COMPUTER PROCEDURE FOR SELECTING PARAMETERS OF THE PERIPHERAL DOCKING ASSEMBLY LATCH MECHANISM

2021 ◽  
pp. 42-52
Author(s):  
Ivan E. CHERNYSHEV
Keyword(s):  
Key Words ◽  
Software Tool ◽  
Load Carrying ◽  
Mode Of Operation ◽  
Computer Procedure

When developing the country’s made peripheral docking assembly consistent with the International Docking System Standard a task arose concerning reduction of dimensions of the latch mechanisms that ensure the capture. The article describes the mode of operation of these mechanisms. Proposed is a procedure which makes it possible to choose such a layout of their joints in which the links are inside a given area during operation. A uniform LPτ-sequence is used to form various options of the joints layout. A criterion of maximum loads acting on the links is described. It is shown that the dimensions of the existing latch mechanism can be decreased only with an increase of the load-carrying capability of the links. The proposed procedure is part of a software tool computerizing the design of a new latch mechanism. Key words: spacecraft docking, peripheral docking assembly, latch mechanism, capture, LPτ-sequence.

Equivalent slenderness ratio for built-up members

1993 ◽  
Vol 20 (4) ◽  
pp. 708-711 ◽  
Author(s):  
Murray C. Temple ◽  
Ghada Elmahdy
Keyword(s):  
Key Words ◽  
Carrying Capacity ◽  
Slenderness Ratio ◽  
Load Carrying Capacity ◽  
Lateral Deformation ◽  
Numerical Example ◽  
Ratio Equation ◽  
Load Carrying ◽  
The One ◽  
Equivalent Slenderness Ratio

Built-up struts that buckle about an axis perpendicular to the plane of the connectors should be treated as a "built-up" member as opposed to a "simple" member. This mode of buckling causes shear and moments in the connectors which deform the connectors. These deformations increase the lateral deformation of the member and hence affect the load-carrying capacity. To account for this effect the easiest method is to use an equivalent slenderness ratio such as the one included in the Canadian Standard. This note outlines the derivation of the equivalent slenderness ratio equation, discusses when it should and should not be used, and includes a numerical example. A rewording of the applicable clause in the Canadian Standard is suggested. Key words: battens, built-up members, connectors, slenderness ratio.

scholarly journals Balanced and unbalanced welds for angle compression members

1994 ◽  
Vol 21 (3) ◽  
pp. 396-403 ◽  
Author(s):  
Murray C. Temple ◽  
Sherief S. S. Sakla
Keyword(s):  
Key Words ◽  
Carrying Capacity ◽  
Compressive Load ◽  
Tensile Load ◽  
Effective Length ◽  
Load Carrying Capacity ◽  
Compression Members ◽  
Load Carrying ◽  
Compressive Loads ◽  
Compressive Resistance

Angles used as web members in trusses are often welded to the chords with unbalanced welds. This is necessary because of space limitations. It is not known what effect such a weld has on the compressive load carrying capacity of an angle. The standards and specification examined allow an unbalanced weld for an angle. The justification for using such a weld is based on research conducted on angles in tension. For these members, it was concluded that an unbalanced weld does not affect the tensile load carrying capacity of the angle. Research results for angles with different weld patterns subjected to compressive loads are not available in the literature. Eighteen tests were conducted on angle compression members with various weld patterns. It was determined that an unbalanced weld is detrimental to the load carrying capacity of an intermediate length angle but is beneficial for a slender angle. Key words: angles, column (structural), compressive resistance, effective length, standards, welds.

Interconnection of widely spaced angles

1988 ◽  
Vol 15 (4) ◽  
pp. 732-741 ◽  
Author(s):  
Murray C. Temple ◽  
Joo Chai Tan
Keyword(s):  
Key Words ◽  
Failure Mode ◽  
Carrying Capacity ◽  
Structural Design ◽  
Failure Load ◽  
Building Codes ◽  
Load Carrying Capacity ◽  
Insignificant Effect ◽  
Load Carrying ◽  
Theoretical Results

Research on the interconnection of widely spaced back-to-back angles has not been conducted. This research was carried out with the aim of developing rules for the design and spacing of interconnectors in such members. Four parameters—the number of interconnectors, the back-to-back spacing between angles, the weld pattern used to connect the interconnectors to the angles, and the thickness of the interconnectors—were studied. The experimental and the theoretical results for the slender double angles confirm that only one interconnector, of practical proportions, is required to make the widely spaced angles act as an integral unit. Both the separation between angles, within reason, and the weld pattern used to connect the interconnectors to the angles had an insignificant effect on the failure load and the failure mode. The thickness of the interconnector did affect the load-carrying capacity of the strut, but only when the thickness of the interconnector was impractically small. The forces and moments in the interconnectors are very small. Key words: angles, back-to-back, buckling, building (codes), columns (structural), design interconnection.

Arrangement of interconnectors for starred angle compression members

1994 ◽  
Vol 21 (1) ◽  
pp. 76-80 ◽  
Author(s):  
Murray C. Temple ◽  
Sherief S. S. Sakla ◽  
David Stchyrba ◽  
Douglas Ellis
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Key Words ◽  
Carrying Capacity ◽  
Building Codes ◽  
Load Carrying Capacity ◽  
Element Analysis ◽  
Compression Members ◽  
Load Carrying

Starred angles are commonly used as web members in trusses. Standards contain requirements which specify the number of interconnectors to be used, but most standards do not specify a preferred arrangement for the interconnectors. When plates are used as interconnectors, three arrangements — aligned, alternating, or cruciform — are possible. Nine starred angles, three with each arrangement of interconnectors, were tested. A finite element analysis was also conducted. It was determined that the arrangement of the interconnectors did not affect the load-carrying capacity of the starred angles. Key words: angles, buckling, building (codes), columns (structural) interconnection, starred angle.

On the Design of PAMINSA: A New Class of Parallel Manipulators With High-Load Carrying Capacity

2007 ◽  
Author(s):  
Se´bastien Briot ◽  
Sylvain Gue´gan ◽  
Eric Courteille ◽  
Vigen Arakelian
Keyword(s):  
Degrees Of Freedom ◽  
Significant Contribution ◽  
Parallel Manipulators ◽  
Dynamic Mode ◽  
Motion Generation ◽  
Static Loads ◽  
New Class ◽  
Load Carrying ◽  
Mode Of Operation ◽  
First Time

This paper deals with the new results concerning the topologically decoupled parallel manipulators called PAMINSA. The conceptual design of these manipulators, in which the copying properties of pantograph linkage are used, allows obtaining a large payload capability. A newly synthesized fully decoupled 3 degrees of freedom manipulator is discussed and a systematic approach for motion generation of input point of each limb is presented. It is shown that the conditions of complete static balancing of limbs are not effective in the case of dynamic mode of operation. This is approved by numerical simulations and experiments. A significant contribution of this paper is also the experimental validation of the suggested design concept. It is shown experimentally for the first time that the static loads on the rotating actuators, which displace the platform in the horizontal plane, are cancelled.

Enhancement of Contrast in the CEM and STEM Using Bumpy Specimens and Employing the “Dappled Field” Mode of Operation

1974 ◽  
Vol 32 ◽  
pp. 552-553 ◽  
Author(s):  
L. Gandolfi ◽  
J. Reiffel
Keyword(s):  
Operating Mode ◽  
Scanning Transmission Electron Microscope ◽  
Dark Field ◽  
Specimen Preparation ◽  
Field Mode ◽  
Preparation Methods ◽  
Scanning Transmission Electron ◽  
Transmission Electron ◽  
Mode Of Operation ◽  
Scanning Transmission

Calculations have been performed on the contrast obtainable, using the Scanning Transmission Electron Microscope, in the observation of thick specimens. Recent research indicates a revival of an earlier interest in the observation of thin specimens with the view of comparing the attainable contrast using both types of specimens.Potential for biological applications of scanning transmission electron microscopy has led to a proliferation of the literature concerning specimen preparation methods and the controversy over “to stain or not to stain” in combination with the use of the dark field operating mode and the same choice of technique using bright field mode of operation has not yet been resolved.

High-Voltage Scanning Electron Microscopy

1970 ◽  
Vol 28 ◽  
pp. 6-7
Author(s):  
J. M. Cowley
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Scanning Transmission Electron Microscopy ◽  
Wave Optics ◽  
Contrast Effects ◽  
Transmission Electron ◽  
Mode Of Operation ◽  
Scanning Transmission ◽  
Types Of Information ◽  
Voltage Scanning

The comparison of scanning transmission electron microscopy (STEM) with conventional transmission electron microscopy (CTEM) can best be made by means of the Reciprocity Theorem of wave optics. In Fig. 1 the intensity measured at a point A’ in the CTEM image due to emission from a point B’ in the electron source is equated to the intensity at a point of the detector, B, due to emission from a point A In the source In the STEM. On this basis it can be demonstrated that contrast effects In the two types of instrument will be similar. The reciprocity relationship can be carried further to include the Instrument design and experimental procedures required to obtain particular types of information. For any. mode of operation providing particular information with one type of microscope, the analagous type of operation giving the same information can be postulated for the other type of microscope. Then the choice between the two types of instrument depends on the practical convenience for obtaining the required Information.

Transmission Scanning Electron Microscopy and Energy Analysis with the Siemens ELMISKOP 101

1972 ◽  
Vol 30 ◽  
pp. 450-451
Author(s):  
H. M. Thieringer
Keyword(s):  
Objective Lens ◽  
Transmission Microscopy ◽  
Image Recording ◽  
Mode Of Operation ◽  
Scanning Transmission ◽  
Electron Microscopes ◽  
And Performance ◽  
Convergent Beam ◽  
Ray Path ◽  
Beam Diffraction

It has repeatedly been show that with conventional electron microscopes very fine electron probes can be produced, therefore allowing various micro-techniques such as micro recording, X-ray microanalysis and convergent beam diffraction. In this paper the function and performance of an SIEMENS ELMISKOP 101 used as a scanning transmission microscope (STEM) is described. This mode of operation has some advantages over the conventional transmission microscopy (CTEM) especially for the observation of thick specimen, in spite of somewhat longer image recording times.Fig.1 shows schematically the ray path and the additional electronics of an ELMISKOP 101 working as a STEM. With a point-cathode, and using condensor I and the objective lens as a demagnifying system, an electron probe with a half-width ob about 25 Å and a typical current of 5.10-11 amp at 100 kV can be obtained in the back focal plane of the objective lens.

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