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The purpose of this paper is to present the design process and subsequent numerical analysis calculations of a new roof-mounted bicycle carrier for vehicles. The bicycle carrier is mounted on the vehicles longitudinal bars. The designed construction is subjected to both static and dynamic load sets to check if it meets the requirements of ISO 11154 norm – which specifies the minimum safety requests for roof load carrier intended for mounting on the roof of passengers cars and light commercial vehicles with a maximum authorized total mass up to 3,5t. To fulfil the specifications associated to safety, standards and traffic laws test four different software packages were used: CATIA V5 and NACA airfoil generator for designing, Cambridge Engineering Selector for choosing the most suitable materials and Abaqus CAE for Finite Element Analysis.

The aim of this paper is to carry out the process of applying TRIZ in the mobile biogas station by using its tools and techniques. The design system was chosen as the field in which TRIZ has been approached. The TRIZ method was introduced and its unique capability to solve problems was presented. To adopt TRIZ methodology to achieve the objective the deep understanding of the system and the identification of the problem was needed. Therefore, this paper presents the mobile biogas station and compares it with the current needs of the market. The research stage was carried out by the systematic following the steps outlined by the Oxford Creativity handbook. Some TRIZ tools were used to overcome psychological inertia and pessimistic people influence encountered especially at the beginning of the work. Finally, the undertaken techniques enabled a feasible and novel mobile station to be designed. The concepts were developed and detailed computer-aided models were completed. They were also analyzed and evaluated by finite element method in terms of undergone structural stress.

In this study authors present a method which was used to investigate the causes of boom elements cracking on Brokk90 demolition machine. This type of machine is used by ARCAD demolition company from Wroclaw, Poland. Their specialty are demolition jobs, which require use of wide variety of equipment. In particular they offer demolition with use of small remotely controlled robots. In this case operators of the Brokk90 machine discovered crack growth which appeared on the sections of the arm system, to which a variety of tools can be mounted such as hydraulic breakers, hydraulic cutters, diamond chain saws etc. Crack growth occurred much earlier than time before overhaul designed by the manufacturer. The investigation of the of the arm system was carried out by the authors of this paper. In order to minimize the time during which the machine will not be operational, it has been decided to use noninvasive methods of measuring and recording the movement of the arm system during operation. Techniques used for this study consists of using Phantom high speed camera and Commtest vb7 vibrometer. Clips recorded via the high speed imagining system were processed using state of the art processing software which determined excitation acting on the arm system while in operation. Use of vibrometer allowed to investigate natural frequencies of the assembly, and later on validate built FEA model. Based on recorded data boundary conditions for the simulations were determined and used in the simulation. During the study a fully functional finite element analysis model of the arm system was developed. Study of the model allowed researchers to thoroughly investigate stresses occurring in the elements of the arm sections. Based on the similarity between places of stress concentration on the model and places of crack formation on the arm system, high level of correlation between real life machine and simulation model was established.

A demolition robot is a multi-functional, remote-controlled machine, which is designed to be operated in severe work conditions such as high temperature, dust, radiation or noise. The publication presents the approach to enhance both the robustness of the machine—through Finite Element optimization—and the ergonomics of machine operator by implementing Human-Machine Interface (HMI). The combination of performed experimental and numerical research provided the information about the unfavorable effort and frequency states of the machine in the various operation processes. The use of advanced numerical simulations in pair with experimental tests were applied to estimate the dangerous states of the structure of the machine, as the designing stage enables to elaborate the HMI warning control system of the machine operation.

All the machines that are used in various sectors of the machine industry are usually the work of the team which consists of many specialized people. Generally the final effect is evaluated which is the physically produced machine that people can see, touch and use. In fact, no one realizes how much effort and work is needed to make the team successfully complete the design of the machine and start the long-awaited final stage which is the manufacturing. Each machine before the start of manufacturing passes through the stages of design and construction. It should be noted that these steps are one of the most important in the whole process of the manufacture of machinery.

The article presents the opportunity to power internal combustion engine by treated and non-purified biogas. Internal combustion engines may be operated only within a certain range of parameters of fuel due to the design and method of operation. Furthermore, they are sensitive to changes in chemical composition of the fuel. The aim of the work described in the studies was to test the quality of biogas that can be obtained by methane fermentation of the test material. Considering the treatment of biogas as a consumable in vehicles, its physicochemical properties can be very diverse. It is reasonable therefore to analysis biogas composition of samples from various biogas plants, in the context of the possibility of its use in a motor vehicle with an internal combustion engine. The article presents an analysis of the chemical composition of untreated biogas collected from five representative biogas plants. Then it summarizes the data received with the requirements of the standards referred to European countries and set out the possibility of direct use of untreated and untreated biogas during the operation of vehicles with combustion engines.

This paper presents the methodology for assessing the process of designing and constructing vehicles and machines, which implements Design for Six Sigma tools. An important purpose of this paper is to determine how defects affect the quality of the structure, based on the criteria of its conformance. The paper also presents the requirements needed to implement the method and the benefits arising from the use of quality assessment tools. The presented method enables the quality assessment of the design and construction process, which also serves as quality assurance method due to the possibility to avoid potential defects.

The study presents selected problems concerning the testing of protective structures for the mining machines in the field of passive safety. Such machines equipped with protective structures must meet the requirements of the relevant regulations and standards. Requirements of conducting experimental tests of protective structures: FOPS, ROPS and RSPS are specified. The paper provides the principles of development of computational models for numerical simulations by means of finite element method. A detailed example of comparison of experimental and simulation results for a protective structure is presented.

The approach of designing a power transmission model (diagnoser) of the multi-bucket wheel excavator used in brown coal mining, presented in the study, helps prepare an effective method for identifying the states of developing fault. In order to develop such model/diagnoser it was necessary to measure the loads required for determination of the distribution function of the mining moment. Probabilistic methods were applied for establishing the state of initiating activities to protect against fault.

According to the strategy of Total Quality Management (TQM) [7] effective quality assurance of mechanical objects is maintained by means of permanent monitoring processes carried out in the cycle of product formation. The quality assessment of processes and the optimization of their crucial elements are the necessary condition for the improvement of efficiency and achievement of high level of customer satisfaction [15]. So far most of the techniques used for the process improvement are adopted to Lean Six Sigma methodology [1, 2, 11, 12, 17]. Achieving the quality on the level of 6 sigma is a primary goal of applying this methodology. Opinions exist that Lean Six Sigma should be implemented in the large number of areas of the life, and its effects (essential improvement in financial results through the reduction of poor quality costs) are hard to overrate. High effectiveness of every single process that is possible to achieve by applying the Lean Six Sigma strategy, became a source of inspiration for the study of Design For Six Sigma (DFSS) [4, 8, 12, 13], with purpose to improve object quality by implementing the innovation in product development.

In bolted flange joints of flexible constructional elements, bolts are subjected not only to tension and torsion but also to bending loads. Identification of straining of each bolt is only possible by means of numerical methods e.g. the finite element method. In the case of large objects, the calculation problem is faithful projection of the phenomena occurring in direct zone of the contact of screw-nut pair. The application of global equivalent models of the whole joint is necessary in order to make it possible to precisely determine internal loads in individual bolts and then local models to establish stress fields necessary to assign durability. Calculation methodology based on the construction of two coherent models has been described: global - for the entire flange joint, and local - for a single bolt joint. The elaborated methodology was applied to evaluate a flange joint in a heat exchanger with rotating heating surfaces that was subject to damage. The causes of damage of the flange joint were determined.

The rotation joint of the single-bucket excavator body consists of a torque slewing bearing subjected to a compound set of loads. Component elements of this joint form a coherent system, therefore independent selection of individual elements is not possible. The article describes the application of the finite element method for obtaining a solution, along with a description of how an appropriate model is to be built. It also presents and discusses sample results.

Designing a telescopic jib mounted on a mobile platform requires a range of calculations, including jib profile selection, definition of the stable area of operation etc. These calculations can be supplemented by FEM strength analysis, which allows for quicker construction design optimization.

The article presents the method of selection of measuring points on the elements of the rear drive axle in order to identify the maximum loads occurring when the bus is both empty and filled with passengers. Selected waveforms recorded during measurements are also presented.