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HSI Resources: Tools

Eye Tracking

An eye tracking diagram.
Image Source:

What is eye tracking?

Eye tracking is the process of capturing what a person is looking at, or the direction where he/she is looking, using sensors mounted on a nearby work surface or a head harness (as the illustration at right shows).

 How is eye tracking used?

Eye tracking can be used  to evaluate user interfaces by studying user behavior. For instance, when OEMs are developing new technologies and displays, eye tracking can be used to understand where the user is looking. Direction of gaze can indicate where a viewer is paying attention, but it does not necessarily mean the viewer is paying attention.

Eye trackers can be used to learn how operators scan scenes (such as in a simulator) and displays. The direction of gaze at first glance and areas of the scene where the eyes linger and return, may all  indicate areas the viewer is interested in. 

Eye trackers can also be used to support performance. For example, eye tracking devices have been integrated with driver-assistance systems to improve safety in cars and trucks.

A heat map.
Image Source: Virginia Commonwealth University

Results of studies using an eye tracker can help improve the design of individual interfaces and entire cabs.

heat map image can show the location and amount of attention paid to items of interest, such as a web site page,  (see image at right). Gaze direction provides insight into what information may be the current focus of attention, particularly in situations in which a person is performing a visual search .


What is a simulator?

A simulator is a partial or complete workstation environment with operating features and displays that are very close to the actual workstations operators use in real life. The Cab Technology Integration Laboratory (CTIL) simulator at the Department of Transportation's Volpe Center in Cambridge MA creates realistic conditions to train and certify operators.

How is a simulator used?

A conductor using a train simulator.
Image Source: Department of Transportation

Video on screens shows what an operator would see through cab windows, creating a true-to-life work setting. Operators can be presented with a wide range of conditions and circumstances.  Routes and situations can be run multiple times without risk. The video used in this eLearning site's Attention Game shows how the simulator experience can realistically  challenge operator attention.