Dynamics of an Overconstrained Shaft Coupling

1986 ◽  
Vol 108 (4) ◽  
pp. 497-505 ◽  
Author(s):  
Tyng Liu ◽  
Ting W. Lee
Keyword(s):  
Experimental Method ◽  
Matrix Method ◽  
Dynamic State ◽  
Primary Concern ◽  
Force Analysis ◽  
General Applicability ◽  
Analytical Technique ◽  
Axial Forces ◽  
Spatial Mechanisms ◽  
Statics And Dynamics

This paper presents a method for complete force analysis, including both statics and dynamics, of overconstrained, statically indeterminate spatial mechanisms. Of primary concern is the development of a method which is realistic and has general applicability. The usual tacit assumption of the vanishing of certain force and torque components in the analysis, such as zero axial forces at joints, is removed. The method combines an analytical technique—using the [3 × 3] screw matrix method—coupled with an experimental method to completely specify the dynamic state of an overconstrained mechanism. The indeterminate force is modeled using a characteristic equation simulated experimentally. The method is illustrated in the case of the UNI-LAT coupling which is a modified Hooke-type joint. Based on the analytical results, some physical insights are interpreted. It was found that overclosure affects mechanism performance and plays an important role in the dynamics of the UNI-LAT coupling. General guidelines on the design of the UNI-LAT coupling are also presented.

Force Analysis on the Opening/Closing Mechanism in the Door of Coal Hopper Car Based on the Matrix Method

2012 ◽  
Vol 591-593 ◽  
pp. 84-87
Author(s):  
Chao Yan Wan ◽  
Xu Zhao ◽  
Pei Xing Li
Keyword(s):  
Matrix Method ◽  
Force Analysis ◽  
Complex Problems ◽  
The Matrix ◽  
Simulation And Experiment ◽  
Selection Of ◽  
Closing Mechanism

Based on the matrix method of the mechanism, to build the force matrices equation of the opening/closing mechanism of the door of coal hopper car. Taking the opening state as example, finishing the solution of the force of the mechanism. Using this method, the reaction of the joint and the thrust of the cylinder can be solved in any position. The results provide theoretical bases for selection of cylinders and design of the mechanism. This method can solve some complex problems easily which are difficult to the method of “first solving motion pair”. Besides that, this method can be combined with simulation and experiment to show their respective advantages. In research, satisfying result can be obtained by using all the methods synthetically.

Design of a Directional Coupler based on UV-Induced LiNbO3 Waveguides

2017 ◽  
Vol 38 (3) ◽  
Author(s):  
T. Ghosh ◽  
B. Samanta ◽  
P. C. Jana ◽  
P. Ganguly
Keyword(s):  
Matrix Method ◽  
Directional Coupler ◽  
Continuous Wave ◽  
Effective Index ◽  
Coupling Length ◽  
Pure Bending ◽  
Analytical Technique ◽  
Bending Loss ◽  
Transition Length

AbstractA semi-analytical technique, effective index-based matrix method (EIMM), has been applied to determine the coupling length of continuous wave UV-written directional coupler for different gaps between the waveguides as well as the pure bending loss and transition loss of S-curved waveguides estimated to optimize the transition length (

Inertia Force Analysis of Spatial Mechanisms

1971 ◽  
Vol 93 (1) ◽  
pp. 27-32 ◽  
Author(s):  
An Tzu Yang
Keyword(s):  
Closed Form ◽  
Mechanical System ◽  
Dynamic Equation ◽  
Geometric Interpretation ◽  
Analytical Tool ◽  
Inertia Force ◽  
Force Analysis ◽  
Digital Computation ◽  
Spatial Mechanisms ◽  
Analytical Expressions

A dual dynamic equation, based on dual vectors and screw calculus, is formulated here to provide a concise analytical tool for the study of the dynamics of rigid members in any complex mechanical system. In this paper the equation is applied to inertia force analysis of an RCCC mechanism of general proportions; bearing reactions and inertia torque are obtained in closed form dual-number expressions. Such analytical expressions are more susceptible for geometric interpretation and well adapted for digital computation.

scholarly journals A study on weight-on-bit data correction method of a near-bit measuring tool

2019 ◽  
Vol 11 (1) ◽  
pp. 168781401882151 ◽  
Author(s):  
Xiaofeng Xu ◽  
Yingfeng Meng ◽  
Yonghui Liu ◽  
Yueying Ji
Keyword(s):  
Drilling Fluid ◽  
Drill String ◽  
Measured Data ◽  
Differential Pressure ◽  
Well Testing ◽  
Force Analysis ◽  
The Real ◽  
Axial Forces ◽  
Weight On Bit ◽  
Measuring Tool

The real weight on bit is difficult to observe or estimate in highly deviated wells and extended-reach wells since complex loads are acted on drill string. Near-bit measurement while drilling tools, which are generally used to address this issue, can only measure axial forces based on axial strains instead of the real WOB. Axial forces on near-bit drill string are mainly controlled by buoyancy force of drilling fluid, circulating pressure, and other factors. To some extent, the measured data can be corrected by force analysis. It should be noted that experiments must be conducted to study the influences of differential pressure and temperature on measured WOB data of near-bit measuring tool. This article presents calculating method of real WOB via correction of measured data, based on force analysis of a self-developed near-bit measuring tool and experiments on influences of differential pressure and downhole temperature. Field test indicates that higher deviation angle will lead to a greater difference between real WOB and the indicated value at wellhead. Multi-well testing data verification indicates that this method is effective and reliable in extracting real WOB, and helpful to accurately identify the running state of bottom-hole assembly.

STATIC FORCE ANALYSIS OF MECHANISMS WITH FOUR-BAR LINKAGES BASED ON FLEXIBILITY CONDITIONS

2005 ◽  
Vol 29 (4) ◽  
pp. 605-616
Author(s):  
Sureyya Sahin ◽  
Leila Notash
Keyword(s):  
External Loading ◽  
Static Force ◽  
Force Analysis ◽  
Spatial Mechanisms ◽  
The Matrix ◽  
Method Of Solution ◽  
Free Body ◽  
Four Bar Linkage ◽  
Additional Constraints ◽  
Structural Matrix

The four-bar linkages are widely used in both planar and spatial mechanisms and robotic manipulators. Static force analysis of the four-bar mechanisms subjected to spatial external loading working under gravitational forces is formulated in this article. The formulation is based on structural matrix force and stiffness methods with the free-body diagrams for each of the links considered. The four-bar mechanism considered is over-determined as there are additional constraints compared to a statically determined four-bar mechanism. A method of solution, based on the matrix force analysis, incorporating the flexibility of the mechanism is given. The methodology is simulated for a mechanism with a planar four-bar linkage where the plane of motion could be varied by rotating about a revolute joint that connects the four-bar linkage to the base.

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