Razvan-Catalin Miclea

In mobile systems, fog, rain, snow, haze, and sun glare are natural phenomena that can be very dangerous for drivers. In addition to the visibility problem, the driver must face also the choice of speed while driving. The main effects of fog are a decrease in contrast and a fade of color. Rain and snow cause also high perturbation for the driver while glare caused by the sun or by other traffic participants can be very dangerous even for a short period. In the field of autonomous vehicles, visibility is of the utmost importance. To solve this problem, different researchers have approached and offered varied solutions and methods. It is useful to focus on what has been presented in the scientific literature over the past ten years relative to these concerns. This synthesis and technological evolution in the field of sensors, in the field of communications, in data processing, can be the basis of new possibilities for approaching the problems. This paper summarizes the methods and systems found and considered relevant, which estimate or even improve visibility in adverse weather conditions. Searching in the scientific literature, in the last few years, for the preoccupations of the researchers for avoiding the problems of the mobile systems caused by the environmental factors, we found that the fog phenomenon is the most dangerous. Our focus is on the fog phenomenon, and here, we present published research about methods based on image processing, optical power measurement, systems of sensors, etc.

Visibility is a critical factor for transportation, even if we refer to air, water, or ground transportation. The biggest trend in the automotive industry is autonomous driving, the number of autonomous vehicles will increase exponentially, prompting changes in the industry and user segment. Unfortunately, these vehicles still have some drawbacks and one, always in attention and topical, will be treated in this paper—visibility distance issue in bad weather conditions, particularly in fog. The way and the speed with which vehicles will determine objects, obstacles, pedestrians, or traffic signs, especially in bad visibility, will determine how the vehicle will behave. In this paper, a new experimental set up is featured, for analyzing the effect of the fog when the laser and LIDAR (Light Detection And Ranging) radiation are used in visibility distance estimation on public roads. While using our experimental set up, in the laboratory, the information offered by these measurement systems (laser and LIDAR) are evaluated and compared with results offered by human observers in the same fog conditions. The goal is to validate and unitarily apply the results regarding visibility distance, based on information arrives from different systems that are able to estimate this parameter (in foggy weather conditions). Finally, will be notifying the drivers in case of unexpected situations. It is a combination of stationary and of moving systems. The stationary system will be installed on highways or express roads in areas prone to fog, while the moving systems are, or can be, directly installed on the vehicles (autonomous but also non-autonomous).

The automotive industry is developing continuously, trying to improve, among others, the safety of drivers, passengers, and pedestrians. Using modern technology, the dangers caused by weather hazards like rain, snow, fog, or glare were identified and reduced. This paper presents an anti-glare solution using existing technologies that can be found already in a high-end car like the driver’s eyes tracking systems, light intensity sensors, or head-up displays. In addition to the existing elements, a sun tracking sensor is required to detect the point where the sun light has the maximum intensity on the windshield surface. Knowing the driver’s position and the point on the windshield where the sunlight has a high intensity, a dark spot can be created on the windshield in order to reduce the discomfort created by glare. Depending on the intensity of the light and taking into consideration the traffic safety laws, the spot’s transparency can vary between certain limits. Therefore, the dangers caused by glare will be diminished and the risks of not observing pedestrians, other traffic participants, traffic signs, or sudden curves will be considerably lower. Another advantage of using a digital sunshade based on smart glass or in-glass transparent displays, instead of a regular sunshade, is that the whole windshield can be protected against glare not just the top of it. The results were verified and highlighted using computer simulations done via a MATLAB environment.