Information Flow Model of Human Extravehicular Activity Operations Matthew J. Miller Kerry M. McGuire Karen M. Feigh Georgia Institute of Technology NASA Johnson Space Center Georgia Institute of Technology 270 Ferst Drive, Room 416 Mail Code: SF3 270 Ferst Drive, Room 419 Atlanta, GA 30332 2101 NASA Parkway Atlanta, GA 30332 912 674 6722 Houston, TX 77058 404 385 7686 [email protected] 281 483 0786 [email protected] [email protected] Abstract— Future human spaceflight missions will face the therefore requiring supplemental or independent life complex challenge of performing human extravehicular support equipment for the astronaut” [3], pg. 5. The vast activity (EVA) beyond the low Earth orbit (LEO) majority of EVAs conducted to date have all occurred in a environment. Astronauts will become increasingly isolated region above Earth (~100 to 1000 km) known as Low from Earth-based mission support and thus will rely heavily Earth Orbit (LEO). The Apollo EVAs serve as the only on their own decision-making capabilities and onboard tools to accomplish proposed EVA mission objectives. To better precedent for EVAs beyond LEO, yet even these EVAs address time delay communication issues, EVA characters, operated within the Earth-Moon system. A universal e.g. flight controllers, astronauts, etc., and their respective characteristic inherent among all performed EVAs is the work practices and roles need to be better characterized and absences of delayed communication linkages between understood. This paper presents the results of a study crew and mission control due to light-time delay. Light- examining the EVA work domain and the personnel that time delay is associated with the vast distances the operate within it. The goal is to characterize current and communication relays must travel to reach mission historical roles of ground support, intravehicular (IV) crew control located on Earth. Table I summarizes the one way and EV crew, their communication patterns and information time-delay for transmissions sent between Earth and needs. This work provides a description of EVA operations and identifies issues to be used as a basis for future various destinations currently under examination for investigation. future exploration missions. TABLE OF CONTENTS Table I. Potential Future Human EVA Environments 1. INTRODUCTION ................................................. 1 Destination Lunar NEOs Mars Lunar DRO Close Opposition 2. BACKGROUND ................................................... 2 Distance from 3.84E+05 Variable 5.57E+07 4.01E+08 3. METHODS AND MATERIALS ............................. 3 Earth, km 4. HUMAN EXTRAVEHICULAR ACTIVITY ............ 4 One-Way Time 185.8 1338.6 1.3 Variable 5. EVA INFORMATION FLOW MODEL ................. 6 Delay, s (min) (3.1) (22.3) 6. APOLLO 16 EVA 4 COMMUNICATION Mission Variable 20-30 895-950 ANALYSIS .............................................................. 9 Duration, days 7. DISCUSSION ..................................................... 13 Ref. [4] [5], [6] [4] 8. CONCLUSIONS AND FUTURE WORK ............... 14 Central to the theme of this study and future works is to 9. ACKNOWLEDGEMENTS ................................... 14 better understand the current EVA work domain with the REFERENCES ....................................................... 14 eventual goal of understanding EVAs in the context of BIOGRAPHY ........................................................ 15 deep space, communication time-delayed missions. More 1. INTRODUCTION specifically, how will the paradigm between mission control center (MCC) and onboard crewmembers have to The NASA human spaceflight program has successfully change to ensure EVA mission success without real-time completed well over 1326 hours of extravehicular activity communication? Current EVA operations leverage 50 (EVA) throughout its 50 year history [1]. Thanks to the years of EVA experience operating with the real-time incremental developments made throughout the Gemini, communication support capability by MCC, with the Apollo, Skylab, Shuttle, and International Space Station exception of periodic loss of signal events. (ISS) programs, EVAs have become one of NASA’s most iconic and essential component of human spaceflight, Goals of this Investigation demonstrating a range of capabilities including hardware assembly, maintenance, and repair as well as scientific The purpose of this study is to identify the primary and support [2]. For the purposes of this study, an EVA is secondary operators involved in conducting an EVA in defined as “any space operation or activity performed present-day operations. The goal is to characterize current outside the protective environment of a spacecraft and roles and responsibilities of these operators, and to 978-1-4799-5380-6/15/$31.00 ©2015 IEEE 1 examine their communication patterns and information areas of decreased efficiency such as support equipment needs. This work provides a current day perspective of setup. However, no evaluation or conclusions were made EVA operations and identifies issues to be used as a basis regarding MCC support activities or how MCC support for future investigation. A communication link analysis of integrated with crewmember activities. an historical EVA is also shown to provide a synthesized view of actual flight audio during an EVA. Apollo 16 The work that has focused on the interactions of MCC EVA 4 was selected as a case study because it serves as and crewmembers, particularly within a time-delayed the only EVA conducted beyond LEO that was not environment, exists in analog simulation. There are affiliated with operating directly on the moon’s surface. numerous analog sites where field-testing of hardware This operational environment is analogous to the future and spaceflight operations occurs such as NASA Extreme asteroid redirect missions currently being planned by Environment Mission Operations (NEEMO) and Desert NASA [5]. Research and Technology Studies (D/RATS). Recent lessons learned from these analog studies indicate the The rest of the paper is organized as follows. The complimentary nature of having both voice and text literature review is outlined in Section 2, followed by the capability for crew and MCC communication. In the discussion of the research methods in Section 3. Section 4 presence of 50-second communication latency, MCC and provides an EVA description. The EVA information flow EVA crewmembers demonstrated they could operate and model and communication analysis is presented in meet their mission objectives, if the EVA timeline was Section 5 and 6, respectively. A discussion of the results constructed to accommodate the round-trip and study limitations is located in Sections 7 and communication delay with MCC. However, when conclusions along with proposed future work are unexpected situations were simulated, communications discussed in Section 8. broke down for both 5 and 10-minute latencies [16]. There is a demonstrated need to better understand EVA 2. BACKGROUND operations within this time-delayed environment and to assess the potential impacts of crew training and EVAs have been a topic of study from a variety of technological support. perspectives ranging from procedural timeline development [7], tool development [8], and human health Along with field-analogs, virtual simulations have also and performance [9]. The majority of studies have been conducted at NASA JSC though the RATS 2012 focused solely on evaluations of either the EVA campaign [17] and the Autonomous Mission Operations crewmembers or MCC. However, the existing literature (AMO) study [18]. Both of these studies employed a lacks an examination of the interactions between MCC series of virtual reality simulation environments to mimic and crewmembers during real-time operations. deep space operations. RATS 2012 reiterated the importance of having a dedicated intravehicular activity Previous studies have examined the MCC to understand (IVA) crewmember to handle communications with how MCC flight controllers and support staff support ground communication, similar to how both Shuttle and real-time human spaceflight activities [10], [11]. The ISS EVAs operated. However, this study, along with the MCC is divided among a set of console positions and previous field-analog simulations, lacked an examination primarily communicates via a set of voice communication of the information needs, communication patterns, and loops (see Ref. [10] for a description of MCC structure work practices of the EVA operators to explain the and voice loops). MCC studies to-date have not reasons for the observed performance in operations. specifically examined the EVA domain. This study contributes to this body of knowledge by focusing on the While not specifically examining EVA operations, the specific set of voice loops and console positions within AMO study, conducted at the Deep Space Habitat at JSC, MCC known as the EVA front control room (FCR) provides some insight to the possible technological console and EVA multipurpose support room (MPSR) impacts related to mitigating time-delay impacts from console positions. both the MCC and crew perspective. This study examined a baseline and mitigation configuration to experimentally Crewmember focused research includes time and motion investigate whether different technology aides could studies [12], [13] and evaluations of task efficiency [14], mitigate some of the challenges caused by time-delay. [15]. In particular, Ney and Looper, by examining task Workload and