Reliability of rotating machinery is determined to a considerable degree by the bearing units. For several applications the requirements in rotation speed, bearing load and maximal vibration level are so extreme that neither rolling-element bearings nor fluid-film bearings could provide necessary performance characteristics during all regimes of operation. Hybrid bearings, which are a combination of rolling-element and fluid-film bearings, can improve performance characteristics and reliability of the rotor-bearing systems. The aim of this work is to analyze the advantages and disadvantages of the hybrid bearings. Known real applications of hybrid bearings are discussed. Analysis shows that depending on the application different hybrid bearing types could improve dynamic characteristics and life time of the bearing unit, increase load capacity and DN limit of the rolling-element bearing.

Automation and using robotic means allows increasing industry efficiency, including construction. At the same time, important factors of applying such means are profitability and adaptability. The paper considers the basic parameters influencing the economic and technological efficiency of applying mobile bricklaying robots. The main aspects for comparing manual and automated labor are showed based on the acting standards and technical features of operation of such robots. It is offered to use a coefficient showing the ratio of brickwork volumes for bearing walls and for partitions of a constructed object for evaluation of efficiency of applying a bricklaying robot. As most buildings differ from each other, the modeling software for automated evaluation economic and technological parameters of construction is offered. Such software will include a model of operation of a bricklaying robot and will evaluate efficiency of different combinations of manual and automated labor during bricklaying.

The paper considers increasing effectiveness of construction of bricks and blocks by applying mobile masonry robots. On the example of a specific object, the rates for its construction using manual labor and robotic means are considered. The results show that applying robotic means allows reduce costs for bricklaying 3-7 times in comparison with manual labor depending on method of accruing salaries. Other positive effects of using bricklaying automation, such as reducing construction time, increasing the quality of the result and simplification of staff management, are considered.

Automation of bricklaying using mobile robots requires new solutions in many spheres, including developing new algorithms. A mobile bricklaying robot moving at a construction site is considered as a task of planning its trajectory. The task is partly similar to passing a maze but has some distinctive features. Analysis of required movements and analysis of structure of a typical masonry plan allows create an approach to building a moving algorithm for a bricklaying robot. The developed algorithms consist of two separate algorithms, one for moving while directly building walls, another for fast and effective travelling between two points of a map without laying bricks. The developed algorithm has to be tested for different masonry plans and may be optimized in the described ways.

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