Search Results - "Stachel, Hellmuth"

The geometry of billiards in ellipses and their poncelet grids by Stachel, Hellmuth

“…The goal of this paper is an analysis of the geometry of billiards in ellipses, based on properties of confocal central conics. The extended sides of the…”
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On the motion of billiards in ellipses by Stachel, Hellmuth

“…For billiards in an ellipse e with an ellipse as caustic, there exist canonical coordinates on e such that the billiard transformation from vertex to vertex is…”
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Recalling Ivory's theorem by Stachel, Hellmuth

“…Ivory's Theorem states that in each curvilinear quadrangle of a confocal net of conics the two diagonals have the same lengths. This theorem is valid not only…”
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Area-invariant pedal-like curves derived from the ellipse by Reznik, Dan, Garcia, Ronaldo, Stachel, Hellmuth

“…We study six pedal-like curves associated with the ellipse which are area-invariant for pedal points lying on one of two shapes: (i) a circle concentric with…”
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Flexible Polyhedral Surfaces with Two Flat Poses by Stachel, Hellmuth

“…We present three types of polyhedral surfaces, which are continuously flexible and have not only an initial pose, where all faces are coplanar, but pass during…”
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STROPHOIDS, A FAMILY OF CUBIC CURVES WITH REMARKABLE PROPERTIES by STACHEL Hellmuth

“…Strophoids are circular cubic curves which have a node with orthogonal tangents. These rational curves are characterized by a series or properties, and they…”
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On the computation of foldings by Stachel, Hellmuth

“…The process of determining the development (or net) of a polyhedron or of a developable surface is called unfolding and has a unique result, apart from the…”
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THE LOGARITHMIC SPIRAL AND ITS SPHERICAL COUNTERPART by Hellmuth STACHEL, Giorgio FIGLIOLINI, Jorge ANGELES

“…Logarithmic spirals are isogonal trajectories of pencils of lines. From a series of geometric consequences, we pick out a few which are relevant for…”
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Equicevian Points of a Triangle by Sadi Abu-Saymeh, Mowaffaq Hajja, Hellmuth Stachel

“…A point P in the plane of a given triangle ABC is called equicevian if the cevians AA P , BB P , and CC P through P are of equal length. In this note we prove…”
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The man who invented descriptive geometry by Cvetković, Ivana, Stojićević, Miša, Stachel, Hellmuth, Milićević, Rodoljub, Popkonstantinović, Branislav

“…Gaspard Monge is known as the father of modern descriptive and differential geometry. In 1764, he was engaged to draw a detailed plan of a fortification in his…”
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A CANAL SURFACE CONTAINING FOUR STRAIGHT LINES by Hellmuth STACHEL

“…A canal surface is the envelope of spheres with centers traversing a spatial curve called spine curve. The spheres contact the envelope along so-called…”
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A CANAL SURFACE CONTAINING FOUR STRAIGHT LINES by Hellmuth STACHEL

“…A canal surface is the envelope of spheres with centers traversing a spatial curve called spine curve. The spheres contact the envelope along so-called…”
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On the flexibility and symmetry of overconstrained mechanisms by Stachel, Hellmuth

“…In kinematics, a framework is called overconstrained if its continuous flexibility is caused by particular dimensions; in the generic case, a framework of this…”
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On the flexibility and symmetry of overconstrained mechanisms by Stachel, Hellmuth

“…In kinematics, a framework is called overconstrained if its continuous flexibility is caused by particular dimensions; in the generic case, a framework of this…”
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A kinematic approach to Kokotsakis meshes by Stachel, Hellmuth

“…A Kokotsakis mesh is a polyhedral structure consisting of an n-sided central polygon P 0 surrounded by a belt of quadrangles or triangles in the following way:…”
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Kinematic properties of planar and spherical logarithmic spirals: Applications to the synthesis of involute tooth profiles by Figliolini, Giorgio, Stachel, Hellmuth, Angeles, Jorge

“…•Kinematic synthesis of planar and spherical involute tooth profiles.•Application of Camus theorem using the logarithmic spiral as auxiliary…”
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HIGHER ORDER FLEXIBILITY OF OCTAHEDRA by Stachel Hellmuth

“…More than hundred years ago R. Bricard determined all continuously flexible octahedra. On the other hand, also the geometric characterization of first-order…”
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A planar parallel 3-RRR robot with synchronously driven cranks by Can, Engin, Stachel, Hellmuth

“…This paper focuses on the analysis and synthesis of F-mechanisms, i.e., of planar parallel 3-RRR robots with three synchronously driven cranks. These are…”
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STROPHOIDS, A FAMILY OF CUBIC CURVES WITH REMARKABLE PROPERTIES by Hellmuth Stachel

“…Strophoids are circular cubic curves which have a node with orthogonal tangents. These rational curves are characterized by a series or properties, and they…”
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STROPHOIDS, A FAMILY OF CUBIC CURVES WITH REMARKABLE PROPERTIES by Hellmuth Stachel

“…Strophoids are circular cubic curves which have a node with orthogonal tangents. These rational curves are characterized by a series or properties, and they…”
Get full text