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Galaxies, 2021 There are a number of publications on relativistic objects dealing either with black holes or naked singularities in the center. Here we show that there exist static spherically symmetric solutions of Einstein equations with a strongly nonlinear scalar ...
Oleksandr Stashko, Valery I. Zhdanov
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Overcoming Kinematic Singularities for Motion Control in a Caster Wheeled Omnidirectional Robot
Robotics, 2021 Omnidirectional planar robots are common these days due to their high mobility, for example in human–robot interactions. The motion of such mechanisms is based on specially designed wheels, which may vary when different terrains are considered. The usage
Oded Medina, Shlomi Hacohen
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On singularities of real algebraic sets and applications to kinematics
Open Mathematics, 2020 We address the question of identifying non-smooth points in Vℝ(I){{\bf{V}}}_{{\mathbb{R}}}(I) the real part of an affine algebraic variety. Two simple algebraic criteria will be formulated and proven.
Diesse Marc
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Singularities of Serial Robots: Identification and Distance Computation Using Geometric Algebra
Mathematics, 2022 The singularities of serial robotic manipulators are those configurations in which the robot loses the ability to move in at least one direction. Hence, their identification is fundamental to enhance the performance of current control and motion planning
Isiah Zaplana +2 more
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Electronic Journal of Qualitative Theory of Differential Equations, 2014 In this article we obtain the geometric classification of singularities, finite and infinite, for the three subclasses of quadratic differential systems with $m_f=4$ possessing exactly two finite singularities, namely: (i) systems with two double complex
Joan Artés +4 more
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On singularity confinement for the pentagram map [PDF]
Discrete Mathematics & Theoretical Computer Science, 2012 The pentagram map, introduced by R. Schwartz, is a birational map on the configuration space of polygons in the projective plane. We study the singularities of the iterates of the pentagram map.
Max Glick
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Electronic Journal of Qualitative Theory of Differential Equations, 2015 In this article we obtain the geometric classification of singularities, finite and infinite, for the two subclasses of quadratic differential systems with total finite multiplicity $m_f=4$ possessing exactly three finite singularities, namely: systems ...
Joan Artés +3 more
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Architectural singularities of parallel mechanisms with prismatic joints due to special designs of platform shapes [PDF]
Mechanical Sciences, 2019 Singularity is an inherent property of robotic manipulators. A manipulator becomes singular when it gains or losses degrees of freedom at a particular configuration.
X. Wu, S. Bai
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Kinematics and Singularity Analysis of a 7-DOF Redundant Manipulator
Sensors, 2021 A new method of kinematic analysis and singularity analysis is proposed for a 7-DOF redundant manipulator with three consecutive parallel axes. First, the redundancy angle is described according to the self-motion characteristics of the manipulator, the ...
Xiaohua Shi +4 more
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Electronic Journal of Qualitative Theory of Differential Equations, 2017 In the article [C. Bujac, J. Llibre, N. Vulpe, Qual. Theory Dyn. Syst. 15(2016), 327–348] for the family of cubic differential systems with the maximum number of invariant straight lines, i.e.
Cristina Bujac, Nicolae Vulpe
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