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Possibilities of Using a Wireless Telemetry System of a Recreational Vehicle (Off-Road)

Abstract

The development of electronic systems has significantly contributed to the rapid increase in the number of controllers working in vehicles, and thus the amount of data transferred between them. The large amount of information sent prevents the driver from directly mastering or understanding them, hence it was necessary to limit the displayed parameters on the instrument cluster to the most important ones, so that the driver can focus on driving. However, in motor sports and in various types of road tests or research, where the driver is supported by an additional team of engineers, information sent between vehicle controllers can prove extremely valuable. Most often, the whole staff of people responsible for conducted traction tests does not occupy the vehicle, so as not to disturb the conditions. Their analysis usually takes place in a designated service spot, in which case the parameters from the on-board data transmission network are usually transmitted by radio from the vehicle to the archiving system. Therefore, research into the development of wireless data transmission systems from vehicle controllers is also carried out at the Opole University of Technology. This article describes the possibilities of using a system built at the Opole University of Technology for wireless conduction of diagnostics and analysis of current operating parameters of a recreational All-Terrain Vehicle (ATV). In addition, in the designed system, it is also possible to connect external sensors to analyse parameters normally not registered during the course on normal vehicle operation.

Open access
Theoretical Investigation of Stresses Induced at Blade Mounting Locations in Steam Turbine Rotor System

Abstract

One of the most common incipient losses of integrity in mechanical structures is the development and propagation of cracks. Especially in rotating members like steam turbine rotors etc. cracks, because of their potential, cause catastrophic failures and are a grave threat to an uninterrupted operation and performance. A crack may propagate from some small imperfections on the surface of the body or inside of the material and it is most likely to appear in correspondence to high stress concentration. Crack propagation path is generally determined by the direction of maximum stress or by the minimum material strength. Hence determination of stresses induced has been the focus of attention for many researchers. In the present work, development of a mathematical model to determine the stresses induced in a rotating disc of varying thickness is studied. This model is applied to a steam turbine rotor disc to determine the induced stresses and radial deflection. The mathematical modeling results are validated with the results obtained using Ansys package. The results of the present study will be useful in diagnosing the location and magnitude of maximum stress induced in the turbine rotor disc and stress intensity factor due to the presence of crack.

Open access
Overhead Travelling Crane Construction Deflection Measurements with Telematic Approach

Abstract

Transport has always been a fundamental impulse for the development of civilization. Issues related to the regularity of operation of technical systems, in the last decade have become important issues being considered from both the point of view, as well as economics. Today the major threat in the operational reliability constitutes intensification of the machine and equipment use leading to excessive degradation. In automated manufacturing processes where the material handling operations are realized by the cranes, the safety as both devices and operating people constitute important factor. The main purpose of the article was focused on the set of issues including the material handling devices (MHD) reliability shaping problem especially presents work in progress towards development the MHD condition assessment system with using telematic approach. In the article author, special care was enclosed to MHD devices with strength human factor interaction and relatively large construction, so the overhead travelling crane was chose. The object of the statement constitutes an attempt of collecting the knowledge concerning a possibility of use modern measurement systems to monitoring crane bridge deflection. All tests and considerations were conducted on the double girder overhead travelling crane with hosting capability 1000 kg and bridge span 8000 mm.

Open access
An overview of Millionschikov's quasi-normality hypothesis applied to turbulence

Abstract

In this paper, we examine the zero-fourth cumulant approximation that was applied to fluctuating velocity components of homogeneous and isotropic turbulence by M.D. Millionschikov. Since the publication of the remarkable paper of Millionschikov, many authors have applied this hypothesis to solve the closure problem of turbulence. We discuss here various studies by the other authors on the developments of this hypothesis and their applications to the incompressible velocity temperature, hydrodynamic and magnetohydrodynamic fluctuating pressure fields and the general magnetohydrodynamic turbulence field. Lastly, we discuss broadly the computational difficulties that arise in turbulence problems and their possible refinements. We include also some enlightments of the process of future work that could be undertaken in this field of research

Open access
Technical Condition Assessment of the System of Gas Distribution Pipelines

Abstract

The objective of technical condition assessment of the system of gas distribution pipelines is to obtain reliable information concerning the technical condition of the particular sites of the distribution system for successful planning of their maintenance and repair works, as well as for taking decisions on the extension of the operation time, reconstruction or elimination. The developed methodology provides for the development of the indices describing the sites of the system of gas distribution pipelines - the base factor (Fij), the share of the score set for each factor (Вij) in the group of the factor shares (βi), the shares of the group (ai), based upon which, by means of applying the linear algorithm, the group calculation score (Bi) and the integral score (F) are set and according to these scores the technical condition of the particular site is assessed and the conditions for its further operation are defined.

Open access
The Power Impact of Electric Power Assist in Hybrid Vehicle

Abstract

The current interest in the development of hybrid vehicles is a response to serious effects of road transport on the environment over recent years. In addition, vehicles equipped with this type of drive combine the advantages of a conventional diesel engine and electric motor. This results in higher system efficiency while reducing emissivity.

This work seeks to demonstrate the effect of electric power on the total power of a hybrid vehicle. The research on the chassis dynamometer (MAHA LPS 3000) of the hybrid sports car, Honda CRZ, has been performed in three modes of operation: normal, economical and sport. The obtained results are presented in the form of graphs of external engine characteristics, where the influence of electric power on the system is visible.

The tested vehicle is equipped with sixth version of Honda’s Integrated Motor Assist (IMA) technology, which is the crucial system, assisting the combustion engine in order to provide higher performance and better fuel economy.

Open access
Systemic Approach and Model of the Polish Tactical Air Force

Abstract

The main purpose of this article is to present the structure of a tactical air force, on the example of the Polish Tactical Air Force, in a form of a technical system. This kind of technical system presents the technical point of view and organizationally bonds currently existing systems, objects (facilities) and components that are included into the Polish Tactical Air Force. The authors consider the Polish Tactical Air Force as the main analyses domain of this article. The model of presented system is mainly focused on operators’ organization and operation system of military aircraft, which are considered as technical objects (facilities) in a tactical air force. At the beginning of this article, the Polish Tactical Air Force is placed in more complex systemic structures. Then, the authors use the systems methodology, systems engineering, technical object-oriented (facility-oriented) approach and the matrix of the Model of Generalized Technical System to describe the Tactical Air Force System and present it via the model of such a system. The following model is based on a tree-shaped scheme divided into five levels of decomposition. The Model of Tactical Air Force System (as the “final product” of authors’ considerations over the selected analyses domain) has a considerable contribution to systems’ development in the Polish Armed Forces. The above-mentioned systems’ development could lead to greater progress in the Polish military as well as in systemic ideas. The implementation of the systems methodology in the design process of a new system, performed in a tactical air force, is an example of technical object systems engineering.

Open access
Geometrical Structure for Endoprosthesis Surface Lubrication and Wear Prognosis

Abstract

It can be stated that over the last ten years in the European Union, the number of bone fractures caused by osteoarthritis has increased twofold. More than 100,000 hip or knee joints in total were implanted in Germany during one year. Within ten years, 5% of them have failed by aseptic loosening. The non-invasive determination of friction forces and control of their values during lubrication of cartilage cells on the superficial layer of human joint surfaces before implantation has a significant but not sufficient impact on the observation of the early abrasive wear of the cartilage joint and development of osteoporosis. From this fact was drawn the inspiration for the performed investigations related to the endoprosthesis surface parameters because knowledge of the roughness of prosthesis surfaces and friction forces and their control methods permits provision of a necessary standard deviation of the gap height and finally information about the implantation possibility. This article has been prepared based on the objective of European Project UE Grant IRSES,612593, 2013-2016 to represent the methodology and goal of the idea described in and make a wider discussion possible on this subject for further developments during the realization. To the research methods and materials used in this article realization belong: Rank Taylor Hobson-Talyscan 150 Apparatus implemented by Talymap Expert and Microsoft Excel Computer Program connected with the Mathcad 15 Professional Program and a new semi-analytical methods of probabilistic and statistic prognosis applied for theory of hydrodynamic lubrication of the curvilinear orthogonal surface and coordinates extended to the friction and wear problems of the endoprosthesis surfaces during the exploitation.

Open access
Material Recovery as an Opportunity of Immediate Introduction of Eco-Friendly Transport System (Vehicles)

Abstract

The article presents an analysis of the need to introduce pro-ecological solutions at the fuel sector of industry, resulting from dynamic economic development, and environment protection requirements. The forecasts on the number of vehicles in the world and the subsequent growth of interest in alternative fuels are presented. The advantages of using these fuels as compared to petroleum fuels and electricity are described. The presented analysis emphasizes the context of EU legislation on environmental requirements. At the same time, it was pointed out the need to obtain the required technical and energy characteristics of alternative fuels, the competitive costs of their production, and important environmental aspects. Taking into account these premises and the principle of circular economy closed circuit, alternative fuels from organic waste, in particular from enormous amounts of organic non-biodegradable wastes (packaging, multi-material fabric, rubber, tires) were proposed. It has been shown that thermal decomposition by thermolysis, described briefly in the article, can be a method suitable for a wide economic application within the alternative fuel production system. Based on literature data and own experience, it has been found that the quality of fuels (oil, gas) obtained from the thermal decomposition of organic and mixed waste is not different from the requirements for the best quality raw materials used in the production of petrol and may even exceed the properties of petroleum. Introduction of the system of regional production and distribution of alternative fuels from waste could be remarkable driver of small towns and rural areas revitalization and development, while supporting build up and improvement of local communities.

Open access
From the History of Conferences on the Machine and Mechanism Science

] Wojnarowski J. (2011): The Significance and Role of IFToMM Poland in the Creative Development of Mechanism and Machine Science , pp.367-382, [in M. Ceccarelli (ed.). Technology Developments: the Role of Mechanism and Machine Science and IFToMM, Mechanism and Machine Science 1, Springer Science]. Wojnarowski J. 2011 The Significance and Role of IFToMM Poland in the Creative Development of Mechanism and Machine Science 367 382 Ceccarelli M. Technology Developments: the Role of Mechanism and Machine Science and IFToMM, Mechanism and Machine Science 1

Open access