Biomedical subjects

M R Endsley

Publications and source records attributed to M R Endsley.

4 recordsLinked to original sources

PubMed1999

Level of automation effects on performance, situation awareness and workload in a dynamic control task.

Various levels of automation (LOA) designating the degree of human operator and computer control were explored within the context of a dynamic control task as a means of improving overall human/machine performance. Automated systems have traditionally been explored as binary function allocations; either the human or the machine is assigned to a given task. More recently, intermediary levels of automation have been discussed as a means of maintaining operator involvement in system performance, leading to improvements in situation awareness and reductions in out-of-the-loop performance problems. A LOA taxonomy applicable to a wide range of psychomotor and cognitive tasks is presented here. The taxonomy comprises various schemes of generic control system function allocations. The functions allocated to a human operator and/or computer included monitoring displays, generating processing options, selecting an 'optimal' option and implementing that option. The impact of the LOA taxonomy was assessed within a dynamic and complex cognitive control task by measuring its effect on human/system performance, situation awareness and workload. Thirty subjects performed simulation trials involving various levels of automation. Several automation failures occurred and out-of-the-loop performance decrements were assessed. Results suggest that, in terms of performance, human operators benefit most from automation of the implementation portion of the task, but only under normal operating conditions; in contrast, removal of the operator from task implementation is detrimental to performance recovery if the automated system fails. Joint human/system option generation significantly degraded performance in comparison to human or automated option generation alone. Lower operator workload and higher situation awareness were observed under automation of the decision making portion of the task (i.e. selection of options), although human/system performance was only slightly improved. The implications of these findings for the design of automated systems are discussed.

Adult↗

PubMed1998

The effect of automated compensation for incongruent axes on teleoperator performance.

Teleoperation is frequently performed with misalignments between operator or camera viewing direction and controller orientation. Examples of this occur in endoscopic surgery and in teleoperation with multiple camera views. The objective of this study was to find a method to automatically compensate for those misalignments so that human operators performing tasks under such scenarios could achieve levels of performance comparable to aligned conditions without additional training requirements. In this paper we report on a set of experiments conducted to test a method developed for that purpose. Participants were asked to track a randomly moving target on a computer display using a cursor controlled with a joystick. Performance was recorded under various visual-motor misalignments with and without automated compensation. Results indicated significant improvements in operator performance through use of automatic compensation only under certain types of misalignment. Actual or potential applications of this research include teleoperation and endoscopic surgery.

Data Display↗

PubMed1996

Sources of situation awareness errors in aviation.

BACKGROUND: Situation Awareness (SA) is a crucial factor in effective decision-making, especially in the dynamic flight environment. Consequently, an understanding of the types of SA errors that occur in this environment is beneficial. METHODS: This study uses reports from the Aviation Safety Reporting System (ASRS) database (accessed by the term "situational awareness") to investigate the types of SA errors that occur in aviation. The errors were classified into one of three major categories: Level 1 (failure to correctly perceive the information), Level 2 (failure to comprehend the situation), or Level 3 (failure to project the situation into the future). RESULTS: Of the errors identified, 76.3% were Level 1 SA errors, 20.3% were Level 2, and 3.4% were Level 3. Level 1 SA errors occurred when relevant data were not available, when data were hard to discriminate or detect, when a failure to monitor or observe data occurred, when presented information was misperceived, or when memory loss occurred. Level 2 SA errors involved a lack of or an incomplete mental model, the use of an incorrect mental model, over-reliance on default values, and miscellaneous other factors. Level 3 errors involved either an overprojection of current trends or miscellaneous other factors. CONCLUSIONS: These results give an indication of the types and frequency of SA errors that occur in aviation, with failure to monitor or observe available information forming the largest single category. Many other causal factors are also indicated, however, including vigilance, automation problems, and poor mental models.

Accidents, Aviation↗

PubMedDate not supplied

Auditory localization for spatial orientation.

The use of three-dimensional auditory technology that provides localization of auditory cues presented through headphones is proposed as a means of providing supplemental information to pilots on the spatial orientation of an aircraft. This technique shows promise for reducing accidents due to spatial disorientation associated with high visual load. A study was conducted using United States Air Force pilots as subjects to determine desirable¿ cue characteristics for accurately localizing auditory cues using this technique. The study examined the use of 9 different cue types at each of 2 frequency levels. It was found that the accuracy of subjects' localization of cues in elevation was greatly enhanced by the use of multidimensional cues that provided redundant elevation information through varying frequencies and distance from the horizon cues in addition to the inherent spatial location information. Trade-offs in azimuth localization accuracy and response time were noted, however. Recommendations are made for further developing and investigating this technique for the aircraft spatial orientation task.

Accidents, Aviation↗