Except shape errors (low spatial frequencies) and microroughness (high spatial frequencies) on optical surface there also occur socalled mid spatial frequencies (MSF). Structures inside band MSF originate primarily during subaperture machining and significant role have vibrations inside machine-tool [1]. The subject of this article is a vibrodiagnostics of optical surface machining by CNC machine-tool and localization of effect of specific vibrational frequencies to the area on workpiece surface. and Kromě odchylek tvaru, tedy nízkých prostorových frekvencí, a mikrodrsnosti, tedy vysokých prostorových frekvencí, se na optickém povrchu taktéž vyskytují tak zvané střední prostorové frekvence. Struktury v pásmu středních prostorových frekvencí (MSF - mid spatial frequencies) vznikají především u subaperturního CNC obrábění a významnou roli u toho hrají vibrace uvnitř obráběcího stroje [1]. Předmětem tohoto článku je vibrodiagnostika obrábění optických ploch na CNC stroji a lokalizace působení konkrétních vibračních frekvencí na oblast na povrchu obrobku.
A problem of measuring tilt around a single axis is discussed in detail with regard to the resultant accuracy. Ways of improving the accuracy, based on application of various mathematical equations, are proposed. Presented results of related experimental studies, performed on a tilt sensor made of a standard MEMS accelerometer, have proven that it is possible to obtain accuracy of such measurements of ca. 0.2 degrees arc. Additionally, a problem of measuring tilt of an object, which rotates within a non-vertical plane, is addressed. and Obsahuje seznam literatury
Modern methods of monitoring landslides are based on observations of both: direct surveying (GNSS, electronic tachymetry, geometric levelling) and remote sensing (terrestrial and aerial photogrammetry, laser scanning, interferometry), as well as surface and subsurface geotechnical observations (e.g. inclinometers, extensometers, piezometers, etc.). Due to the high cost of installation of these devices and its measurement, the implementations of these methods are usually used on well-define d objects, with established landslide activity and high risk to people’s lives. The main objective of the project was to design, create and do practical tests of simple and inexpensive measurement devices, which detect first symptoms of a potential landslide movements and alert of an existing threat. These devices would be some kind of an early warning system that would register the occurrence of the first movements of the surface layers of soil, which would be a signal to start of geodetic and geotechnical monitoring of potential landslides., Bartłomiej Ćmielewski, Bernard Kontny and Kazimierz Ćmielewski., and Obsahuje bibliografické odkazy