Shipboard Automatic Identification System Displays: Meeting the Needs of Mariners -- Special Report 273 (2003)

Sponsored by the

TRB/Marine Board Committee for Evaluating Shipboard Display of Automatic Identification Systems

April 3–4, 2002, New Orleans, Louisiana

The Committee for Evaluating Shipboard Display of Automatic Identification Systems (AIS) sponsored a workshop on April 3–4, 2002, to solicit detailed information from experts and stakeholders about human factors and technical aspects of shipboard display systems. The workshop explored a number of issues related to future guidelines for AIS shipboard display parameters. It stressed the collection of current and accurate information and included suppliers, researchers, and ship operators with experience in using AIS or related systems. Each participant presented relevant views and expertise. The committee used the information and the subsequent discussions among participants to help analyze the problem and report results.

The presentations and discussions at the workshop are summarized in the following sections. Emphasis is given to the major points related to opportunities for use of AIS displays aboard vessels and limitations of the technology and human factors.

The workshop agenda with presenters and moderators identified, a list of workshop attendees, and a list of vendors who exhibited their equipment are provided at the end of this appendix.

Martha Grabowski, committee chair, introduced the committee and staff and presented an overview of the study goals and plans as well as the goals

of the workshop. The workshop was organized to make maximum use of invited experts and their experience to inform the committee members about the state of the art in technology for AIS displays, experience in previous tests and operations, related work in other fields, and pertinent studies and analyses.

Jorge Arroyo, from the U.S. Coast Guard (USCG), sponsor of this study, presented the group with a background of USCG’s development of AIS and its regulatory process for specifying carriage of AIS aboard vessels in U.S. waters. He pointed out that a notice of proposed rulemaking for AIS was under development and would be issued during summer 2002. So far no standards have been developed for AIS shipboard displays.

Panel I consisted of three presenters with committee member Robert Moore acting as facilitator:

• Holger Ericsson, Director of Marketing, Saab Transponder Tech AB (STT);

• George B. Burkley, Head, Applied Research Department at the Maritime Institute of Technology and Graduate Studies (MITAGS); and

• William Nugent, U.S. Navy Space and Naval Warfare (SPAWAR) Systems Center, San Diego, California.

The purpose of Panel I was to acquaint the committee with the limitations of AIS and display technology. To help the presenters focus on those limitations, they were each provided with a list of questions and areas of committee interest before the meeting. The material presented by Mr. Burkley and Mr. Nugent generally addressed the questions; Mr. Ericsson focused on the products offered by Saab. Mr. Moore stated at the start that AIS as now envisioned is a vehicle capable of transmitting a great deal of information and it is likely that its messaging capability will grow to fill its capacity. He asked the group to help focus the discussion on what needs the shipboard display of this information should meet and what displays would be the most beneficial to the mariner.

Mr. Ericsson stated that there are limits to AIS messaging capacities even though they are large. The preferred method of accommodating those lim-

its is to subdivide geographic regions into “cells,” each of which is served by an AIS “base station.” Of the three internationally agreed functions of AIS [ship-to-ship for collision avoidance, awareness by coastal states of vessels within their areas of interest, and use by a vessel traffic service (VTS) as a traffic management tool], the most data intensive is VTS use for traffic management. That information permits a conclusion that a major determinant of shipboard display requirements is the data intended to be provided shore-to-ship within a VTS area of responsibility. Mr. Ericsson concluded that there are implementation schemes for AIS that can protect against or compensate for the known limitations of AIS messaging capacity and that STT has significant experience with such implementations. Mr. Ericsson also presented a real-time demonstration of vessel situations in Swedish waters projected on an electronic charting and display information systems (ECDIS) chart to show one display option now available.

Mr. Burkley’s presentation focused on the differences between radar [specifically, automatic radar plotting aid (ARPA)] and AIS technologies as they relate to display issues. A conclusion supported by his material is that the integration of AIS data in an ARPA display increases the possibilities of confusion and misinterpretation, and he did not indicate that such integration would be desirable. Mr. Burkley concluded that AIS information should not be displayed on a radar screen because it would be more confusing than helpful to the mariner. Portable piloting units for AIS displays, separate from other shipboard displays, have become common and useful, even though Mr. Burkley believes that AIS and ARPA are not compatible.

Mr. Nugent presented many of the inherent capabilities of display technologies. The capabilities generally exceed those desirable for use aboard commercial vessels. He emphasized the need to focus on simplicity and clarity in order to limit training requirements and avoid the necessity for increased staffing. Mr. Nugent’s accounting of the Navy’s experiences proved that any level of complexity that is desired can be had and that there are situations in which added capabilities, at the cost of complexity, might be justified. He also provided information on display techniques and practices to be avoided, as learned from Navy and other military experiences. Mr. Nugent concluded that significant research work already exists on the topic of display design and that the integration of display technology with human factors, within the context of the intended application, is critical.

During the discussion session after the first panel presentations, several general points were made by presenters and participants:

• Even though AIS has high capacity for data exchange, limits are needed with regard to large geographical areas and large numbers of vessels that might participate.

• There is a need to manage the data on a display so that information will not overwhelm the operator—the use of overlays and lessons from the Navy’s symbology work may be valuable.

• Displays can handle certain combinations of system inputs, such as ECDIS and AIS, while other combinations may be problematic (ARPA and AIS).

• Any future requirements for AIS displays that might be contemplated need to be considered in the light of what other displays are required (or not required—such as ECDIS).

• AIS displays must be designed to meet end users’ needs.

• A variety of AIS user need categories must be sorted out—navigation, collision avoidance, situation awareness, voyage planning, vessel traffic management, and so forth.

• At present most AIS manufacturers are striving to meet International Maritime Organization standards with the addition of small graphical displays with minimal complexity.

• The AIS in any given waterway will be affected by the total capability of the traffic management system in that waterway.

Panel II consisted of three presenters with committee member John Lee acting as facilitator:

• Nadine Sarter, The Ohio State University;

• Kim Vicente, University of Toronto; and

• Edwin Hutchins, University of California, San Diego.

The purposes of Panel II were (a) to explore a range of human factors research and development work that might be applied to the problem of AIS

displays and (b) to acquaint the committee with human factors information relevant to shipboard and related bridge operations, the types of information systems used, and typical operator needs and capabilities. The panel was asked to comment on lessons from process control, cockpit information, and air traffic control situations that might apply to AIS. Questions included, What are recent findings related to interface alternatives (e.g., tactile vibration or sonification)? What human information processing limits might be critical to consider? What considerations with regard to the organization and combination of information might be useful to include? How should organizational, social, or teamwork considerations influence AIS interface designs?

Nadine Sarter presented highlights of her recent research in human factors in airline operations. She emphasized that any display should alert the operator to updated information and indicate where to find it. She also noted that many options are available for other than visual displays and that some of them may be preferable, especially for occasional warnings. The options include auditory displays, tactile channels (vibrations on skin) for getting the attention of the operator, and peripheral vision channels. These options may be especially useful for mode change detection. She concluded that there are automation and mode transformation lessons to be learned from aviation experience.

Kim Vicente presented relevant information from his research on integrated system designs for power plants and other control stations. He pointed out that too many detailed rules get in the way of sensible operator functions. When the operator must work to the rule, nothing gets done. Control systems must be designed for adaptation. Another point was that the biggest threats to safety are the unfamiliar and the unanticipated. He stressed that human cognitive ability is very adaptive and that complexity is in the eye of the beholder. His main conclusion was that tests and task analyses of which systems work best under real operating conditions shed much light on how to select an optimum design, and designers should not always display raw data but rather should develop the most useful interpretation of data. He also stressed that how people manage attention (when to look at what) has a huge impact on display design.

Ed Hutchins presented information on how human factors research can improve the design and safe operations of all systems. Key factors that must

be considered include how to monitor system status; what alerts work best; how to avoid skill atrophy; how to avoid overreliance on electronic displays when other, more direct, information is available (look out the window); how to avoid complacency; and how to build trust in the most accurate information. Another point is that the display designer must know what level of precision is needed for an operator to do a specific task—not what precision is possible. A final remark was that AIS should only provide information that an operator cannot get in another way.

Panel III consisted of three presenters with committee member Elizabeth Gedney acting as the facilitator:

• Lee Alexander, University of New Hampshire;

• Jeff McCarthy, San Francisco Marine Exchange; and

• Tom Hill, Master Mariner, SeaRiver Maritime.

The purpose of Panel III was to acquaint the committee with case studies involving AIS equipment and with successes and failures of tests or related systems developments. The last presenter discussed real operational factors on existing vessels on the basis of experience with AIS equipment that did not have any shipboard display. Information was sought from the presentations concerning how designs were selected and implemented, how user needs were evaluated, and what technical and human factors aspects were included.

Lee Alexander recommended that the committee take advantage of a number of past studies, tests, and reports that illustrate the gradual development of AIS technology and operations over a number of years. He emphasized that navigation and other important functions that AIS can facilitate should be addressed separately and with the end use in mind. For example, in ship-to-ship collision avoidance, AIS can supplement other data available to the mariner but must be tempered with knowledge about what vessels participate and what traffic management systems are in force. With regard to symbols that can be used on displays, standards (i.e., for ECDIS) have already been set for certain areas and situations. Therefore AIS can be and has been incorporated with ECDIS in some areas. For example, in the

St. Lawrence Seaway, AIS trials are beginning in July 2002, and several manufacturers will participate in these trials with three types of AIS and three types of ECDIS.

Mr. Alexander discussed his view of what factors are the most important for a suitable AIS display from the mariner’s perspective. He stated that the display should have a single background color scheme; it should be simplified in presentation, with only the critical information shown; the designer should strive for the most information with the least clutter; and the user should be able to select what information is important for the task at hand and set the display to provide that information.

The next presenter, Jeff McCarthy, described the history and lessons learned from an extensive AIS testing program over several years in the San Francisco Bay area.

The final presenter was Tom Hill, an experienced ship’s captain who has sailed worldwide for over 25 years on tankers for Exxon Shipping and now for SeaRiver Maritime. He described his experience from the standpoint of navigational equipment that he has used and how that experience might help in the selection of an AIS display system for the future. He has seen the rate at which new technologies become available accelerate in recent years, but the new technologies do not always increase operational effectiveness. He noted that radar does not usually work well when overlaid on ECDIS, and therefore operators shy away from that combination. He thinks that AIS has a better potential to overlay on ECDIS and provide more information. He thinks that AIS has the potential to do things that radar cannot (see around corners, improve target acquisition).

Captain Hill made the following observations in his presentation:

• AIS displays should have simple graphics and be easy to read—especially considering the aging mariner labor pool.

• Displays should filter out information that is not needed.

• Pilot carry-aboard equipment adds no benefit to the ship’s crew because it is not usually available to the rest of the bridge team.

• Too many mode changes are confusing and can lead to inoperability.

• Alarms must be integrated into the rest of a ship’s systems. New types of alarms (tactile) may be useful because they do not just add to the multitude of audible alarms that tend to all go off at once.

• Most ships are old and equipment is added piecemeal—it is hard to find the right place for everything.

• Reliability and simplicity are most important. If a system is too complex, it will not be used.

• Regulations and technology often are not compatible. Some equipment might help operations but not help meet regulations (ships with ECDIS still must keep hand records on paper charts to satisfy regulators).

During the question and answer session for this panel, several issues were discussed.

• Many participants believe that AIS must be better designed to meet user needs and designers must better understand what information and displays will most improve overall safety of navigation.

• The notion of not having an AIS display was discussed. The questions that should be addressed are, How much should AIS be relied on? How specifically does USCG need to require a system?

• AIS is needed the most when conditions are bad and looking out the window is not the best option.

• Simplicity of operation and display should be stressed, and the importance of operator training should be recognized.

Panel IV consisted of four presenters with committee member Douglas Grubbs acting as the facilitator:

• Benny Pettersson, Swedish Maritime Administration and Passenger Vessel Pilot;

• Allison Ross, Bay Pilot with the Association of Maryland Pilots;

• Mark Stevens, Inland Barge Operator with Ingram Barge, Inc.; and

• Jorge Viso, Pilot with Tampa Bay Pilots Association.

The purpose of this panel was to present and discuss the needs of various operators for AIS displays to aid in making the best navigational decisions. The participants were asked to discuss pitfalls that should be avoided, les-

sons that have been learned from recent tests and operations, and how overall vessel operational tasks might change with the introduction of AIS. The panel members include mariners from key industry sectors who will be directly affected by the introduction of AIS displays aboard vessels.

Captain Pettersson described the status of AIS usage in Europe, especially Sweden. He stated that AIS does not replace existing navigation inputs (radar, etc.). However, AIS can give more accurate data than can radar, and it can give some data that radar cannot. In some modes, radar gives the wrong information, especially with regard to turning vessels and their heading, and this can be corrected by AIS. In Swedish tests it has been shown that minimal symbols on an electronic chart can give intuitive information about ship position in a turn. Over a few years of Swedish tests and operations with AIS, the pilots and mariners have become comfortable with the technology and confident of the information provided to them. This trust is hard to gain but is a highly important factor.

Captain Ross indicated that in Chesapeake Bay, security concerns are fast changing the pilots’ operational procedures and the way all technologies (including AIS) are being used. She stressed that the best AIS display should present the basic data in a simple way and in one place so that the mariner need not go from place to place on the bridge to get information. There is too much ARPA and other clutter already on most bridges, and that should not be increased.

Mark Stevens presented the inland waterways situation and its unique needs for AIS-type data and displays. He stated that it is important to have an easy-to-operate system that can be integrated into currently used systems. Inland tug operators do not usually have radar, do not plot charts, and do not need latitude and longitude information. However, AIS displays should integrate easily into electronic charts that are in use with minimal clutter of data. Systems must also work on all 25,000 miles of inland waterways and on 4,500 operating vessels. Designers must recognize that inland vessels are confined in available space and have limited time to make navigational decisions. Some electronic charts are problematic because of frequent water level changes. Operators also need very simple displays directed to their operating environment.

Captain Viso described the recent test usage of AIS in Tampa Bay by ship’s pilots, other vessel operators, and traffic managers. Pilots have used carry-

aboard units since 1998. The system displays a chart with own-ship and other vessel data overlaid. The vessel traffic system can pick up ships up to 70 miles offshore. Environmental data (PORTS) is also displayed as a popup on the AIS. Text messages can be sent between vessels. AIS has been a useful tool for traffic management in Tampa Bay, which has a long, narrow, and restricted channel. In their 3.5 years of experience Tampa pilots have verified the usefulness of AIS and now can trust the equipment in fog and storms. Most pilots now use it to look over the entire bay—not just in a passing situation. They have verified what information is most important to transmit and display, and they have become strong proponents of its benefits. Captain Viso stressed that AIS has proved most useful as a planning tool for meeting situations. He noted that an important future improvement would be harmonization of formats with other systems.

Committee Chair Martha Grabowski led the concluding discussion of all participants at the workshop. The USCG representative noted that USCG is in the process of rulemaking on AIS carriage requirements and that the public can bring any concerns to its attention through its website: www. uscg.mil/vtm.

Several comments were made in general to the committee and all other participants. One was that the committee should carefully separate policy on early AIS development from that needed to implement an up-to-date system. Another pointed out that all affected nations should work together on international standards rather than implementing individual national standards. Another participant noted that committee members should see some actual systems in operation.

Some concluding main points from the workshop follow:

• Available AIS units can display a large range and amount of information, including target IDs, traffic situations, navigation predictions, and depictions. They have been integrated with ECDIS in several tests. However, integration with ARPA displays appears to be problematic.

• Portable AIS units have been most widely used (by pilots) in the United States, and they have not been integrated with any existing bridge systems.

• Significant research by the U.S. Navy on display systems can inform future design of AIS displays and most appropriate symbols.

• There is no universal agreement on the amount of information that should be included in an AIS shipboard display. There is general concern about too much information or clutter that would make for operator confusion and inhibit interpretation. Display information should be matched to the mariner’s tasks and to the operational needs for navigation safety or other appropriate functions.

WORKSHOP AGENDA

National Academy of Sciences

Transportation Research Board

COMMITTEE FOR EVALUATING SHIPBOARD DISPLAY OF

AUTOMATIC IDENTIFICATION SYSTEMS

Hyatt Regency

New Orleans, Louisiana

April 3–4, 2002

Meeting Objectives

• Receive panel presentations relative to the committee’s charge

• Examine AIS display systems being developed by various manufacturers

OPEN SESSION

Wednesday, April 3, 2002

Thursday, April 4, 2002

WORKSHOP ATTENDEES

COMMITTEE FOR EVALUATING SHIPBOARD DISPLAY OF

AUTOMATIC IDENTIFICATION SYSTEMS

Hyatt Regency

New Orleans, Louisiana

April 3–4, 2002

Committee and Staff

Sponsor

Speakers

AIS Manufacturers

Other Attendees