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The functional requirements of design structures, for example, the load capacity, reliability, service life, etc. are strongly related to operation conditions that are, as a rule, random and very often uncertain. The basic idea is to apply a set of methods in Engineering Design in order to develop a methodology for load capacity identification with regard to operation conditions. An automotive gearbox has been taken for the case study, because it represents a design structure with very variable operation conditions. The reliability of structures such as gearboxes is one of the main indicators of quality and an important functional requirement. In order to fulfil this objective, various methods and approaches are taken into consideration, such as Robust and Axiomatic Design, Property-based design, Design for X, and various studies in the fields of automotive gearboxes, gears and gear failures, the reliability of gear transmission components, etc.Today, Axiomatic design provides a basis for analytic presentation of the relationship between functional requirements and design parameters. The Axiomatic principles developed by Suh, continue to perfectly for various applications [1], but this methodology is also suitable for combining with the Robust Design approach. On the other hand, the Property-based design approach together with the system structure and functional requirements or quality indicators deduction provides possibilities for arranging specific procedures and approaches for the design parameters or the carrying capacity identification for design structures such as automotive gearboxes. Robust Design is a verified methodology, which provides good results on the first attempt. It also provides good design results (the relationship between functional requirements and design parameters) under variable operation conditions, and is applied for solving problems in many kinds of specific design cases. For horizontal axis wind turbines, the Robust design is carried out using the Taguchi method [2] and multi-objective optimization of the design parameters. The robustness of uncertain design variables can be provided by optimization using evolutionary algorithms [3]. The optimization is performed by analysing whether the solutions are truly robust and how robust optimal solutions differ from the performance maximizing solutions. Further perfection of robustness is provided for quality variables that vary over time [4]. Using the expectation of maximal quality loss over a time period, this work suggests the possibility of quantifying the robustness for timedependent quality characteristics. The reliability of technical systems such as automotive gearboxes is a typical time-dependent quality indicator that has to be treated in a similar way. In addition, the desired elementary reliability at the end of the service life of a design component can be applied as a design constraint for the design parameters definition [5] and [6].The reliability of technical systems has been studied for a long time, basically for the sake...

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Dynamic processes of the cranes with loading-unloading trolley on slewing platform are very complex and require certain simplifications, although efforts should be made to theoretically involve widest range of impacts, with respect to degree of importance of individual impacts. The study of the dynamic behavior of the cranes is very important in terms of precise determination of stress state, as well as the other characteristics of the elements and supporting structures. Dynamic loads of the cranes occur during periods of non-stationary operating regimes of any of its mechanisms. In this paper, we obtain the differential equations of motion of the cranes for some specific cases of movement, based on general multi-mass model of the crane with loading-unloading trolley on slewing platform.