Showing papers in "Mechanism and Machine Theory in 1990"

TL;DR: The direct position analysis of the Stewart platform mechanism, that is to find position and orientation of the platform when a set of actuator displacements is given, has been performed in closed-form and leads to a 16th order polynomial equation in one unknown from which 16 different positions and orientations of theplatform can be derived.

TL;DR: The final product of the program is the solution concept, a functional schematic of the product/process showing a pictorial view of its parts which are drawn from the solutions data base.

TL;DR: In this paper, the authors present all possible linear combinations of given instantaneous screws in projective five-space, and prove that screw systems can be expressed in terms of lines and screws.

TL;DR: In this paper, a methodology for concurrent product and process design and a computational framework that supports it is described, based on the premise that manufacturability is best assured by simultaneously designing a part or assembly and the process used to fabricate it.

TL;DR: The kinematic relationships among tolerance, drive parameters and performance indices are analytically defined, and subsequently analyzed in detail via a computer-aided procedure, and two simple and practical formulas for design synthesis of cycloid drives are developed.

TL;DR: In this paper, the authors apply and extend the material of Part 1 (Mech. Mach. Theory25, 1−10; 1990), systematically studying all the screw systems in the screw space, corresponding to motions of one, two and three freedoms.

TL;DR: In this paper, the authors present a method by which the imprecision and uncertainty in the description of the design's components can be represented using Fuzzy set theory. But this method is not suitable for machine design.

TL;DR: In this article, a method of selecting nonisomorphic graphs with the aid of graph enumeration theory is introduced, where edge permutations which are induced from the symmetric group of vertex permutations are used as mapping functions.

TL;DR: The Monte Carlo method is used to determine the volume of the workspace of manipulators, the accessibility of the workspaces, and the effect of changes in the geometric parameters on the workspace volume.

TL;DR: In this paper, a novel method of active balancing designed to eliminate completely the shaking moment, the driving torque or both simultaneously is described. But the method is based on simple general principles equally applicable for any planar mechanism.

TL;DR: In this paper, a variable-separation technique, consisting of decoupling the configuration variables from the linkage parameters, is applied in the optimization of planar linkages for rigid-body guidance.

TL;DR: In this paper, the authors present design equations and techniques for the complete shaking force and shaking moment balancing of 26 types of four-five-and six-bar linkages with prismatic pairs due to both linear and rotary inertia, but external loads, by using the method which is a combination of mass redistribution and the addition of two kinds of the inertia counterweights.

TL;DR: In this paper, the kinematics of the crane telescopic boom is studied for all possible movements produced by its controls, and the initial problem obtained has been solved using the Runge-Kutta method of the fourth order.

TL;DR: In this paper, the authors describe a theory of design from an optimization perspective, covering a broad spectrum of the design cycle: from qualitative and innovative design to global numerical parametric design.

TL;DR: The development of the representation scheme and reasoning procedures are illustrated with simple examples from machine design and procedures to support design verification, design selection and design synthesis using algebraic and logical transformation rules are presented.

TL;DR: In this article, a special function is proposed for adding to the control algorithm to make full use of the joint availability, and a joint parameter arrangement of joint parameters to minimize the incidence of singularities is presented.

TL;DR: In this article, an analytical method based on a Lagrangian formulation is presented to model the dynamics of spatial, multi-link, open-loop mechanisms such as manipulators.

TL;DR: In this article, a dual integral invariant has been defined for a given closed ruled surface in R 3 and holditch and Steiner theorems in the plane kinematics have been generalized to the line space.

TL;DR: The notion of designing for concept is introduced and it is shown how it could apply to the designs of linkages and the word form of an integrated compromise DSP is presented that makes provision for simultaneous kinematic and dynamic synthesis of four-bar linkages.

TL;DR: In this article, the determination of pinion cutter offsets to generate nonstandard spur gears to satisfy the design constraint of maximum recess to approach action or equalizing the tooth strengths for a pinion and gear set requires the solution of four simultaneous design constraints.

TL;DR: In this paper, a numerical technique is developed for determining the individual hob offsets for a pair of spur gears designed to operate at a nonstandard center distance with the maximum ratio of recess to approach action or to balance tooth strengths of the pinion and gear.

TL;DR: In this paper, a general method for complete shaking moment balancing of linkages by a prescribed input speed fluctuation is developed, which is applicable for any planar mechanism, and the prescribed motion depends on the specified coefficient of fluctuation and the latter could be appropriately reduced if input link with higher moment of inertia is used.

TL;DR: In this paper, a hydraulic actuator to be included in a general purpose finite element program for mechanism analysis is presented, where the element takes into consideration all nonlinear effects to calculate the response, including Coulomb friction, variation of fluid properties with pressure and variation of certain geometrical characteristics with the elongation.

TL;DR: In this article, a simple form of expression for writing down a screw which has undergone a transformation of reference frame is established, and simplifications to the standard problems of identifying the principal axes of a screw system and identifying the axis line of a finite twisting motion are demonstrated.

TL;DR: In this article, the primary mechanical and control parameters of robots are usually determined for design purposes by reference to theories of linear and continuous systems, which provide a simple and attractive engineering approach.

TL;DR: In this article, the system of n cooperating robots, handling an object in such a way that there is no relative motion among grippers of manipulators and the object, is considered.

TL;DR: A design tree structure is proposed for the optimization of mechanisms which considers both geometric and topological change to move away from the rigid structure imposed by conventional nonlinear programming and to allow “real” design issues to be addressed.

TL;DR: In this article, an adaptive motion controller for rigid robot manipulators is presented, which consists of a computed torque plus compensation control law and an integral adaptive law, and global tracking convergence is shown.

TL;DR: In this article, nonlinear programming techniques are applied to the optimum design of systems consisting of a four-bar linkage driven by a disk cam, where the primary design objective is the minimization of input torque fluctuation under the assumed condition of constant input angular velocity of the cam.

TL;DR: In this work the critical speed ranges for an elastic mechanism are determined using independent general methods that are capable of analyzing mechanism systems with all members being elastic and of complex shape.