Modern CAD/CAE allows supporting the process of design and construction at many stages, from concept development through specific engineering calculations to the creation of design documentation. In the case of constructing mechanisms, the kinematic and dynamic analysis of the proposed system is an important step in the introduced process. The paper presents an example of the kinematic and dynamic analysis of the Stewart platform using Siemens NX software [1, 2]. The conducted investigation has allowed determining the geometric characteristics of the mechanism of the Stewart platform as well as the geometric parameters of actuators and their location. A dynamic analysis of the platform helped with establishing the required motor forces for realizing the moves with the maximum speed and acceleration. This allowed the initial selection of the parameters of electric motors. Traffic analysis was also performed for investigating collisions between the parts of the hexapod and between the hexapod and its environment.

This article presents the results of an examination of the properties of arc-sprayed aluminum on alloyed armor-grade steel. Thermal arc spraying was conducted with a EuTronic Arc Spray 4 wire arc sprayer. Aluminum wire 1.6 mm in diameter was used to produce dense, abrasion- and erosion-resistant coatings approx. 1.0 mm thick with and without nickel/5% aluminum-buffered subcoating. Aluminum coatings were characterized in accordance with ASTM G 65-00 abrasion resistance test, ASTM G 76-95 erosion resistance tests, ASTM C 633-01 adhesion strength, HV0.1 hardness tests and metallographic analyses. Results demonstrate properties of arc-sprayed aluminum and aluminum-nickel material coatings that are especially promising in industrial applications where erosion-, abrasion- and corrosion-resistant coating properties are required.

The paper presents the results of virtual analysis of the stability of mining roof supports loaded by the roof rocks. The hydraulic roof support generally accounts for over 50% of the total value of a coal mining and excavating system. Many reports show that in some conditions roof supports behave differently than foreseen. To explain this phenomena the investigations basing on the virtual model were done [1,2]. This phenomena is very dangerous for miners because this behaviour of a mining roof support may cause dangerous accidents in coal mines. In the investigation process some questions have been asked. Firstly what type of a mining support is more liable to this behaviour. Secondly what work conditions are the most dangerous. To analyse this phenomena it was used models of two types of a mining support. One with two props and one with four ones. Results show that that the problem of plunged of roof parts of a support in the coal bed is consider with the construction of the support. The most dangerous is the roof support with two props. The consequences of this results are the recommendations to use rather supports with four props then two.

The paper presents the method of describing the conception of a future technical mean basing on the method of functional features. In order to determine the attributes which should characterize the functional features for the description of the conception of a technical mean it has been analyzed the different stages of the design-constructional-manufacturing process. Basing on the review of literature it was supposed the structure of the design-constructional-manufacturing process which includes the following stages: the need determination, designing, constructing, manufacturing and exploitation. In the process of designing-constructing-manufacturing one can distinguish models associated with each of its stages, and namely: the model related to designing (a conception), the model related to constructing (a construction), the model related to planning, the model related to manufacturing. The most important from mentioned models, in the terms of description of the conception of a technical mean, is the model related to the designing sub-process. It was assumed that the model related to the designing sub-process should include such information as: the structure of the system of a future technical mean (system of conjugations and transformations relationships), the design solutions of components of a technical system associated with the transformations relations, the design solutions of connections between components of s technical system mapping the established conjugations relationships between elements.

Recently the number of designed modular machine was increased. The term modular machine is used to denote different types of machinery, equipment and production lines, which are created using modular elements. Modular could be both mechanic elements, and drives, as well as control systems. This method of machine design is more and more popular because it allows obtaining flexible and relatively cheap solutions. So it is worth to develop the concept of modularity in next areas of application. The advantages of modular solutions are: simplification of the structure, standardization of components, and faster assembly process of the complete machine Additional advantages, which is particularly important for manufacturers, are shorter manufacturing times, longer production series and reduced manufacturing costs. Modular designing is also the challenge for designers and the need for a new approach to the design process, to the starting process and to the exploitation process. The purpose for many manufacturers is the standardization of the components used for creating the finished products. This purpose could be realized by the application of standard modules which could be combined together in different ways to create the desired particular construction as much as possible in accordance with the order. This solution is for the producer more favorable than the construction of a large machine whose configuration must be matched to each individual order. In the ideal case each module has its own control system and the full functionality of the modular machine is obtained due to the mutual cooperation of all modules. Such a solution also requires the modular components which create the modular machine are equipped with interfaces compatible one with another to facilitate their communication. The individual components of the machine could be designed, manufactured and used independently and production management task could be divided into subtasks. They could be also outsourced to an independent manufacturer. Standardization and run of the entire modular machine should be easier if standardized are individual modules. The advantages of modular design, in addition to those mentioned above, there are many more.