Computing Gripping Points in 2D Parallel Surfaces Via Polygon Clipping

To generate suitable grasping positions between tessellated handling objects and specific planar grippers, we propose a 2D analytical approach which uses a polygon clipping algorithm to generate detailed information about the intersection between both objects. With the generated knowledge about the intersection we check whether its shape fits to the set criteria of the operator and represents a valid grasping position. Before the polygon clipping algorithm is applied, a preprocessing step is performed, where appropriate surfaces from the handling object and the gripper are extracted. After rotating all surfaces into a common plane, potential clipping positions are detected and the clipping is performed to get an accurate intersection detection. The validation shows comparable running times to a OBBTree algorithm (0.1 ms per grasping position) while increasing the stability of the results from 30 to 100% for the evaluated test objects.

Imagining Extinction inside Viral Body without Organs

Virus, in the form of a preassigned body without organs, predates the arrival of human species, and evolved on earth approximately three billion years ago, currently having an estimated variation of hundred million types. Humans form an insignificant subsection of the ‘virosphere’ (Crawford). Equipped with the knowledge of all organisms, the SARS-CoV-2 (my focus in this paper) virus combines with angiotensin-converting enzyme 2 (ACE2) which in turn identifies the tissues vulnerable to the infection. Once in the cell, it expropriates the cell’s mechanism, makes numerous copies of itself and invades other cells. Immune cells in the battle against the virus disrupt the flow of oxygen to all other parts of the body. In most cases, there is inflammation of the alveolus, its broken walls lessen oxygen intake, and the patient ends up in the ventilator. Eventually, the virus strikes all the organs with differing intensities– the lungs, the heart, the brain, the kidneys, the gut, the eyes. The animal virus merging with its human counterpart mirrors “interkingdoms, unnatural participations” where “Nature operates– against itself” (Deleuze and Guattari). Virus is anti-genealogy. Viruses bring the human and the non-human others together in a rhizomatic relation where genetic information and DNA are exchanged. Viruses, as BwO, de-structure the essential frame and subjectivity of humans. Both the human individual and viruses share a common plane where none possesses any essential reality and unfolds as an interactive space for multiple organic and inorganic exchanges. The only “enemy” of the virus is the organism, and as indeterminate, pure lawlessness it attacks the fundamental organization– the cellular and the molecular. Like the body without organs, viruses are anonymous/acephalous with its undying insistence to repeat/multiply and maximize connections. Virus is pure desire oriented towards reducing the infected body to its elemental form (compost/ash and others). Each organ transmutes into a body reacting against other bodies and against the whole body containing all organs. Claire Colebrook observes that a virus is so alive, “so lacking in boundaries and limits” that it does not qualify as a living being. My paper seeks to investigate the role of the virus in reducing/expanding the human to such an extent that it becomes one with the ground, and returns to its originary existence. I further propose that pandemics throughout history have initiated a re-imagination of human continuance; pandemics activate the human-toward-extinction by inducing the immortal virus through (consumed/to be consumed/ living) animals within the human.

The Step Feed Mechanisms For Auger Machines

The paper presents the results of studies of technical solutions proposed in Kuzbass State Technical University and implemented in auger drilling equipment, characterized by the presence of a cyclic feed of a boring machine on the face and the corresponding reverse of the work by hydraulic jacks. Operation of complexes, which design feature is to provide a common plane for the axis of the boring hole and vectors of axial forces of the auger feeding mechanisms, was researched. The stress state of the cyclic step-feeding mechanism’s functional elements by mathematical and software means of the finite element analysis is considered. The threshold values of the feed forces are determined from the point of view of ensuring the safety margin of welded joints used in the cyclic step-feeding mechanism’s structure, and from the point of operational reliability of the system as a whole. The obtained data allowed making recommendations for further improvement for the subsystem of the auger’s cyclic step-feeding mechanism.

Improvement of resolution in aperture synthesis in near zone of radiation based on the application of the Prony’s method

Applicability of inverse filtering with evolution control for reconstruction of images obtained by aperture synthesis technique is considered. A horn antenna, which is moved in the transversal direction, is used in order to obtain a 2-dimensional image. Scanned structure consists of one or two similar metaplates. In the latter case the plates are coplanar and their common plane is parallel to the aperture of the antenna. Regularisation coefficients are found with the help of trial and error method. The image of a single plate was used to tune the software. The Prony’s method is tested as a separate way of estimation of the distance between the plates. Both methods are tested for a range of different distances between the plates and between the plates’ common plane and aperture of the antenna. It is shown that inverse filtration tends to provide better results if the scanned object is situated further from the antenna. Said method was proven to be precise enough to distinguish closely-spaced plates. The Prony’s method was proven to provide reliable distance measurements if it was tuned correctly.

MEASURING IN IMAGES WITH PROJECTIVE GEOMETRY

<p><strong>Abstract.</strong> There is a fundamental relationship between projective geometry and the perspective imaging geometry of a pinhole camera. Projective scales have been used to measure within images from the beginnings of photogrammetry, mostly the cross-ratio on a straight line. However, there are also projective frames in the plane with interesting connections to affine and projective geometry in three dimensional space that can be utilized for photogrammetry. This article introduces an invariant on the projective plane, describes its relation to affine geometry, and how to use it to reduce the complexity of projective transformations. It describes how the invariant can be use to measure on projectively distorted planes in images and shows applications to this in 3D reconstruction. The article follows two central ideas. One is to measure coordinates in an image relatively to each other to gain as much invariance of the viewport as possible. The other is to use the remaining variance to determine the 3D structure of the scene and to locate the camera centers. For this, the images are projected onto a common plane in the scene. 3D structure not on the plane occludes different parts of the plane in the images. From this, the position of the cameras and the 3D structure are obtained.</p>

Temperature simulation of surface worked at combined flat peripheral grinding

A procedure is developed and the initial and boundary conditions of surface temperature computer simulation at combined and common plane grinding are defined. Dependences connecting the temperature of a surface worked with the value of allowance cut off, a line feed and a cross-feed of a blank are defined on the basis of which a mode of combined flat peripheral grinding ensuring the elimination of thermal damages of a surface layer worked is set.

Image stitching for construction of seabed mosaics

Решается задача сшивки фотографических изображений при построении карт морского дна на основе известных положений и ориентаций камеры автономного необитаемого подводного аппарата и расположения характерных (особых) точек на дне. Рассматриваются два алгоритма: простая сшивка, когда участок дна, видимый на каждом изображении, аппроксимируется плоскостью, и сшивка на основе трехмерной модели дна. Purpose. Seabed mosaics are built of tens of thousands of images obtained by the AUV at a small distance from the bottom. The height of the survey is limited by the power of the AUV lighting equipment and the transparency of the water and is often comparable with the differences in the heights of the bottom. This leads to strong distortions caused by parallax, which makes standard stitching methods inapplicable to the construction of photographic maps of the bottom with a complex relief. Methodology. The article proposes to consider the problem of constructing seabed mosaics as a problem of 3D reconstruction. Two approaches to stitching images are described: simple stitching and based on a 3D bottom model. With simple stitching, the relief represented by each image is approximated by a plane that is then projected onto the common plane of the seabed mosaic. When stitching based on a 3D model, the bottom section model is first constructed using the Delaunay triangulation, and then each triangle of the model is projected onto the plane of the map using a graphic accelerator GPU. To mix colors, a simple method of weighting the pixels of images is used, depending on their distance from the edges of the image. Findings. Stitching algorithms proposed in the paper were tested on images obtained by both real AUV and synthetic images. This allowed us to verify efficiency of stitching algorithms for conditions of a highly complex relief. In combination with simple color blending techniques, proposed algorithms have shown their practical efficiency. The stitching algorithm, based on the 3D model demonstrated its robustness to distortions caused by parallax. Originality/value. The main advantage of described approach is an absence of necessity to use computationally consuming, nontrivial color blending techniques while constructing seabed mosaics in the case of complex bottom relief.

A Trace of Similarity within Even Greater Dissimilarity

This article readdresses the Przywara-Barth controversy concerning analogia entis. The main point of our analysis is the question of whether the concept of analogy presented by Erich Przywara was in line with the classical Aristotelian-Thomistic definition and use of analogy in theistic predication. First, we ask about Przywara’s strong conviction that analogy is primarily a metaphysical and not merely a grammatical doctrine. Secondly, after presenting the complexity of Aquinas’ notion of analogy, as well as the variety of opinions on this subject among his commentators, we analyze (1) the objectives of Przywara’s view of analogia entis, (2) his grounding it in the terminology taken from the typology offered by Cajetan and juxtaposing analogia proportionalitatis and analogia atributionis, and (3) his introduction of the concept of “a new ‘attributive analogy’” proceeding from above to below and sustaining the tension within analogia entis. We show that Przywara remained a faithful student and interpreter of Thomas, where this makes Barth’s accusation that the Catholic doctrine of analogia entis puts God and creatures on a common plane of being unjustified.

Crystallographic features of the martensitic transformation and their impact on variant organization in the intermetallic compound Ni50Mn38Sb12studied by SEM/EBSD

The mechanical and magnetic properties of Ni–Mn–Sb intermetallic compounds are closely related to the martensitic transformation and martensite variant organization. However, studies of these issues are very limited. Thus, a thorough crystallographic investigation of the martensitic transformation orientation relationship (OR), the transformation deformation and their impact on the variant organization of an Ni50Mn38Sb12alloy using scanning electron microscopy/electron backscatter diffraction (SEM/EBSD) was conducted in this work. It is shown that the martensite variants are hierarchically organized into plates, each possessing four distinct twin-related variants, and the plates into plate colonies, each containing four distinct plates delimited by compatible and incompatible plate interfaces. Such a characteristic organization is produced by the martensitic transformation. It is revealed that the transformation obeys the Pitsch relation ({0{\overline 1}{\overline 1}}A// {2{\overline 2}{\overline 1}}Mand 〈0{\overline 1}1〉A// 〈{\overline 1}{\overline 2}2〉M; the subscripts A and M refer to austenite and martensite, respectively). The type I twinning planeK1of the intra-plate variants and the compatible plate interface plane correspond to the respective orientation relationship planes {0{\overline 1}{\overline 1}}Aand {0{\overline 1}{\overline 1}}Aof austenite. The three {0{\overline 1}{\overline 1}}Aplanes possessed by each pair of compatible plates, one corresponding to the compatible plate interface and the other two to the variants in the two plates, are interrelated by 60° and belong to a single 〈11{\overline 1}〉Aaxis zone. The {0{\overline 1}{\overline 1}}Aplanes representing the two pairs of compatible plates in each plate colony belong to two 〈11{\overline 1}〉Aaxis zones having one {0{\overline 1}{\overline 1}}Aplane in common. This common plane defines the compatible plate interfaces of the two pairs of plates. The transformation strains to form the variants in the compatible plates are compatible and demonstrate an edge-to-edge character. Thus, such plates should nucleate and grow simultaneously. On the other hand, the strains to form the variants in the incompatible plates are incompatible, so they nucleate and grow separately until they meet during the transformation. The results of the present work provide comprehensive information on the martensitic transformation of Ni–Mn–Sb intermetallic compounds and its impact on martensite variant organization.

A tool for automatic recognition of [110] tilt grain boundaries in zincblende-type crystals

The local atomic structure of [110] tilt grain boundaries (GBs) formed in ∼100 nm-sized GaAs nanocrystals, which crystallize in the non-centrosymmetric zincblende-type structure with face-centred cubic lattice symmetry, was imaged and analysed by means of high-resolution high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). The nanocrystals were grown by metal–organic vapour phase epitaxy on top of (001) Si nanotips embedded in an oxide matrix. This paper introduces an automatic analysis method and corresponding processing tool for the identification of the GBs. The method comprises (i) extraction of crystallographic parameters,i.e.misorientation angles and transformation matrices for the different crystal parts (grains/twins) observed by HAADF-STEM, and (ii) determination of their common plane(s) by modelling all possible intersections of the corresponding three-dimensional reciprocal lattices. The structural unit model is also used to characterize the GB structures and to validate the data obtained by the developed algorithm.