Developing Decision Aids to Enable Human Spaceflight Autonomy

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Developing Decision Aids to Enable Human Spaceflight Autonomy Articles Developing Decision Aids to Enable Human Spaceflight Autonomy Jeremy D. Frank, Kerry McGuire, Haifa R. Moses, Jerri Stephenson n As NASA explores destinations istorically, NASA’s crewed missions have been limited beyond the moon, the distance between to the Earth-moon system or low Earth orbit (LEO). Earth and spacecraft will increase com - HClose proximity to Earth allows instantaneous com - munication delays between astronauts munications between NASA’s Mission Control Center (MCC) and the Mission Control Center (MCC). and astronauts on board the spacecraft. As NASA prepares for Today, astronauts coordinate with MCC to request assistance and await missions beyond the moon, including missions to Mars (the approval to perform tasks. Many of Evolvable Mars Campaign), the distance from the spacecraft these coordination tasks require multi - to Earth will result in long communication delays. Table 1 ple exchanges of information, (for shows the one-way light-time delay between Earth and some example, taking turns). In the presence future mission destinations (Frank et al. 2015). of long communication delays, the Currently, astronauts on board the International Space Sta - length of time between turns may lead tion (ISS) depend upon the Earth-based Mission Control Cen - to inefficiency or increased mission risk. ter for technical assistance, troubleshooting, and daily sched - Future astronauts will need software- based decision aids to enable them to ule updates. If a piece of equipment fails on the ISS, MCC will work autonomously from the Mission be notified by the crew or by the data being streamed to the Control Center. These tools require the ground. MCC uses this information to evaluate the failure appropriate combination of mission and decide how to fix the problem. Once a plan of action is operations functions, for example, auto - determined, MCC provides instructions to the crew. This mated planning and fault manage - concept of operations is not sustainable for a crew at Mars; ment, troubleshooting recommenda - even simple problems may take minutes, or even hours, to tions, easy-to-access information, and just-in-time training. Ensuring that resolve, due to the time delays shown in table 1. In order to these elements are properly designed and integrated requires an integrated human factors approach. This article describes a recent demonstration of autonomous mission operations using a novel software-based decision aid on board the International Space Station. We describe how this new technology changes the way astronauts coordinate with MCC, and how the lessons learned from these early demonstrations will enable the operational autonomy need - ed to ensure astronauts can safely jour - ney to Mars, and beyond. 46 AI MAGAZINE Copyright © 2016, Association for the Advancement of Artificial Intelligence. All rights reserved. ISSN 0738-4602 Articles Destination Distance (kilometers) One-Way Time Delay (minutes) ISS 435 Lunar 38,400,000 0.02 Mars (close) 545,000,000 3 Mars (opposition) 4,013,000,000 22.3 Table 1. One-Way Time Delay Between Earth and Future Mission Destinations. resolve this issue, astronauts will need to be recovery of piloted aircraft (Klyde et al. 2014). While autonomous, or operationally independent, from the future human exploration of space will include high - Mission Control Center. Future crews will need the ly dynamic piloting tasks, even seemingly mundane capability to evaluate system health independently living and working tasks (for example, maintenance, and respond to failures. Doing so requires the ability repairs, science operations) require significant assis - to monitor system and vehicle health, troubleshoot tance from MCC, and can benefit from decision aids issues, and maintain their daily schedules, all with - that enable astronaut autonomy. out relying on MCC. A higher degree of crew auton - A number of crew autonomy demonstrations have omy represents a fundamental change to mission been performed in space, on board the ISS. These operations. Enabling this new operations philosophy include crew autonomous procedures (astronauts requires a host of operations protocol and technolo - performed numerous human spaceflight procedures gy development. without assistance from MCC, resulting in guidelines on the writing of these procedures [Beisert et al. 2013]); procedure automation (automating proce - Decision Aids to Enable Autonomy dures normally performed by MCC, using software The problem of coordination between the Mission capabilities to both perform the task and notify astro - Control Center and the astronaut crew has some nauts — and MCC — of procedure execution status interesting features. The crew has the most up-to- [Stetson et al. 2015]); and crew self-scheduling (a date and detailed information on the state of the short demonstration to evaluate tools for astronauts spacecraft, but MCC has the most in-depth knowl - to schedule their own daily activities). edge and reasoning power, in the form of a larger Each of these demonstrations showed how to team and computing resources. This imbalance leads reduce the amount of coordination and communica - to the need for coordination. Both parties must tion between astronauts and MCC. Procedures can be exchange information, over a small communication written to include more information and reduce channel, in order to successfully perform the mis - questions that arise during procedure execution. In sion. This scenario is not unique to human space - cases where procedures or tasks require sending com - flight; similar problems arise in autonomous opera - mands and receiving data from computerized sys - tion of piloted aircraft, as well as robotic control of tems, they can be automated (essentially by writing spacecraft (for example, Mars rovers or orbiters), and software to perform the tasks). Finally, crew self- other Earth-based autonomous vehicles. The intro - scheduling reduces the need for astronauts to coor - duction of autonomy-enabling decision aids changes dinate with MCC to schedule their own activities. a two-party coordination environment into a three- However, these demonstrations did not require astro - party environment: the human operator and deci - nauts to take on the task of managing a spacecraft sion aid take turns in a tightly coupled manner, with without the assistance of MCC. a looser coupling between the autonomous system and a distant mission control function over a small communication pipe. The Autonomous Mission NASA’s interest in such decision aids includes Operations Demonstration: human piloted aircraft as well as spacecraft. Examples An Overview of developments in this area include collision detec - tion and avoidance (Kochenderfer, Holland, and For seven months during 2014 and 2015, NASA’s Chryssanthacopoulos 2012), flight path situational Autonomous Mission Operations (AMO) project awareness in modern glass cockpit aircraft (Neville and demonstrated a decision aid on-board ISS using auto - Dey 2012), emergency landing planning (Meuleau et mated planning, fault detection and diagnostic tech - al. 2011), and autonomous loss of control cueing and nologies with failure response recommendations, WINTER 2016 47 Articles easy-to-access references, and just-in-time training. steps. This two-party turn-taking model is shown in Astronauts managed multiple ISS systems, including figure 1. If there is a communication outage, transfer the total organic carbon analyzer (TOCA), a water of data or notification of next steps is delayed. It is quality analyzer, and the network of noncritical sta - notable that the crew has little or no insight into the tion support computer (SSC) laptops. TOCA analyzes current state of either water quality or system faults the quality of recycled water; doing so requires the until MCC has performed its analysis. This situation crew to sample the ISS water supply multiple times a is typical of many ISS systems today. month. The crew also performs numerous mainte - nance activities on time scales ranging from biweek - ly to annually. The SSC network functions like an How Autonomy office computer network for the crew’s use. Changes Turn-Taking Today, both of these systems are managed from the The presence of high time delay changes the story of Misson Control Center. During this demonstration, who takes the first turn. If a problem is time critical, the crew was asked to plan future TOCA water analy - then the crew may not be able to wait for MCC if sis and maintenance activities, monitor recently per - something goes wrong. The number of such cases formed TOCA activities to ensure they were per - grows as the time delay and length of communica - formed properly, diagnose hardware faults, and make tion outages grow. This is the key driver for autono - recommendations in response to any problems my; crews must be able to handle these situations on encountered. These activities were performed once or their own. However, crew workload and coordination twice a week for seven months by several ISS crew difficulty also increase with time delay. Prior work in members. Managing such systems are the kinds of understanding the impact of time delay on human living and working tasks future astronauts may need spaceflight mission operations includes a large num - to perform autonomously during future missions. ber of studies performed in different analog environ - The remainder of this article focuses on the crew ments. These are summarized in the papers by Rader tasks associated with crew monitoring TOCA per - et al. (2013) and Frank et al. (2013). formance, diagnosing TOCA faults, and recommend - The AMO software changes how turn-taking ing fault responses. For a complete discussion of the works, as shown in figure 2, by analyzing and pre - AMO experiment, see Frank et al. (2015). senting the TOCA data for the crew in real time, before flight controllers see the data. The AMO soft - How Turn-Taking Currently Works ware also informs the crew of any situations that require a response (for example, TOCA faults or off- on the International Space Station nominal water quality), as well as the recommended Current ISS operations are conducted with significant responses to the situations in question.
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