Part-task Simulation Research Articles

Virtual reality in general surgical training

BACKGROUND: Virtual-reality simulation in surgical training has become more widely utilized and intensely investigated as the result of changes in residency structure and the need to develop safer, more efficient, and measurable training processes. METHODS: The use of surgical virtual-reality devices and their evolution from simple nonanatomic and nonhaptic basic-skills trainers to whole-procedure and part-task procedural simulators are reviewed. RESULTS: A range of virtual-reality devices can currently be used to train laparoscopic manipulative tasks and flexible endoscopic tasks. Current data indicate that these training devices are of significant value in building surgical resident skills. Newer devices can be enabled with haptics, mentoring, and enhanced performance measurement capabilities. CONCLUSIONS: If executed properly, virtual reality offers inherent advantages over other training systems. The most important of these is facilitation of performance measurement, which makes proficiency-based training feasible. Accruing experience with multiple simulation systems indicates that this type of training is valuable and accessible. Significant challenges remaining to be overcome before wider implementation of training and assessment with these devices can occur include validation as well as the identification of resources for procurement and ongoing development.

Task Prioritization Factors: Two Part-Task Simulator Studies

Cockpit task management (CTM) is the initiation, monitoring, prioritization, execution, and termination of multiple, concurrent tasks by flight crews. In this research, we used 2 part-task simulator studies to elicit from pilots the factors actually used in task prioritization. Analysis resulted in the identification of 12 specific factors that the pilots reported as affecting task prioritization. From the results of these and related studies, we developed a hypothetical framework and model of task prioritization in which procedural consistency, importance to flight safety, and the salience of task-related stimuli are the primary factors that affect task prioritization.

Simulation technology in training students, residents and faculty

We provide an overview of the developments in medical education and assessment using high-fidelity simulation. Both descriptive and research papers recently published in the English language are included in this review. The majority of articles reviewed are descriptive in nature, outlining the use of simulation for various educational purposes in undergraduate, postgraduate and continuing medical education. Some articles focus on the use of simulation for the acquisition of technical skills in different surgical disciplines using part-task simulation. Other disciplines such as emergency medicine, critical care, paediatrics and nursing have also contributed to the literature in this area. Very little research in the area of simulation is evident in the literature addressing the actual value or the reliability and validity of high-fidelity simulation as an evaluation tool during this time period. A strong interest in decreasing human error and the improvement in patient safety may indicate the future direction of high-fidelity simulation. Simulation is receiving increasing support as an educational tool and in its use for evaluation purposes. Research into this area is still somewhat limited. As the research impetus increases in the future, we may see simulation as a major focus in all disciplines with respect to its use in the improvement of patient safety. Team training, including both personality and attitudinal issues similar to those performed in other high hazard industries, may become increasingly evident in the literature in the coming decade.

Examining new Flight Deck Technology using Human Performance Modeling

Aircraft flight deck synthetic vision systems (SVS) always provide a “clear day” view and hence have the potential to improve safety in commercial aviation. Approach, landing, and taxi operations will most readily profit from the SVS capabilities. A part-task simulation study provided data on pilot performance using a baseline and an SVS-equipped flight deck. One effect of adding the separate SVS to the flight deck was that pilot scan patterns changed significantly—more time was devoted to the attitude displays and less to the navigation display. Concern over the change in well-established scan patterns lead to the suggestion that the SVS, an attitude display, be combined with the primary flight display as a single Enhanced-SVS attitude display rather than augment it as a separate display. A human performance model study was used to reproduce the results of the part-task study and then establish that the Enhanced-SVS attitude instrument would restore the original pilot scan pattern.

The Effectiveness of Various Attitude Indicator Display Sizes and Extended Horizon Lines on Attitude Maintenance in a Part-Task Simulation

Spatial disorientation (SD) is a constant contributing factor to the rate of fatal aviation accidents. SD occurs as a result of perceptual errors that can be attributed in part to the inefficient presentation of synthetic orientation cues via the attitude indicator when external visual conditions are poor. Improvements in the design of the attitude indicator may help to eliminate instrumentation as a factor in the onset of SD. The goal of the present study was to explore several display concepts that may contribute to an improved attitude display. Specifically, the effectiveness of various display sizes, some that are used in current and some that are anticipated in future attitude displays that may incorporate Synthetic Vision Systems (SVS) concepts, was assessed. In addition, a concept known as an extended horizon line or Malcolm Horizon (MH) was applied and evaluated. Paired with the MH, the novel concept of a fixed reference line representing the central horizontal plane of the aircraft was also tested. Subjects' performance on an attitude control task and secondary math workload task was measured across the various display sizes and conditions. The results, with regard to display size, confirmed the “bigger is better” concept, yielding better performance with the larger display sizes. A clear and significant improvement in attitude task performance was found with the addition of the extended horizon line. The extended or MH seemed to equalize attitude performance across display sizes, even for a central or foveal display as small as three inches in width.

Training Pilots to Prioritize Tasks

The purpose of this study was to develop and evaluate the effectiveness of a technique to help pilots prioritize tasks. A part-task simulator experiment was conducted in which three groups of general aviation pilot participants flew pre-and post-training flights. Participants in two groups received task prioritization training between the flights while those in a control group did not. Task prioritization error rates and prospective memory error rates from pre-and post-training flights were compared. Task prioritization and memory error rates improved in the training groups and did not improve in the control group. However, these findings must be considered preliminary, as several issues remain to be resolved by follow-on studies.

Influence of Icing Information on Pilot Strategies for Operating in Icing Conditions

Theine uenceofpotential remoteice-detectionsystem featuresonpilotdecision makingwasinvestigated through a Web-based experiment. Display features including a graphical plan view depiction of icing severity, vertical view depiction, single and multiple icing severity levels as well as sensor range were varied in a part-task simulation experiment. Using information from each display, pilots were presented with a set of four e ight scenarios and probed on theirrouting decisions and comfort level with thosedecisions. Theexperimentalso included a subjective display preference evaluation. Results show that all of the displays improved pilot decision making over existing text-based icing information. The three-dimensional displays that included vertical depiction of icing conditions were found to support improved decision making. Range was not found to be a strong factor in the experiment; however, the minimum range tested was 25 n miles, which may be in excess of current technical capabilities. The depictionoftheseverity oficingconditionswasnotfoundto beasimportantasaccurateinformation on thelocation of icing conditions.

Nuclear Reactor Control Room Simulators: Human Factors Research and Development

Simulator studies are powerful means for understanding, designing and managing the complexity of nuclear reactor control if, along with their scenarios, they are correctly designed for that purpose. This contribution to an international state of the art of the use of nuclear reactor control room simulators in human factors research and development summarises the trends and novelties in the theories and methodologies (the reduction of the ambitions of cognitive simulation and the renewal of process-tracing methods, the eclectic search for theoretical and methodological complementarity, the conquests of situation awareness and their limitations, the study of cooperation), in the use of the results (with stress on probabilistic human reliability analysis and design of procedures) and in the construction of simulated situations (with stress on part task simulations and on relations between testing practical and empirical hypotheses and testing theoretical ones).

An Empirical Validation of Subjective Workload Ratings

A correlational design was used to regress NASA TLX subjective workload ratings onto several potential independent variables (i.e., the number of concurrent tasks, task combination, task resource demands, and flight experience) to determine task characteristics that influence pilot subjective workload ratings. A part task simulator was used to present up to six concurrent tasks, in different combinations, to 27 cadets at the USAF Academy. The results indicated the number of concurrent tasks had the largest impact on subjective workload ratings. In terms of multiple resource theory, spatial, verbal, and visual demands (in that order) contributed the most variance. The implication for theoreticians and designers is that the number of concurrent tasks, mental resource demands, and time constraints seem to be key contributors to subjective workload ratings.

Evaluation of Hand-Dominance on Manual Control of Aircraft

In the transport aircraft community the non-dominant hand control of aircraft is the norm. This historical precedence may be biasing the cockpit designs of the newer fly-by-wire aircraft which utilize a small sidestick controller rather than a wheel-column. Very little data are available to determine what effect non-dominant hand control using small throw controllers has on the pilot operator. To provide such data, a part-task simulation study was undertaken. Three different compensatory tracking tasks were performed with both left and right hand-controllers. Six right-hand dominant and three left-hand dominant subjects performed all three tasks, with both controllers. The results indicate that performance degraded and workload increased when the pilots were forced to use their non-dominant hand.

Image quality issues for an enhanced vision head up display

A part task simulation study was performed to determine the ability of pilots to land an aircraft using head up display (HUD) guidance symbology overlaying an emulated millimeter wave imagery. The task was to land in Category IIIa weather at a Category I facility. Three image parameters were varied: image update rate, image processing latency, and the luminance contrast ratio of the runway image to the background noise. ILS beam bending that was representative of a Category I facility was randomly varied across the experimental runs. Nine pilots completed the test matrix. The only variable that made a significant difference was the runway to background contrast ratio. >

Experimental Study of Electronically Based Instrument Approach Plates

Issues associated with the electronic presentation of instrument approach plates (IAPs) were investigated in a part-task simulation study using the Massachusetts Institute of Technology Aeronautical Systems Laboratory's Advanced Cockpit Simulator. Several electronic IAP chart formats were developed and evaluated. A decluttering system that allowed the pilots to selectively suppress various information groups in some of the prototype formats was also investigated. Results of the experimental study indicated that there was no degradation, and possibly a limited gain in information-retrieval performance when IAP information was presented in electronic format and compared to traditional paper IAPs. Each pilot preferred the selectable decluttering feature. The preferred chart was a color, north-up (nonmoving map) format with the decluttering capability. During the simulation, low levels of terrain situational awareness were observed when pilots were given erroneous air traffic control vectors toward hazardous terrain.

An Exploratory Study of Plan-View Terrain Displays for Air Carrier Operations

Two prototypical terrain situational awareness (TSA) displays were examined in a preliminary part-task simulation study using the MIT Aeronautical Systems Laboratory Advanced Cockpit Simulator. Pilots, qualified on autoflight aircraft, flew simulated approaches while using a moving-map terrain display in addition to typical glass-cockpit navigation displays. During the simulation, TSA was evaluated by issuing erroneous air traffic control (ATC) vectors toward hazardous terrain. When given vectors toward such terrain, there was a 50% overall hazard-recognition rate when pilots used a terrain display based on current terrain-depiction methods and a 78% recognition rate when using a terrain display based on smoothed-contour terrain depiction. After the subject-pilots realized they could not rely on ATC for terrain separation, hazard-recognition rates increased from 20% to 62% for the display based on current depiction methods and from 25% to 93% for the smoothed-contour display. Advanced terrain displays app...

An Empirical Evaluation of Tools to Aid in Enroute Flight Planning

After a number of background studies (including surveys, a simulator study, and interviews with commercial air traffic controllers, dispatchers, and pilots), several design concepts have been developed to guide in the design of tools to aid in enroute flight planning activities. Alternative versions of these tools have been implemented in the Flight Planning Testbed (FPT), a part-task simulation environment for studying interactions with flight planning tools. This testbed, which runs on a Macintosh IIfx, presents scenarios and records all interaction with the operators. Thirty commercial airline pilots participated in a between-subjects experiment involving three alternative system designs and four flight planning scenarios. The results provide some very interesting insights into planning strategies and the effects of cognitive tools on those strategies.

Simulation and the user interface : Taylor & Francis, London, 1990, 269 pp

Simulation and the user interface: an introduction, M.A. Life. Part 1 General issues: extrapolating from one task to another, L. Bainbridge a conceptualization of simulation for user interface development, M.A. Life indivisibility, inseparability and indiscernibility: some problems with simulations for complex domains, A. Taylor & J. Browne simulation: a stepping-stone between requirements and design, D. Diaper operational evaluation, V.D. Hopkin. Part 2 Embedded simulations: cognitive modelling as a simulation technique for the development of intelligent user interfaces, P.C. Cacciabue, F. Decortis, M. Masson, & J.P. Nordvik simulation in the evolution of an intelligent speech interface, J. Monaghan, C. Cheepen, J. Hewitt, & J. Hobson simulating peer interaction vias computer-based 'help' facilities, C.J. Colbourn & T. Cockerton-Turner simulation directionality in airbourne auditory warnings and messages, P.L.N. Naish. Part 3 Techniques and applications: discrete dialogue computing systems: detail: an approach to task analysis, D. Edmondson & P. Johnson simulating the speech operated user interfaces of the future: the case of listening typewriters, R. Dye, J.L. Arnott, A.F. Newell, K.E.P. Carter, & G. Carter, & G. Cruickshank using hypertalk as a specificaion tool and a simulation vehicle in the development of a personal database system, D. Young, M.W. Lansdale, & C.A. Bass simulating user interfaces with dBASEIII+ , M.P. Lee, M.W.M Darling, D. Peacock, & S. Jeffreys simulation and military cockpit voice interface, B. McGuinness. continuous dynamic control systems: optimising the pilot-display interface using part-task simulation: a case description, H. Dudfield part-task simulation as a tool to investigate the effects of types of lag on positioning performance, S.E. Jensen the application of manual tracking simulators as aids to system development and evaluation, J.L. Evans an object oriented design approach incorporationg simulation in the development of a Real-Time control system, R. Frank & J. Hewitt.

A Testbed for the Evaluation of Computer Aids for Enroute Flight Path Planning

We have conducted a simulator study of five airline flight crews engaged in various enroute planning activities. Based on a cognitive task analysis of this data, a flight planning workstation has been developed on a Mac II controlling three color monitors. This workstation is being used to study design concepts to support the flight planning activities of dispatchers and flight crews in part-task simulations.

Prediction of Tank Gunnery Simulator Performance Using the Apts Battery

This research investigates the efficacy of the Automated Performance Test System (APTS), a battery of tests measuring basic psychomotor, cognitive, and spatial abilities, to predict complex psychomotor performance on two part-task tank gunnery simulators, TOPGUN and the Videodisk Gunnery Simulator (VIGS). It was hypothesized from past research that the Manikin, Simultaneous Pattern Comparison, and Four-Choice Reaction Time subtests of the APTS would be predictive of TOPGUN and VIGS performances. Additional research goals were to examine the stabilities and reliabilities of APTS, TOPGUN, and VIGS. Forty male undergraduate students were tested on the APTS; afterward, they completed either TOPGUN (N = 20) or VIGS (N = 20) training. Results obtained indicated that Code Substitution, Manikin, and Pattern Comparison were predictive of tank gunnery simulator performance at the p =.01 level. It is concluded that 1) these results need to be replicated, due to the complexity of the analyses conducted, 2) the APTS were found to be very stable and reliable, but TOPGUN and VIGS measures were unreliable, and 3) the unreliable simulator measures limited APTs' surrogate potential.

The Interactive Display Design Tool: An Application Program for Part-Task Simulation Development

Traditionally, part-task simulation development has involved large amounts of time and effort. This was due to: 1) the inherent complexity of designing real-time software; 2) difficulty of converting dea/concept into specific software engineering requirements/specifications; 3) the need for extensive interconnected computer systems (both graphical and non-graphical). There are 3 activities involved in the creation of a part-task simulation: 1) the physical display format; 2) the definition of the input (Simulation Logic); 3) the definition of the response to the inputs (Display Logic). The Interactive Display Design Tool (IDDT) was a concerted effort to allow parts of the external interface to be created directly by interface designers, rather than software engineers. The original version of IDDT allowed the designer to interactively create and modify display formats. The current capability of IDDT allows interface designers to partially create and modify display and simulation logic. This paper discusses the specific methodology used within IDDT: display lists and look-up tables, and cites examples and capabilities of the tool. In conclusion, specific instances of significant savings in time and effort required for part-task simulation creation are given.

An Assessment of Display Formats for Crew Alerting and Guidance

During the last 13 years the investigation of crew alerting during non-normal situations has progressed from the study of a single system, altitude monitoring, to a consideration of the total system. The result of this progression is that a highly self-contained system concept has been defined that will facilitate an effective crew response to both normal and non-normal situations. The concept system is intended to not only monitor aircraft systems and flight operations, but also provide improved guidance and status information. The form the information takes will ultimately affect the timeliness of information perception, processing, and crew performance. This paper describes three studies conducted to assess the relative effectiveness of selected display formats in communicating time-critical information to commercial airline pilots. A part-task simulation was used to collect response time and number of errors. Format type, format complexity, and format symbology were varied in this evaluation. Results showed that response to symbolic formats without alphanumerics was faster and more accurate than to symbolic formats with alphanumerics or alphanumeric only formats. These results were incorporated into a full mission aircraft simulator for evaluating the effectiveness of the system concept and eventual incorporation into FAA guidelines for future commercial aircraft.

Predictor Displays for Complex, Dynamic Tasks: A Preliminary Investigation

The operators of nuclear power plants are asked to perform a task that has proven to be particularly difficult: manual control of feedwater during startup. We have initiated a research and development program to address human factors issues related to this task. An analysis of cognitive aspects of the feedwater control task was used to develop a generic part-task simulator. New displays to enhance manual control performance (including a predictor display) were developed with the simulator. The test capability provided by the simulator allowed precise measurement of performance differences associated with these displays in a mixed-fidelity laboratory experiment. The results suggest that the displays reduced the complexity of the task and resulted in improved operator performance.