Showing papers in "Mechanism and Machine Theory in 1997"

TL;DR: In this article, a 3D O.O.F. parallel mechanism with articulated parallelograms and a peculiar connection with ball joints and prismatic guides has been used to obtain suitable direct kinematics and easy actuation.

TL;DR: In this paper, the forward and inverse kinematics of a 3DOF parallel mechanism for beam aiming applications are derived in closed form, where three actuated arms are attached to a base via revolute joints.

TL;DR: In this paper, the first and second order kinematic analysis of a three-degrees-of-freedom 3-RPS parallel robot mechanism is presented, where the position and orientation parameters of the moving platform are six, however only three of them are independent.

TL;DR: In this approach, Pareto-optimal robust design solution sets are obtained with the aid of design of experiment set-ups, that utilize ANOVA results to quantify relative dominance and significance of design factors.

TL;DR: In this paper, a mathematical model for the tooth geometry of spiral bevel and hypoid gears is developed based on grinding mechanism and machine-tool settings of the Gleason modified roll hypoid grinder.

TL;DR: In this paper, a geometric condition for platform-type, multi-loop, mechanisms and parallel manipulators, containing spherical joints on the platform, whose existence ensures singularity in such mechanisms is presented.

TL;DR: In this paper, a systematic approach is proposed for the enumeration of N-vertex acyclic graphs with N vertices, and the structural synthesis of one-degree-of-freedom (DOF) geared kinematic chains with up to eight links has been successfully constructed.

TL;DR: In this paper, the Hamming number technique was extended to reveal identity and symmetry among the links and joints of a planar kinematic chain without having to test for degeneration and isomorphism.

TL;DR: In this paper, the influence of misalignment on the backlash between the surfaces of the rotor surfaces was investigated with numerical examples. But the authors focused on conjugation of surfaces or rotors, and the synthesis of rotor surfaces with two lines of contact.

TL;DR: Reliability synthesis procedure of spatial linkages is developed to compute optimal assignments of manufacturing tolerances and clearances to individual link dimensions and moving hinges which give the desired mechanism reliability while minimizing the overall cost.

TL;DR: In this paper, a simple and efficient method for optimum kinematic synthesis of multibody systems is presented, based on the use of a set of fully Cartesian coordinates.

TL;DR: An atlas of 64 linkage-type grippers is presented and for each mechanism one of the possible functional schematic is provided for a better understanding of its kinematic properties.

TL;DR: The authors present a dynamic formulation technique for parallel manipulators which result in a parallelism in the dynamic equations of the abovementioned devices which can be effectively utilized to reduce the computational burden of a controller which is equipped with parallel processors.

TL;DR: The Turin parallel robot as discussed by the authors is a parallel manipulator whose mobile platform has 6 DOF and is connected to three double parallelograms via three spherical joints and prismatic slider guides, whose axes are perpendicular to the mechanism planes.

TL;DR: In this article, a dynamical model of the truck crane and the lifted load is presented, in which the flexibility of the support system is taken into account, and the kinematic forcing representing the following controls of truck crane motions are considered.

TL;DR: In this article, the Grubler mobility formula is used to determine linkages which have a connectivity of six between at least two of the links, which are useful in the design of mechanical arms.

TL;DR: In this paper, Rao et al. introduced the concept of symmetry in kinematic chains and its utility in detecting isomorphism among chains, and in rating them, and wrote the Hamming matrix directly to save time and effort, for a chain.

TL;DR: The analytical-form position analysis of one of the three existing 7-link Assur kinematic chains, precisely the one featuring three binary links and four ternary links, results in a 14th order polynomial equation in one unknown whose 14 roots correspond, in the complex domain, to as many assembly configurations.

TL;DR: In this article, the pitch and angle of a closed ruled surface are given in terms of the integral invariants of the dual spherical closed curve corresponding to the closed rule surface under consideration, and the pitch is defined as a function of the angle of pitch.

TL;DR: In this paper, a new approach of a space curve adjoint to a ruled surface is presented, and the geometrical properties of a point trajectory in spatial motion are extensively researched by means of the new adjoint approach.

TL;DR: In this article, the robust design of linkages with minimum sensitivity to variations in dimensions which may be induced by environment, operating conditions, manufacturing defects, aging, deterioration, etc.

TL;DR: In this article, the analytical investigation of an angular shift between a wave generator and a meshing zone of a high torque mechanical harmonic drive has been carried out on the basis of analysis of contact deformations in the system rigid gear/flexible gear/wave generator.

TL;DR: In this paper, the acceleration of an apex seal in the rotor of a Wankel rotary compressor was analyzed and the effects of two cyclic fluctuations in the crankshaft speed during start-up and a simple harmonic fluctuation in the nominal operating speed.

TL;DR: In this article, cubic spline functions are applied to model link deflections and the natural orthogonal complement is used to assemble the constrained dynamical equations of a dynamically balanced four-bar linkage.

TL;DR: In this article, the authors classified the GMMFS problems into direct and inverse kinematics for multi-fingered hand grasping and manipulation, which are peculiar to the fingersurface contact.

TL;DR: In this article, a new flexible rotor beam element is presented to study the dynamic behaviour of manipulators with flexible links and joints, and the coupling terms of link and joint flexibility are considered in the dynamic equations of the manipulator.

TL;DR: In this article, it is shown how it is possible to identify a relevant set of topologies for motion generation, with a perspective on dimensional synthesis, through the direct analytical method based on Burmester theory.

TL;DR: In this article, the authors present an analytical code for dynamic stress analysis and fatigue life prediction of blades based on a combination method, which combines the local strain approach to predict the initiation life and fracture mechanics approach to estimate the propagation life.

TL;DR: In this article, the constrained equations of motion are derived from a minimum principle using a penalty and augmented Lagrangian method, and the sensitivities are evaluated symbolically with the aid of a symbolic manipulator tailored for multibody applications.

TL;DR: In this paper, the dynamics of flexible manipulators are considered and a method is presented for achieving their fast coordinated control using active force control for deformation and disturbance attenuation and PD control for trajectory tracking.