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The increasing availability of data, which becomes a continually increasing trend in multiple fields of application, has given machine learning approaches a renewed interest in recent years. Accordingly, manufacturing processes and sheet metal forming follow such directions, having in mind the efficiency and control of the many parameters involved, in processing and material characterization. In this article, two applications are considered to explore the capability of machine learning modeling through shallow artificial neural networks (ANN). One consists of developing an ANN to identify the constitutive model parameters of a material using the force–displacement curves obtained with a standard bending test. The second one concentrates on the springback problem in sheet metal press-brake air bending, with the objective of predicting the punch displacement required to attain a desired bending angle, including additional information of the springback angle. The required data for designing the ANN solutions are collected from numerical simulation using finite element methodology (FEM), which in turn was validated by experiments.

Press brakes are among the most important machines used in sheet metal processing. In these machines, different numbers of molds are used for sheet bending and these molds are placed in the system by an operator. However, this process is slow, error-prone, and dependent on human labor. In this study, a real-time system that automatically detects molds and manipulates a robotic arm was designed using YOLOv4 and image processing. YOLOv4, a deep learning (DL)-based object detection algorithm, was applied to detect the positions, types, and holes of molds. Classical image processing methods were implemented to find the center (X, Y) coordinates of the mold hole. This study shows that the press brake machines currently used in industry can be transformed into smart machines through DL, image processing, camera systems, and robotic arm features.

The issues of import substitution of the working tool of foreign press brakes were considered using reverse engineering. The main cause of failure is the deformation of the tool’s working edges, which cannot be restored, so the only solution is to replace it. The complexity of manufacturing the working tool lies in the absence of design documentation for punches and dies, which requires creating it independently through reverse engineering, including the technology of creating a product model through direct measurements. Laser 3D scanning was used to create digital models, based on which drawings of the punch and die were developed, as well as the technology for their manufacture. Experimental-industrial tests of the manufactured bending tool showed that its operational durability practically does not differ from imported counterparts.

Laser surface hardening is a promising surface technology to enhance the properties of surfaces. This technology was used on the 42CrMo press brake die. Its hardening behavior was investigated by using scanning electron microscopy and electron backscattering diffraction. The results indicated that the martensite in the hardening zone was significantly finer than that in the substrate. There were many low-angle grain boundaries in the martensite of the hardening zone, and the kernel average misorientation and grain orientation spread in the hardening zone grains were obviously greater, which further improved the hardness of the hardening zone, especially near the substrate. The microstructure and the properties of the blade maintained excellent uniformity with treatment by single-pass laser surface hardening with a spot size of 2 mm, scanning speed of 1800 mm/min, and power of 2200 W. The hardness of the hardening zone was 1.6 times higher than that of the base material, and the thickness of the hardening zone reached 1.05 mm.

In this study, modifying a constant speed–driven hydraulic press brake machine into a variable speed drive system is examined in terms of electricity saving, CO2 reduction, and economic perspectives. The goal of the modification is to obtain increased efficiency by adding minimum hardware and software tools. For realizing this goal, a hydraulic test rig operated in a manner to represent the cycle of a specified press brake machine is taken into consideration, which is equipped with a frequency controller on an induction motor and an electro-hydraulic load sensing. Then, the amount of electricity saving is determined experimentally under wide-range operating conditions. Besides, an economic analysis is performed based on 5 different scenarios to represent the conditions of the real industry throughout an operation year. As a result, the amount of electricity saving is observed to vary between 3 and 19% depending on the operating conditions. In addition, it is determined that there is 1.75 to 10.5 tons of CO2 reduction potential per year. The payback period of the modification investment is computed between 1.51 and 4.67 years, according to the considered scenarios. In the sensitivity analysis, the most important parameters affecting the economic criteria are discount rate, electricity unit price, and initial investment cost.

Brake wear emission is a significant contributor to vehicle-related particulate matter, especially in areas with high traffic density and braking frequency. Only recently, non-exhaust emissions from car brake wear have been regulated under Euro 7 regulation, which introduces emission limits for both brake and tires. It also introduces a standard brake particle assessment procedure which includes sampling procedure and measurement techniques defined in the Global Technical Regulation on brakes from light-duty vehicles up to 3.5 t. Over the years, various experimental setups have been tried leading to non-comparable results. The brake wear particle emissions, expressed as emission factors, are mostly estimated as particle mass or particle number and described using different units (e.g., mg/stop brake, mg/km brake; particle number/cm 3 ) making the comparison between studies very difficult. The aim of the present literature review is to present the state-of-the-art of different experimental methods tuned for assessing brake wear emissions, including electric vehicles. The experiments are carried in close, semi-closed, and open systems, and depending on the experimental design, different sampling methods are applied to reduce particle transport loss and guarantee the efficiency of the particle sampling. Driving condition (e.g., speed and applied pressure), formulation of brake materials, and friction temperature have been found to strongly affect the emission characteristics of brake particles, and this needs to be considered when designing study procedures. The findings reported in this review can be beneficial to policy makers and researchers.

Particulate Matter (PM) air pollution has been linked to major adverse health effects. Road transport still contributes significantly to ambient PM concentrations, but mainly due to the non-exhaust emissions from vehicles. For the first time worldwide, limits for non-exhaust emissions have been proposed by the European Union for the upcoming Euro 7 step. For these reasons, interest in brake emissions has increased in the past few years. Realistic emission factors are necessary to accurately calculate the contribution of brake emissions to air pollution but also to estimate the emissions reduction potential of new or existing technologies and improved brake formulations. This paper reviews emission factors from light-duty vehicles reported in the literature, with a focus on those that followed the recently introduced Global Technical Regulation (GTR 24) methodology on brakes in light-duty vehicles. Reduction efficiencies of non-asbestos organic (NAO) pads, brake dust filters, ceramic discs, coated discs, and regenerative braking are also discussed. Finally, the emission factors are compared with roadside measurements of brake emissions and emission inventories worldwide. The findings of this study can be used as an input in emission inventories to estimate the contribution of brakes to air pollution.

Brake torque is one of the key parameters of aircraft brake system design. When braking, hydraulic oil enters the brake actuator assembly, the piston on the brake actuator is extended under the action of liquid pressure, the rotor and static brake discs are pressed together, and the friction between the brake discs forms the brake torque. The design of brake torque is too small, which will increase the deceleration distance of the aircraft and can not meet the requirements of the aircraft design field. Excessive brake torque will make the aircraft pause and transition during braking, make passengers feel uncomfortable, and make the aircraft carry unnecessary weight. Generally, the combined torque between the tire and the runway during the RTO or landing stage is called the dynamic brake torque. The torque required to satisfy 25.735 (d)parking brake item in airworthiness CCAR-25-R4 is called the static brake torque. Brake system designers need to calculate the dynamic brake torque and static brake torque requirements, and design brake actuator assembly to meet these requirements.

Gray cast iron (GCI) is a popular automotive brake disc material by virtue of its high melting point as well as excellent heat storage and damping capability. GCI is also attractive because of its good castability and machinability, combined with its cost-effectiveness. Although several lightweight alloys have been explored as alternatives in an attempt to achieve weight reduction, their widespread use has been limited by low melting point and high inherent costs. Therefore, GCI is still the preferred material for brake discs due to its robust performance. However, poor corrosion resistance and excessive wear of brake disc material during service continue to be areas of concern, with the latter leading to brake emissions in the form of dust and particulate matter that have adverse effects on human health. With the exhaust emission norms becoming increasingly stringent, it is important to address the problem of brake disc wear without compromising the braking performance of the material. Surface treatment of GCI brake discs in the form of a suitable coating represents a promising solution to this problem. This paper reviews the different coating technologies and materials that have been traditionally used and examines the prospects of some emergent thermal spray technologies, along with the industrial implications of adopting them for brake disc applications.

For achieving the desired vehicle speed, the IC engine is very important, while for further vehicle speed maintaining and adaptation to road conditions, the braking system is important. With each brake’s activation, wear products are forming, which are very harmful to the environment, because they can contain heavy metals. The braking working parameters (initial speed and braking pressure) are beside the achieved temperature in contact par, the most responsible, for particle formation and their release into the air. The particles forming can be divided by size on coarse, fine, and ultrafine particles, and which were observed in the paper. However, the greatest accent was placed on coarse and fine particles. For the determination of the composition of wear products, most often, laboratory tests were used. Particle composition greatly depends on the composition of brake pads, which can consist of about 30 components, and where some of these components have very unfavourable effects on people’s health. So today, many researches are focused on finding such composition for brake pads, which will wear as less as possible, without disturbing the basic tribological properties. The conclusion of this paper shows that the applied materials for manufacturing the braking system are very important, as well as the construction, for the reduction of particle emission.