-2010 time period. Six general classes of technology requirements derived during the mission definition phase of the study were identified as 'having maximum importance and urgency, including autonomous "world model" based information systems, learning and hypothesis formation, natural language and other man-machine communication, space manufacturing, teleoperators and robot systems, and computer science and technology. The general classes of requirements were individually assessed by attempting to answer the following sequence of questions in each case: (1) What is the current state of the relevant technology? (2) What are the specific technological goals to be achieved? (3) What developments are needed to achieve these goals? After the mission definition phase was completed, summer study personnel were reorganized into formal technology assessment teams with assignments based on interest and expertise. The results of this activity are summarized below.

6.1 Autonomous World Model Based Information Systems The first assessment team considered the technology necessary to autonomously map, manage, and re-instruct a world-model-based information system, a part of which is operating in space. This problem encompasses technology needs for a wide range of complex, computerized data systems that will be available twenty or thirty years hence. The concept of a world model aboard a satellite operating without human intervention appears useful for a variety of satellite missions, but is specifically required for the terrestrial applications IESIS (Intelligent Earth-Sensing Information System, see chapter 2) and Titan exploration (see chapter 3) missions defined during the summer study. The world model in space serves as a template by which to process sensor data into compact information of specific utility on Earth. It can consist of mapping data and modeling equations to describe, by past experience, the expected features the spacecraft will encounter. The use of the model requires algorithms in conjunction with the spacecraft sensors. A companion central model of higher sophistication will be required to further process, analyze, and disseminate the information and to update the entire world model. In the IESIS this component is on Earth and in the Titan mission it is centered around Titan, but in either case the entire system requires autonomous management. The following are some very general requirements for an autonomous world model-based information system; however, only the first two are discussed here. • Development of mission specific philosophy for handling the mission data • Model of the user and user requirements • Realistic mission simulation techniques to test mission designs • Modular satellite components • Satellite serviceable in space • Fault-tolerant design • Autonomous navigation assistance • Communications network • Autonomous pointing, navigation, and control • Standardized software to run and maintain satellites • Data return It is obvious that each NASA space mission should have specific information goals and that the data handling required in each must suit those goals. Costly data transmission and storage beyond that strictly required for mission operations should be eliminated. The sensor set adopted for a mission and its use must directly serve mission goals. The goals of the Titan mission differ widely from those of the intelligent Earth-sensing system. In comparison with Earth, Titan is basically unknown. The space exploration mission goal is generally to explore and to send back as much general information as possible to terrestrial researchers about Titan. The Earth is much better known, so a major IES1S goal is to return very specific information in response to user requests or system demands. (In this latter mission, raw pixel data should be returned only under very restricted circumstances. Users requiring raw data should pay a premium for it and should accept archiving responsibility as well.) Each mission will develop a uniquely relevant data-handling philosophy. This, of course, presupposes that models are available of mission users who are the final recipients of the data. PRECEDING PAGE BLANK NOT Ft,Lf_:SD