The Jet Propulsion Laboratory (JPL) is developing the All-Terrain Hex-Limbed Extra-Terrestrial Explorer (ATHLETE) as part of NASA's Exploration Systems Mission Directorate, Exploration Technology Development Program (ETDP). The program develops technologies for surface mobility and equipment handling, human-system interaction, and lunar surface system repair, and constructs dexterous robots and autonomous rovers that can drive over rough terrain and help crew explore, assemble, and maintain a lunar outpost. ETDP sponsors a series of field tests at lunar analog test sites where prototype robots can operate in ways that simulate lunar surface conditions. In this paper, we describe the lessons learned about ATHLETE operations at the most recent lunar analog field test in June 2008 at Moses Lake Sand Dunes, Washington. The Moses Lake field test was structured as a series of "acts" which correspond to unpiloted and piloted missions to the lunar surface in the 2019 to 2022 timeframe. The field test took place over a period of two weeks and involved several robots from various NASA field centers, including the Chariot lunar truck from Johnson Space Center, the K10 planetary rover from Ames Research Center, and ATHLETE from JPL. Lessons learned from the Moses Lake field test will be incorporated into the evolving design of the ATHLETE operations system, and will be tested at subsequent field trials.

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The size and complexity of mission control software, both flight and ground, has increased rapidly over the last ten years. The fact that such software controls virtually all flight activities, and that failures attributed to software often have roots in systems engineering, has led to recognition of the need for a closer coupling between systems engineering and software engineering. Because of this, there has been an increasing amount of work devoted to developing new approaches to systems engineering for model-based control and operations system design. One such approach is State Analysis.State Analysis is a structured methodology for analysis of control problems that emphasizes state variables and behavior models. It strives to unify systems and software engineering disciplines into a common set of vocabulary, procedures, and tools, utilizing common framework software to achieve a very direct realization of analysis artifacts into code. This paper examines the practical application of State Analysis by following the full development cycle of a prototype monitor and control system targeting NASA's proposed array-based Deep Space Network (DSN), from initial state analysis through goal-based operations design, translation of systems engineering specifications into a software design, and finally implementation of the design through the adaptation of the software framework. The synergy between systems and software engineering is highlighted through concrete examples of reusable software design patterns that map directly to systems engineering artifacts, including mechanisms for goalbased fault tolerance. The paper also describes lessons learned from the application of the process and design patterns.