Varroc Lighting Systems (United States)

<div class="section abstract"><div class="htmlview paragraph">These days, the use of virtual simulations through the Computational Fluid Dynamics (CFD) methodology is increasing exponentially during the development phase of an automotive headlamp. Thereupon, the automotive industries are becoming competent enough to build an ingenious and creative design with optimal performance within the coherent time. A considerable amount of heat is generated inside the headlamp when it is switched on for a longer time. Hence it becomes vital to reduce the risks if any during the development phase by providing an adequate thermal management strategy within the headlamp. The present study conducted an experimental analysis on an automotive headlamp to decide its thermal characteristics and behavior. Numerical analysis was also performed to determine the airflow and temperature distributions within a headlamp. This study also focuses on finding the main hotspot regions over the headlamp through virtual simulations. The methodology shows a consensus with the experimental and numerical analysis results.</div></div>

<div class="section abstract"><div class="htmlview paragraph">The functional safety of electric vehicles has attracted a great deal of attention among automobile industries globally. A tricky yet necessary dual gamut of operational ease along with operational safety is something that cannot be ignored while using electric vehicles. Safety paired with vehicle reliability will go a long way in the market. Therefore, abnormal vehicle behavior due to factors such as unintended acceleration should not be kept in hindsight. Unintended acceleration is a phenomenon where the vehicle accelerates involuntarily without the knowledge of the driver which leads to accidents and fatal injuries. Thus, prior detection of unintended acceleration becomes mandatory for driver’s safety.</div><div class="htmlview paragraph">Unintended acceleration is a result of various uncontrolled conditions like road driving conditions and system malfunction. This paper aims to estimate the load torque of a vehicle by utilizing the vehicle drive train model thereby ensuring the timely detection of unwanted acceleration in a vehicle. Two hazard mitigation methods have also been proposed based on the severity and cause of unintended acceleration.</div></div>

The lattice integral transforms have been introduced to generalize lower and upper fuzzy transforms for lattice-valued functions that are used to approximate original functions from below and above. They are defined in complete analogy with classical integral transforms, particularly, the product of a lattice-valued function and a fuzzy relation called the integral kernel is integrated by a Sugeno-like fuzzy integral. In the article, we first investigate the conditions under which lattice integral transforms preserve (reverse) constant functions, which appears to be a fundamental presumption for a successful approximation of lattice-valued functions. Further, we show how the lattice integral transforms can be applied in image processing, more specifically, in non-linear filtering, compression/decompression, and opening/closing of images. We demonstrate that the filters based on integral transforms generalize the popular median filter as well as minimum and maximum filters, and also opening and closing defined using fuzzy morphological erosion and dilation. We illustrate the proposed methods in various selected images.

<div class="section abstract"><div class="htmlview paragraph">In a traction drive, feedback of the torque developed on the motor shaft is necessary for proper implementation of torque-control. However, measuring torque using a torque-sensor for feedback is not practically feasible due to high levels of vibration in vehicles and high sensor cost. Therefore, an accurate run-time estimation of the instantaneous value of the developed electromagnetic torque is essential for robust control. Online estimation of torque is a challenging task due to non-linear variation in motor parameters such as self and mutual inductances. Traction motors are designed to achieve high levels of power and torque density. This causes wide variations in magnetic saturation levels in the rotor and the stator core. This results in significant variation in inductance values with change in loading condition and during field-weakening operation of these motors. This paper presents the design and analysis of a torque observer that works on the principles of a Model Reference Adaptive System (MRAS). A dq-frame model of permanent magnet synchronous motor (PMSM) is used as the reference model to estimate d and q-axis currents. Thereafter, those estimates are compared with measured values of <i>i<sub>d</sub></i> and <i>i<sub>q</sub></i> to generate error which then is used by a suitably designed adaption mechanism to alter the parameters of the reference model to better represent the actual plant. The reference model thus keeps adapting itself to the parameter variations in the motor and hence, can estimate the developed torque accurately. A simple adaption mechanism is proposed in this paper that does not require high computational resource for implementation. The performance of this approach has been verified by simulation studies performed on a torque controlled PMSM drive. To analyse the effects of inductance variations and other uncertainties a high-fidelity mathematical model of a PMSM drive is created using data generated from electromagnetic finite element analysis (FEA). This model accurately captures the variations in self and mutual inductances of all phases with changing load, field-weakening, and rotor position. Results of an extensive simulation study indicate that the proposed adaptive mechanism is quite effective in estimation and control of developed torque.</div></div>

<div class="section abstract"><div class="htmlview paragraph">Since 2012, adaptive driving beam (ADB) was homologated first in the ECE world (ECE 123). The idea behind is a camera based lighting system, which enables the driver to achieve at night nearly high beam visibility without glaring oncoming or proceeding vehicles and road users. Once the presence of other vehicles is detected the headlamps change the light pattern and block the light where the oncoming or proceeding vehicles are located.</div><div class="htmlview paragraph">Light sources are typically High Intensity Discharge (HID) bulbs, but today also first LED applications are visible.</div><div class="htmlview paragraph">For SAE, the definition of the parameters and the requested regulation changes to allow such systems are in progress.</div><div class="htmlview paragraph">The paper reports about an extensive study executed in Germany at TU Darmstadt to investigate not only the improvement in visibility for the driver with such systems, but also evaluate the disability and discomfort glare for other road users.</div><div class="htmlview paragraph">The results are demonstrating clearly, that the existing ADB systems do not cause additional glare for the road users and also do not lead to an increased subjective discomfort glare rating. The positive effect for the driver in enhancing the visibility at night is significant and improves safety at night time driving.</div></div>