# Eye-Tracking Investigation of the Train Driver's: A Case Study
## 2 Materials and Methods
### Eye-Tracking Technology
This video-coding procedure enabled the generation of a reference image from a segment of the scene (train cabin) camera video, and successive  
Figure 5: Area of interests (panels) identified in the EPJ 671 train cabin. clicks in the reference image at the identical position as the fixation within the superimposed scene video, once for each fixation in the data [46]. The Human-Machine Interaction Laboratory (HMI-LAB) of the University of Zilina is located at the University Science Park and is equipped with both software and hardware. The primary purpose of the HMI-LAB is to conduct research and testing related to human-machine interactions in a variety of settings. This lab was used to evaluate data for their final publication. The experiment was conducted to evaluate the behavior of a train driver during daylight on a chosen stretch of track. A climatized train cabin was utilized, free from any external interferences. A 51-year-old train driver, with 30 years of experience in regional, long-distance national, international, and railway transport, was engaged in the experiment; he had been absent from any category A or B railway accident (as classified by international railway safety standards) [9]. The train driver's task was to drive the train in the usual way. He wore eye-tracking goggles to record his interaction with the locomotive's controls and surroundings. He had no information about the variables to be evaluated during the measurement. He passed through 9 stations during his journey. Measurements on the same track were repeated 6 times, and the results presented in the paper are the average values of indicators from four selected types of stations. It should be emphasized that there are no standardized tasks that a driver must abide by. The two main regulations governing Slovak railways are the Regulation: Z1 Railway Operation Rules and Regulation: Performance of the driver's activities ZSSK V2. The Railway Operation Rules (Z1) is an extensive (more than 500 pages) set of regulations on transport activities and train operation on railways managed by ZSR. The Regulation on the Performance of Train Driver Activities ZSSK V2 details technological procedures and activities related to work activity and drive management of rolling stock. Despite their scope, neither regulation contains detailed processes and work procedures for the oper-ational actions of the train driver during the arrival of the train to the station/stop and the departure of the train from the station/stop. In order to obtain optimum raw data, SMI eye-tracking glasses were used to monitor the driver's visual attention. The following three steps were essential prior to measurement: establishing a connection between the eye-tracking glasses and the recording device (smartphone); configuring the experiment for the subject being tested in the recording device; and, completing the calibration process of the eye-tracking glasses and initiating the recording of the subject's gaze. The experiment has a critical analytical component that is designed to evaluate metrics that delineate the operation of the train and the interaction between the driver and the train's cabin control systems and panels during specialized operations. This research aims to elucidate the location, duration and frequency of the driver's gaze directed towards the areas of interest [47; 48]. The metrics to be established for each of the areas of interest in the cabin are as follows:  
* Dwell time is defined as the period of time from a participant's entry to their exit in a particular AOI. In some human factor research, dwell is referred to as glance or gaze duration. Dwell time is generally the aggregate of fixation and saccades durations during the stay in an AOI. The recorded dwell time for an AIO is contingent upon the AOI semantics and the participant's task. Dwell time is indicative of the attention paid to an AOI or the informative nature of said AOI. It may be presented in an absolute (time in milliseconds) or relative format (% of total time).