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Brisan C.,Technical University of Cluj Napoca | Vasiu R.-V.,Technical University of Cluj Napoca | Munteanu L.,Institute of Solid Mechanics of Romanian Academy
Transportation Research Part C: Emerging Technologies | Year: 2013

This paper introduces a module-based algorithm for building roads for the virtual environment. The road profiles are developed using road modules designated for driving simulator platforms. These modules developed from mathematical representations of the road geometry are linked together using specific connectivity conditions in accordance with the current road design standards. Such modular approach can be useful to build a low-cost virtual reality environment with an increased degree of realism for driving simulators and higher user flexibility. © 2012 Elsevier Ltd.


Vladareanu L.,Institute of Solid Mechanics of Romanian Academy | Tont G.,University of Oradea | Ion I.,Polytechnic University of Bucharest | Munteanu M.S.,Technical University of Cluj Napoca | Mitroi D.,National University Research Council
Advances in Electrical and Computer Engineering | Year: 2010

The paper presents ZPM dynamic control of walking robots, developing an open architecture real time control multiprocessor system, in view of obtaining new capabilities for walking robots. The complexity of the movement mechanism of a walking robot was taken into account, being a repetitive tilting process with numerous instable movements and which can lead to its turnover on an uneven terrain. The control system architecture for the dynamic robot walking is presented in correlation with the control strategy which contains three main real time control loops: balance robot control using sensorial feedback, walking diagram control with periodic changes depending on the sensorial information during each walk cycle, predictable movement control based on a quick decision from the previous experimental data. The results obtained through simulation and experiments show an increase in mobility, stability in real conditions and obtaining of high performances related to the possibility of moving walking robots on terrains with a configuration as close as possible to real situations, respectively developing new technological capabilities of the walking robot control systems for slope movement and walking by overtaking or going around obstacles. © 2010 AECE.


Baldovin S.,Polytechnic University of Bucharest | Baldovin D.,Institute of Solid Mechanics of Romanian Academy
UPB Scientific Bulletin, Series D: Mechanical Engineering | Year: 2015

The vibration level and the comfort of the vehicles can be improved by replacing its passive suspension by a controlled semi-Active or active suspension. Various semi-Active control algorithms have been suggested in the past, some of them are groundhook strategies. Many of these studies approach systems with more degrees of freedom. In this paper is presented the groundhook control strategy for SDOF dynamical system with harmonic base excitation in comparison with an undamped and linear damped dynamic system. The comparison is made by numerical simulation in Matlab Simulink for two important transfer functions of those dynamic systems. The results show that the semi-Active control for sinusoidal excitation provides better results than the classic suspension.


Cononovici S.B.,Institute of Solid Mechanics of Romanian Academy | Curaj A.,Polytechnic University of Bucharest
Proceedings of the Romanian Academy Series A - Mathematics Physics Technical Sciences Information Science | Year: 2010

Vehicles which operate more or less autonomously are considered belonging to the robot's family. The legged vehicles have the potential advantage to be able to operate over irregular terrain. The planning and control of these robots is considered hierarchically organized on two levels. At the high level, the robot is piloted in the task world. At the local level - operative level - the locomotion function is performed. In this paper, walking orthogonal hexapods, for moving along uneven terrain are the object of study. By kinematic analysis the direct and inverse geometrical models and a differential model are developed. The accommodation to terrain using force sensing is approached too. This approach is useful to write the control algorithms of the analyzed robots or of other structures by analogy.


Sandru O.I.,Polytechnic University of Bucharest | Vladareanu L.,Institute of Solid Mechanics of Romanian Academy | Schiopu P.,Polytechnic University of Bucharest | Vladareanu V.,Polytechnic University of Bucharest | Sandru A.,Polytechnic University of Bucharest
UPB Scientific Bulletin, Series A: Applied Mathematics and Physics | Year: 2013

This paper will "extend" Extenics Theory from the one-dimensional case known at present to the n-dimensional case, n > 1. Due to the importance of this theory in solving multiple practical problems, the extension presented in this paper brings a maximum of technical consistency to the applicative field.


Chiroiu V.,Institute of Solid Mechanics of Romanian Academy | Munteanu L.,National Institute for Aerospace Research Elie Carafoli | Ursu I.,Institute of Solid Mechanics of Romanian Academy
CMES - Computer Modeling in Engineering and Sciences | Year: 2011

Chaotic behavior of uncertain nonlinear systems offers a rich variety of orbits, which can be controlled by bounding the signals involved in closed-loop systems. In this paper, systems with nonlinear uncertainties with no prior knowledge of their bounds, unmodeled dynamic law and rapidly varying disturbances are analyzed in order to propose a stabilization controller of the chaotic behavior via the fuzzy logic systems. © 2011 Tech Science Press.


Chiroiu V.,Institute of Solid Mechanics of Romanian Academy | Munteanu L.,Institute of Solid Mechanics of Romanian Academy | Delsanto P.P.,Polytechnic University of Turin
Computers, Materials and Continua | Year: 2010

Conventional continuum theories are unable to capture the observed indentation size effects, due to the lack of intrinsic length scales that represent the measures of nanostructure in the constitutive relations. In order to overcome this deficiency, the Toupin-Mindlin strain gradient theory of nanoindentation is formulated in this paper and the size dependence of the hardness with respect to the depth and the radius of the indenter for multiple walled carbon nanotubes is investigated. Results show a peculiar size influence on the hardness, which is explained via the shear resistance between the neighboring walls during the buckling of the multiwalled nanotubes. Copyright © 2010 Tech Science Press.


Vladareanu V.,Polytechnic University of Bucharest | Schiopu P.,Polytechnic University of Bucharest | Vladareanu L.,Institute of Solid Mechanics of Romanian Academy
UPB Scientific Bulletin, Series A: Applied Mathematics and Physics | Year: 2014

The paper presents advanced method for solving contradictory problems of hybrid position-force control of the movement of walking robots by applying an "Extension Set". Starting from the extension distance defined by Prof. Cai Wen, the founder of Extenics, there are determined the 2D space dependent function on position and force in relation to standard positive field on position respective on force. The generalization of the extension distance and dependent function using Extenics Multidimensional Theory eliminates the crisp logic matrix of Cantor logic which describes the position-force sequences. Thus was developed an optimization method for hybrid position-force control which ensures positioning precision and robot motion stability on rough terrain.


Munteanu L.,Institute of Solid Mechanics of Romanian Academy | Toader A.,National Institute for Aerospace Research Elie Carafoli
CMES - Computer Modeling in Engineering and Sciences | Year: 2010

The best methods of the genetic algorithms (GA) are obtained in order to optimize the shape of a thin elastic rod subjected to spatial bending and torsion. The optimal cross-section is determined from the minimum volume condition, against the three modal bucklings. Copyright © 2010 Tech Science Press.


Hanawa T.,Tokyo University of Agriculture and Technology | Deng M.,Tokyo University of Agriculture and Technology | Vladareanu L.,Institute of Solid Mechanics of Romanian Academy
International Conference on Advanced Mechatronic Systems, ICAMechS | Year: 2013

In this paper, a operator-based robust nonlinear control system for nonlinear plants with uncertain backlash is proposed by using power integrator. Firstly, a backlash model including uncertainties in its threshold is proposed. Secondly, a robust nonlinear control system is designed by using power integrator. Finally, the effectiveness of the proposed control system is confirmed by simulations. © 2013 IEEE.

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