The first year of this Directed Research Project (DRP) achieved its two main goals: (1) to provide specific guidance on the selection of workload measurement techniques for particular human tasks and activities; and (2) to outline how human workload can be best managed across a mission. This guidance, provided in the form of a NASA Technical Memorandum entitled “Measuring and evaluating workload: A primer” (Casner, & Gore, 2010; herein referred to as the Workload Primer, WP), considered the negative effects of high and low workload but also recognized the need for human operators to vigorously exercise critical skills in a balanced regime of work and rest. The techniques and guidance provided in the WP protocol section were tested in a practical spaceflight application by the Information Presentation DRP and refined in later phases of the Workload DRP. The research conducted in this first year was conducted to address the needs of spaceflight application designers to unobtrusively measure workload, and to create appropriate levels of human workload through the allocation of work between human spaceflight crew and automated systems. At the end of the first year, a gap on workload measurement and management was revealed, namely the need to identify research on workload during long duration operations and ways to measure it unobtrusively.

The second and third year of the workload DRP applied the findings from the first year to consider specific system level concerns regarding workload’s impact on the system performance over long duration operations. For example, in order to determine the acceptable system level of workload, an understanding of the effects of workload on repeated multitask performance, over extended operations, with additional crewmembers is required. The ultimate goal was to provide answers to the following human-system related workload questions: (1) how to measure workload from a system perspective; (2) how to maintain workload at levels that ensure robust human performance throughout the mission timeline; and (3) how can the human-system related workload guidance be used in future space flight operations. Five primary tasks were completed to provide answers to these questions: (1) identify Crewmembers’ operational environment and workload considerations using Data Summaries regarding Architecture and Volume Design, Procedures, and Planning and Scheduling developed from the Flight Crew Integration (FCI) International Space Station (ISS) Life Sciences Crew Comments Database; (2) identify the commonalities between workload measured at the individual level and workload from the system level; (3) host a scales and measurement workshop; (4) conduct a Usability evaluation of the updated Primer’s protocol section; and (5) develop a meaningful conceptual representation of the variables that influence workload management as applied to system performance and evaluation. These five tasks have culminated in the identification of system-related workload variables, in the development of two candidate conceptual models for measuring system workload over long duration operations, and in one new technology-based option to unobtrusively measure workload. The outcome of the Workload DRP lists several recommendations on the use of workload measurement approaches for long duration mission operations.

Rather than itemizing sources of workload issues, the report completed by the Workload DRP concludes by emphasizing a system-level perspective of workload, with three levels or themes that emerge consistently over the course of studies. The first level can be thought of as the social dynamics impacted by long-duration stresses, and act as the psychological backdrop to all behaviors and performance. These social dynamics include stresses stemming from language barriers, cultural differences in leadership, and coping strategies. The second level pertains to workload as it is more traditionally conceived, involving usability, planning, procedures, and scheduling. The third level refers to workload that stems from institutional and organizational cultural practices. It takes the form of debriefs and practices in gradient dissent, but now must also incorporate a system-wide and standards perspective in the practice of human factors amongst NASA and its contractors.

Results from the studies conducted and the methodical approach undertaken as part of the three year Workload DRP was the development of two conceptual models of the manner that workload impacts people over a longer duration mission. It is anticipated that the conceptual models of long duration operations be refined through additional research evaluations on extreme environment operations, particularly the manner that the individual workload considerations are raised to the system level. The effort taken to develop the conceptual models culminated in a set of requirements that has been provided to the Orion community to help in the design of workload requirements for long duration mission operations.

Technologies have also been highlighted in various developmental stages that may provide unobtrusive ways to measure workload, while providing feedback to astronauts who can use the information to manage their tasks with the ultimate goal of insuring safety of the entire system in order to achieve mission success. In terms of the technology-based option, a prototype mobile screening system that unobtrusively detects behavioral patterns and characteristics of individuals who perform specific actions will be required. Such a prototype system will track the homeostasis of an individual’s pupil, skin/pore dilation, or other characteristic behavioral patterns and compare the baseline data to conditions when the operator experiences excessive workload. Sensor technology will be used to measure and monitor physiological, behavioral and auditory markers characteristic of individuals that experience performance decrements due to workload over a long duration mission. Research is needed to specify the markers and the thresholds that are characteristic of such performance changes. Data collection of physiological information (ocular measures, temperature, heart and breathing rates, perspiration, pore dilation, vocal measures), of behavioral information (physical movements/patterns, facial recognition measures), and of auditory information (pitch of voice) will be required so that baseline profiles can be created. These baseline profiles can then be compared against profiles of situations that are associated with performance decrements. These physiological, behavioral, and auditory markers will serve as the requirements specifications for systems developed for use in long duration mission missions. Research is required to identify the critical thresholds for the physiological, behavioral, and auditory markers over a longer duration space mission.