Human Systems Integration (HSI) in Complex Transportation Systems

Imagine being an air traffic controller at Boston Logan airport on a weekday morning, where you and your fellow controllers are responsible for ensuring the timely takeoffs and landings of 60 aircraft per hour. You are well trained and can normally handle such a workload without any problems. But today a thick fog has rolled in, making your out-the-window view useless for directing ground traffic. Under current Standard Operating Procedures, a ground-delay program for inbound traffic is initiated—with flight delay effects rippling across the day and the country—causing inconvenience for all involved. This scenario may one day have less impact on ATC through the integration of good engineering practice with human factors principles, a process known as Human Systems Integration.

Human factors and ergonomics are critical for the design and development of technology used by people in many contexts to improve both safety and efficiency. Although the terms are sometimes used interchangeably, human factors means the application of cognitive science to equipment displays, controls, and task performance, while ergonomics refers to workplace layout, biomechanics, and physiological considerations. The term human systems integration refers to the process of applying human factors and ergonomics to designing and developing systems that involve technologies, human operators, and organizations.

HSI is particularly important in transportation. Transportation systems tend to be large, complex human-machine systems involving and serving many different users and needs. Regardless of operating mode, the capital costs of transportation are high, and the public expects the highest level of safety feasible. Transportation systems affect the economies, politics, and lifestyles of the urban and/or rural communities and nations they serve. The success of HSI is dependent on how well human factors and ergonomics professionals communicate and collaborate with each other and with engineers and other disciplines, to satisfy the needs of multiple competing interests. Before installing, maintaining, and managing a system in the real world, they need to help identify opportunities, specify requirements, evolve designs, perform simulations and evaluations, and train the operators. To design an efficient system, not only must the human factors of the system and its users be considered but also those of its design process. This requires an eclectic team of professionals to communicate and collaborate via shared representations of goals and constraints.

The system concept that will likely bring relief from current ground-delay programs, by eventually replacing the out-the-window view with virtual displays, is an example of the Center’s move toward HSI. The SVT project, under the Advanced Surveillance and Communications Division, integrates understanding of human perception and information processing with electrical, systems, and software engineering to develop a novel air-traffic display. Such application of HSI principles promises to address not only air traffic but also congestion on U.S. highways. The increasing demands on our transportation system make acting upon the transportation enterprise with knowledge of human capability and decision making (and thus HSI) even more imperative.