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• Enhanced Night Visibility Series, Volume VI: Phase II—Study 4: Visual Performance During Nighttime Driving in Fog

Enhanced Night Visibility Series, Volume VI: Phase II—Study 4: Visual Performance During Nighttime Driving in Fog

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APPENDIX K—AIMING PROTOCOL

PROTOCOL SUMMARY

Vehicle/Headlamp Combinations Acronym List:

• It is very important to make sure that you have enough time to align all of the headlights prior to the team meeting, and especially prior to the road preparations. Minimum alignment time is 1 hour when no headlamps need to be switched between vehicles, but you should plan on 1 ¼ - 1 ½ hours as a general rule. Alignment times will be greater on days when headlamps must be moved.
• It is important to remember to use the ZERO function on the photometer prior to aligning each light. This is particularly important when recording the photometer values on the Headlamp Alignment form.

Setting up the Non-UV–A headlamps

Applies to the following Vehicle/Headlamp combinations:
SUV #1 HLB (1&2), SUV #2 HLB (1&2)
SUV #3 HID (1 & 2)

• Use the laser to make sure the target board is centered to the vehicle. Each vehicle has a different line on the target board. The lines are labeled directly on the target board. The lines from left to right are: SUV #1 Laser Line, SUV #2 Laser Line, and SUV #3. Locate the appropriate markings on the target board for each VES.
• Turn on the appropriate headlamps, making sure no auxiliary lights (parking lights, fog lights, daytime running lights) are on.
• Cover up or unplug one headlamp so that you are only taking readings for one light at a time.

Note that for non-UV lights, the HLBs in particular, the hotspots actually span a large horizontal swath, 2-4 inches wide. It is relatively easy to determine the hotspot vertically, but determining the hotspot horizontally requires more effort and patience given that the horizontal hotspot can be 2-4 inches wide.

Setting up the UV–A headlamps

• Use the laser to make sure the target board is centered to the vehicle. Each vehicle has a different line on the target board. The lines are labeled directly on the target board. The lines from left to right are: SUV #1 Laser Line, SUV #2 Laser Line, SUV #1 UV, and SUV #2 UV. If you are aligning the UV headlamps on SUV number 2, you should use the SUV #2 -UV laser line. All other vehicles require the use of the standard alignment point.
• Turn on the appropriate headlamps, making sure no auxiliary lights (parking lights, fog lights, daytime running lights) are on.
• Locate the appropriate markings on the target board for that headlamp.
• Cover up the headlamps so that you are only taking readings for one light at a time.

Note that it is sufficient to line up the sensor on the crosshairs such that at least the edge of the sensor touches the center of the crosshairs. This means that there is a circular space around the center of the crosshairs, with a radius the size of the sensor in all directions (about 2 inches in diameter), in which the hotspot may be found. This is a larger margin of alignment error than allowed for the non-UV lights and is due to the nature of the mounting of the lights.

Reference values for the Various Headlamps:

Note: You look at this table as you look at the target board for calibration; it’s backwards when looking directly at the vehicles.

Headlamp Alignment Form

Date:______________________________

Inits:____________________________