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Acceleration Analysis of 3-RPS Parallel Manipulators by Means of Screw Theory InTech
J. Gallardo; H. Orozco; J.M. Rico; C.R. Aguilar; L. Perez.
In this work the kinematics, including the acceleration analysis, of 3-RPS parallel manipulators has been successfully approached by means of screw theory. Firstly, the forward position analysis was carried out using recursively the Sylvester dialytic elimination method, such a procedure yields a 16-th polynomial expression in one unknown, and therefore all the possible solutions of this initial analysis are systematically calculated. Afterwards, the velocity and acceleration analyses are addressed using screw theory. To this end, the velocity and reduced acceleration states of the moving platform, with respect to the fixed platform are written in screw form through each one of the three limbs of the manipulator. Simple and compact expressions were derived...
Tipo: 16 Palavras-chave: Parallel Manipulators; New Developments.
Ano: 2008 URL: http://www.intechopen.com/articles/show/title/acceleration_analysis_of_3-rps_parallel_manipulators_by_means_of_screw_theory
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Application of Neural Networks to Modeling and Control of Parallel Manipulators InTech
Ahmet Akbas.
This chapter is mainly concerned with the application of ANNs to modeling and control of parallel manipulators. A practical implementation is completed to emulate the operation of
Tipo: 2 Palavras-chave: Parallel Manipulators; New Developments.
Ano: 2008 URL: http://www.intechopen.com/articles/show/title/application_of_neural_networks_to_modeling_and_control_of_parallel_manipulators
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Asymptotic Motions of Three-Parametric Robot Manipulators with Parallel Rotational Axes InTech
Jan Baksa.
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Tipo: 3 Palavras-chave: Parallel Manipulators; New Developments.
Ano: 2008 URL: http://www.intechopen.com/articles/show/title/asymptotic_motions_of_three-parametric_robot_manipulators_with_parallel_rotational_axes
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Calibration of 3-DOF Translational Parallel Manipulators Using Leg Observations InTech
Anatol Pashkevich; Damien Chablat; Philippe Wenger; Roman Gomolitsky.
Recent advances in parallel robot architectures encourage related research on kinematic calibration of parallel mechanisms. This paper proposes a novel calibration approach based on observations of manipulator leg parallelism with respect to the Cartesian planes. Presented for the Orthoglide-type mechanisms, this approach may be also applied to other manipulator architectures that admit parallel leg motions (along the Cartesian axes) or, in more general case, allow locating the leg in several postures with a common intersection point. The proposed calibration technique employs a simple and low-cost measuring system composed of standard comparator indicators attached to the universal magnetic stands. They are sequentially used for measuring the deviation of...
Tipo: 11 Palavras-chave: Parallel Manipulators; New Developments.
Ano: 2008 URL: http://www.intechopen.com/articles/show/title/calibration_of_3-dof_translational_parallel_manipulators_using_leg_observations
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Conserving Integrators for Parallel Manipulators InTech
Stefan Uhlar; Peter Betsch.
We have shown that the proposed rotationless formulation of multibody dynamics is wellsuited for the energymomentum conserving integration of both open-loop and closed-loop multibody systems. Although the use of rotations has been completely circumvented throughout the whole discretization, joint-forces can still be applied to a specific multibody system by resorting to the proposed coordinate augmentation technique. The present developments have been restricted to the planar case. However, it is important to note, that the extension to the three-dimensional setting can be performed without any conceptual differences. Similarly, alternative types of joints belonging to the class of lower kinematic pairs such as cylindric joints can be easily incorporated...
Tipo: 5 Palavras-chave: Parallel Manipulators; New Developments.
Ano: 2008 URL: http://www.intechopen.com/articles/show/title/conserving_integrators_for_parallel_manipulators
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Control of a Flexible Manipulator with Noncollocated Feedback: Time Domain Passivity Approach InTech
Jee-Hwan Ryu; Dong-Soo Kwon; Blake Hannaford.
In this paper, we propose a stability guaranteed control scheme of noncollocated feedback control systems without any model information. The main contribution of this research is proposing a method to implement the PO/PC for a possibility active plant due to the noncollocated feedback. We separate the active plant into passive one and a transfer function from the collocated output to the noncollocated output. Therefore, the control system can be fit to our PO/PC framework. As a result, we can achieve stable control even for the noncollocated control system.
Tipo: 20 Palavras-chave: Parallel Manipulators; New Developments.
Ano: 2008 URL: http://www.intechopen.com/articles/show/title/control_of_a_flexible_manipulator_with_noncollocated_feedback__time_domain_passivity_approach
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Design, Analysis and Applications of a Class of New 3-DOF Translational Parallel Manipulators InTech
Yangmin Li; Qingsong Xu.
In this chapter, a new class of translational parallel manipulator with 3-PCR architecture has been proposed. It has been shown that such a mechanism can act as an overconstrained 3DOF translational manipulator with some certain assembling conditions satisfied. Since the
Tipo: 24 Palavras-chave: Parallel Manipulators; New Developments.
Ano: 2008 URL: http://www.intechopen.com/articles/show/title/design__analysis_and_applications_of_a_class_of_new_3-dof_translational_parallel_manipulators
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Design and Prototyping of a Spherical Parallel Machine Based on 3-CPU Kinematics InTech
Massimo Callegari.
The article has described an innovative spherical parallel wrist developed at the Polytechnic University of Marche in Ancona, revisiting all the main design steps, from kinematic synthesis up to physical prototyping. Machine kinematics has been worked out in closed form and all the singularity surfaces have been analysed: it has been pointed out that the mechanism does not possess inverse kinematics singularities, while direct kinematics singularities and translation singularities lie on the same closed surface. The inner space, where motion paths can be safely planned, has been identified and unfortunately it cannot be enlarged by kinematics optimisation because machine's Jacobian does not depend on geometrical parameters. For this reason, it was decided...
Tipo: 9 Palavras-chave: Parallel Manipulators; New Developments.
Ano: 2008 URL: http://www.intechopen.com/articles/show/title/design_and_prototyping_of_a_spherical_parallel_machine_based_on_3-cpu_kinematics
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Dynamic Modelling and Vibration Control of a Planar Parallel Manipulator with Structurally Flexible Linkages InTech
Bongsoo Kang; James K. Mills.
In this chapter, the equations of motion for the planar parallel manipulator are formulated by applying the Lagrangian equation of the first type. Introducing Lagrangian multipliers simplifies the complexities due to multiple closed loop chains of the parallel mechanism and the structurally flexible linkages. An active damping approach applied to two different piezoelectric materials, which are used as actuators to damp unwanted vibrations of flexible
Tipo: 21 Palavras-chave: Parallel Manipulators; New Developments.
Ano: 2008 URL: http://www.intechopen.com/articles/show/title/dynamic_modelling_and_vibration_control_of_a_planar_parallel_manipulator_with_structurally_flexible_
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Error Modeling and Accuracy of TAU Robot InTech
Hongliang Cui; Zhenqi Zhu; Zhongxue Gan; Torgny Brogardh.
It can be observed from the results, that Jacobian Matrix is effective with an accuracy up to 1.53 um with an input error of 1 mm (Link 1 of lower arm 1). This was verified using ADAMS simulation results. Results from N-R method match very well with ADAMS simulation with a difference of only 0.06 um. Based on the D-H model and an accurate Jacobian matrix, a series of results have been presented including error analysis, forward kinematic, redundant variable determination, error budget, and Jacobian approximation method. The Jacobian approximation method can be used in on-line control of the robot. For the TAU robot, a closed form solution of a forward kinematic problem is reached with a high accuracy instead of N-R numerical solution. The simulation...
Tipo: 13 Palavras-chave: Parallel Manipulators; New Developments.
Ano: 2008 URL: http://www.intechopen.com/articles/show/title/error_modeling_and_accuracy_of_tau_robot
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Kinematic Parameters Auto-Calibration of Redundant Planar 2-DOF Parallel Manipulator InTech
Shuang Cong; Chunshi Feng; Yaoxin Zhang; Zexiang Li; Shilon Jiang.
In this chapter, we implemented the kinematic auto-calibration of a redundant planar 2-dof parallel manipulator. In this process, we first calibrated the error of the sensor zero positions by optimizing an projected tracking error function, and also the robustness of this method has been proved. Furthermore, in order to calibrate the other parameters of this parallel manipulator, we gave another error function based on the closed-loop constraint equations. By decoupling the product items in the error function, we simplified the optimization and more precise result was obtained. But, at most 11 out 12 parameters could be calibrated using only local optimization method. In order to calibrate all of the parameters, global optimization methods including GA,...
Tipo: 12 Palavras-chave: Parallel Manipulators; New Developments.
Ano: 2008 URL: http://www.intechopen.com/articles/show/title/kinematic_parameters_auto-calibration_of_redundant_planar_2-dof_parallel_manipulator
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Multiscale Manipulations with Multiple Parallel Mechanism Manipulators InTech
Gilgueng Hwang; Hideki Hashimoto.
We have shown a dexterous micromanipulation system based on single-master and multislave device configuration and its deformable object micromanipulation such as styrene block and roe. The system enables 6 d.o.f. object position control using 2 parallel mechanism micromanipulators. It has potential applications for manipulating, characterization, complicated device assembly, and biological cell manipulation. In addition to the
Tipo: 17 Palavras-chave: Parallel Manipulators; New Developments.
Ano: 2008 URL: http://www.intechopen.com/articles/show/title/multiscale_manipulations_with_multiple_parallel_mechanism_manipulators
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Neural Network Solutions for Forward Kinematics Problem of HEXA Parallel Robot InTech
M. Dehghani; M. Eghtesad; A. A. Safavi; A. Khayatian; M. Ahmadi.
In this chapter, we proposed to use neural networks for FK solution of HEXA robot, which can be elaborated to generate the best estimation of forward kinematics of the robot. The research results in this chapter are quite important as they solve a problem for which there is no known closed form solution. Besides, the presented solution in this research has the better prediction and obtains smaller error in compare to the other works which have studied FKP of HEXA robot to the best of our knowledge.
Tipo: 15 Palavras-chave: Parallel Manipulators; New Developments.
Ano: 2008 URL: http://www.intechopen.com/articles/show/title/neural_network_solutions_for_forward_kinematics_problem_of_hexa_parallel_robot
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On the Robust Dynamics Identification of Parallel Manipulators: Methodology and Experiments InTech
Houssem Abdellatif; Bodo Heimann; Jens Kotlarski.
The present chapter discussed most significant aspects to achieve accurate and robust dynamics identification for parallel manipulators with 6 dof's. Hereby, the adequate consideration of structural properties of such systems has been stressed out. First, an efficient methodology to determine the inverse dynamics in a parameterlinear form has been presented, which enables the use of linear estimation techniques. Periodic excitation has been proved to be a powerful method for parallel robots, since it allows for appropriate consideration of hard workspace constraints. Due to measurement noise and cross coupling between the actuators, the achievement of the identification in a statistical framework is recommended. This includes the consideration of...
Tipo: 1 Palavras-chave: Parallel Manipulators; New Developments.
Ano: 2008 URL: http://www.intechopen.com/articles/show/title/on_the_robust_dynamics_identification_of_parallel_manipulators__methodology_and_experiments
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Parallel Robot Scheduling with Genetic Algorithms InTech
Tarik Cakar; Harun Resit Yazgan; Rasit Koker.
The genetic algorithms (GA) have the great advantage and success in the solution of NP problems. There are various important applications on this way. In this study, the job with n-number of precedence constraints is assigned minimizing total earliness and tardiness and maximum flow time on m-number of parallel machine. Genetic algorithms and simulated annealing methods were used to find the solutions, which minimizes the total earliness and tardiness costs. In GA, the solution alternatives, which were obtained by using genetic operators, were investigated to understand that if they are feasible or not and the feasible ones according to precedence constraints were considered. The way, trying to make infeasible solutions feasible, was not selected....
Tipo: 8 Palavras-chave: Parallel Manipulators; New Developments.
Ano: 2008 URL: http://www.intechopen.com/articles/show/title/parallel_robot_scheduling_with_genetic_algorithms
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Principal Screws and Full-Scale Feasible Instantaneous Motions of Some 3-DOF Parallel Manipulators InTech
Z. Huang; J. Wang; S. H. Li.
This chapter presents a study on the full-scale instant twists motions of 3-DOF parallel manipulators. The study is of extremely benefit to understand and correctly apply a mechanism. It is based on principal screws of the screw system. The key problem is to derive three principal screws from a given 3-DOF mechanism. It needs to set the relation between the pitches of the principal screws and the three linear inputs of the mechanism. In this chapter, the effective method to identify the principal screws of a third-order screw system of 3-DOF mechanisms is presented. For obtaining the principal screws there introduce two methods, the quadratic curve degenerating theory and quadric degenerating theory. Besides, the imaginary-mechanism influence coefficient...
Tipo: 18 Palavras-chave: Parallel Manipulators; New Developments.
Ano: 2008 URL: http://www.intechopen.com/articles/show/title/principal_screws_and_full-scale_feasible_instantaneous_motions_of_some_3-dof_parallel_manipulators
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Quantitative Dexterous Workspace Comparison of Serial and Parallel Planar Mechanisms InTech
Geoff T. Pond; Juan A. Carretero.
Through either method of obtaining a constrained dimensionally homogeneous Jacobian matrix (proposed by (Gosselin, 1992) or by (Pond & Carretero, 2006)) for planar mechanisms, a choice exists on which of the potential six Cartesian velocity components on the end effector be used to define the task space velocity variables. The choice has an influence on the resulting Jacobian matrix and therefore its condition number and singular values. Without constraining the Jacobian matrix, the condition number was demonstrated to be essentially meaningless, as in (Kim & Ryu, 2003). In terms of measuring dexterity, the constrained dimensionally homogeneous Jacobian matrices (J'P) are superior to the screw based Jacobian matrix (J) in that they are...
Tipo: 10 Palavras-chave: Parallel Manipulators; New Developments.
Ano: 2008 URL: http://www.intechopen.com/articles/show/title/quantitative_dexterous_workspace_comparison_of_serial_and_parallel_planar_mechanisms
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Singularity Robust Inverse Dynamics of Parallel Manipulators InTech
S. Kemal Ider.
A general method for the inverse dynamic solution of parallel manipulators in the presence of drive singularities is developed. It is shown that at the drive singularities, the actuator forces cannot influence the end-effector accelerations instantaneously in certain directions. Hence the end-effector trajectory should be chosen to satisfy the consistency of the dynamic
Tipo: 19 Palavras-chave: Parallel Manipulators; New Developments.
Ano: 2008 URL: http://www.intechopen.com/articles/show/title/singularity_robust_inverse_dynamics_of_parallel_manipulators
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Specific Parameters of the Perturbation Profile Differentially Influence the Vertical and Horizontal Head Accelerations During Human Whiplash Testing InTech
Loriann M. Hynes; Natalie S. Sacher; James P. Dickey.
This study directly compared two different perturbation profiles, using repeated measures, to evaluate vertical and horizontal head accelerations during whiplash-like perturbations. We observed that the magnitude of the vertical head accelerations depended on the specific perturbation parameters; the horizontal and vertical acceleration magnitudes were not significantly different in the mild perturbation, but the horizontal head accelerations were significantly larger than the vertical accelerations during the moderate perturbations. These findings illustrate that human subjects have different responses to whiplash-like perturbations depending on the specific acceleration profile parameters, including peak acceleration. This finding is in contrast to one...
Tipo: 14 Palavras-chave: Parallel Manipulators; New Developments.
Ano: 2008 URL: http://www.intechopen.com/articles/show/title/specific_parameters_of_the_perturbation_profile_differentially_influence_the_vertical_and_horizontal
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Tactile Displays with Parallel Mechanism InTech
Ki-Uk Kyung; Dong-Soo Kwon.
This chapter deals with tactile displays and their mechanisms. We briefly reviewed research history of mechanical type tactile displays and their parallel arrangement. And this chapter mainly describes two systems including tactile displays. The 5x6 pin arrayed tactile display with parallel arrangement of piezoelectric bimorphs has been described in the section 3. The tactile display has been embedded into a mouse device and the performance of the device has been verified from pattern display experiment. Another focus of this chapter is describing a compact tactile display module and verifying its performance in a pen-like form factor. As described in section 4, a small, safe, low power consuming, silent and light tactile display module with parallel and...
Tipo: 23 Palavras-chave: Parallel Manipulators; New Developments.
Ano: 2008 URL: http://www.intechopen.com/articles/show/title/tactile_displays_with_parallel_mechanism
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