Zarrin K. Chua

Effects of Multivantage Point Systems on the Teleoperation of Spacecraft Docking

Rendezvous and docking with uncooperative target objects are driving capabilities for future robotic on-orbit servicing and space debris removal systems. A teleoperation system augments a robotic system with the perception, cognition, and decision capabilities of a human operator, which can lead to a more capable and more flexible telerobotic system. The ThirdEye system was developed in order to support the human operator in the complex relative navigation task of final approach and docking. It provides the operator with a flexible camera vantage point which can be positioned freely in the relevant space around and between the chaser and target spacecraft. The primary and secondary camera views, an attitude head-up display, and a trajectory prediction display are integrated into an intuitive graphical user interface. A validation study was conducted to evaluate the effects of this ThirdEye system on the performance of the teleoperation system during final approach and docking with uncooperative, rotating targets. The results of this study show that the ThirdEye system increases the overall task success rate by 15% and improves operator situation awareness, without having negative impact on the usage of system resources. The partial failure rates are decreased by 20-30%. In high-difficulty scenarios, the operator task load is increased due to the dual task of teleoperating the camera arm and the spacecraft in tandem, which leads to a minor increase in failure rate in these scenarios.

Integrating human factors principles into systems engineering

The objective of this paper is to examine current literature and to compile a guideline for integrating human factors principles into systems engineering. Each of the four suggested design stages — requirements acquisition, concept generation, preliminary, detailed — is characterized by a short description of the systems engineers and the human factors engineers roles and stage goals, the types of questions posed by the human factors engineer during the process, and suggested methods for integration between the two disciplines. The design process proposed in this paper is not intended to be a universal approach, but rather, a guideline for engineers regarding the overall design development process. The primary audience in this paper for this paper is systems engineers in the aerospace industry looking to better understand how to incorporate human factors into their designs.

Developing a prototype ALHAT Human System Interface for landing

NASAs Autonomous Landing and Hazard Avoidance Technology (ALHAT) project is developing technologies for safe landing anytime/anywhere on planetary surfaces. Minimizing time, thus minimizing fuel consumption, is critical during landing, so ALHAT displays must convey information efficiently to operators. The ALHAT Human System Interface (HSI) team developed prototype displays, explored methods of providing situation awareness, and modeled the cognitive task and information requirement for landing site selection. Input from NASA astronauts and mission controllers was solicited to refine ALHAT display concepts in a series of evaluations. This paper discusses the evolution of ALHAT displays and future plans for ALHAT HSI.1,2

Pilot decision making during landing point designation

Predicting astronaut performance when choosing where to land on the Moon, or the landing point designation task, is difficult. Human judgment and decision making for this application is not well-characterized. To address this knowledge deficiency, an experiment was designed to replicate the landing point designation task in both ideal and poor landing conditions. Fifteen helicopter pilots were observed to use one of two strategy types, with both strategies resulting in equatable performance. Regardless of strategy use, terrain contrast conditions were observed to have a significant impact on the selection of safe landing sites. Other aspects of performance, such as task completion time, were unaffected by terrain contrast. Pilots were also observed to be influenced by multiple terrain factors. Researchers noted twenty different types of actions stemming from nine categories of scenario cues. When these cue–action relationships are used in conjunction with pilots’ evaluation criteria and a known strategy, models can be developed to predict decision making.

Current State of Human Factors in Systems Design

Many papers at previous HFES Meetings have touched on the theme of how to either incorporate human factors earlier in the design process, including development of new methods and discussion of what existing methods and tools are applicable at the preliminary and conceptual design phases. To many HFES members, these questions are not an academic exercise, but daily challenges. The goal of this discussion panel is to summarize the current state of human factors in systems design, particularly outside of the context of human factors-centric operations and to assess the gaps in human factors methods to support the incorporation of human factors earlier in the design process. Panel members represent industry organizations who work daily to incorporate good human factors principles into design.

Quantifying Pilot Performance During Landing Point Redesignation for System Design

The requirements for the next generation of lunar landers include being capable of landing in terrain that is both poorly lit and hazardous, increasing the importance and difficulty of an already critical mission task known as landing point redesignation. During this task, the crew interacts with an on-board automated flight system to finalize the touchdown point. This paper presents the results of a study conducted to quantify pilot performance and task completion time during landing point redesignation; the effect of environmental and mission parameters on those measures; and a design space exploration using human performance contours for different definitions of performance.Additionally, this paper presents the analysis of a comparison between a reference automated system and the pilots’ site selection performance. The pilots completed the task in an average of 20 s. The number of identifiable terrain markers, landing points of interest, and the pilot’s expectation of terrain features had effect sizes too small to be detected in this experiment. Human performance was found to be best when the importance of fuel consumption was weighted less than system safety or proximity to points of interest. In these same conditions, the human pilot was also observed to perform better than a reference automated system. Fuel penalty associated with prolonged decision time remains the largest detriment to human landing point redesignation task performance.

Examination of human performance during lunar landing

Experimentally derived data was extrapolated to compare the lunar landing performance of human pilots to that of an automated landing system.12 The results of this investigation are presented. Overall, the pilots performed equal to or better than the automated system in 18% of the relevant cases, but required more fuel. Pilot site selections were further investigated as a function of the time to complete. Each hypothetical case was compared to the automated system, across a range of performance criteria weighting distributions. This performance criteria is threefold - proximity to point of interest, safety of the site, and fuel consumed. In general, the pilots perform better than the automated system in terms of safety and proximity to points of interest criteria. However, as the priority of fuel conservation increases, the tradeoff between using an autonomous landing system versus a human-in-command system favors the automation, especially if the pilot is not able to make the proper decision within a performance criteria specific threshold.