Human Factors Laboratory

Purpose: The purpose of the Human Factors Laboratory is to further the understanding of highway user needs so that those needs can be incorporated in roadway design, construction, repair, and improvement. All of Federal Highway Administration's strategies for improving safety and enhancing operations throughout the highway transportation system benefit from the appropriate consideration of user needs. Human factors studies consider driver, pedestrian and special user needs and capabilities.

Laboratory Equipment and Facilities: The Human Factors Laboratory is comprised of several facilities.

• Highway Driving Simulator has been and continues to be used for a variety of behavioral studies and visualization projects for the FHWA and other stakeholders. The simulator consists of a full automobile chassis surrounded by a cylindrical projection screen (radius of 8.5 feet, or 2.6 meters) onto which five projectors render a seamless 240° field–of–view of high quality computer generated highway scenes. The simulator has a three degree–of–freedom motion–based system that provides pitch (for acceleration and braking), sway (for curve forces), and heave (for bumps) cues in concert with the visual environment. The simulator's sound system provides engine, wind, and tire noises, and other environmental sounds. Custom software is developed in–house to provide a scalable, extensible, flexible, and evolvable environment for achieving high fidelity, real–time, fully interactive, driving simulations. Recent studies conducted in the simulator have examined:

  • The effectiveness or various roadway markings for aiding drivers in navigating rural mountain roads at night.

  • Signing and markings for roundabouts.

  • Driver comprehension of novel intersection and interchange designs.

  • Variability in driver responses to traffic signal changes.

• Field Research Vehicle is an instrumented 2007 Sport Utility Vehicle used to collect driver behavior and performance data on actual roadways. The vehicle is equipped with a state–of–the–art eye–tracking system that consists of two infrared (IR) light sources and three face cameras mounted on the dashboard of the vehicle. The cameras and light sources are small in size, and are not attached to the driver in any manner. The face cameras are synchronized to the IR light sources, and are used to determine the head position and eye gaze of the driver. The vehicle also records GPS position, vehicle speed, vehicle acceleration, and data input by an experimenter in real time. Recent studies conducted in the vehicle have examined:

  • Driver visual behavior in the presence of digital billboards.

  • Sign conspicuity in the Right–of–Way.

• Highway Sign Design and Research Facility enables researchers to present traffic signs to participants in a controlled environment. In the development of new traffic signs, it is important to determine the maximum distance at which the sign can be understood. To this end, signs are " zoomed" such that the appearance approximates that of driving towards the sign at a specified speed. The size of the zoomed image at the moment the sign is recognized is then used to approximate the sign's recognition sight distance. The sign research facility is also used for a variety of other studies of sign comprehension. Precise control of sign display duration, "zoomed" image speed, and the measurement of participant reaction time are achieved through computer control. Research signs are developed using the same software applications used by state departments of transportation, thus ensuring that signs presented in the laboratory accurately mimic signs as they would appear in the field. Recent studies conducted in the sign lab have examined:

  • Driver comprehension of new and alternative sign symbols.

  • Evaluation of diagrammatic freeway guide signs.

  • Navigational signing for roundabouts.

  • Sign comprehension for combination high occupancy vehicle and toll lanes.

• MiniSim^TM driving simulator is a part–task simulator consisting of a quarter cab set up that includes an adjustable driver's seat, driver controls (pedals, steering wheel, etc.), meter cluster (speedometer, etc.), 42" forward display screen, and a touchscreen in– vehicle display. In partnership with the National Highway Traffic Safety Administration (NHTSA), the MiniSim is used for various studies of in–vehicle distraction studies (e.g., MP3 use while driving) and other infrastructure–related studies that do not require the full immersive HDS simulation environment. The MiniSim affords both FHWA and NHTSA the ability to conduct low–cost studies that may answer specific questions or act as a preliminary research phase prior to a larger scale simulation or on road research project.

• Data Analysis Facility is used by researchers for the review and analysis of analog and digital imagery and data recorded from human factors experiments and field observational studies. The facility provides researchers with a number of databases, statistical and video analysis software tools.