scholarly journals WEAR OF SPHERICAL JOINTS OF THE VEHICLES STEERING SYSTEMS. VIBRATIONS AND THEIR ROLE IN DIAGNOSIS

2020 ◽  
Vol 10 (3) ◽  
pp. 16-20
Author(s):  
Mihai GINGARASU ◽  
Elena MEREUTA ◽  
Valentin AMORTILA ◽  
Costel HUMELNICU ◽  
Monica NOVETSCHI

Motor vehicles have an important role in our lives, the need for mobility making them present in daily activities. In a more open world, people want to be able to move, not only more and more, but also increasingly better. In the current context of the intensification, both nationally and internationally, of road transport, the need for safe traffic traffic is a primary objective for the operation of motor vehicles. Combining vehicle technology enhancements with an improved driver training, with a better road infrastructure design and an enforcement of existing traffic regulations is an important goal for society in order to increase road safety. During the operation of the vehicles, their component systems interact both with each other and with the external environment and these interactions are generating variations of some technical state parameters. As a result, there is a continuous change in the technical state of the vehicles, which causes variations in the dynamic, economical, air pollution, ergonomic, comfort and safety performances. This pape analyzes the vibrations of the steering system components, under different operating conditions and according to the technical state of the spherical joints. The measurements were made using a 4-channel digital recorder DA20-RION, with data processing software DA-20 VIEWER and a triaxial accelerometer Brüel & Kjær, type 4321. The paper highlights the possibility of monitorin the technical state of the spherical joints, analyzing the vibrations produced under different driving conditions of the vehicles and, at the same time, it opens the perspective of the implementation of intelligent devices to ensure the early detection of these failures.

Author(s):  
Zbigniew STANIK ◽  
Andrzej KUBIK ◽  
Damian HADRYŚ ◽  
Csaba CSISZÁR

This article presents two methods of testing bearing hubs, which may supplement the existing subjective and unreliable methods of diagnostics of rolling bearings used in wheel bearing hubs of motor vehicles and other means of road transport. One of the most important elements responsible for the safety of a vehicle is the bearing hub. Regular monitoring of the technical condition of bearings should become an obligation at vehicle inspection stations when carrying out a technical inspection of a vehicle, authorising it to travel on public roads. This article presents the results of vehicle tests with signs of damage to rolling bearings, using two test stands: one on which the dynamic balancer acted as a device for accelerating the wheel, and the other, which was designed as a test dedicated to automotive rolling bearings, where a dynamic weighbridge was used as the wheel drive, made it impossible to test the wheel at lower rotational speeds. The newly designed and manufactured bearing testing device eliminates the disadvantages of the previous stand, and additionally, enables the measurement of a fully loaded bearing hub, which enables the simulation of real operating conditions on the bearing hub.


Author(s):  
S.V. Ilyanov ◽  
◽  
N.A. Kuzmin ◽  
G.V. Borisov ◽  
◽  
...  

At the moment, there is a large number of dissertations and scientific works covering the issues of traction-speed and fuel-economic characteristics of vehicles, the results of which are presented in the form of: regression models, approximating dependencies, mathematical models based on multivariate analysis, including a number of additional coefficients. In this connection, the use of the results of these works in practice is limited, since it requires high qualifications of the МTЕ personnel and the use of special software and hardware. At the same time, at the department “Automobile transport” NSTU named after R. E. Alekseev developed a probabilistic-analytical method for predicting fuel consumption by road trains, considering the high-speed mode of movement, which shows a high convergence of results with actual average speeds only for uniform movement of buses with a constant average speed, which is not applicable to the assessment of fuel consumption of city buses. Based on the hypothesis put forward on the applicability of the Weibull-Gnedenko distribution for calculating the average speeds of city buses and the normal distribution for calculating accelerations during movement, the tasks of this study are formulated, expressed in the development of mathematical models reflecting the dependences of speeds and accelerations during bus movement in urban operating conditions, for planning their fuel consumption. To solve the set tasks, the following experimental studies were carried out: determination of the average coefficient of total road resistance; the actual distribution of speeds and accelerations when driving city buses; determination of the average actual value of fuel consumption when the bus is moving and when idle at stopping points. Based on the results of processing experimental studies, the possibility of using the Weibull-Gnedenko law to describe the actual speeds in urban conditions and the normal law to describe accelerations when driving city buses was confirmed, which allows planning fuel consumption using the analytical apparatus of the theory of probability and mathematical statistics and using the developed methodology in practice of motor transport enterprises. Based on experimental studies and theoretical studies in this area, an analytical method for planning fuel consumption for city buses, considering the speed of their movement, has been developed, which allows planning fuel consumption without additional experiments. Carrying out such studies for other types of motor vehicles and assessing unaccounted for indicators of road, transport and natural-climatic operating conditions will create a generalized analytical method for planning fuel consumption by vehicles in various operating conditions.


2020 ◽  
Vol 13 (2) ◽  
pp. 126-140
Author(s):  
Jing Gan ◽  
Xiaobin Fan ◽  
Zeng Song ◽  
Mingyue Zhang ◽  
Bin Zhao

Background: The power performance of an electric vehicle is the basic parameter. Traditional test equipment, such as the expensive chassis dynamometer, not only increases the cost of testing but also makes it impossible to measure all the performance parameters of an electric vehicle. Objective: A set of convenient, efficient and sensitive power measurement system for electric vehicles is developed to obtain the real-time power changes of hub-motor vehicles under various operating conditions, and the dynamic performance parameters of hub-motor vehicles are obtained through the system. Methods: Firstly, a set of on-board power test system is developed by using virtual instrument (Lab- VIEW). This test system can obtain the power changes of hub-motor vehicles under various operating conditions in real-time and save data in real-time. Then, the driving resistance of hub-motor vehicles is analyzed, and the power performance of hub-motor vehicles is studied in depth. The power testing system is proposed to test the input power of both ends of the driving motor, and the chassis dynamometer is combined to test so that the output efficiency of the driving motor can be easily obtained without disassembly. Finally, this method is used to carry out the road test and obtain the vehicle dynamic performance parameters. Results: The real-time current, voltage and power, maximum power, acceleration time and maximum speed of the vehicle can be obtained accurately by using the power test system in the real road experiment. Conclusion: The maximum power required by the two motors reaches about 9KW, and it takes about 20 seconds to reach the maximum speed. The total power required to maintain the maximum speed is about 7.8kw, and the maximum speed is 62km/h. In this article, various patents have been discussed.


2011 ◽  
Vol 121-126 ◽  
pp. 4635-4639
Author(s):  
Hao Hao ◽  
Xing Gen Wu ◽  
Hong Yu Li

The author maintains that, with the quick development of domestic auto industry, the auto maintenance industry is progressing with high speed accordingly. The auto maintenance enterprise are inclined to focus on sales and forward supply chain operation, however, lacking of efficient resource and systematic management into reverse logistics operation, as lead to a few potential risks. In order to avoid and control the risks, the auto maintenance companies need to closely cooperate with channel supply chain partners, meanwhile build up the mode of reverse logistics operation with timing efficiency orientation. This mode consists of eight sub-system modules: organization structure, network planning and layout, reverse logistics operation procedure, time window evaluation mechanism, automatic replenishment system, reverse forecasting system, Kan-ban message system as well as disposal & reuse system. Furthermore, the article makes analysis of the internal operations and external relevance of these eight sub-systems. In recent years, with the overall opening up of road transport market and the rapid growth in domestic economy, the total number of China’s motor vehicles is entering a high-speed growth channel, and “the car goes to the country” policy further promotes the auto industry. Under the situation of quick development, the auto maintenance industry is developing by 10% to 15% each year as a young profession. According to the statistics, there are over 380,000 auto maintenance enterprises in our country at the moment, and various types of auto safety testing stations are built around one after another. The intense competition among auto maintenance manufacturing enterprises does not only focus on product quality, but also on the after-market reverse logistics. According to the statics of Gartner, 70 percent of resale is related with sales service, and 60 percent of resale is related with after market. However, except for few leading business enterprises which have realized the direct influence and value contribution of after-service reverse logistics to profit increase and customer loyalty and take action to pioneer the profit territory in the after-sale reverse logistics, the ‘price war’ is still the main competition method which the majority of enterprises adopt in the market.


Author(s):  
Roman I. Dremliuga ◽  
Andrey A. Yakovenko

Развитие технологий автономного автотранспорта является одним из приоритетов в технологическом развитии Российской Федерации. Несмотря на прогресс в данной сфере, вряд ли можно говорить о значимых успехах России во внедрении использования автономного транспорта на дорогах общего пользования. В основе данного исследования лежит утверждение, что правовой режим является либо катализатором, либо замедляющим фактором развития сферы автономного автотранспорта. Цель исследования – провести анализ правовых норм в сфере тестирования и эксплуатации автономного автотранспорта в Европе. Авторы полагают, что исследуемые европейские страны имеют достаточно проработанную нормативную базу в данной сфере, поэтому их опыт может быть полезен в разработке и модификации российской правовой базы для регулирования отношений в сфере использования автономного автотранспорта. Задачи исследования: а) определить нормативную базу, связанную с регулированием отношений по тестированию и эксплуатации автономных транспортных средств; б) выявить позицию лидирующих европейских стран, связанную с вопросами необходимости регулирования таких отношений; в) оценить перспективы возможности заимствования положительной практики регулирования рассматриваемой сферы общественных отношений в правовую действительность Российской Федерации. Методологической основой исследования послужили диалектический метод познания, общенаучные методы абстрагирования, анализа и синтеза, а также специальные юридические методы (сравнительно-правовой, логико-юридический и др.). В статье делается вывод, что в процессе создания нормативно правовой базы власти стремятся детально урегулировать исследуемую область общественных отношений. Рассмотренные страны имеют практически схожую модель регулирования, с жёсткими нормативными рамками. Авторы полагают, что некоторые ограничения являются неблагоприятными для развития сектора цифровой экономики. Тем не менее, опыт европейских стран может быть использован в России в первую очередь для определения проблемных точек регулирования и организации контроля за тестированием и использованием автономного автотранспорта. Ключевые слова: Европейский Союз, регулирование тестирования автономного автотранспорта, беспилотный автотранспорт, цифровая экономика, искусственный интеллект, кибербезопасность, распознавание образов, киберправо, беспилотные транспортные средства, цифровая трансформации, умные вещи, умный город, сравнительное правоведение, сравнительный анализ, новый технологический уклад, право Нидерландов, право Германии, право Великобритании, право информационных технологий, право ИТ. The development of unmanned (autonomous) vehicle technologies is one of the strategic priorities of the Russian Federation. Despite a great deal of attention to this area, one can hardly speak of any significant success of Russia in introducing the use of autonomous vehicles on public roads. This study is based on the assumption that the legal regime is a catalyst or a deterrent to the development of autonomous motor transport or a deterrent to the development of the autonomous motor transport sector. The aim of the study is to analyze the legal norms in the field of testing and operation of autonomous road transport in Europe. The authors believe that the studied European countries have a sufficiently developed regulatory system in this area; therefore, their experience can be useful in developing and modifying the Russian legal framework to regulate the use of autonomous road transport. The objectives of the study are as follows: a) to define the regulatory framework related to the regulation of relations in the testing and operation of autonomous vehicles; b) to identify the position of the leading European countries related to the issues of the need for regulation and its limits; c) to assess the prospects for the possibility of taking the positive practice of regulation of the considered sphere of social relations into the legal reality of the Russian Federation. The dialectical method of cognition, general scientific methods of abstraction, analysis and synthesis, as well as special legal methods (comparative legal, logical-legal, etc.) served as the methodological basis for the research. The article concludes that in the process of creating a legal system the authorities seek to regulate in detail the area of public relations under study. The countries under study have almost similar model of regulation with rigid normative frameworks. The authors believe that some restrictions are unfavorable for the development of digital economy sectors. Nevertheless, the experience of European countries can be used in Russia first of all to identify problem points of regulation and organization of control over testing and use of autonomous motor vehicles.


2020 ◽  
Vol 182 (3) ◽  
pp. 54-58
Author(s):  
Andrzej Ziółkowski ◽  
Paweł Fuć ◽  
Piotr Lijewski ◽  
Łukasz Rymaniak ◽  
Paweł Daszkiewicz ◽  
...  

Road transport holds for the largest share in the freight transport sector in Europe. This work is carried out by heavy vehicles of various types. It is assumed that, in principle, transport should take place on the main road connections, such as motorways or national roads. Their share in the polish road infrastructure is not dominant. Rural and communal roads roads are the most prevalent. This fact formed the basis of the exhaust emissions and fuel consumption tests of heavy vehicles in real operating conditions. A set of vehicles (truck tractor with a semi-trailer) meeting the Euro V emission norm, transporting a load of 24,800 kg, was selected for the tests. The research was carried out on an non-urban route, the test route length was 22 km. A mobile Semtech DS instrument was used, which was used to measure the exhaust emissions. Based on the obtained results, the emission characteristics were determined in relation to the operating parameters of the vehicles drive system. Road emission, specific emission and fuel consumption values were also calculated.


2018 ◽  
Vol 77 (3) ◽  
pp. 141-148
Author(s):  
M. Yu. Khvostik ◽  
I. V. Khromov ◽  
O. A. Bykova ◽  
G. A. Beresten’

The monitoring of railway rails damage on the railway network of the JSC “Russian Railways” as well as operational and polygon tests are conducted with the purpose of assessing the impact of operating conditions on the intensity of rails damage, obtaining initial data for forecasting rails failures. The increased intensity of rails wear on sites with a complex plan and profile leads to the fact that with a continuous change from the track, rails which have an underutilized service life of more than 20 % are retrieved. Polygon tests on the Test Loop of the JSC “VNIIZhT” near the Scherbinka station can provide the repeatability and reliability of the results, comparative tests are carried out under identical conditions and their duration is several times less than when tested at experimental sites under operational conditions. The results of the polygon tests of new differentially heat-strengthened rails did not reveal any advantages in the wear resistance of special purposed rails (laid in the recommended radius of the curve for its application) when comparing the rails of domestic manufacturers. Metal shelling out on the rolling surface of rails is the main reason for the removal of rails from test batches. The origin and development of defects of this kind is due to both violations of the technology of manufacturing rails, and because of violations of the current maintenance of the track. The metal stock in the area of the rail head of R65 type due to the increase in its dimensions positively affects the extension of the lifetime of the rails, reducing the cost of the life cycle and the rail itself, and the design of the track as a whole. When carrying out a separate study in order to obtain results characterizing the stability of high-quality rails to contact fatigue damage, it is advisable to optimize the conditions of the polygon tests, bringing them closer to operational ones. When forming the test results, it is necessary to expand the list of criteria for assessing the wear resistance of rails, supplementing it with the size of the wear area at the time of a certain operating time of the tonnage, with the introduction of this criterion into the appropriate methods for the polygon (operational) tests.


Author(s):  
Justin Gossard ◽  
Steven A. Waters ◽  
Shane Finneran

Construction blasting was proposed as a technique to create a trench for a new pipeline within the right-of-way (ROW) of an existing vintage pipeline where soil conditions consisted primarily of rock. Several field experiments were conducted to assess the potential loading conditions that the vintage pipeline could experience due to various blasting configurations as part of the nearby construction process. Two test pipe segments were constructed from segments removed from the vintage pipeline for use in these experiments. Each test segment contained two vintage bell-bell chill ring girth welds (GW) and were pressurized to operating conditions of the vintage pipeline for the duration of all blasting. Groups of eight resistive strain gages were bonded around the exterior surface of three distinct locations on each test segment. The three locations include one pipe body location and each of the two welds on each segment. Four separate experiments were conducted with each experiment focusing on a unique combination of trench backfill material, compaction level and separation distance from the test pipe segments and the explosive charges. The primary objective throughout these four experiments was to monitor and record the behavior of buried test pipe sections due to nearby blasting activities. Long range 3-dimentional (3D) laser scanning equipment was used to track movement of each test segment from test to test. High-speed video equipment was also employed to capture each blast. The high-speed video provided additional details on the blast energy transfer, verification of individual charge initiation as well as pipeline test segment movement where each pipeline segment was exposed. Peak particle velocity measurements were taken during each test blast. Strain data collected during each test was used to assess potential damage to the vintage pipeline test segments as a result of blasting. The combined information collected from the in-field testing showed that elevated strains and stresses may be observed during blasting activities near pipelines.


2018 ◽  
Author(s):  
Shah Alam ◽  
Rahul Yelamanchili

Concentrated photovoltaic thermal system is a reliable solar energy system that utilizes sunlight of higher concentration on a photovoltaic cell to generate energy that is superior to conventional solar systems due to fewer space requirements and high electrical and thermal efficiencies. The primary objective of this thesis was to test two operating conditions of the concentrated photovoltaic thermal system and find the condition that delivers maximum output when compared to the other. The first condition tested in this research included variable velocity of water flowing in the cooling channel while a constant amount of heat flux was applied on the photovoltaic cells. The second tested condition included constant velocity of water flowing in the cooling channel while varying the amount of heat flux applied on the photovoltaic cells. Through mathematical modeling, that includes, thermal modeling and energy analysis was carried out for the concentrated photovoltaic thermal system along with simulations of the system that were performed using a three-dimensional finite element analysis software called Ansys Workbench (Fluent). The results from this research provide a useful path in improving the efficiency of the concentrated photovoltaic thermal system.


Forests ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 385
Author(s):  
Anil Raj Kizha ◽  
Han-Sup Han ◽  
Nathaniel Anderson ◽  
Anil Koirala ◽  
Libin T. Louis

The balance of production activities at the landing is pivotal to the success of any forest harvesting operation and has a direct impact on the cost and efficiency of the enterprise. The primary objective of this study was to understand the operational characteristics of the loader in a hot operation (handling both sawlog and biomass components concurrently) and cold operation (handling biomass and sawlogs separately) for harvesting sawlogs and biomass. Systematic work sampling techniques were employed to obtain “snapshots” of the loader activities for a cable logging operation, including the interaction of the loader with other operational phases and delay time for both hot and cold configurations. The results show that for hot loading at the landing, the yarder was the most utilized machine (85%), and was the bottleneck of the operation, followed by the loader (70%). In the hot loading configuration, 39% of operational delay during truck loading was caused by the loader and was predominantly due to movement of the loader within or between the landings. This was followed by the yarder (19%, due to rigging activities) and the chaser (15%, to maintain the crews’ safety). In the cold loading configuration, delays due to the unavailability of roll-off bins constituted up to 77% of the operational delay. This suggests that the number of bins and trucks hauling biomass has a crucial role in the overall efficiency of the biomass harvesting system, and should be well balanced with loading capacity. Additionally, the choice of hot or cold biomass loading operations is highly dependent on the site and operating conditions.


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