Eye-Activity Measures of Fatigue and Napping as a Fatigue Countermeasure

Details

• Corporate Creators:
  Trucking Research Institute
• Corporate Contributors:
  United States. Office of Motor Carrier Research and Standards
• Subject/TRT Terms:
  • Commercial drivers
  • Physiological fatigue
  • Sleep
  • Eye movements
  • Highway safety
  • Trucking safety
  • Alertness
  • Simulation
  • Eyelids
  • Motor vehicle drivers
  More +
• Publication/ Report Number:
  FHWA-MC-99-028
• Resource Type:
  Tech Report
• Right Statement:
  Public Domain
• Geographical Coverage:
  United States
• Edition:
  Final Report
• Corporate Publisher:
  United States. Federal Highway Administration. Office of Motor Carriers
• Abstract:
  This study investigated (1) the potential use of an eye tracking system for detecting reduced driver alertness and (2) the impact of prophylactic napping on driver performance and alertness. The study used traditional behavioral and physiological measures of alertness. In addition, an unobtrusive eye tracker attached to the simulator structure was used to measure eye and eyelid behavior. The results showed clear time-of-day (TOD) and time-on-task (TOT) effects for the following eye closure measures: Partial closures during fixations, speed of slow eyelid closure (SEC), blink duration, and blink frequency. Eye closures during fixations exhibited the following alertness monitoring characteristics: 1) the cyclic phases of a driver experiencing brief lapses of alertness and recovery; 2) a continuous decline ultimately leading to an off-road simulator crash; 3) an early warning potential of 10 minutes or more; 4) a dramatic decline in the measure beginning 2-3 minutes before an off-road simulator crash. SEC events and blink duration showed sustained increases with TOT and TOD. A preliminary algorithm for detecting level of alertness was developed. This algorithm uses the eye closure measure in a way that includes partial eye closures during fixations, blink frequency, blink duration, and speed of eye closure effects. The 3-hour afternoon nap increased the subjects' nighttime alertness and improved driving performance. Beneficial effects of the afternoon nap on nighttime driving performance included significantly fewer crashes, shorter run completion times, and smaller standard deviations of lane position. The results provide evidence that the 3-hour afternoon nap was effective in reducing sleepiness levels during the following night and suggest that prophylactic naps may be more beneficial than recuperative naps during all-night driving situations.
• Format:
  PDF
• Funding:
  DTFH61-96-00022
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/92809/dot_92809_DS1.pdf
• File Type:
  [PDF - 5.59 MB]
• Collection(s):
  Federal Highway Administration
• Main Document Checksum:
  urn:sha-512:15ad1e5561f9d3f0f3d9392859dd0936015f6404e1ed2814a17e110ba3fa84c8676bc68b7950f1c43b0e8250e974fdf1732359d8e00d8e4c3f4c0cccb53659ae