Showing papers in "Mechanism and Machine Theory in 2006"

TL;DR: A survey of the literature related to dynamic analyses of flexible robotic manipulators has been carried out in this article, where both link and joint flexibility are considered in this work and an effort has been made to critically examine the methods used in these analyses, their advantages and shortcomings and possible extension of these methods to be applied to a general class of problems.

TL;DR: In this paper, a methodology for the dynamical analysis of mechanical systems considering realistic joint characteristics, namely, joints with clearance and lubrication, is presented, in which the energy dissipation in form of hysteresis damping is considered.

TL;DR: In this paper, the design, manufacturing, stress analysis, and results of experimental tests of spiral bevel gears with low levels of noise and vibration and increased endurance have been discussed, where the main goals are the improvement of the bearing contact, the achievement of a predesigned parabolic function of transmission errors, reduction of the magnitude of transmission error, and avoidance of areas of severe contact stresses for the increase of the gear drive endurance.

TL;DR: In this article, a general approach is proposed to check the force-closure condition of a cable-driven parallel mechanism (CDPM), which is expressed in terms of the convex hull which encloses the origin.

TL;DR: In this paper, a non-dimensional design space is established to investigate the singular loci and workspace shape of the 5R symmetrical parallel mechanisms, systematically, and the atlas of the maximal inscribed workspace (MIW) radius is presented.

TL;DR: In this paper, a model for the simulation of the three-dimensional dynamic behaviour of planetary/epicyclic spur and helical gears is presented, which enables simulation of 3D dynamic behavior of ring-gears.

TL;DR: In this paper, the optimal design of the planar 5R symmetrical parallel mechanism with respect to the atlases is discussed in the established design space, where the optimal non-dimensional result obtained from the atlas is used to synthesize the link lengths of the studied mechanism with specified criteria.

TL;DR: The condition number of the Jacobian matrix has been commonly used in determining the dexterous regions of a manipulator workspace as discussed by the authors, however, for manipulators having a mix of both rotational and translational degrees of freedom, the condition number may not be used due to dimensional inconsistencies with its elements.

TL;DR: In this paper, a closed-loop flexible-link model is proposed and applied to a planar parallel platform developed in a laboratory. Butler et al. used the Lagrange finite element (FE) formulation to model flexible linkages, in which both translational and rotary degrees of freedom exist.

TL;DR: In this paper, a method of calculating the deformation characteristics of roller slewing bearings is presented, where the type and the parameters of the roller generator correction have the largest influence on the analysed deformation.

TL;DR: The development of the finite twist has attracted much attention in the field of theoretical kinematics and the proposed q-pitch with the tangent of half the rotation angle has demonstrated an elegant use in the study of rigid body displacements as discussed by the authors.

TL;DR: The imitation of walking gait pattern by the proposed prosthesis was provided with a trajectory control scheme for the knee joint angle in accordance with the necessity of rule-based control approach.

TL;DR: In this paper, a simple and exact approach for the lobe profile design of the cycloid plate gear, which is a main part of cycloid reducer, by means of the principle of the instant velocity center in the general contact mechanism and the homogeneous coordinate transformation is proposed.

TL;DR: In this paper, it is shown that the singular value decomposition is not needed to derive the approximation error, the polar decomposition of the homogeneous transformation matrix being sufficient, and that the approximation does not have a minimum that would allow us to define naturally the characteristic length.

TL;DR: In this article, a model for investigating structural vibrations in rolling element bearings due to radial internal clearance is presented, where the contacts between rollers and races are treated as nonlinear springs and the springs act only in compression.

TL;DR: In this paper, the authors presented a concept of epicyclical gear train able to generate a variable gear ratio law, which is useful when the synthesis of a specific torque curve or the design of a function generator involve a highly variable input/output relationship.

TL;DR: In this article, the kinematics, statics and dynamics of a planar two-degree-of-freedom tensegrity mechanism are studied, and the stiffness of the mechanism is detailed for different situations.

TL;DR: Based on the Lie-group-algebraic properties of the displacement set, the 3-dof generators of planar gliding motion (G) are introduced in this paper, where a total of 21 mechanical generators of G-G motion with distinct architectures are synthesized systematically.

TL;DR: In this paper, the kinematics and singularity analysis of a four degrees of freedom parallel manipulator are investigated using the theory of screws, and simple and compact expressions are derived for the velocity and reduced acceleration states of the moving platform w.r.t.

TL;DR: In this paper, the authors propose a design approach utilizing a performance chart, which has been applied to most industrial designs, to identify an optimum region, which represents a domain of the normalized parameters, with respect to specified indices.

TL;DR: The main characteristic of the proposed approach is that the type synthesis of legs for SP-equivalent parallel kinematic chains is reduced to thetype synthesis of 4-DOF single-loop kinematics chains and thus easy to perform.

TL;DR: In this article, the authors present a theoretical and experimental study of how interval arithmetic and analysis methods can be used to achieve numerical certification of the kinematic calibration of parallel robots, and a possible validation of the Kinematic model used in calibration.

TL;DR: A different approach for analyzing singularities of parallel robots is presented, based on inspecting the actuators’ line dependencies by use of a matrix called the superbracket, which is similar to the Jacobian matrix and contains Plucker coordinates in its columns.

TL;DR: In this article, a new procedure is introduced to determine maximal singularity-free zones of the 3-RPR parallel mechanisms, which does not involve a discretization of the workspace and the zones obtained are guaranteed to be free from singularities.

TL;DR: In this paper, a robotic die polishing station controlled by a PC and a robot controller is presented, where the path data for the robot end-effector is generated automatically from the NC data of a previous die or mold machining process.

TL;DR: An integrated computational intelligence approach is proposed for dealing with product concept generation and evaluation and the applicability of the proposed method is illustrated with an engineering example.

TL;DR: In this paper, the dimensional design of a finger driving mechanism has been formulated as a multi-objective optimization problem by using evaluation criteria for fundamental characteristics associated with finger motion, grasping equilibrium, and force transmission.

TL;DR: Very efficient algorithms, using group theoretic techniques, exist for exhaustive isomorph-free generation of certain classes of combinatorial objects, which either eliminate or restrict the explicit isomorphism detection as discussed by the authors.

TL;DR: In this article, an evolutionary approach based on a real-coded genetic algorithm is used to obtain the solution of the multimodal inverse kinematics problem of industrial robots, which can be displayed using a 3D modeler developed in MATLAB for the purpose of visualization.

TL;DR: In this article, a control strategy for a two-link manipulator with revolute joints with an unactuated second joint is presented, where the motion of the system is confined to a horizontal plane.