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Publication Number: FHWA-HRT-04-134
Date: December 2005

Enhanced Night Visibility Series, Volume III: Phase II—Study 1: Visual Performance During Nighttime Driving in Clear Weather

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Figure 1. Photo. Pedestrian in black clothing. This photograph shows one of the objects used in the study. It is a side view of a person dressed in black standing against a plain background. The person is wearing a ski cap with face mask, protective glasses, jacket, pants, boots, and gloves. Back to Figure 1.

Figure 2. Photo. Cyclist in black clothing. This photograph shows one of the objects used in the study. It is a side view of a person dressed in black riding a dark-colored mountain bike against a plain background. The person is wearing a ski cap with face mask, protective glasses, jacket, pants, boots, and gloves. Back to Figure 2.

Figure 3. Photo. Cyclist in white clothing. This photograph shows one of the objects used in the study. It is a side view of a person riding a mountain bike with a bright orange frame against a plain background. The person is wearing a white short-sleeved shirt over a black long-sleeved shirt, white pants, a black ski cap with face mask, protective glasses, black boots, and gloves. Back to Figure 3.

Figure 4. Photo. Pedestrian in white clothing. This photograph shows one of the objects used in the study. It is a side view of a person wearing a white short-sleeved shirt over a black long-sleeved shirt, white pants, a black ski cap with face mask, protective glasses, black boots, and gloves. The person is standing against a plain background. Back to Figure 4.

Figure 5. Photo. Child’s bicycle. This photograph shows one the objects used in the study. It is a side view of a child’s bicycle propped upright against a plain background. The bicycle has a yellow frame, pink tire rims, and white seat, tires, and pedals. Back to Figure 5.

Figure 6. Photo. Tire tread. This photograph shows one of the objects used in the study. It is an intact circular tire tread with the sidewall removed. The tire tread is lying on its side against a plain background. Back to Figure 6.

Figure 7. Diagram. Data collection display screen. The graphic shows a sample display screen used to record the data collected during an on-road trial. The first section identifies the driver and passenger by participant ID, age, and gender. The next section describes the trial setup, including the VES, target order, day, participant number, the output file name, and the specific experiment being conducted. The final section allows the experimenter to select the target used in the trial and records the driver and passenger detection and recognition distances. Back to Figure 7.

Figure 8. Photo. Five or three UV–A + halogen low beam. The photo shows two halogen low beam lamps and five UV–A lamps attached to the front of an experimental SUV on a modular light rack.
Back to Figure 8.

Figure 9. Photo. High output halogen or halogen high beam. The photo shows two high output halogen lamps and two halogen high beam lamps attached to the front of an experimental pickup truck on a modular light rack. One high output halogen and one halogen high beam lamp are housed together on the right front of the vehicle, and the other pair is housed together on the left front of the vehicle. Back to Figure 9.

Figure 10. Photo. Hybrid UV–A + high intensity discharge. The photo shows two hybrid UV–A lamps and two high intensity discharge lamps attached to the front of an experimental SUV on a modular light rack. The high intensity discharge lamps are mounted on the far right and far left front, and the hybrid UV–A lights are mounted adjacent to them toward the center of the vehicle. Back to Figure 10.

Figure 11. Photo. Halogen low beam-low profile with infrared thermal imaging system. The photo shows the front of the experimental sedan used in the study. The sedan is equipped with standard halogen low beam lamps. In the center of the front grille, there is a circular opening for the infrared camera, indicating the presence of the infrared thermal imaging system. Back to Figure 11.

Figure 12. Photo. Smart Road. The photo is an aerial view of a section of the Smart Road. The section of road is fairly straight with one gradual curve. The photo shows that there are no other structures in the immediate vicinity. Back to Figure 12.

Figure 13. Diagram. Locations where the objects were presented for Study 1. The diagram shows the entire course of the Smart Road driven by participants during the study. The road is depicted as being fairly straight with one gradual curve toward the top. There is a turnaround loop at each end of the road. The top turnaround is in the upper left corner of the diagram; the bottom turnaround is in the lower right corner, indicating that there is a grade. A legend contains an arrow labeled “Object Location.” There are six arrows along the side of the road indicating the six locations where objects were presented. Locations 1, 2, and 3 are on one side of the road, indicating that a driver would see objects placed there during the drive from the top to the bottom of the road. Locations 4, 5, and 6 are on the opposite side of the road from the first three locations, indicating that a driver would see objects placed there during the drive from the bottom of the road to the top of the road. Location 4 is opposite location 2, and location 5 is nearly opposite location 1. Location 6 is on the same side as locations 4 and 5, but it is farther up the road near the top turn. Locations 1, 2, 3, 4, and 5 are all grouped toward the middle segment of the course. Location 3 is on the end toward the bottom turnaround. The diagram shows that all locations are on straight sections of the road. Back to Figure 13.

Figure 14. Bar graph. Results on detection distances for the interaction: VES by Age. The graph is titled “Detection Distances for the VES by Age Interaction for the Clear Condition.” The Y-axis shows the mean detection distance in feet. The X-axis includes each of the 12 vision enhancement systems (VESs) and indicates that HLB is the baseline. Three bars are presented for each of the VESs, representing the three age groups: young, middle, and older. Standard error bars are also provided for each graph bar. For the younger drivers, the detection distances ranged from approximately 550 to 730 feet. Middle-aged drivers detected objects in a range of approximately 510 to 760 feet. The older drivers’ detection distances ranged from approximately 450 to 590 feet. Younger and middle-aged drivers had the longest detection distances with the IR–TIS. Older drivers had the longest detection distances with the hybrid UV–A + HLB. The HID provided the shortest detection distances for all three age groups. Standard error bars for each set of VES groups are generally comparable. Back to Figure 14.

Figure 15. Bar Graph. Results on detection distances for the interaction: Object by Age. The graph is titled “Detection Distances for the Object by Age Interaction for the Clear Condition.” The Y-axis shows the mean detection distance in feet. The X-axis includes each of the nine objects used in the study. Three bars are presented for each of the objects, representing the three age groups: young, middle, and older. Standard error bars are also provided for each graph bar. For the younger drivers, the detection distances ranged from approximately 205 feet (tire tread) to approximately 900 feet (cyclist in white clothing). The detection distances for the middle-aged group ranged from approximately 210 feet (tire tread) to approximately 850 feet (perpendicular pedestrian in white clothing and the static pedestrian in white clothing). The detection distances for the older drivers ranged from approximately 205 feet (tire tread) to 800 feet (static white pedestrian). In general, older drivers were not able to detect objects as far as the middle and younger age groups. The younger and middle age groups had similar detection distance for all the objects except the white cyclist and the white parallel pedestrian; the younger age group had approximately 80 feet greater detection distance for both objects. Standard error bars for each set of object groups are generally comparable, with the tire tread producing a slightly smaller standard error than other objects. Back to Figure 15.

Figure 16. Bar graph. Results on recognition distances for the interaction: Object by Age. The graph is titled “Recognition Distance for the Object by Age Interaction for the Clear Condition.” The Y-axis shows the mean recognition distance in feet. The X-axis includes each of the nine objects used in the study. Three bars are presented for each of the objects, representing the three age groups: young, middle, and older. Standard error bars are also provided for each graph bar. The younger drivers’ recognition distances ranged from 175 feet (tire tread) to 795 feet (static pedestrian in white clothing). The middle age group had recognition distances ranging from 175 feet (tire tread) to 710 feet (static pedestrian and perpendicular pedestrian in white clothing). The older age group had recognition distances ranging from 170 feet (tire tread) to 705 feet (static pedestrian in white clothing). The older age group had the shortest recognition distances for all objects. The younger and middle age groups had similar recognition distances for the cyclist and pedestrians dressed in black. However, the younger age group had approximately 40 to 100 feet greater recognition distances for the cyclist and pedestrians dressed in white. Standard error bars for each set of object groups are generally comparable, with the recognition distance of the tire tread producing a slightly smaller standard error than other objects. Back to Figure 16.

Figure 17. Bar graph. Results on detection distances for the interaction: VES by Object: Pedestrians and cyclists in white clothing. The graph is titled “Detection Distances for the VES by Object Interaction for the Clear Condition.” The Y-axis shows the mean detection distance in feet. The X-axis includes the twelve different VESs evaluated in the study. Four bars are presented for each VES, representing the following four objects: cyclist with white clothing, parallel pedestrian with white clothing, perpendicular pedestrian with white clothing, and the static pedestrian with white clothing. Standard error bars are also provided for each graph bar. Following are the approximate ranges of detection distances for each object: cyclist with white clothing ranged from 680 feet with the HID to 920 feet with the five UV–A + HLB; parallel pedestrian with white clothing ranged from 705 feet with the HID to 895 feet with the five UV–A + HLB; perpendicular pedestrian with white clothing ranged from 710 feet with the hybrid UV–A + HID to 950 feet with the IR–TIS. Standard error bars for each set of VES groups are generally comparable, with the detection distance for IR–TIS producing a slightly larger standard error than other VESs. Back to Figure 17.

Figure 18. Bar graph. Results on detection distances for the interaction: VES by Object: child’s bicycle, tire tread, and pedestrians and cyclists in black clothing. The graph is titled “Detection Distances for the VES by Object Interaction for the Clear Condition.” The Y-axis shows the mean detection distance in feet. The X-axis includes the 12 different VESs evaluated in the study. Five bars are presented for each VES, representing the following five objects: cyclist in black clothing, parallel pedestrian in black clothing, perpendicular pedestrian in black clothing, child’s bicycle, and tire tread. Standard error bars are also provided for each graph bar. The approximate ranges of detection distances for each object are as follows: cyclist in black clothing ranged from 410 feet with the five UV–A + HID to 805 feet with the IR–TIS; parallel pedestrian in black clothing ranged from 250 feet with the five UV–A + HID to 650 feet with the IR–TIS; perpendicular pedestrian in black clothing ranged from 260 feet with the HID to 650 feet with the IR–TIS; tire tread ranged from 160 feet with the IR–TIS to 250 feet with the three UV–A + HLB. The smallest detection distance for the child’s bicycle was approximately 350 feet with the IR–TIS. The farthest detection distance for the child’s bicycle was approximately 450 feet. The five UV–A + HLB, three UV–A + HLB, hybrid UV–A + HLB, HLB, five UV–A +HID, and the hybrid UV–A + HID all approximated a 450-ft detection distance for the child’s bicycle. When comparing the detection distances obtained using IR–TIS to the detection distances obtained using HLB–LP, it is clear the detection distances of the dynamic objects (pedestrians and cyclist dressed in black) was greater while using the IR–TIS. The IR–TIS increased the detection distance of the cyclist in black clothing by approximately 300 feet, the parallel pedestrian in black clothing was increased approximately 350 feet, and the perpendicular pedestrian in black clothing was increased approximately 330 feet as compared to HLB–LP. The detection distances of the static objects (child’s bicycle and tire tread) were either slightly greater or the same while using HLB–LP as compared to IR–TIS. The detection distance for the child’s bicycle was approximately 50 feet larger when using HLB–LP than when using IR–TIS. The detection distance for the tire tread was not significantly different when the IR–TIS and HLB–LP were compared. Standard error bars for each set of VES groups are generally comparable, with a few exceptions. The standard error for tire tread detection is generally smaller than other objects and the standard error bars for detection while using IR–TIS for all the objects in black clothing are larger than for detection with other VESs. Back to Figure 18.

Figure 19. Bar graph. Results on recognition distances for the interaction: VES by Object: Pedestrians and cyclists in white clothing. The graph is titled “Recognition Distances for the VES by Object Interaction for the Clear Condition.” The Y-axis shows the mean recognition distance in feet. The X-axis includes the 12 different VESs evaluated in the study. Four bars are presented for each VES, representing the following four objects: cyclist with white clothing, parallel pedestrian with white clothing, perpendicular pedestrian with white clothing, and the static pedestrian with white clothing. Standard error bars are also provided for each graph bar. Following are the approximate ranges of recognition distances for each object: cyclist with white clothing ranged from 500 feet with HID to 750 feet with five UV–A + HLB; parallel pedestrian with white clothing ranged from 620 feet with HID to 805 feet with five UV–A + HLB; perpendicular pedestrian with white clothing ranged from 625 feet with HID to 800 feet with five UV–A + HLB; static pedestrian with white clothing ranged from 630 feet with hybrid UV–A + HID to 820 feet with three UV–A + HLB. The standard error bars for each set of VES groups are generally comparable. Back to Figure 19.

Figure 20. Bar graph. Results on recognition distances for the interaction: VES by Object: child’s bicycle, tire tread, and pedestrians and cyclists in black clothing. The graph is titled “Recognition Distances for the VES by Object Interaction for the Clear Condition.” The Y-axis shows the mean recognition distance in feet. The X-axis includes the 12 different VESs evaluated in the study. Five bars are presented for each VES representing the following five objects: cyclist in black clothing, parallel pedestrian in black clothing, perpendicular pedestrian in black clothing, child’s bicycle, and tire tread. Standard error bars are also provided for each graph bar. The approximate ranges of recognition distances for each object are as follows: cyclist in black clothing ranged from 340 feet with three UV–A + HID to 525 feet with hybrid UV–A + HLB, parallel pedestrian in black clothing ranged from 210 feet with five UV–A + HID to 495 feet with IR–TIS, perpendicular pedestrian in black clothing ranged from 205 feet with five UV–A + HID to 525 feet with IR–TIS, and child’s bicycle ranged from 300 feet with IR–TIS to 410 feet with both the three and five UV–A + HLB. The shortest recognition distance for the tire tread was with IR–TIS at approximately 125 feet. The longest recognition distances for the tire tread were with the hybrid UV–A + HLB, three UV–A + HLB, and the five UV–A + HLB. The range for these recognition distances with the various HLBs was approximately 195 feet to 200 feet. Recognition distances for the pedestrians and cyclist in black clothing were greatest with the IR–TIS. However, the IR–TIS had the shortest recognition distances for the static objects (child’s bicycle and tire tread). The standard error bars for each set of VES groups are generally comparable with the standard error bars for recognition distance of objects in black clothing for IR–TIS being slightly larger. Back to Figure 20.

Figure 21. Bar graph. Bonferroni post-hoc results on detection and recognition distances for the main effect: age (means with the same letter are not significantly different). The graph is titled “Detection and Recognition Distances by Age Group for the Clear Condition.” The Y-axis shows the mean distance in feet. The X-axis includes the three age groups represented in the study: young, middle, and older. There are two bars for each age group, one representing the detection distance and the other representing the recognition distance. Letters above each bar note the groupings for the means (means with the same letter are not significantly different) based on the Bonferroni results. Standard error bars are also provided for each graph bar. The approximate detection distances for the three age groups were as follows: young equals 605 feet, middle equals 595 feet, and older equals 525 feet. Detection distance for the younger age group was significantly different than detection distance for the older age group. The approximate recognition distances for the three age groups were as follows: young equals 520 feet, middle equals 495 feet, and older equals 450 feet. Recognition distance for the younger age group was significantly different than recognition distance for the older age group. The standard error bars are comparable across age groups. Back to Figure 21.

Figure 22. Bar graph. Bonferroni post-hoc results on detection and recognition distances for the main effect: VES (means with the same letter are not significantly different). The graph is titled “Detection and Recognition Distances by VES for the Clear Condition.” The Y-axis shows the mean distance in feet. The X-axis includes the 12 VESs evaluated in the study. There are two bars for each VES, one for detection distance and one for recognition distance. Letters above each bar note the groupings for the means (same letter are not significantly different) based on the Bonferroni results. Standard error bars are also provided for each graph bar. Detection distances ranged from approximately 500 feet with HID to 690 feet with IR–TIS. Detection distances with the IR–TIS were significantly different than the other 11 VESs. There was a significant difference between the HLB–LP and all other HLB configurations, with the HLB–LP having the shortest detection and recognition distances at approximately 520 feet and 450 feet, respectively. The hybrid UV–A + HLB, five UV–A + HLB, and three UV–A + HLB were significantly different than the corresponding HID configurations, with the HLBs increasing detection distances. Recognition distances ranged from approximately 420 feet with HID to 550 feet with five UV–A + HLB. There were no significant differences in recognition distance across the IR–TIS, five UV–A + HLB, three UV–A + HLB, hybrid UV–A + HLB, and HLB. However, these five VESs had significantly greater recognition distances than all the HID configurations and the HLB–LP. The standard error bars are comparable across VESs. Back to Figure 22.

Figure 23. Bar graph. Bonferroni post-hoc results on detection and recognition distances for the main effect: object (means with the same letter are not significantly different). The graph is titled “Detection and Recognition Distances by Object for the Clear Condition.” The Y-axis shows the mean distance in feet. The X-axis includes the nine objects used in the study. There are two bars for each object, one for detection distance and one for recognition distance. Letters above each bar note the groupings for the means (means with the same letter are not significantly different) based on the Bonferroni results. Standard error bars are also provided for each graph bar. Detection distances for the pedestrians and cyclist in white clothing ranged from approximately 805 feet to 845 feet, and the differences between them were not significant. Detection distances for the pedestrians and cyclists in black clothing ranged from approximately 355 feet for the parallel pedestrian to approximately 520 feet for the cyclist. The cyclist in black was significantly different than the parallel and perpendicular pedestrian in black. Detection distances of the objects in white were significantly different than all of the objects dressed in black. The detection distance for the child’s bicycle (approximately 425 feet) was significantly different than all other objects, as was the detection distance for the tire tread (approximately 205 feet). Recognition distances for the pedestrians and cyclist in white ranged from approximately 650 feet for the cyclist to approximately 730 feet for the static pedestrian; recognition distance for the cyclist in white was significantly different than the other objects in white. Recognition distances for the cyclist and pedestrians in black ranged from approximately 300 feet for the parallel pedestrian to approximately 450 feet for the cyclist; recognition distance for the cyclist in black was significantly different than distances for the pedestrians in black. All of the objects in white had significantly greater recognition distances than the objects in black. The recognition distance for the child’s bicycle (approximately 380 feet) was significantly different than all other objects, as was the recognition distance for the tire tread (approximately 175 feet). Standard error bars are comparable across objects with the error bars for the tire tread being slightly smaller than those for the other objects. Back to Figure 23.

Figure 24. Bar graph. Bonferroni post-hoc results on the ratings evaluating detection for the main effect: VES (means with the same letter are not significantly different). The graph is titled “Statement 1: This vision enhancement system allowed me to detect objects sooner than my regular headlights.” The Y-axis shows the mean rating for the statement and starts at 1 (“strongly agree”) and ends at 7 (“strongly disagree”). A lower rating indicates a more desirable system. The X-axis includes the 12 VESs and indicates that HLB is considered the baseline. Standard error bars are also provided for each graph bar. The IR–TIS has the lowest rating of approximately 1.4 and is significantly different than all other VESs. There was no significant difference between the remaining 11 VESs. The ratings for the other VESs ranged from approximately 2.5 for five UV–A + HLB to 3.3 for HID. The mean rating for HLB (baseline) was approximately 3.2. The standard error bars are comparable across the VESs. Back to Figure 24.

Figure 25. Bar graph. Bonferroni post-hoc results on the ratings evaluating recognition for the main effect: VES (means with the same letter are not significantly different). The graph is titled “Statement 2: This vision enhancement system allowed me to recognize objects sooner than my regular headlights.” The Y-axis shows the mean rating for the statement and starts at 1 (“strongly agree”) and ends at 7 (“strongly disagree”). A lower rating indicates a more desirable system. The X-axis includes the 12 VESs and indicates that HLB is considered the baseline. Standard error bars are also provided for each graph bar. The IR–TIS received the lowest rating of approximately 2. The three UV–A + HID received the highest rating of approximately 3.4 (still in the “agree” range). The difference between the IR–TIS and three UV–A + HID was significant. The rating for three UV–A + HID was also significantly different than the ratings for five UV–A + HLB, which received a rating of approximately 2.5. The mean rating for the HLB (baseline) was approximately 3.1, and the only VES it was significantly different from was IR–TIS. The standard error bars are generally comparable across the VESs. Back to Figure 25.

Figure 26. Bar graph. Bonferroni post-hoc results on the ratings evaluating visual discomfort for the main effect: VES (means with the same letter are not significantly different). The graph is titled “Statement 5: This vision enhancement system did not cause me any more visual discomfort than my regular headlights.” The Y-axis shows the mean rating for the statement and starts at 1 (“strongly agree”) and ends at 7 (“strongly disagree”). A lower rating indicates a more desirable system. The X-axis includes the 12 VESs and indicates that HLB is considered the baseline. Standard error bars are also provided for each graph bar. The IR–TIS received the highest rating of approximately 3.4 (still in the “agree” range), but the rating was not significantly different than HHB, five UV–A + HID, three UV–A + HID, HID, or HLB–LP. The ratings for the other 11 VESs were not significantly different from one another. The standard error bars are generally comparable across the VESs. Back to Figure 26.

Figure 27. Equation. Braking distance. d subscript BD equals V squared divided by the following: the sum of f and uppercase G, end of sum, that sum multiplied by lowercase g, multiplied by 2. Back to Figure 27.

Figure 28. Equation. Distance for brake reaction time and braking distance. d equals the following sum: 2.5 multiplied by V, that product plus the quotient of V squared divided by the product of 2 multiplied by g multiplied by f. Back to Figure 28.

Figure 29. Equation. AASHTO calculation of coefficient of friction for wet pavement. f equals a divided by g, which equals 11.2 feet per second squared divided by 32.2 feet per second squared, which equals 0.35. Back to Figure 29.

Figure 30. Bar graph. Comparison of the results obtained for UV–A headlamps with previous research. The graph is titled “Detection Distance Static Pedestrian.” The Y-axis is the mean detection distance in feet. The X-axis includes the 12 VESs evaluated in the current study and two VESs evaluated in a previous study. The additional VESs are labeled “US (HLB) May 97” and “UV–A May 97.” Standard error bars are also provided for each graph bar. Detection distances for the VESs evaluated in the current study range from approximately 725 feet for HID to 950 feet for three UV–A + HLB. The detection distance for the US HLB May 97 was approximately 360 feet. The detection distance for the UV–A May 97 was approximately 495 feet. The standard error bars for the two VESs from the 1997 study are smaller than the standard error bars for the VESs from the current study. Back to Figure 30.

Figure 31. Bar graph. Participants’ visual acuity divided by age group. The graph shows the participants’ acuity by age group. The Y-axis shows the number of participants from 0 to 7. The X-axis is broken down into the following acuity scores: 20/13, 20/15, 20/20, 20/25, 20/30, and 20/40. Each age group, young, middle, and older, is represented by a bar. Young participants’ visual acuity ranged from 20/13 to 20/25 with two or three participants in each category. Three participants in the middle age group had acuity of 20/13, one had acuity of 20/15, and the remaining six participants had 20/20 acuity. Six participants in the older age group had 20/20 acuity. One had 20/15 acuity and one had 20/30 acuity. The remaining two had 20/40 acuity. Back to Figure 31.

Figure 32. Bar graph. Participants’ contrast sensitivity at 1.5 cpd (cycles per degree) divided by age group. The Y-axis is labeled “Number of Participants,” and the scale starts at 0 and ends at 7. The X-axis is labeled “Percentage of Contrast at 1.5 cpd.” The X-axis is split in half with percentage of contrast values for the left eye on one side and the percentage of contrast values for the right eye on the other. The percentage of contrast values listed on the X-axis range from 0.59 (Good) to 5 (Poor) for each eye. There are three styles of bars, each one representing the participants in an age group (young, middle, or older). Participants in the younger and middle age groups were all able to see 2.86 percent of contrast or less. While the majority of participants in the older age group also were able to see 2.86 percent of contrast or less, a few were in the “poor” range and only able to see 5 percent contrast. No one in the older age group was able to see percentage of contrast less than 1.43. Back to Figure 32.

Figure 33. Bar graph. Participants’ contrast sensitivity at 3.0 cpd divided by age group. The Y-axis is labeled “Number of Participants” and the scale starts at 0 and ends at 7. The X-axis is labeled “Percentage of Contrast at 3.0 cpd.” The X-axis is split in half with percentage of contrast values for the left eye on one side and the percentage of contrast values for the right eye on the other. The percentage of contrast values listed on the X-axis range from 0.45 (Good) to 4.17 (Poor) for each eye. There are three styles of bars, each one representing the participants in an age group (young, middle, or older). The majority of participants fell into the 0.59 and 1.13 percent of contrast range. A few older participants fell into the “poor” range with contrast sensitivity scores of 4.17. Back to Figure 33.

Figure 34. Bar graph. Participants’ contrast sensitivity at 6.0 cpd divided by age group. The Y-axis is labeled “Number of Participants” and the scale starts at 0 and ends at 7. The X-axis is labeled “Percentage of Contrast at 6.0 cpd.” The X-axis is split in half with percentage of contrast values for the left eye on one side and the percentage of contrast values for the right eye on the other. The percentage of contrast values listed on the X-axis range from 0.38 (Good) to 4.76 (Poor) for each eye. There are three styles of bars, each one representing the participants in an age group (young, middle, or older). The majority of those in the younger age group could see either 0.54 percent of contrast or 0.8 percent of contrast. There were two scores of 4.76 (Poor) in the younger age group, one recorded for the left eye and one for the right eye. The range for the middle age group was 0.54 to 2.22. The older age group showed a trend toward the poorer end of the scale with 70 percent of the scores for the left eye falling at 2.22 percent of contrast or higher and 70 percent of the scores for the right eye falling at 1.43 percent of contrast or higher. Back to Figure 34.

Figure 35. Bar graph. Participants’ contrast sensitivity at 12.0 cpd divided by age group. The Y-axis is labeled “Number of Participants,” and the scale starts at 0 and ends at 7. The X-axis is labeled “Percentage of Contrast at 12.0 cpd.” The X-axis is split in half with percentage of contrast values for the left eye on one side and the percentage of contrast values for the right eye on the other. The percentage of contrast values listed on the X-axis range from 0.59 (Good) to 12.5 (Poor) for each eye. There are three styles of bars, each one representing the participants in an age group (young, middle, or older). The younger age group is represented across the entire range of scores from 0.59 to 12.5 percent of contrast. Seventy percent of the younger age group were able to see 1.14 percent of contrast or less. Ninety percent of the middle age group was able to see 1.82 percent of contrast or less. Sixty percent of the older age group could only see 3.13 percent of contrast or higher. Back to Figure 35.

Figure 36. Bar graph. Participants’ contrast sensitivity at 18.0 cpd divided by age group. The Y-axis is labeled “Number of Participants,” and the scale starts at 0 and ends at 7. The X-axis is labeled “Percentage of Contrast at 18.0 cpd.” The X-axis is split in half with percentage of contrast values for the left eye on one side and the percentage of contrast values for the right eye on the other. The percentage of contrast values listed on the X-axis range from 1.11 (Good) to 25 (Poor) for each eye. There are three styles of bars, each one representing the participants in an age group (young, middle, or older). Eighty percent of the younger age group could see 3.85 percent of contrast or less. Sixty percent of the middle age group could see 3.85 percent of contrast or less with the left eye, and 50 percent could see 3.85 percent of contrast or less with the right eye. Twenty percent of the older age group could see 3.85 percent of contrast or less. Thirty percent of the older age group could only see 14.29 percent of contrast or higher. Back to Figure 36.

Figure 37. Photo. Aerial view of the Smart Road. The photograph shows a paved road with a large turnaround at one end extending down into a valley at the other end. Back to Figure 37.

Appendix C: Contrast Sensitivity Test Diagram. The diagram shows the form the experimenters used to document the results for each participant’s contrast sensitivity exam. The diagram shows a graph with contrast sensitivity from 3 to 300 on the left Y-axis, contrast threshold from .3 to .003 on the right Y-axis, and spatial frequency (cycles per degree) from .5 to 6 on the X-axis. There is a column of numbered circles above each cycle per degree, indicating participant response. There are two diagrams, one for recording the results of the right eye and one for the results of the left eye. Back to Diagram.

Appendix E. Training Slide 1.

Enhanced Night Visibility

Schedule and Training

Back to Slide 1.

Appendix E. Training Slide 2.
  • Schedule
  • Training
    • Driver’s License Verification
    • Informed Consent
    • Forms and Questionnaires
    • Vision Tests
    • Laboratory Training
    • In-vehicle Familiarization
  • Night 1 and 2
    • On Road Study

Back to Slide 2.

Appendix E. Training Slide 3.

  • What is enhanced night visibility?
  • Why is your help important?
  • Vehicles:
    • Car
    • Pick-up
    • SUV
  • Scenario:
    • Smart Road test facility
    • Nighttime
    • Weather: Clear, Rain, Snow, or Fog

Back to Slide 3.

Appendix E. Training Slide 4.

  • Lab Training
  • This training will help orient you to:
    • the Thermal Imaging System
    • the definition of terms we will use
    • the procedures
    • the objects
    • what we will ask from you

Back to Slide 4.

Appendix E. Training Slide 5.

The Smart Road

For this research effort, you will be driving on the Smart Road test facility.

The Smart Road will be closed off to all traffic other than research vehicles. As a result, there will be at most two vehicles moving on the road, including the one you are driving.

Back to Slide 5.

Appendix E. Training Slide 6. The slide shows an aerial photo of a portion of the Smart Road.
Back to Slide 6.

Appendix E. Training Slide 7. The slide includes four separate photographs (one of a black SUV, one of a white SUV, one of a sedan, and one of a truck). All the photographs show the left side view of the vehicle and are taken from the back. The VESs are not visible in any of the photographs. The slide also includes the following text:
  • Experimental Vehicles
  • Vision Enhancement Systems
    • The Night Vision System
    • Prototype Headlamps

Back to Slide 7.

Appendix E. Training Slide 8.

  • Detection and Recognition
  • Your primary task is to drive safely
    • Night 1; 15 mph in gravel lot, 25 mph on paved road
    • Night 2; 25 mph on Smart Road
  • Your job will be to detect and recognize different objects on the Smart Road
  • You will be required to press a button when you both detect and recognize objects

Back to Slide 8.

Appendix E. Training Slide 9.

  • Detection of Objects
  • Detection is when you can just tell that something is on the road in front of you.
    • Detection is important while driving in that it prepares you to possibly make an evasive action
  • When you detect an object, push the button as soon as you know something is in the road.

Back to Slide 9.

Appendix E. Training Slide 10.

  • Recognition of Objects
  • Recognition is when you can say for sure what the object is.
    • This provides you with more information so you can adequately react to the object
  • When you can recognize the object, you must push the button and, at the same time, recognize the object to the experimenter by saying, “I see a _____.”
  • In case of an Unsuccessful recognition press the push button again as soon as you notice what the right object is and tell the experimenter.

Back to Slide 10.

Appendix E. Training Slide 11.

  • Types of Objects
  • Dynamic Objects
    • Pedestrians: You will be asked to recognize that the object is a pedestrian. The pedestrian will be either along the road or across the road.
    • Cyclists: People will be riding bicycles across the road.

Back to Slide 11.

Appendix E. Training Slide 12.

  • Types of Objects
  • Static Objects
    • Bicycle: A children’s bicycle will be laying on the right side of the road.
    • Tire Tread: A vehicle tire tread will be laying on the right side of the road.
    • Static pedestrian: A pedestrian will be standing still on the right side of the road.

Back to Slide 12.

Appendix E. Training Slide 13. The slide is titled “Dynamic Objects” and contains two separate photographs. One photograph is of a person wearing white clothing riding a bicycle. The other photograph is of a person wearing black clothing riding a bicycle. A single caption of “Bicyclists” is located under the photographs. Back to Slide 13.

Appendix E. Training Slide 14. The slide is titled “Dynamic Objects” and contains two separate photographs. One photograph is the side view of a person walking and wearing black clothing. The other photograph is of a person walking and wearing white clothing. A single caption of “Walking Pedestrians” is located under the photographs. Back to Slide 14.

Appendix E. Training Slide 15. The slide is titled “Static Objects” and contains two separate photographs. One photograph is of a child’s bicycle propped upright against a plain background. The bicycle has a yellow frame, pink tire rims, and white seat, tires, and pedals. The other photograph is of an intact circular tire tread with the sidewall removed. The tire tread is lying on its side against a plain background.
Back to Slide 15.

Appendix E. Training Slide 16.
  • Questionnaires
  • You will be asked to respond to a questionnaire after each VES
    • Headlamp configuration questionnaire: You will provide a numbered rating of each headlight on a scale from 1 to 7.
    • Show questionnaire

Back to Slide 16.

Appendix E. Training Slide 17.

What we need from you
Driving is the primary task, so use safe driving practices
Maintain the specified speed limit
Immediately push the button when you Detect and/or Recognize an object
Verbally identify all objects as you press the button for the Recognition portion
Respond to the questionnaires
Ask questions whenever you need to

Back to Slide 17.

Appendix E. Training Slide 18.

Questions?

Back to Slide 18.

Appendix J. Low beam alignment for hotspot. The diagram depicts a set of crosshairs with a circle centered in the lower right-hand corner. The caption above the diagram says “Hotspot Location: The circle represents the target hotspot location with respect to the target crosshairs. The center of the circle is the center of the hotspot.” Return to Diagram.

Appendix J. UV–A headlamp alignment for hotspot. The diagram depicts a set of crosshairs centered on a large circle. Two smaller circles are centered horizontally inside the large circle. Two smaller circles are also centered vertically inside the larger circle, but portions of them are overlapped by the horizontal circles. The caption above the diagram says “Hotspot Location: The large outer circle represents the overall target area. The center of the large circle is the target hotspot location.” Return to Diagram.

 

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