Michael Somr

University of Freiburg | Albert-Ludwigs-Universität Freiburg

Modular designs have gained popularity because they can address manufacturing efficiency, reusability, and sustainability concerns without sacrificing performance compared to traditional non-modular counterparts. This work explores modular compliant mechanisms in this context. We present a manufacturing-aware design procedure composed of three cons...

In this paper, we introduce a novel design paradigm for modular architectured materials that allows for spatially nonuniform designs from a handful of building blocks, which can be robotically assembled for efficient and scalable production. The traditional, design-limiting periodicity in material design is overcome by utilizing Wang tiles to achie...

In this paper, we introduce a novel design paradigm for modular architectured materials that allows for spatially nonuniform designs from a handful of building blocks, which can be robotically assembled for efficient and scalable production. The traditional, design-limiting periodicity in material design is overcome by utilizing Wang tiles to achie...

Introducing the principles of circular economy into the concrete industry would significantly contribute to the sustainability of this sector. Even though recycling ranks below waste elimination, the generation of concrete waste is inevitable, and modern recycling strategies cannot efficiently tackle waste concrete fines (WCF) that represent an eno...

Caldera collapse represents severe volcanic hazards for the environment, climate, and human society, but it can also be beneficial as it may contribute to the formation of ore deposits and produce fertile soils. A deeper understanding of mechanical conditions under which caldera collapse can occur is thus of great importance and interest and can be...

Widespread demand for mobile robots is pushing the research envelope for the development of new robot driving mechanisms that can handle diverse environments. Bristle-bot- like robot designs, investigated increasingly over the past decade, are based on vibration mechanisms built on flexible legs that enable motion on the ground. However, creating s...

The emerging field of passive macro-scale tile-based self-assembly (TBSA) shows promise in enabling effective manufacturing processes by harnessing TBSA's intrinsic parallelism. However, current TBSA methodologies still do not fulfill their potentials, largely because such assemblies are often prone to errors, and the size of an individual assembly...

The emerging field of passive macro-scale tile-based self-assembly (TBSA) holds promise for enabling effective manufacturing processes by harnessing TBSA's intrinsic parallelism. However, the current TBSA methodology still does not fulfill its potential, largely because such assemblies are typically error-prone and the size of an individual assembl...

The combined efforts of theoretical computer science, biochemistry, and nanotechnology have enabled the design of tile-based systems capable of self-assembling intricate patterns in a massively parallel manner, with low error rates, and applications ranging from DNA computing to microelectronics. However, as the underlying physical and chemical pri...

An open-source tool for a real-time measurement of relative displacements based on image registration is presented. The use of upsampled matrix-multiplication discrete Fourier transform and measurement limited to predefined points of interest by virtual extensometers allows high sampling frequencies with a subpixel accuracy. This solution was desig...

Calderas are volcanic depressions caused by rupturing of a magma chamber roof as a consequence of pressure evolution inside the chamber. The collapse of a caldera is accommodated by ring faults, whose formation is commonly accompanied by ejection of large volumes of pyroclastic material to the Earth’s atmosphere and thus represents severe volcanic...

A concept of a planar modular mechanical metamaterial inspired by the principle of local adaptivity is proposed. The metamaterial consists of identical pieces similar to jigsaw puzzle tiles. Their rotation within assembly provides a substantial flexibility in terms of structural behavior, whereas mechanical interlocks enable reassembly. The tile de...

A comprehensive study consisting of a microstructure investigation, nanoindentation, and mi-cromechanical modeling was performed to identify phases and assess their impact on macro-scopic properties of cement pastes containing waste marble powder. The proposed model, built on the Mori-Tanaka scheme, was used to estimate the effective Young's modulu...

A concept of a planar modular mechanical metamaterial inspired by the nature's principle of local adaptivity is proposed. The metamaterial consists of identical pieces similar to jigsaw puzzle tiles. Their rotation within assembly provides a substantial flexibility in terms of structural behavior and mechanical interlocks enable reassembly. The til...

In this contribution, we design a minimum-weight truss reinforcement of a thin-walled composite beam, such that the fundamental free-vibrations eigenfrequency of the beam is increased to a specific value. The reinforcement structure is designed using techniques of topology optimization and produced using additive manufacturing, in order to achieve...

We present a cheap solution for assessment of contact angles on sessile drops or menisci formed around partially submerged fibers. The proposed system consists of a simple optical set combined with an open-source software CAMTIA. The fully automatic assessment of contact angles is based on image binarization, identification of regions of interest,...

Cost of experimental testing of materials and structures subjected to mechanical loading often constitutes a significant portion of a project budget. Therefore a collection of data in a maximum possible amount is desirable. Extensometers and strain-gauges attached to the specimen surface often fail and cannot provide full-field information about th...

This study integrates gravimetry and thermal modelling with petrology, U–Th–Pb monazite and zircon geochronology and whole-rock geochemistry of the early Carboniferous Říčany Pluton, Bohemian Massif, in order to discuss the origin of compositional and textural zoning in granitic plutons and complex histories of horizontally stratified, multiply rep...

Gravity-driven failure of shallow magma chamber roofs and formation of collapse calderas are commonly accompanied by ejection of large volumes of pyroclastic material to the Earth's atmosphere and thus represent severe volcanic hazards. In this respect, numerical analysis has proven as a key tool in understanding the mechanical conditions of calder...

Preliminary outcomes on a novel modular additive manufacturing technology are presentedin this contribution. The capabilities of the proposed system to synthesize materials with conventionalor meta properties are explored. Two limiting and a single mixed compositions are tested in com-pression in order to reveal both, global and local behaviours of...

The purpose of this study is to demonstrate the influence of plasma treatment on the surface properties of PET fibers used as micro reinforcement in cementitious composites. The stress transfer across cracks that untreated fibers are able to accomplish can be enhanced via plasma treatment. The increase in surface roughness and the activation of pol...

The formation of a caldera poses a serious risk for the society and the environment. There are several established processes (mostly dealing with the conditions inside the reservoir), which must take place in order to reach a collapse leading to the caldera. The role of magma chamber geometry is investigated in this paper, exploiting the numerical...

The paper deals with homogenization and strength estimation of mortars containing crushed bricks or other clay products. These mortars, known as cocciopesto, were used mainly during the Byzan-tine period and by Romans. Cocciopesto exhibit quite extraordinary mechanical properties due to formation of C-S-H gel coating on the interface between lime m...