Deflection Maps of Elastic Catenary Cable-Driven Robots

2019 ◽  
Author(s):  
Leila Notash
Keyword(s):  
Center Of Mass ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cable Model ◽  
Cross Sectional ◽  
Cable Tension ◽  
Cable Properties ◽  
Manipulator Design ◽  
Deflection Limit ◽  
Cable Robots

Abstract In this paper, the cable tension and platform deflection of cable-robots are investigated. The significance of cable density, elasticity and cross-sectional area; platform mass, radius and center of mass; external wrench and platform orientation on the cable tension, platform deflection and workspace of the planar cable robots is investigated. It is shown that, in addition to cable mass, the effect of external wrench on the workspace of catenary cable model could be more prominent. Moreover, design issues and parameters affecting the manipulator deflection are examined, and those that would result in disjointed workspace regions and deflection maps are identified. It is presented that the change in deflection is gradual throughout the workspace for constant external wrench. For the catenary model, depending on the cable properties, platform orientation, manipulator design, and external wrench, the workspace with deflection limit may consist of disconnected regions.

Deflection Maps of Planar Elastic Catenary Cable-Driven Robots

2020 ◽  
Vol 12 (2) ◽  
Author(s):  
Leila Notash
Keyword(s):  
Center Of Mass ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Design Issues ◽  
Cable Model ◽  
Cross Sectional ◽  
Cable Tension ◽  
Cable Properties ◽  
Manipulator Design ◽  
Deflection Limit

Abstract In this paper, the cable tension and platform deflection of cable-driven robots are studied. The significance of cable density, elasticity, and cross-sectional area; platform mass, radius, and center of mass; the external wrench and platform orientation on the cable tension, platform deflection, and workspace of the planar cable robots is investigated. It is shown that, in addition to the cable mass, external wrench has a more prominent effect on the workspace of the catenary cable model. Moreover, design issues and parameters affecting the manipulator deflection are examined, and those that would result in disjointed workspace regions and deflection maps are identified. It is presented that the change in the deflection is gradual throughout the workspace for a constant external wrench. For the catenary model, depending on the cable properties, platform orientation, manipulator design, and external wrench, the workspace with the deflection limit may consist of disconnected regions.

EP-1101 RECTAL AIR REMOVAL REDUCES RECTAL CROSS-SECTIONAL AREA BUT DOESN'T MODIFY CENTER OF MASS OF PELVIC ORGANS

2012 ◽  
Vol 103 ◽  
pp. S425-S426
Author(s):  
S. Sabater ◽  
I. Andres ◽  
V. De la Vara ◽  
M.J. Muñoz ◽  
E. Jimenez ◽  
...  
Keyword(s):  
Center Of Mass ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Pelvic Organs ◽  
Air Removal

Workspace Investigation of Cable-Driven Robots With Non-Negligible Cable Mass and Antipodal Method

2018 ◽  
Author(s):  
Leila Notash ◽  
Derek McColl
Keyword(s):  
Linear Model ◽  
External Force ◽  
Robot Manipulators ◽  
Cable Model ◽  
Design Constraints ◽  
Cable Tension ◽  
Cable Properties ◽  
Manipulator Design ◽  
Workspace Boundary

The significance of gravity, cable density and elasticity on cable tension and manipulator workspace is investigated. Formulations of the cable tension vector are discussed. In addition, implementation of the antipodal theorem criteria for the workspace boundary characterization of planar cable-driven robot manipulators is presented when the mass and elasticity of cables are included. It is demonstrated that unlike the linear model, the external force could have more prominent effect on the workspace. Specifically, depending on the cable properties, platform orientation and manipulator design constraints, for the catenary cable model, the extended workspace due to external wrench may be divided into disjoint regions.

Pelvic Canal Narrowing Caused by Triple Pelvic Osteotomy in the Dog

1994 ◽  
Vol 07 (03) ◽  
pp. 110-113 ◽  
Author(s):  
D. L. Holmberg ◽  
M. B. Hurtig ◽  
H. R. Sukhiani
Keyword(s):  
Postoperative Complications ◽  
Pelvic Osteotomy ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Canal Width ◽  
Operative Complications ◽  
Post Operative Complications

SummaryDuring a triple pelvic osteotomy, rotation of the free acetabular segment causes the pubic remnant on the acetabulum to rotate into the pelvic canal. The resulting narrowing may cause complications by impingement on the organs within the pelvic canal. Triple pelvic osteotomies were performed on ten cadaver pelves with pubic remnants equal to 0, 25, and 50% of the hemi-pubic length and angles of acetabular rotation of 20, 30, and 40 degrees. All combinations of pubic remnant lengths and angles of acetabular rotation caused a significant reduction in pelvic canal-width and cross-sectional area, when compared to the inact pelvis. Zero, 25, and 50% pubic remnants result in 15, 35, and 50% reductions in pelvic canal width respectively. Overrotation of the acetabulum should be avoided and the pubic remnant on the acetabular segment should be minimized to reduce postoperative complications due to pelvic canal narrowing.When performing triple pelvic osteotomies, the length of the pubic remnant on the acetabular segment and the angle of acetabular rotation both significantly narrow the pelvic canal. To reduce post-operative complications, due to narrowing of the pelvic canal, overrotation of the acetabulum should be avoided and the length of the pubic remnant should be minimized.

DETERMINATION OF THE FUNCTION OF THE ROD’S CROSS-SECTIONAL AREA USING VIBRATION EIGENFREQUENCIES

2020 ◽  
Vol 0 (4) ◽  
pp. 19-24
Author(s):  
I.M. UTYASHEV ◽  
◽  
A.A. AITBAEVA ◽  
A.A. YULMUKHAMETOV ◽  
◽  
...  
Keyword(s):  
Cross Sectional Area ◽  
Variable Cross ◽  
Sectional Area ◽  
Longitudinal Vibrations ◽  
Cross Sectional ◽  
Method Error ◽  
Various Boundary Conditions ◽  
Elastic Fixation ◽  
Crosssectional Area

The paper presents solutions to the direct and inverse problems on longitudinal vibrations of a rod with a variable cross-sectional area. The law of variation of the cross-sectional area is modeled as an exponential function of a polynomial of degree n . The method for reconstructing this function is based on representing the fundamental system of solutions of the direct problem in the form of a Maclaurin series in the variables x and λ. Examples of solutions for various section functions and various boundary conditions are given. It is shown that to recover n unknown coefficients of a polynomial, n eigenvalues are required, and the solution is dual. An unambiguous solution was obtained only for the case of elastic fixation at one of the rod’s ends. The numerical estimation of the method error was made using input data noise. It is shown that the error in finding the variable crosssectional area is less than 1% with the error in the eigenvalues of longitudinal vibrations not exceeding 0.0001.

Changes in the parameters of nasal breathing and parameters of the upper respiratory tract during orthognathic operations in patients with II and III skeletal class of jaw anomalies

2020 ◽  
pp. 22-27
Author(s):  
S.Sh. Gammadaeva ◽  
M.I. Misirkhanova ◽  
A.Yu. Drobyshev
Keyword(s):  
Respiratory Tract ◽  
Nasal Cavity ◽  
Nasal Septum ◽  
Cross Sectional Area ◽  
Upper Respiratory Tract ◽  
Sectional Area ◽  
Nasal Breathing ◽  
Cross Sectional ◽  
Skeletal Class ◽  
Upper Respiratory

The study analyzed the functional parameters of nasal breathing, linear parameters of the nasal aperture, nasal cavity and nasopharynx, volumetric parameters of the upper airways in patients with II and III skeletal class of jaw anomalies before and after orthognathic surgery. The respiratory function of the nose was assessed using a rhinomanometric complex. According to rhinoresistometry data, nasal resistance and hydraulic diameter were assessed. According to the data of acoustic rhinometry, the minimum cross-sectional area along the internal valve, the minimum cross-sectional area on the head of the inferior turbinate and nasal septum and related parameters were estimated. According to the CBCT data, the state of the nasal septum, the inferior turbinates, the nasal aperture, the state of the nasal cavity, and the linear values of the upper respiratory tract (nasopharynx) were analyzed. The patients were divided into 4 groups according to the classification of the patency of the nasal passages by

Unequal Probability Scheme for Fruit Count in a Guava Tree

2016 ◽  
Vol 3 (4) ◽  
Author(s):  
R. C. BHARATI
Keyword(s):  
Cross Sectional Area ◽  
Equal Probability ◽  
Sampling Scheme ◽  
Research Station ◽  
Sectional Area ◽  
Cross Sectional ◽  
Unequal Probability ◽  
Selection Probabilities ◽  
Horticultural Research ◽  
Number Of Branches

Data on fruit count corresponding to primary, secondary and tertiary branches of a randomly selected guava CV. Allahabad Safeda were recorded from the guava orchard of Horticultural Research Station, Birauli. The proposed sampling scheme in which the selection probabilities are based on length of braches between two forking points was compared with equal probability(PE), probability proportional to the number of branches(PPN), probability proportional to the cross sectional area (PPA) and probability proportional to volume (PPV) method of sampling and found to be more efficient.

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