MOTION EQUATION OF TOOTH BLADE OF SPIRAL-PLATE WORKING UNIT IN SPACE

2016 ◽  
Vol 11 (1) ◽  
pp. 66-69 ◽  
Author(s):  
Шириязданов ◽  
Rustem Shiriyazdanov ◽  
Пикмуллин ◽  
Gennadiy Pikmullin ◽  
Юнусов ◽  
...  
Keyword(s):  
Coordinate System ◽  
Logarithmic Spiral ◽  
Helix Angle ◽  
Motion Equation ◽  
Cutting Edge ◽  
Helical Surface ◽  
Spatial Coordinate ◽  
Spiral Plate ◽  
Angle Of Rotation

The article deals with the spiral-plate working unit, configured with teeth, the cutting edge (blade) of which is made on site (curve) of the logarithmic spiral. Each helix of studied working unit (taking into account properties of a helical surface or a line) is set at an angle and lift the helix has an angle of rotation generator (i.e., the helix angle of twist). In this case, to create the motion equation of any point of the teeth’s motion, the working unit is in the spatial coordinate system 0xyz so that the origin was in his heart.

scholarly journals Genetic Algorithm in the Computation of the Camera External Orientation

2012 ◽  
Vol 9 ◽  
pp. 5-16
Author(s):  
Rudolf Urban ◽  
Martin Štroner
Keyword(s):  
Genetic Algorithm ◽  
Coordinate System ◽  
Control Points ◽  
Generic Algorithm ◽  
Matrix Inverse ◽  
Computation Procedure ◽  
Spatial Coordinate ◽  
The Matrix ◽  
Computer Based ◽  
Calculation Models

The article addresses the solution of the external orientation of the camera by means of a generic algorithm which replaces complicated calculation models using the matrix inverse. The computation requires the knowledge of four control points in the spatial coordinate system and the image coordinate system. The computation procedure fits very well computer-based solutions thanks to it being very simple.

scholarly journals Development of Periodic Unsteady Turbulent Wakes in a Curved Channel at Zero Streamwise Pressure Gradient

1994 ◽  
Author(s):  
M. T. Schobeiri ◽  
J. John
Keyword(s):  
Pressure Gradient ◽  
Coordinate System ◽  
Reynolds Stress ◽  
Temporal Distribution ◽  
Curved Channel ◽  
Spatial Coordinate ◽  
Curved Channels ◽  
Turbulent Wakes ◽  
Streamwise Pressure Gradient ◽  
Hot Film

The development of turbomachinery wake flows is influenced by streamline curvature and streamwise pressure gradient. This paper is a part of a comprehensive experimental and analytical study on the development of the steady and periodic unsteady turbulent wakes in curved channels at different longitudinal (streamwise) pressure gradients. The development of periodic unsteady wakes in a curved channel at zero longitudinal pressure gradient is reported in this paper. Instantaneous velocity components of the periodic wakes, measured using a X-hot-film probe, are analyzed by employing phase-averaging techniques. The temporal distribution of phase-averaged velocity and Reynolds stress components obtained in stationary frame of reference are transformed to a relative spatial coordinate system. The profiles of the velocity and Reynolds stress distribution in relative spatial coordinate system and similarity coordinates are consistent with the measurements of the wake development behind stationary cylinder in the same curved channel.

Improvement of Chip Evacuation in Drilling of Lead-Free Brass Using Micro Drill

2014 ◽  
Vol 8 (6) ◽  
pp. 874-879 ◽  
Author(s):  
Hideharu Kato ◽  
◽  
Shingo Nakata ◽  
Noriaki Ikenaga ◽  
Hiroaki Sugita ◽  
...  
Keyword(s):  
Thrust Force ◽  
Helix Angle ◽  
Cutting Edge ◽  
Lead Free ◽  
Deep Drilling ◽  
Discharge Performance ◽  
Aspect Ratios ◽  
The Impact ◽  
Micro Drill ◽  
Small Holes

As the miniaturization of integrated circuits has progressed, the penetration holes of bonding jigs have become smaller. However, micro drills have a tendency to break when drilling small holes with high aspect ratios. Moreover, to reduce the impact on the environment, there has been a recent trend towards the use of lead-free brass as jig materials, but these are very difficult to drill. In the present study, small holes are drilled in lead-free brass using a micro drill, and the effects of web thinning, the helix angle, and the nick geometry on chip evacuation are investigated. The results indicate that drills with a helix angle of 15° have the longest tool life. The formation of a nick on the cutting edge is found to help decrease the thrust force during deep drilling. A drill with a relatively shallow nick perpendicular to the cutting edge have excellent chip discharge performance, and its cutting force is stable. Nick treatment effectively decreases the thrust force at a deep drilling position.

The Fluid-Structure Interaction Analysis of the Inverted Umbrella Aerator Curved Blade

2014 ◽  
Vol 705 ◽  
pp. 101-105 ◽  
Author(s):  
Pu Xing ◽  
Ai Min Zhang ◽  
Zhi Xiong Deng
Keyword(s):  
Interaction Analysis ◽  
Fluid Structure Interaction ◽  
Logarithmic Spiral ◽  
Helix Angle ◽  
Fluid Structure ◽  
Structure Interaction ◽  
Variable Helix ◽  
Curved Blade ◽  
New Type ◽  
Spiral Line

The blades are important components of the inverted umbrella aerators. In this paper, the inverted umbrella aerator blade with curved surface, which was arranged according to the variable helix angle of logarithmic spiral line, was designed and simulated. Through the simulation and calculation of the flow field of oxidation ditch that pushed by the blade, based on the fluid-structure interaction analysis, the reliability of the impeller blades has been studied. All the results showing that the new type inverted umbrella surface aerator blade is reliable.

The Spatial Characteristics of Tactile Form Perception

Perception ◽  
1983 ◽  
Vol 12 (5) ◽  
pp. 615-626 ◽  
Author(s):  
Simon R Oldfield ◽  
John R Phillips
Keyword(s):  
Coordinate System ◽  
Mirror Image ◽  
Form Perception ◽  
Spatial Characteristics ◽  
Tactual Perception ◽  
Spatial Coordinate ◽  
Spatial Coordinates ◽  
Object Form ◽  
Skin Receptors

The perceived orientation of a raised letterform indenting the skin of the finger reverses (from normal to its mirror-image) when the letter is held in contact with the finger and both are rotated through 180° about the axis of the finger. Thus, though the pattern of stimulated skin receptors remains constant, the perceived orientation of the letter reverses. On the basis of this observation it is proposed that tactual perception of object form involves assignment of a spatial coordinate system within which the patterns of skin stimulation are interpreted. In experiments in which the orientations of letters and subjects are systematically varied within the environment, the occurrence or nonoccurrence of reversal in perceived orientation of letters has been used to investigate the origin of the proposed spatial coordinate system; that is, whether it is assigned with respect to the observer (egocentrically) or with respect to the environment (geocentrically). The results indicate that the assignment of coordinates is determined by both egocentric and geocentric factors. It is proposed that the reversal phenomena observed in these experiments, and in experiments of others which involve drawing characters on the skin, are consistent with Gibson's proposal that it is object form which is directly perceived, but that this involves interpretation of the patterns of skin stimulation within a framework of spatial coordinates.

Principle and Practice of the Measurement for Hourglass Worms and Hobs

2017 ◽  
Vol 870 ◽  
pp. 191-196
Author(s):  
Bo Yu ◽  
Zhao Yao Shi ◽  
Yong Ye ◽  
Lu Yan ◽  
Ying Fu ◽  
...  
Keyword(s):  
Coordinate System ◽  
Critical Issue ◽  
Tooth Profile ◽  
Cutting Edge ◽  
Transmission Performance ◽  
Profile Deviation ◽  
Cylindrical Coordinate ◽  
Geometric Deviations ◽  
Worm Gears ◽  
Measuring Machine

Compared with cylindrical worm gears, hourglass worm gears have better transmission performance. The measurement of the hourglass worms and the hobs is a critical issue to restrict the application of the hourglass worm gear transmission. To solve this problem, an hourglass worm and hob measuring principle and a measuring machine which achieves the inspection of each deviation are proposed. In this paper, the measuring principle is explained. The models of the deviations based on the cylindrical-coordinate system are determined. The machine controls the movement of the probe in accordance with the path created by the models. By checking the geometric deviations, including the helix deviation and the axial tooth profile deviation of the worm, and the cutting edge helix deviation and the cutting edge tooth profile deviation of the hob, the principle is proved to be feasible.

Machining-Induced Residual Stress: Experimentation and Modeling

1999 ◽  
Vol 122 (1) ◽  
pp. 20-31 ◽  
Author(s):  
Kurt Jacobus ◽  
R. E. DeVor ◽  
S. G. Kapoor
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
Design Of Experiments ◽  
Coordinate System ◽  
Cutting Tool ◽  
Metal Flow ◽  
Cutting Edge ◽  
Principal Directions ◽  
Stress Profiles ◽  
Aisi 4340

Controlled orthogonal and controlled oblique machining of annealed AISI 4340 have been undertaken in a design of experiments framework to investigate the machining-induced residual stresses resulting from these processes. The experimentation demonstrates significant simplifications in the machining-induced residual stress problem when the stresses are expressed in a coordinate system fixed in the tool and also indicates that the directions along the cutting edge and normal to the cutting edge of the tool are principal directions of the machining-induced residual stresses. Based on the experimental results, a plane strain thermoelastoplastic model of metal flow under the flank of a cutting tool is developed to predict the full in-plane biaxial residual stress profiles existing at and beneath the newly created surface. Calibrated results show favorable agreement with the experimental machining-induced residual stresses in annealed AISI 4340. [S1087-1357(00)00201-X]

Load-Deflection Behavior of Conical Spiral Compression Springs

1962 ◽  
Vol 84 (3) ◽  
pp. 329-337
Author(s):  
Han-Chung Wang ◽  
Will J. Worley
Keyword(s):  
Strain Energy ◽  
Large Diameter ◽  
Logarithmic Spiral ◽  
Nonlinear Effects ◽  
Helix Angle ◽  
Lateral Load ◽  
Energy Methods ◽  
The Third ◽  
Compression Springs ◽  
Third Dimension

The geometry of both the Archimedean and the logarithmic spiral, when formed into the third dimension, is considered. Changes in profile resulting from the choice of constant helix angle and from constant spacing between adjacent coils along the axis of the conic are presented. The axial and lateral load-deflection behavior of conical spiral springs is considered in terms of the above variables. Strain-energy methods are used to obtain the load-deflection relationships. Nonlinear effects due to compression of the large diameter coils are discussed.

scholarly journals Mathematical Model of Human Semicircular Canal Spatial Attitude 

2021 ◽  
Author(s):  
Shu-zhi Wu ◽  
Ping Lin ◽  
Yan-yan Zheng ◽  
Yi-fei Zhou ◽  
Xiao-kai Yang
Keyword(s):  
Mathematical Model ◽  
Coordinate System ◽  
Semicircular Canal ◽  
Average Method ◽  
Vestibular Function ◽  
Semicircular Canals ◽  
Normal Vector ◽  
Spatial Coordinate ◽  
Average Value ◽  
Plane Normal

Abstract Located deep in the temporal bone, the semicircular canal is a subtle structure that requires a spatial coordinate system for measurement and observation. In this study,Fifty-five semicircular canal and eyeball models were obtained by segmentation of MRI data. The spatial coordinate system was established by taking the top of the common crus and the bottom of eyeball as the horizontal plane. Firstly, the plane equation is calculated according to the centerline of the semicircular canals. Then, according to the parameters of the plane equation, the plane normal vectors are obtained. Finally, the average unit normal vector of each semicircular canal plane can be obtained by calculating the average value of the vectors. It is more intuitive and accurate to calculate the average normal vector of semicircular canal plane with the vector average method, which is different from the angular average method in different degrees. The mathematical model of semicircular canal spatial attitude established in this study is more reliable, which can guide the vestibular function examination, and also help guide the diagnosis and treatment of BPPV.

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