Showing papers on "Kinematics published in 1972"
TL;DR: In this paper, linear programming formulations and solutions are presented for all 10 problem types of the simple plastic theory: analysis under proportional and shakedown loading by kinematic or static approaches; design under fixed, alternative and shake-down loading under kinematics or static approach.
Abstract: Linear programming formulations and solutions are presented for all 10 problem types of the simple plastic theory: analysis under proportional and shake-down loading by kinematic or static approaches; design under fixed, alternative and shake-down loading by kinematic or static approaches. Unavailable LP solutions for the analysis and design of plastic structures under shake-down loading are provided. The application of the computing technique for each type of problem is illustrated on a fairly complex plane frame.
57 citations
TL;DR: In this paper, the kinematic wave equations are used to describe the unsteady flow in a cascade of n discrete overland flow planes or channel segments, and properties of the solutions for a cascade with pulsed lateral inputs are examined.
44 citations
TL;DR: In this paper, the minimum weight design of both perfectly plastic and elastic grillages of given strength as well as elastic grillage of given stiffness and fibre-reinforced plates with given strength is considered.
35 citations
TL;DR: In this article, the authors proposed a technique for the analysis of free surface motions with fixed boundaries and up to three free surfaces, which can solve two-dimensional rectangular or axisymmetric problems.
Abstract: Pressure and acceleration-induced distortion of an incompressible, inviscid liquid region is predicted numerically. The liquid is bounded by both fixed and free boundaries, and its motion is irrotational. Normal velocity is prescribed on fixed, though perhaps permeable boundaries, and the starting velocity potential is given on all free surfaces. Distortions of the liquid region are described by the motion of discrete kinematic markers assigned to each free surface. Problems are formulated on a square mesh computation field in terms of velocity potential. The liquid region interior is solved numerically by overrelaxation at every time step, which permits velocity components and potential rates to be calculated at the free surfaces. Marker positions and potentials are advanced each time step, thus preparing the computation field for further overrelaxation, and the process is repeated until finished. This technique was formulated as a Fortran IV computer program, FREESURF, for studying free surface motions. The technique can solve two-dimension rectangular or axisymmetric problems with fixed boundaries and up to three free surfaces. Bubble expansion and collapse near a free surface, dam break flows, draining of a tank, and other similar problems can be predicted with the method.
19 citations
CERN1
TL;DR: In this paper, the mechanism of kinematic coupling between momentum transfers in producing a low mass two particle system with double-peripheral dynamics is studied theoretically and model calculations.
18 citations
TL;DR: In this article, a scheme for kinematic estimate of the vertical p-velocity ω is designed under the presumption that the profiles should converge to a near zero value at the top of the atmosphere without being so required when a sensitive balance between the analysis scheme and data disposition is achieved.
Abstract: A scheme for kinematic estimate of the vertical p-velocity ω is designed under the presumption that the profiles should converge to a near zero value at the top of the atmosphere without being so required when a sensitive balance between the analysis scheme and data disposition is achieved. The scheme provides a range of eight degrees of optimization in estimating the divergence through the order of polynomial representation of the wind field, the treatment of missing wind data, and the space smoothing of the divergence.
The scheme is applied to synoptic wind observations from the upper-air network over North America. The computed ω profiles and patterns of vertical motion field obtained from those profiles appear to support the proposition. It is indicated that the field of kinematic ω so computed through the depth of atmosphere will be useful in the study of large-scale atmospheric dynamics.
16 citations
TL;DR: In this article, a new theory is proposed which shows that averages have a quasi-kinematic form with parameters different from those of the true kinematic theory, and second order averaging schemes are proposed whereby more information can be extracted from experiments.
Abstract: Averaged LEED spectra can be fitted with good accuracy by a curve of kinematic form. However, theoretical arguments show that a true kinematic average is impossible. The paradox is resolved by a new theory which shows that averages have a quasi-kinematic form with parameters different from those of the true kinematic theory. Some of the new parameters can be simply related to old ones, but others involve complicated corrections. Finally second order averaging schemes are proposed whereby more information can be extracted from experiments.
13 citations
23 Nov 1972
TL;DR: A detective story index as mentioned in this paper is a collection of short stories with possible impossibilities based on a set of possible endings, contexts, content, and possible possibilities of a story.
Abstract: Introduction 1. Selecting a beginning 2. Selecting the possibilities 3. Selection by context 4. Selection by content 5. Selection of content 6. Possible impossibilities 7. A detective story Index.
10 citations
TL;DR: In this article, a number of models of a force field defined by the expansion of the matrix of kinematic coefficients into multipliers are discussed, and relations in which sets of force constants corresponding to these models are transferable to isotopic molecules are given.
10 citations
TL;DR: The procedure is based on the fact that a constant-distance equation is formulated, wherever the distance between two pair-centers of a rigid link remains constant throughout its motion, resulting in a much simpler kinematic analysis of the linkage.
Abstract: The concept and use of constant-distance equations for the kinematic analysis of linkages are presented. The procedure is based on the fact that a constant-distance equation is formulated, wherever...
6 citations
Journal Article•
TL;DR: It is shown that the method is particularly suitable for the analysis of gear trains with more than two degrees of freedom, such as those which are used in many automatic transmissions.
01 Jan 1972
TL;DR: In this article, the relative position equations for the Rancho arm were developed using the Denavit Hartenberg representation and problems introduced by the mechanical structure of the arm and adoption of rate control were described.
Abstract: The relative position equations for the Rancho arm are developed using the Denavit-Hartenberg representation. Equations for coordinated rate control of the wrist are derived and problems introduced by the mechanical structure of the arm and adoption of rate control are described. These problems include:
1.
Nonuniqueness of the rate control equations caused by an extra degree-of-freedom in the mechanical structure.
2.
Transformation singularities caused by arm position.
3.
Loss of coordinated motion when arm joints reach a mechanical limit.
4.
Loss of coordinated motion due to velocity saturation of one or more joints.
TL;DR: In this article, the relativistic kinematics of a three body reaction with the target particle at rest in the laboratory frame are investigated. And the most important kinematic relations involved in a three-body reaction are reported in the appendix.
07 Mar 1972
TL;DR: The fact that so much useful design data can be obtained so readily with the aid of KINSYN indicates that it could be a significant aid in a physiological limb development program.
Abstract: KINSYN is an interactive general purpose computer system for the kinematic synthesis and analysis of mechanisms. It is applicable to kinematics problems ranging from the synthesis of spacecraft antenna deployment mechanisms to the design of folding high chairs. Features of KINSYN have been described in several recent publications.The results shown in this paper were obtained during the first two or three trial runs on KINSYN. Of course, extensive work would remain to be done in order to apply these techniques to a practical artificial limb design, Nonetheless, the fact that so much useful design data can be obtained so readily with the aid of KINSYN indicates that it could be a significant aid in a physiological limb development program.
TL;DR: In this paper, the essential kinematic properties of the path of the inertia pole depending on the center-of-mass trajectory are developed in a simple and modern manner, and an analytical method is also presented for the plane motion having two degrees of freedom, and the spatial motion with one degree of freedom.
TL;DR: In this article, an analysis is presented which proves the feasibility of a chain drive in which the driving and jockey wheels are eccentric and the driven wheel is concentric, the axes of rotation of all three wheels being fixed.
01 Jan 1972
TL;DR: In this article, a three-dimensional analytical model was developed utilizing a technique which describes a holonomic dynamical system by using superfluous coordinates, solving the resulting equations of motion simultaneously with kinematic restraints which maintained both hands of the driver on the steering wheel, the involuntary response was determined for any possible vehicular acceleration.
Abstract: It has been established in this work that sudden and unexpected accelerations of an automobile cause the driver to involuntarily turn the steering wheel In order to study this phenomenon, a three-dimensional analytical model was developed utilizing a technique which describes a holonomic dynamical system by using superfluous coordinates Solving the resulting equations of motion simultaneously with kinematic restraints which maintain both hands of the driver on the steering wheel, the involuntary response is determined for any possible vehicular acceleration Experimental verification was conducted for seven different hand positions with four subjects experiencing lateral acceleration Good correlation was obtained for all modes /Author/
TL;DR: In this article, a transmission consisting of three non-collinear shafts connected in sequence by two Hooke's joints is described, and a single differential equation governing the motion is derived, and is solved approximately by a method of small perturbations.
Abstract: A transmission consisting of three non-collinear shafts connected in sequence by two Hooke's joints is described. Each shaft has a specified moment of inertia, and power is transmitted from one end of the system to the other. Elastic and other deformations are neglected. A single differential equation governing the motion is derived, and is solved approximately by a method of small perturbations. The solution shows that at a constant mean speed the system will experience speed fluctuations which are complex functions of its dynamic parameters, including inertia and torque characteristics, as well as the more familiar kinematic parameters such as angularities of the joints.Special cases relating to constant speed conditions at chosen points in the system are assessed, and the effects of the significant parameters are illustrated numerically for a single-joint arrangement.
TL;DR: In this paper, a time-of-flight technique is used to separate interfering kinematic events without the loss of any experimental information, and preliminary results indicate that the technique can be used to distinguish three body final state reactions at low energy in which two nonidentical charged particles are detected.