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The power pattern of a corrugated horn antenna designed for low sidelobes was measured to levels 90 dB below the main beam maximum in both the E-and H-planes. The measured patterns were found to be in good agreement with theoretical predictions.

Gearing is one of the most important rolling nodes in a cycloidal planetary transmission. It consists of gears whose outlines are created according to cycloidal curves and the rollers cooperating with them. The epicycloidal and hypocycloidal gearing can be distinguished. There are power losses during the transmission operation, due to the transmitted load and friction in the gearing. The paper presents an analytical method for determining losses in cycloidal gearing, taking into account the manufacturing deviations of the elements making this gearing. The analysis allowed determining the distribution of intertooth clearances and forces at the points of contact between the profiles and the rollers, and consequently the distribution of power losses in gearing. The distribution of intertooth forces was verified by elastooptic tests of the gears set with cycloidal gearing. The results of the calculations indicate that the influence of eccentricity changes on the distribution of intertooth forces is significant and also that the distribution of power losses in gearing is closely related to the distribution of intertooth forces and has a very similar character.

The gerotor pump has many advantages over other hydraulic pumps, such as high reliability, compactness, lower noise in running conditions etc. Considering the increasingly stringent regulations in the field of environmental protection, one of the main goals in the industrial applications of gerotors is to improve their design by using light materials and optimize their performance. This paper will give an overview of modern research that focuses on improving the performance of gerotor pumps. A joint publication of three university centers, namely of Wroclaw, Terrassa and Kragujevac, presents their original approaches to the problem of designing gerotor and orbital systems. The presentations have been prepared in separate parts, but according to similar rules. The first part of the paper focuses on meshing between internal and external gear of gerotor. Analysis for both cases, moved axis and fixed axis, will be provided in accordance to their working characteristics and their application. The second part of the paper provides the design of a gerotor pump strikes a balance between volumetric efficiency, manufacturability and mechanical efficiency. The third part of the paper defines the methodology for selecting the best combination of geometric form parameters of the trochoidal gearing in relation to the reduction of contact stresses and improving other characteristics of the pump. All three parts provide manufacturing and application review in the fluid power machines. Paper concludes with presented theoretical and experimental review of the authors and their practice achievements.