The aiming of the headlamps in this project was a critical component of the ENV vehicle setup. The repeatability of the aim for a headlamp was vital to the reduction of uncertainty caused by the lighting conditions. The general methods for the aiming of all of the headlamps in the project are provided in appendix A. Specific methods are shown in each of the ENV experimental reports.
There are two subtypes of the visually optically aligned (VOA) systems, visually optically aligned left (VOL) and visually optically aligned right (VOR). VOL headlamps are aimed so that the sharp cutoff of the light pattern on the left of the lamp is aimed to a vertical aiming plane. VOR headlamps are aimed using the right portion of the beam as the reference. VOL systems have a vertical aiming plane 0.6 below the vertical reference point on the alignment board. VOR systems have a vertical aiming plane at the same height as the reference point. Figure 7 and figure 8 show the aiming planes used.
The HLB, HOH, and HHB headlamps used in this study were mechanically aimed systems. With this type of headlamp, the reference for the position of the headlamp is based on three aiming pads located on the lens of the luminaire. These pads and measurements shown on the headlamp are used with a mechanical aiming device. Optical aimers that analyze the beam pattern and set the maximum luminous intensity of the headlamp beam to a specified location also can be used to aim this type of headlamp.
For this investigation, neither an optical aimer nor a mechanical aimer was available. It was decided that an illuminance meter with a remote sensor would be used to find the maximum luminous intensity of the beam, and then the headlamps would be aimed so that this maximum point was located at a selected point relative to the reference point. As with the VOA headlamps, the reference point was chosen as specified by SAE J599, 1997.(10) The point selected for the maximum luminous intensity of the beam was at 2.5 cm (1 inch) to the right and 2.5 cm (1 inch) below this reference point at the 10.7-m (35-ft) alignment distance. The sensor element of an illuminance meter was positioned at this point while the headlamp was slowly adjusted to determine the orientation at which the maximum luminous intensity of the beam (hotspot) was directed toward the selected point (figure 9).
During the measurements made as part of this characterization, it was discovered that this is not the typical location for the maximum luminous intensity of the beam. Although not an exact specification, SAE 1383, 1996, shows that the maximum allowable luminous intensity of the beam should be located approximately 1.5 down and 2 to the right of the reference point (table 3A of SAE 1383 1996).(11) At 10.7 m (35 ft), these dimensions translate to 27.9 cm (11 inches) down and 37.2 cm (14.7 inches) to the right, the location used by optical aimers.(9) This means that the aiming of the HLB, HOH, and HHB all have a deviation of approximately 1.36 above and 1.77 to the left of the typical point of maximum luminous intensity. This deviation was consistent across all of the studies performed with these headlamps.
After compiling a massive list of testing options again this year, we chatted with experts to define the most important features of a good headlamp. They told us that a good headlamp is mostly just a flashlight that you strap to your head, with long-lasting battery life and a reliable, bright light that can be controlled with easy-to-use buttons. We used the following criteria to determine which headlamps to test:
Once we narrowed down our list, we called in our old favorites and ordered some newer options, for a total of 17 headlamps. We ran these headlamps through a series of king-of-the-hill tests to see whether the new beat out the old. In some cases, they did. In most cases, though, our previous picks reigned supreme. We ran the following tests with each headlamp:
The light and battery specs on headlamp boxes are highly misleading, so we wanted to test the lights ourselves to see how they behaved during their marketed run times. We turned on all 17 headlamps to their highest setting and checked them every hour for 12 hours. We took notes on which headlamps burned out, which ones dimmed, which ones automatically turned themselves off (only the kids options did), and which ones looked just as steady after 12 hours as they did in the first hour.
Sure, headlamps are a practical purchase, but they can also be a fun gadget for kids to play with at the campsite or during backyard adventures. The kids we know use them mostly while pretending to be red-eyed monsters or rainbow unicorns, and who are we to judge? The Black Diamond Wiz kids headlamp is lightweight and easy to adjust. And it offers a feature that prompted our testers to place it above all of its competitors: rainbow lights.
The load condition and pitching motion of the vehicle change the illumination range of the headlamps. This may dazzle other road users. This is why headlamp levelling systems (HLS) are legally prescribed. On this page, find out how standard market systems work, and how you can check them with simple means. Here, you can also learn what to do in the event of malfunction, and what you should note when adjusting headlamps with an automatic HLS.
The block diagram shows the design of a dynamic headlamp levelling system. The control unit calculates the nominal data on the basis of the sensor data, taking the driving conditions into account. In contrast to semi-static headlamp leveling systems, the actuator motors are then triggered within fractions of a second. To make these quick response times possible, stepper motors are mainly used as actuators on the headlamps.
HELLA offers optimal customer-specific system solutions. Headlamp levelling actuators for integration into headlamps, as well as externally mounted headlamp levelling actuators with or without basic manual settings are available in 12 V and 24 V versions. A fully automated manufacturing process with high quality standards guarantees an output of more than 10 million actuators a year. Due to a consistent increase in international production sites, we can also supply customers with actuators from Korea, India, and China.
As a sensor-integrated control unit on the rear axle, this solution for the automated headlamp levelli