scholarly journals Inner pressure prediction of suction cup based on Bernoulli equation

2021 ◽  
Vol 18 ◽  
pp. 100139
Author(s):  
Yang Tian ◽  
Shugen Ma ◽  
Genki Kotani
Keyword(s):  
Bernoulli Equation ◽  
Suction Cup ◽  
Inner Pressure

Techniques for preparing the Lolium perenne coleorhiza for scanning electron microscope evaluation

1992 ◽  
Vol 50 (1) ◽  
pp. 766-767
Author(s):  
Susan B.G. Debaene ◽  
John S. Gardner ◽  
Phil S. Allen
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Lolium Perenne ◽  
Morphological Study ◽  
Root Hairs ◽  
Inner Pressure ◽  
Water Potentials ◽  
Radicle Emergence ◽  
Standard Fixation ◽  
Scanning Electron

The coleorhiza is a nonvascular sheath that encloses the embryonic radicle in Poaceae, and is generally the first tissue to emerge during germination. Delicate hairlike extensions develop from some coleorhiza cells prior to radicle emergence. Similar to root hairs, coleorhiza hairs are extremely sensitive to desiccation and are damaged by exposure to negative water potentials. The coleorhiza of Lolium perenne is somewhat spherical when first visible, after which a knob forms at a right angle to the caryopsis due to inner pressure from the elongating radicle. This knob increases in length until the radicle finally punctures the coleorhiza. Standard fixation procedures cause severe desiccation of coleorhiza cells and hairs, making morphological study of the coleorhiza difficult. This study was conducted to determine a more successful process for coleorhiza preservation.

A Note on the Application of the Extended Bernoulli Equation

1999 ◽  
Author(s):  
Steven B. Segletes ◽  
William P. Walters
Keyword(s):  
Bernoulli Equation

Underwater Behavior of Blue Whales Using a Suction-cup Attached CRITTERCAM

2002 ◽  
Author(s):  
John Calambokidis ◽  
John Francis ◽  
Greg Marshall ◽  
Don Croll ◽  
Mark McDonald ◽  
...  
Keyword(s):  
Suction Cup ◽  
Blue Whales

An exact solution of fractional Euler-Bernoulli equation for a beam with fixed-supported and fixed-free ends

2021 ◽  
Vol 396 ◽  
pp. 125932
Author(s):  
Tomasz Blaszczyk ◽  
Jaroslaw Siedlecki ◽  
HongGuang Sun
Keyword(s):  
Exact Solution ◽  
Bernoulli Equation

ChemInform Abstract: Enhanced Superconductivity of SmFeAsO Co-Doped by Scandium and Fluorine to Increase Chemical Inner Pressure.

ChemInform ◽  
2012 ◽  
Vol 43 (48) ◽  
pp. no-no
Author(s):  
Haijie Chen ◽  
Ming Zheng ◽  
Aihua Fang ◽  
Jianhua Yang ◽  
Fuqiang Huang ◽  
...  
Keyword(s):  
Inner Pressure ◽  
Enhanced Superconductivity ◽  
Co Doped

The Lumped Capacitance Model for Unsteady Heat Conduction in Regular Solid Bodies With Natural Convection to Nearby Fluids Engages the Nonlinear Bernoulli Equation

2018 ◽  
Vol 10 (3) ◽  
Author(s):  
Antonio Campo
Keyword(s):  
Heat Conduction ◽  
Natural Convection ◽  
Heat Equation ◽  
Biot Number ◽  
Bernoulli Equation ◽  
Convective Coefficient ◽  
Unsteady Heat Conduction ◽  
The Mean ◽  
Capacitance Model ◽  
Solid Bodies

For the analysis of unsteady heat conduction in solid bodies comprising heat exchange by forced convection to nearby fluids, the two feasible models are (1) the differential or distributed model and (2) the lumped capacitance model. In the latter model, the suited lumped heat equation is linear, separable, and solvable in exact, analytic form. The linear lumped heat equation is constrained by the lumped Biot number criterion Bil=h¯(V/S)/ks < 0.1, where the mean convective coefficient h¯ is affected by the imposed fluid velocity. Conversely, when the heat exchange happens by natural convection, the pertinent lumped heat equation turns nonlinear because the mean convective coefficient h¯ depends on the instantaneous mean temperature in the solid body. Undoubtedly, the nonlinear lumped heat equation must be solved with a numerical procedure, such as the classical Runge–Kutta method. Also, due to the variable mean convective coefficient h¯ (T), the lumped Biot number criterion Bil=h¯(V/S)/ks < 0.1 needs to be adjusted to Bil,max=h¯max(V/S)/ks < 0.1. Here, h¯max in natural convection cooling stands for the maximum mean convective coefficient at the initial temperature Tin and the initial time t = 0. Fortunately, by way of a temperature transformation, the nonlinear lumped heat equation can be homogenized and later channeled through a nonlinear Bernoulli equation, which admits an exact, analytic solution. This simple route paves the way to an exact, analytic mean temperature distribution T(t) applicable to a class of regular solid bodies: vertical plate, vertical cylinder, horizontal cylinder, and sphere; all solid bodies constricted by the modified lumped Biot number criterion Bil,max<0.1.

scholarly journals Bio-inspired Miniature Suction Cups Actuated by Shape Memory Alloy

10.5772/7228 ◽  
2009 ◽  
Vol 6 (3) ◽  
pp. 29 ◽  
Author(s):  
Hu Bing-Shan ◽  
Wang Li-Wen ◽  
Fu Zhuang ◽  
Zhao Yan-zheng
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Analytical Model ◽  
Basic Structure ◽  
Thin Elastic Plate ◽  
Climbing Robots ◽  
Suction Cup ◽  
Sma Actuator ◽  
Suction Cups ◽  
Pressure Suction

Wall climbing robots using negative pressure suction always employ air pumps which have great noise and large volume. Two prototypes of bio-inspired miniature suction cup actuated by shape memory alloy (SMA) are designed based on studying characteristics of biologic suction apparatuses, and the suction cups in this paper can be used as adhesion mechanisms for miniature wall climbing robots without air pumps. The first prototype with a two-way shape memory effect (TWSME) extension TiNi spring imitates the piston structure of the stalked sucker; the second one actuated by a one way SMA actuator with a bias has a basic structure of stiff margin, guiding element, leader and elastic element. Analytical model of the second prototype is founded considering the constitutive model of the SMA actuator, the deflection of the thin elastic plate under compound load and the thermo-dynamic model of the sealed air cavity. Experiments are done to test their suction characteristics, and the analytical model of the second prototype is simulated on Matlab/simulink platform and validated by experiments.

scholarly journals Soft Hybrid Suction Cup Capable of Sticking to Various Objects and Environments

Actuators ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 50
Author(s):  
Hideyuki Tsukagoshi ◽  
Yuichi Osada
Keyword(s):  
Vertical Direction ◽  
Check Valve ◽  
Adhesive Force ◽  
Outer Diameter ◽  
Shear Direction ◽  
Concrete Walls ◽  
Suction Force ◽  
Suction Cup ◽  
Valve Function ◽  
Suction Cups

A universal suction cup that can stick to various objects expands the areas in which robots can work. However, the size, shape, and surface roughness of objects to which conventional suction cups can stick are limited. To overcome this challenge, we propose a new hybrid suction cup structure that uses the adhesive force of sticky gel and the suction force of negative pressure. In addition, a flexible and thin pneumatic balloon actuator with a check valve function is installed in the interior, enabling the controllable detachment from objects. The prototype has an outer diameter of 55 mm, a weight of 18.8 g, and generates an adsorption force of 80 N in the vertical direction and 60 N in the shear direction on porous walls where conventional suction cups struggle to adsorb. We confirmed that parts smaller than the suction cup and fragile potato chips are adsorbed by the prototype. Finally, the effectiveness of the proposed method is verified through experiments in which a drone with the prototypes can be attached to and detached from concrete walls and ceilings while flying; the possibility of adsorption to dusty and wet plates is discussed.

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