Mireille Raby

Procedures for Investigating and Reporting Fatigue Contributions to Marine Casualties

This project was aimed at identifying strategies for improving current U. S. Coast Guard (USCG) procedures for investigating, reporting, and analyzing fatigue contributions to marine casualties. The focus was on evaluating the contribution of fatigue in vessel and personnel injury casualties. A total of 397 casualties were investigated. Fatigue contributed to 16 percent of the critical vessel casualties and 33 percent of the personnel injury casualties. These estimates were substantially greater than the ones currently available from the USCG Marine Investigations Module (MINMOD) database. Analyses identified three potential indicators of fatigue: (1) the number of fatigue symptoms reported by mariners, (2) the number of hours worked in the 24 hours prior to a casualty; and (3) the number of hours slept in those 24 hours. This study demonstrated the feasibility of using simple procedures to obtain meaningful data on the contribution of fatigue in transportation accidents.

Defining the Interface for a Snowplow Lane Tracking Device Using a Systems-Based Approach

This paper summarizes a systems-based approach to the design of an operator interface for a “Magnetic Lateral Guidance and Warning System” for snowplow operations. The premise behind this interface is that providing continuous and accurate lane position information to complement existing roadway cues may increase driver situation awareness, and potentially reduce crash involvement. An extensive survey returned by over 1000 snowplow operators from Minnesota and Iowa identified operational issues critical to low-visibility operations. Survey findings and ride-along interviews supported an Operator Function Model - Cognitive Task Analysis (OFM-COG). The OFM-COG describes operational constraints and links them to the cognitive limits of drivers in order to identify critical functionality and preliminary design criteria. Findings suggest that the interface be designed as an “aid,‘ rather than as a “primary’ display, to complement existing roadway cues. The visual display should be augmented with haptic cues such as directional seat vibration and peripheral visual, and all alarms should have adjustable thresholds. A prototype user interface is presented.

Network Analysis as a Technique to Guide the Task Analysis of ATIS/CVO

Applications of Advanced Traveler Information Systems (ATIS) and Commercial Vehicle Operations (CVO) include technology ranging from simple sensors and alarms to complex combinations of databases and displays. This range of technology will impose a variety of task demands on drivers, and these demands need to be cataloged. Without a means of focusing the task analysis describing these systems, a complete description of all possible interactions among the potential functions of ATIS/CVO systems would be intractable. To address this problem, we have adopted network analysis techniques from sociological and anthropological studies of social groups as a tool to examine complex systems and to guide a task analysis. Network analysis provides a quantitative analysis of information flows that link system functions that can focus a task analysis on important functions and critical interactions between these functions. This paper describes measures of centrality and clusters and how these measures can guide any complex task analysis in the same way it focused the task analysis of ATIS/CVO systems.

Communications Problems in Marine Casualties: Development and Evaluation of Investigation, Reporting, and Analysis Procedures

The contribution of ineffective communications to marine casualties was studied. A standardized procedure was used to guide casualty investigations by Coast Guard investigators over a six-month period. Analyses of the resulting 589 casualty reports were conducted to characterize the extent and nature of communications problems in critical marine casualties. The results suggest that increased efforts to address these problems through improvements in operational procedures and training could reduce occurrences of such casualties. The study procedures were revised for future use in marine casualty investigations.

Defining the Operator Interface of a Snowplow Lane Tracking System from Field Interviews and Surveys

Maintaining lane position during low-visibility conditions can be a challenge for snowplow operators. Providing continuous and accurate lane position information to complement existing roadway cues may be the solution to increasing driver awareness. The first phase of a systemsbased approach to designing the operator interface for a snowplow lane tracking system is described. Through a systems-based approach, not only can the type of controls and displays to use for the operator interface be better defined, but the interface’s role and the amount, type, and presentation of information can be determined. In this first phase, ridealong interviews and an operator survey were used to identify factors affecting forward visibility and lane position in snowplow operations. More than 1,000 department of transportation snowplow operators from Iowa and Minnesota completed the survey. Ride-along drives showed that operators frequently lose sight of the forward roadway for brief periods and use several cues to adjust the lane position of their vehicles. Survey findings indicated that center and shoulder lines are helpful and intuitive cues for left- and right-wing plow operations. Additional findings suggest that operators need a flexible system that enables them to adjust alarm thresholds and that the operator interface should be designed as an aid rather than as a primary display. Because drivers do not have the visual resources for a dedicated display, a peripheral visual or haptic (tactile) display could be used to complement existing roadway cues.

Methodology for Evaluating a Simulator's Capability to Support Assessment of Mariner Proficiency

The goal of this project was to develop a structured process for evaluating the capability of simulators to support mariner performance assessment. In this approach, simulator evaluation objectives and criteria are based on performance-based mariner assessment requirements. The approach produces a simulator evaluation protocol that addresses four areas of simulator capability: (1) providing flexible exercise programming to the assessor; (2) replicating the characteristics of actual equipment; (3) simulating the operational conditions required to demonstrate the desired mariner performance; and (4) supporting thorough debriefing of the assessment candidate. A case study showed that our evaluation process was feasible. The process proved to be both sensitive and valuable in differentiating the capabilities of two simulators used to support mariner assessment objectives. This approach can be generalized to the evaluation of simulators of equipment used in other industries.

PREDICTING DRIVER BEHAVIOR USING ADVANCED TRAVELER INFORMATION SYSTEMS

As a part of the Intelligent Vehicle Highway System (IVHS), Advanced Traveler Information Systems (ATIS) will offer tomorrows drivers significantly expanded capabilities for getting where they want to go safely and efficiently. Vehicle-based navigation systems combined with information on highway conditions and services have the potential for improving driver performance. Though ATIS may offer considerable advantages, the system design must be consistent with the primary tasks of controlling and operating the vehicle. This paper describes an attempt to identify the likely interaction between what a driver must do to operate the vehicle safely while at the same time using the various ATIS systems. As such, it is an attempt to visualize what driving with these advanced systems will be like and to translate that vision into standard human factors task analytic techniques. Though a broad range of ATIS systems and functions were addressed in this project, this paper will address the macro-level task analyses that resulted from the examination of 165 tasks related to ATIS use.