# Optimizing Non-Glare Zone Width of Adaptive Driving Beam (ADB) Using Fuzzy Logic Control
## 1 Introduction  
Automotive forward lighting is significant for driving safety, especially for night driving. An ideal forward-lighting system for vehicles should be able to provide adequate illumination of the road and surrounding area for the driver while not creating uncomfortable glares for other road users. Conventional vehicle forward-lighting systems have two fixed beam patterns: a high beam and a low beam. The high beam provides good long-range visibility to the driver, but it will create a strong glare for both oncoming and preceding vehicles. The low beam, however, minimizes the glare by sacrificing road illumination. Adaptive driving beam (ADB) is an advanced vehicle forward-lighting system that automatically adapts its beam patterns to create a non-glare zone that includes both oncoming and preceding vehicles. Studies show that, in most driving scenarios, a vehicle equipped with ADB could provide the driver with road illumination equivalent to a high beam [1], while the glare it creates for other road users is similar to a vehicle with its low beam turned on [2, 3]. Due to the limitations of the system, however, indirect glare in the rearview mirror was experienced in some sharp corners; an example of such a sharp corner is shown in Figure 1, in which the minimum curvature of the pointed S-curve is approximately 25 m. This limitation is caused by the nighttime vehicle recognition technology used in the ADB system. Due to poor lighting conditions at night, instead of recognizing the entire geometry of the vehicle, the camera in the ADB system recognizes vehicles only by the light projected from them [4, 5]. Most of the nighttime vehicle detectionand recognition algorisms are based on the light's color [6; 7; 8; 9] and symmetricity [10; 11], which differentiate the taillight of the vehicle from ambient lights. The boundary box is created based on such lamp recognition results to represent the vehicle. As a result, in the same direction sharp-cornering driving scenario, the rearview mirror will be moved away from the boundary box of the rear lamp during the maneuver. Indirect glare is created if the non-glare zone is not wide enough. This problem can be fundamentally solved if the geometry of the entire vehicle is recognized by the system instead of just its light. The deformable part model (DPM) has been used for object recognition in good lighting conditions. [PERSON] et al. [12] improved the performance for vehicle detection at night using DPM with a lateral filter that allows the system to recognize the vehicle geometry in low-lighting conditions. [PERSON] et al. [13] presented a vehicle recognition algorithm with low-light enhancement with artificial intelligence and machine learning. [PERSON] et al. [14] proposed an approach for images captured at nighttime that uses near-infrared camera images with deep learning. Those algorithms show the potential of such detection being used for future ADB systems. Another solution is to predict the maneuver of the stimulus vehicle using sensor fusion. [PERSON] et al. [15] improved the ADB system using sensor fusion and predictive algorithms in twisting roads and passing-car scenarios. In the field of adaptive forward-lighting systems (AFS), [PERSON] and [PERSON] [16] studied eye-tracking technology, and [PERSON] [17] presented a navigation-based virtual sensor for the AFS. Those predictive technologies could also be applied in mitigating the glare issue for ADB. [PERSON] et al. [18] designed laser diode scanning to improve the resolution of ADB; combined with those additional inputs, the non-glare zone can be projected more precisely to avoid glare while maximizing illumination. Each such improvements of ADB require additional hardware for the system or a more advanced algorithm. With the currently existing system, this problem can also be solved by widening the non-glare zone, though at the cost of road illumination. The question is how to find the best non-glare zone width to balance the issue of glare and road illumination.