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Abstract

In the paper the topic of Building Information Technology BIM is investigated. It is new in Polish circumstances technology for construction and for building product industry, which contribute to change and develop level of industrialization. Especially challenge raising from the information and introducing IT technology into daily practice is considered to provide changes in construction branch of economy. In Poland there is the hot need of start to introduce BIM as the common technology for owners of assets, facility management, construction entities, design offices, administration officers and many other players relative to construction data and processes. BIM technology introduction, basing on foreign case studies, results in cost savings, control and time reduction of investment processes and some more advantages. The perspective of digital buildings, digital infrastructure, digital roads, digital railways and digital cities is outlined at the perspective of technology challenge, but simply transfiguration of many fields of personal everyday life, where digitalization is already present and with the question when it will be common in professional activity, particularly in civil engineering.
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Abstract

Neutralisation of the terrorist explosive devices is a risky task. Such tasks may be carried out by robots in order to protect human life. The article describes chosen design problems concerning the new neutralisation and assisting robot SMR-100 Expert. The robot was to be designed for the use in confined spaces, particularly inside the air-crafts, buses and rail cars. In order to achieve this ambitious plan, new advanced technological designing tools had to be applied. A number of interesting design issues were approached. The successful development of the prototype robot Expert in Poland resulted in the creation of the first intervention robot in the world able to perform all necessary anti-terrorist tasks inside the passenger planes.
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Abstract

This paper is a case study conducted to present an approach to the process of designing new products using virtual prototyping. During the first stage of research a digital geometric model of the vehicle was created. Secondly it underwent a series of tests utilising the multibody system method in order to determine the forces and displacements in selected construction nodes of the vehicle during its movement on an uneven surface. In consequence the most dangerous case of loads was identified. The obtained results were used to conduct detailed strength testing of the bicycle frame and changes its geometry. For the purposes of this case study two FEA software environments (Inventor and SolidWorks) were used. It has been confirmed that using method allows to implement the process of creating a new product more effectively as well as to assess the influence of the conditions of its usage more efficiently. It was stated that using of different software environments increases the complexity of the technical process of production preparation but at the same time increases the certainty of prototype testing. The presented example of simulation calculations made for the bicycle can be considered as a useful method for calculating other prototypes with high complexity of construction due to its systematized character of chosen conditions and testing procedure. It allows to verify the correctness of construction, functionality and perform many analyses, which can contribute to the elimination of possible errors as early as at the construction stage.
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Abstract

In this paper, a novel structure of a compact UWB slot antenna and its design optimization procedure has been presented. In order to achieve a sufficient number of degrees of freedom necessary to obtain a considerable size reduction rate, the slot is parameterized using spline curves. All antenna dimensions are simultaneously adjusted using numerical optimization procedures. The fundamental bottleneck here is a high cost of the electromagnetic (EM) simulation model of the structure that includes (for reliability) an SMA connector. Another problem is a large number of geometry parameters (nineteen). For the sake of computational efficiency, the optimization process is therefore performed using variable-fidelity EM simulations and surrogate-assisted algorithms. The optimization process is oriented towards explicit reduction of the antenna size and leads to a compact footprint of 199 mm2 as well as acceptable matching within the entire UWB band. The simulation results are validated using physical measurements of the fabricated antenna prototype.
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Abstract

Geometric deviations of free-form surfaces are attributed to many phenomena that occur during machining, both systematic (deterministic) and random in character. Measurements of free-form surfaces are performed with the use of numerically controlled CMMs on the basis of a CAD model, which results in obtaining coordinates of discrete measurement points. The spatial coordinates assigned at each measurement point include both a deterministic component and a random component at different proportions. The deterministic component of deviations is in fact the systematic component of processing errors, which is repetitive in nature. A CAD representation of deterministic geometric deviations might constitute the basis for completing a number of tasks connected with measurement and processing of free-form surfaces. The paper presents the results of testing a methodology of determining CAD models by estimating deterministic geometric deviations. The research was performed on simulated deviations superimposed on the CAD model of a nominal surface. Regression analysis, an iterative procedure, spatial statistics methods, and NURBS modelling were used for establishing the model.
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Abstract

A new Computer-Aided Design approach is introduced for design of steel castings taking into account the feeding ability in sand moulds. This approach uses the geometrical modeling by a CAD-program, in which the modul “Castdesigner” is implemented, which includes the feeding models of steel castings. Furthermore, the feeding ability is guaranteed immediately during the design by an interactive geometry change of the casting cross section, so that a directional feeding of the solidifying casting from the installed risers is assured.
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Abstract

The paper presents the development procedures for both virtual 3D-CAD and material models of fractured segments of human spine formulated with the use of computer tomography (CT) and rapid prototyping (RP) technique. The research is a part of the project within the framework of which a database is developed, comprising both 3D-CAD and material models of segments of thoracic-lumbar spine in which one vertebrae is subjected to compressive fracture for a selected type of clinical cases. The project is devoted to relocation and stabilisation procedures of fractured vertebrae made with the use of ligamentotaxis method. The paper presents models developed for five patients and, for comparison purposes, one for a normal spine. The RP material models have been built basing on the corresponding 3D-CAD ones with the use of fused deposition modelling (FDM) technology. 3D imaging of spine segments in terms of 3D-CAD and material models allows for the analysis of bone structures, classification of clinical cases and provides the surgeons with the data helpful in choosing the proper way of treatment. The application of the developed models to numerical and experimental simulations of relocation procedure of fractured vertebra is planned.
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