Marco Fritzsche

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The presented investigations build on the results already presented at EOSAM 2022 on the in-situ monitoring of grinding processes, in which high correlations between vibrometry, force and topography data of machined fused silica samples could already be proven. With the help of new measurement setups, it was possible to also detect high-frequency v...

The presented investigations deal with real-time evaluation and recording of vibrations and forces during a CNC grinding process, as well as the analysis and control of process influences on the surface quality of optical components. The experiments were carried out on a 5-axis CNC machine. Rapid subsequent analysis of the topography resulting from...

For fulfilling the demand of durable yet lightweight electrical connections in transportation industries, ultrasonic metal welding (USMW) sees widespread use in these branches. As the ultrasound oscillations utilized in the welding procedure occur at a range of only a few micrometers at frequencies of 20–100 kHz for an overall duration of only 50–1...

Inorganic non-metallic materials are widely used in many application areas such as precision optics, semiconductor technology, high-temperature technology or medical technology. This increasingly requires the application of precise multi-axis CNC machine technology and poses great challenges for the machining processes, especially with regard to th...

Friction stir welding (FSW) is an innovative solid-state joining process, which is suitable for joining dissimilar materials with strongly differing physical and chemical properties such as aluminum and steel. Where other joining methods such as fusion welding struggle to achieve appropriate joint strengths due to the excessive formation of brittle...

Micro/nano thermogravimetry (TG) employing MEMS has significant potential to improve the minimum sample mass and mass resolution as compared to commercial TG instruments. Although there have been a few previous reports on MEMS TG, none of them have critically analysed the obtained TG curve in detail. In this work, we have designed and fabricated a...

The presence of high-frequency velocity fluctuations in aneurysms have been confirmed by in-vivo measurements and by several numerical simulation studies. Only a few studies have located and recorded wall vibrations in in-vitro experiments using physiological patient models. In this study, we investigated the wall fluctuations produced by a flowing...

A novel (to our knowledge) approach for resolution improvement in digital holography is presented in this paper. The proposed method is based on recording the incoming interference field on a complementary metal-oxide semiconductor (CMOS) camera with subpixel resolution. The method takes advantage of the small pixel size of the CMOS sensor, while o...

For more than 20 years Laser Doppler Vibrometry (LDV) is an established tool in vibration engineering for non-contact vibration measurements. The LDV method is not only limited to measurements on single test points. Utilizing a pair of galvanoelectrical mirrors for steering the laser beam in x and y directions across the surface the vibration patte...

In digital holography the sinusoidal interference pattern resulting from the interference between reference and object-wave is stored on a digital receiver, such as CCD or CMOS cameras. The maximum resolution of such receivers (typically 500 lp/mm) is small compared to the typical resolution of photographic plates (3000 lp/mm) originally used in op...

A novel approach for the fabrication of diffractive optical elements is described. This approach is based on an interferometric phase contrast method that transforms a complex object wavefront into an intensity pattern. The resulting intensity pattern is used to expose a photoresist layer on a substrate. After development, a diffractive phase objec...