3,260 research outputs found
Dataset and related MATLAB scripts for the IEEE ICRA 2021 paper "Predicting the Post-Impact Velocity of a Robotic Arm via Rigid Multibody Models: an Experimental Study"
No full textThis dataset contains impact data (recording of joint displacement encoders), together with related MATLAB scripts for visualization and post-processing, for several impact experiments performed on a KUKA IV+ collaborative robot colliding a wooden table with a spherical metallic end-effector. The dataset is associated to the "Predicting the Post-Impact Velocity of a Robotic Arm via Rigid Multibody Models: an Experimental Study" by Ilias Aouaj, Vincent Padois, and Alessandro Saccon, accepted to ICRA 2021
Bifurcation for variational inequalities with strongly indefinite quadratic part
No full textWe study the existence of bifurcation points for variational inequalities with strongly indefinite quadratic part. We use a nonsmooth
variational framework. An application to an elliptic system with an obstacle is given
How to sample a linear mechanical system
No full textVariational integrators is a a new discretization technique of the equations of motion of a mechanical system introduced by Veselov and further developed by J. Marsden an co-workers, which is now widely used by numerical analysts working in various applied fields. This discretization technique, unlike the usual discretization procedures familiar in control, e.g. zero-order-hold, can lead to simple and well-conditioned transformation formulas for the recovery of the continuous time parameters from the discretized model.We discuss variational integrators for linear second order mechanical systems and show that physically meaningful properties of the continuous-time model, like passivity, are preserved. Variational integrator discretization is also shown to provide well-conditioned models for the identification of continuous-time second-orders systems starting from measured data
A Virtual Rider for Motorcycles: An Approach Based on Optimal Control and Maneuver Regulation
No full textRecently developed optimization and nonlinear control strategies are applied to drive a multi-body motorcycle model along a specified path with an associated velocity profile. The resulting control scheme is based on three main pillars: a dynamic inversion procedure to compute the input-state trajectories corresponding to a desired maneuvering task, an inverse optimal control heuristic for designing closed loop dynamics, and a maneuver regulation controller to overcome limitations of standard trajectory tracking scheme. The controller (virtual rider) is implemented on a commercial simulation software. Simulation results are presented
Computing Laser Beam Paths in Optical Cavities: An Approach Based on Geometric Newton Method
No full textIn the last decade, increasing attention has been drawn to high-precision optical experiments, which push resolution and accuracy of the measured quantities beyond their current limits. This challenge requires to place optical elements (e.g., mirrors, lenses) and to steer light beams with subnanometer precision. Existing methods for beam direction computing in resonators, e.g., iterative ray tracing or generalized ray transfer matrices, are either computationally expensive or rely on overparameterized models of optical elements. By exploiting Fermat’s principle, we develop a novel method to compute the steady-state beam configurations in resonant optical cavities formed by spherical mirrors, as a function of mirror positions and curvature radii. The proposed procedure is based on the geometric Newton method on matrix manifold, a tool with second-order convergence rate, that relies on a second-order model of the cavity optical length. As we avoid coordinates to parametrize the beam position on mirror surfaces, the computation of the second-order model does not involve the second derivatives of the parametrization. With the help of numerical tests, we show that the convergence properties of our procedure hold for non-planar polygonal cavities, and we assess the effectiveness of the geometric Newton method in determining their configurations with high degree of accuracy and negligible computational effort
A dynamic inversion approach to motorcycle trajectory exploration
No full textRecently developed optimization and nonlinear control
strategies are applied to ride a multi-body motorcycle model
along a specified path with an associated velocity profile. The
resulting control scheme is based on three main pillars: a
dynamic inversion procedure to compute the input-state trajectories
corresponding to a desired maneuvering task, an inverse
optimal control heuristic for designing closed loop dynamics,
and a maneuver regulation controller to overcome limitations of
standard trajectory tracking scheme. The controller (virtual rider)
is implemented on a commercial simulation software. Simulation
results are presented
A imagem de Alessandro Baricco no Brasil
Full text linkDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão, Programa de Pós-Graduação em Estudos da Tradução, Florianópolis, 2013.Com a intenção de delinear o modo pelo qual o escritor italiano Alessandro Baricco se inseriu no sistema literário brasileiro e os caminhos percorridos pelos seus livros traduzidos, esta dissertação dá voz às experiências tradutórias de seus tradutores. A inserção de Bariccono Brasil tem seu início em 1997, através de uma proposição da Profa. Dra. Roberta Barni à editora Iluminuras da tradução de Oceano Mare. A partir daí, outras sete obras foram publicadas no Brasil, sendo três delas traduzidas por Roberta Barni e as outras quatro por quatro tradutores diferentes. De um lado, considera-se o tradutor como figura principal namediação entre culturas, e, de outro, se analisa a realidade desta figuradentro do sistema literário, sua invisibilidade, seus limites e o exercíciode sua profissão. A pesquisa conta, ainda, com críticas e resenhas referentes ao autor italiano publicadas em jornais consagrados no Brasil, considerando estas como parte constituinte da imagem de Baricco refletida em território nacional. Abstract : Intending to delineate the way the Italian writer Alessandro Baricco has been inserted in the Brazilian literary system and the paths his translated books have followed, this thesis gives voice to the translating experiences of his translators. Baricco's insertion in Brazil began in 1997, through a personal project of Dr. Roberta Barni, with her translation of Oceano Mare. Since then, seven other of his works have been published in Brazil, three of which were translated by Roberta Barni and the other four by four different translators. On the one hand,the translator is considered as the main figure in mediation betweencultures and, on the other, this figure's reality is analyzed within theliterary system: its invisibility, its limits and its professional practice. Criticisms and reviews of this Italian author published in well established Brazilian newspapers are also considered, with the understanding that they are part of Baricco's image reflected here
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