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The aim of this paper is to establish the design process of a system that expedites concreting, the Topbelt. Two connected conveyors that provide five degrees of freedom are known as the Topbelt System. These two conveyors are suspended via a rope connection to a Lattice boom of a crane, Manitowoc 4100 S. The required concrete that should be handled by Topbelt is provided by a feeder. The suspended Topbelt system is capable of transporting concrete to levels of both higher and lower than the ground horizontal level. This concreting mechanism sweeps a circle of about 85-meter diameter, centering at the crane swing on the swing plane level. The Topbelt is suspended using two winches, one of them is for keeping conveyor1 in its proper position and the other is applied to keep conveyor2 by a rope guide mechanism, which allows the rotational movement of conveyor2 with respect to conveyor1. Expediting concrete process in dam construction is the main advantages of the Topbelt system.

The aim of this paper is represented design and manufacturing process of change of functioning of a scrapped shovel (Ruston Bucyrus R32) to a lattice boom crane of 300-ton capacity. Capabilities of the structure, changed components, additional required components (e.g. boom, mast, winch…) and modifying critical dimensions of this shovel were surveyed. In this paper, some of the 300-ton capacity lattice boom cranes of various companies were considered and critical dimensions that play an important role in system stability were surveyed. After that, their major dimensions were compared with those of a common shovel. In order to design the structure and components of this shovel-based crane, static, dynamic and wind loads were calculated. Finally, the critical dimensions of the shovel related to chassis and crawler were modified. This crane was used for lifting heavy machineries in the right zone of the main body of Seymareh dam site (Ilam-Iran) and played a vital role on that project.

Automotive industry compartment is undertaking a massive technology revolution. ADAS systems and infotainment promise to change the way that customers mean travel and transportation radically, through several use cases. The key enabling technologies for this trend are Ethernet and its newly standardized physical layer, IEEE 802.3bw 100BASE-T1 (a.k.a. BroadR-Reach). From an architectural point of view, the evolution of the applications that rely on Automotive Ethernet resembles in many ways the evolution that the IT has had in the last decades. In the IT world, increased throughput and computational power to the end-user enabled technologies like multimedia streaming; scalability and availability requirements, together with the increased complexity of IT infrastructure, led to the “Anything as a Service” paradigm and Software Defined Networks.

The objective of this study is to identify the most popular agricultural tractor models in Russia by their engine ratings and countries of origin. This review presents an analysis of changes in the composition of engine-ratings and sales volume of agricultural tractors in the Russian market between 2008 and 2014. Including knock-down kits, the countries of origin are Russia, the CIS-countries and non-CIS Countries. The variety of manufacturers, highlight the leading international companies which have supplied up to 200 units is discussed. The papers shows that CIS-manufactured tractors represent the greatest number in the market - up to 57 per cent, tractors from non-CIS countries occupy up to 12 per cent of the market, and the number of Russian models is quite limited - 3.0 per cent in 2012 and 3.4 per cent in 2014.

Typically, earthmoving machines do not have wheel suspensions. This lack of components often causes uncomfortable driving, and in some cases reduces machine productivity and safety. Several solutions to this problem have been proposed in the last decades, and particularly successful is the passive solution based on the introduction of accumulators in the hydraulic circuit connecting the machine boom. The extra capacitance effect created by the accumulator causes a magnification of the boom oscillations, in such a way that these oscillations counter-react the machine oscillation caused by the driving on uneven ground. This principle of counter-reacting machine oscillations through the boom motion can be achieved also with electro-hydraulic solutions, properly actuating the flow supply to the boom actuators on the basis of a feedback sensors and a proper control strategy.

China has become the world’s largest vehicle market in terms of sales volume. Automobiles sales keep growing in recent years despite the declining economic growth rate. Due to the increasing attention given to the environmental impact, more stringent emission regulations are being drafted to control traditional internal combustion engine emissions. In order to reduce vehicle emissions, environmentally-friendly new-energy vehicles, such as electric vehicles and plug-in hybrid vehicles, are being promoted by government policies. The Chinese government plans to boost sales of new-energy cars to account for about five percent of China’s total vehicle sales. It is well known that more electric and electronic components will be integrated into a vehicle platform during vehicle electrification.

Body structure design needs to meet multi-attributes requirements such as global bend stiffness/modal, torsion stiffness/modal, Noise and velocity transfer functions (NTF/VTF), and others. Computer-aided engineering (CAE) is a significant way to enhance the accuracy of design results. However, it also brings computation burden for optimization. In order to improve the performance and reduce the weight of automobile body structure, this paper presents a novel process of body CAE multi-attributes optimization. Four significant phases are described: 1) Sensitivity analysis for each body CAE performance, 2) MDO process, 3) Non-sensitive gauges reducing, and 4) Slightly optimization. Considering the mixed variables in the MDO process including continuous geometry shapes and discrete gauges, the developed continuous relaxation method was employed to deal with such situation.

Aerodynamic drag contributes to 50-60% of fuel consumption in trucks on highways. The limits of conventional wind tunnel testing have forced researchers to study about the drag and ways of reducing it computationally. Due to the stricter norms and eco-friendly approaches, truck manufacturers have begun to invest more for developing truck aerodynamics. This paper evaluates a European vehicle on European conditions. Drag reduction are mostly made by geometric changes. Pressure drag, a major drag for trucks as they run at lower speeds is produced by the shape of the object. Making streamlined bodies as trucks are tougher since it can affect its purpose. Therefore, addition of some components can suffice the needs. The changes in geometry have been implied and analysis for these geometrical changes are done to analyze the better geometry which can provide drag reduction features. The geometrical changes considered are providing side skirts, boattails and roof deflector angle.

With increasing use of boat-tails on Canadian roads, a concern had been raised regarding the possibility for ice and snow to accumulate and shed from the cavity of a boat-tail affixed to a dry-van trailer, posing a hazard for other road users. This paper describes a preliminary evaluation of the potential for ice and snow accumulation in the cavity of a boat-tail-equipped heavy-duty vehicle. A transient CFD approach was used and combined with a quasi-static particle-tracking simulation to evaluate, firstly, the tendency of various representative ice or snow particles to be entrained in the vehicle wake, and secondly, the potential of such particles to accumulate on the aft end of a dry-van trailer with and without various boat-tail configurations. Results of the particle tracking analyses showed that the greatest numbers of particles impinge on the base of the trailer for the no-boat-tail case, concentrated on the upper surface of the back face of the trailer.

The noise generated by the flow of air past a transport truck is a key design factor for the manufacturers of these vehicles as the sound levels in the cabin are a significant component of driver comfort. This paper describes a collaboration between Volvo GTT and the National Research Council Canada to measure the in-cabin aeroacoustics of a full-scale cab-over tractor in the NRC 9 m Wind Tunnel. Acoustic instrumentation was installed inside the tractor to record cabin noise levels and externally to acquire tunnel background noise data. Using a microphone mounted on the driver’s-side tunnel wall as a reference to remove variations in background noise levels between data points, differences in cabin noise levels were able to be detected when comparing the tractor with different configurations. The good repeatability of the data allowed for differences of as little as 0.5 dB to be measured.

Side window clarity and its effect on side mirror visibility plays a major role in driver comfort. Driving in inclement weather conditions such as rain can be stressful, and having optimal visibility under these conditions is ideal. However, extreme conditions can overwhelm exterior water management devices, resulting in rivulets of water flowing over the a-pillar and onto the vehicle’s side glass. Once on the side glass, these rivulets and the pooling of water they feed, can significantly impair the driver’s ability to see the side mirror and to see outwardly when in situations such as changing lanes. Designing exterior water management features of a vehicle is a challenging exercise, as traditionally, physical testing methods first require a full-scale vehicle for evaluations to be possible. Additionally, common water management devices such as grooves and channels often have undesirable aesthetic, drag, and wind noise implications.

The trucking industry is being encouraged by environmental and cost factors to improve fuel efficiency. One factor that affects fuel efficiency is the aerodynamic design of the vehicles; that is, the vehicles with lower aerodynamic drag will get better mileage, reducing carbon emissions and reducing costs through lower fuel usage. A significant tool towards developing vehicles with lower drag is the wind tunnel. The automobile industry has made great improvements in fuel efficiency by using wind tunnels to determine the best designs to achieve lower drag. Those wind tunnels are not optimum for testing the larger, longer heavy trucks since the wind tunnels are smaller than needed. The estimated costs for a heavy truck wind tunnel based on automotive wind tunnel technology are quite high. A potential nozzle concept to reduce wind tunnel cost and several other new possible approaches to lower wind tunnel costs are presented.

To investigate the feasibility of various test procedures to determine aerodynamic performance for the Phase 2 Greenhouse Gas (GHG) Regulations for Heavy-Duty Vehicles in the United States, the US Environmental Protection Agency commissioned, through Southwest Research Institute, constant-speed torque tests of several heavy-duty tractors matched to a conventional 53-foot dry-van trailer. Torque was measured at the transmission output shaft and, for most tests, also on each of the drive wheels. Air speed was measured onboard the vehicle, and wind conditions were measured using a weather station placed along the road side. Tests were performed on a rural road in Texas. Measuring wind-averaged drag from on-road tests has historically been a challenge. By collecting data in various wind conditions at multiple speeds over multiple days, a regression-based method was developed to estimate wind-averaged drag with a low precision error for multiple tractor-trailer combinations.

The dynamic loading on the skin of a refrigeration unit mounted in the gap between tractor and trailer is studied while another trailer passes by on a freeway using transient computational fluid dynamics. Dynamic Meshing methodology available in Ansys Fluent was used to understand the transient pressure and flow regimes in and around the tractor trailer gap in general and refrigeration unit in particular, at various vehicle speeds. The influences of the lateral distance between the crossing trailers and vehicle speed on the pressure distribution on the refrigeration unit have been studied.

While initial Connected Vehicle research in the United States was focusing almost exclusively on passenger vehicles, a program was envisioned that would enhance highway safety, mobility, and operational efficiencies through the application of the technology to commercial vehicles. This program was realized in 2009 by funding from the I-95 Corridor Coalition, led by the New York State Department of Transportation, and called the Commercial Vehicle Infrastructure Integration (CVII) program. The CVII program focuses on developing, testing and deploying Connected Vehicle technology for heavy vehicles. Since its inception, the CVII program has developed numerous Vehicle-to-Vehicle and Vehicle-to-Infrastructure applications for trucks that leverage communication with roadside infrastructure and other light and heavy duty vehicles to meet the objectives of the program.

Since the turn of the millennium, automated vehicle technology has matured at an exponential rate, evolving from research largely funded and motivated by military and agricultural needs to a near-production market focused on everyday driving on public roads. Research and development has been conducted by a variety of entities ranging from universities to automotive manufacturers to technology firms demonstrating capabilities in both highway and urban environments. While this technology continues to show promise, corner cases, or situations outside the average driving environment, have emerged highlighting scenarios that impede the realization of full automation anywhere, anytime. This paper will review several of these corner cases and research deficiencies that need to be addressed for automated driving systems to be broadly deployed and trusted.

Reliability engineering methods are used to assess risk and eliminate hazards by estimation, elimination, and management of risks of failures. The ISO 26262 functional safety standard gives detailed guidance on reliability engineering methods like Failure Mode and Effect Analysis (FMEA) [7], Fault Tree Analysis (FTA) [8] [2], and etc. While, there are many methods available for reliability engineering; no single method is foolproof for securing safety by eliminating hazards completely. Out of these methods, FMEA is widely being used as an integral part of the product development life cycle [10]. In this method, failure modes of individual components are analyzed considering one failure at a time. FMEA is an efficient method for analyzing failures in simple systems. For complex systems, FMEA becomes impractical. It is also difficult to consider variables in FMEA.

Body in white (BIW) forms a major structure in any automobile. It is responsible for safety and structural rigidity of the vehicle. Also, this frame supports the power plant, auxiliary equipments and all body parts of the vehicle. When it comes to judging the performance of the vehicle, BIW is analyzed not only for its strength and shape but also the weight. Light weight BIW structures have grown rapidly in order to fulfill the requirements of the best vehicle performance in dynamic conditions. Since then lot of efforts have been put into computer-aided engineering (CAE), materials research, advanced manufacturing processes and joining methods. Each of them play a critical role in BIW functionality. Constructional designing, development of light materials with improved strength and special manufacturing practices for BIW are few research areas with scope of improvement. This paper attempts to review various factors studied for BIW weight reduction.

In this paper, researchers at the National Renewable Energy Laboratory present the results of simulation studies to evaluate potential fuel savings as a result of improvements to vehicle rolling resistance, coefficient of drag, and vehicle weight as well as hybridization for four powertrains for medium-duty parcel delivery vehicles. The vehicles will be modeled and simulated over 1,290 real-world driving trips to determine the fuel savings potential based on improvements to each technology and to identify best use cases for each platform. The results of impacts of new technologies on fuel saving will be presented, and the most favorable driving routes on which to adopt them will be explored.

Recent regulations on greenhouse gas (GHG) emission standards for heavy-duty vehicles have prompted government agencies to standardize procedures assessing the aerodynamic performance of Class 8 tractor-trailers. The coastdown test procedure is the primary reference method employed to assess vehicle drag currently, while other valid alternatives include constant speed testing, computational fluid dynamics (CFD) simulations, and wind tunnel testing. The main purpose of this paper is to compare CFD simulations with a corresponding 1/8th scale wind tunnel test. Additionally, this paper will highlight the impacts of wind tunnel testing on the total drag coefficient performance as compared to full scale open road analysis with and without real world, upstream turbulence wind conditions. All scale model testing and CFD simulations were performed on a class 8 tractor with a standard 53-foot dry-box trailer. The wind tunnel testing was performed in the Auto Research Center (ARC) wind tunnel.