Effects of Bionic Curves on Penetration Force under Difference Soils

Yunhai Ma; Huixin Wang; Jian Zhuang; Hongyan Qi; Jiangtao Yu

doi:10.3390/app10020529

Effects of Bionic Curves on Penetration Force under Difference Soils

Applied Sciences ◽

10.3390/app10020529 ◽

2020 ◽

Vol 10 (2) ◽

pp. 529

Author(s):

Yunhai Ma ◽

Huixin Wang ◽

Jian Zhuang ◽

Hongyan Qi ◽

Jiangtao Yu

Keyword(s):

Simulation Analysis ◽

Soil Surface ◽

Friction Angle ◽

Penetration Process ◽

Force Increase ◽

Penetration Force ◽

Increase Rate ◽

Force Direction ◽

Force Reduction ◽

Depth Curve

Soil penetration is the most important process during soil tilling. To optimize the soil penetration process, six specimens were designed and fabricated based on the badger teeth outlines. Both experimental investigation and numerical analysis were conducted with three types of soil. Results showed the specimen C, B, and D got the lowest penetration force and reduced the force by 26.15%, 22.68%, and 25.86% compared with that of specimen A under soil 1, soil 2, and soil 3, respectively. Depth-force curve analysis showed that the bionic specimens can slow down the force increase rate by reducing the coefficient of the force-depth curve equations. The bionic specimens obtained a lower increase of internal friction angle and cohesion after penetration, indicating the soil strength after penetration was lower. Furthermore, the rise in soil surface was observed after the penetration, and the penetration with the bionic specimens got a higher rise. Simulation analysis showed that the mechanism for the force reduction was because the force direction was changed, which brought a better flowability and less strength for the soil. It concludes that the badger teeth outlines reduce the penetration force by changing the force directions and optimizing the soil properties. Based on research results, the optimal bionic curve for penetration in different types of soil was determined.

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Sand- and Clay-Photocured-Geomembrane Interface Shear Characteristics Using Direct Shear Test

Sustainability ◽

10.3390/su13158201 ◽

2021 ◽

Vol 13 (15) ◽

pp. 8201

Author(s):

Lihua Li ◽

Han Yan ◽

Henglin Xiao ◽

Wentao Li ◽

Zhangshuai Geng

Keyword(s):

Soil Surface ◽

Friction Angle ◽

Direct Shear ◽

Tensile Crack ◽

Shear Tests ◽

Interface Shear ◽

Direct Shear Tests ◽

Carbon Black Powder ◽

Shear Characteristics ◽

Impermeable Layer

It is well known that geomembranes frequently and easily fail at the seams, which has been a ubiquitous problem in various applications. To avoid the failure of geomembrane at the seams, photocuring was carried out with 1~5% photoinitiator and 2% carbon black powder. This geomembrane can be sprayed and cured on the soil surface. The obtained geomembrane was then used as a barrier, separator, or reinforcement. In this study, the direct shear tests were carried out with the aim to investigate the interfacial characteristics of photocured geomembrane–clay/sand. The results show that a 2% photoinitiator has a significant effect on the impermeable layer for the photocured geomembrane–clay interface. As for the photocured geomembrane–sand interface, it is reasonable to choose a geomembrane made from a 4% photoinitiator at the boundary of the drainage layer and the impermeable layer in the landfill. In the cover system, it is reasonable to choose a 5% photoinitiator geomembrane. Moreover, as for the interface between the photocurable geomembrane and clay/sand, the friction coefficient increases initially and decreases afterward with the increase of normal stress. Furthermore, the friction angle of the interface between photocurable geomembrane and sand is larger than that of the photocurable geomembrane–clay interface. In other words, the interface between photocurable geomembrane and sand has better shear and tensile crack resistance.

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3D Dynamic Finite Element Simulation Analysis of Single Abrasive Grain during Profile Grinding with Axial Feed

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.680.410 ◽

2013 ◽

Vol 680 ◽

pp. 410-416 ◽

Cited By ~ 4

Author(s):

Jun Ming Wang ◽

Fu Yuan Tong ◽

Xiao Xue Li

Keyword(s):

Finite Element ◽

Finite Element Simulation ◽

Simulation Analysis ◽

Tangential Force ◽

Profile Grinding ◽

Software Analysis ◽

Dynamic Finite Element ◽

Abrasive Grain ◽

Element Simulation ◽

Force Increase

By simplifying the geometric shape of abrasive grain in a cone-shape, the authors conduct the 3D dynamic finite element simulation on profile grinding with axial feed by single abrasive grain using deform-3D software. Analysis is made on the influence upon the grinding forces in case of the same grinding speed, the same grinding depth and the same friction factor between wheel and workpiece at different axial feed. The results show that the normal force and the tangential force increase with the increase of axial feed, but the axial force decreases with the axial feed.

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Actuation Torque Reduction in Parallel Robots Using Joint Compliance

Journal of Mechanisms and Robotics ◽

10.1115/1.4026628 ◽

2014 ◽

Vol 6 (2) ◽

Cited By ~ 7

Author(s):

Júlia Borràs ◽

Aaron M. Dollar

Keyword(s):

Optimization Procedure ◽

Parallel Manipulators ◽

Parallel Robots ◽

Operating Conditions ◽

Compliant Joints ◽

Force Direction ◽

Force Reduction ◽

External Forces ◽

Stewart Gough Platform ◽

Actuated Joints

This work studies in detail how the judicial application of compliance in parallel manipulators can produce manipulators that require significantly lower actuator effort within a range of desired operating conditions. We propose a framework that uses the Jacobian matrices of redundant parallel manipulators to consider the influence of compliance both in parallel with the actuated joints as well as the passive joints, greatly simplifying previous approaches. We also propose a simple optimization procedure to maximize the motor force reduction for desired regions of the workspace and range of external forces. We then apply the method to a Stewart-Gough platform and to a 3-URS (universal rotational and spherical joint) manipulator. Our results show that parallel manipulators with tasks that involve a preferred external force direction, as for instance, big weights in the platform, can see large reductions in actuator effort through the judicial use of compliant joints without significantly losing rigidity.

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Impact Analysis of Support Structure of Unsymmetrical Loading Deep Foundation Pit Adjoining Highway

The Open Civil Engineering Journal ◽

10.2174/1874149501509010463 ◽

2015 ◽

Vol 9 (1) ◽

pp. 463-470

Author(s):

Donglin Wang ◽

Lei Wang

Keyword(s):

Impact Analysis ◽

Simulation Analysis ◽

Great Influence ◽

Horizontal Displacement ◽

Friction Angle ◽

Deep Foundation ◽

Support Structure ◽

Foundation Pit ◽

Load Effect ◽

Deep Foundation Pit

The air shaft deep foundation pit 6 is influenced by subgrade unbalance loading of highway 312, specifically its deep horizontal displacement of supporting piles and subgrade settlement of expressway 312 under unsymmetrical load effect. This paper carries out construction monitoring and numerical simulation analysis and gives a detailed study on the influenced factors of support structure deformation. Calculation results show that subgrade unsymmetrical load has a great influence on deep horizontal deformation of supporting piles. The maximum horizontal displacement at the bias side is about three times more than non-bias side’s; when the distance of subgrade to foundation pit is the same as the depth of excavation, the influence of subgrade on pit can be ignored; as the cohesion and internal friction angle increases, the horizontal displacement of fender piles decreases. However, enlarging the embedded depth of supporting piles has no significant influence on the stability of foundation pit.

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Graded Origami Honeycomb Tube for Energy Absorption

Volume 5B: 43rd Mechanisms and Robotics Conference ◽

10.1115/detc2019-97898 ◽

2019 ◽

Author(s):

Leo de Waal ◽

Zhong You

Keyword(s):

Energy Absorption ◽

Honeycomb Structure ◽

Absorption Capacity ◽

Geometric Parameters ◽

Peak Force ◽

Initial Stiffness ◽

Energy Absorption Capacity ◽

Loading Process ◽

Force Increase ◽

Force Reduction

Abstract When loaded parallel to the prismatic cells (out-of-plane), honeycombs and re-entrant honeycombs exhibit high initial stiffness and peak force, followed by a force reduction as progressive failure occurs. The high initial peak force and large post-peak force reduction are undesirable for energy absorption purposes. In this study a graded honeycomb structure based on origami is proposed in an effort to lower the peak force, increase the energy absorption capacity and tune the stiffness throughout the loading process. The grading is achieved through a developable origami crease pattern that utilises the typical honeycomb expansion manufacturing technique. The crease pattern has one degree of freedom and is constructed from a repetition of a modified Miura-ori unit. A kinematic study of the crease pattern is completed, highlighting the simple geometric parameters that can be altered to tune the structure. Quasi-static numerical simulations are then used to investigate the interaction between these simple geometric parameters, the energy absorption capacity and the stiffness throughout the loading process. Compared to honeycomb and re-entrant honeycomb tubes, it has been found that a reduction in the peak force, increase in energy absorption capacity and tunable stiffness can be achieved.

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Experimental study and simulation analysis on friction behavior of a mechanical surface sliding on hard particles

Proceedings of the Institution of Mechanical Engineers Part J Journal of Engineering Tribology ◽

10.1177/1350650117693481 ◽

2017 ◽

Vol 231 (10) ◽

pp. 1371-1379 ◽

Cited By ~ 5

Author(s):

Jingjing Chang ◽

Wei Wang ◽

Ming Zhao ◽

Kun Liu

Keyword(s):

Simulation Analysis ◽

Friction Pair ◽

Granular Matter ◽

Friction Angle ◽

Experimental Results ◽

Work Piece ◽

Force Transmission ◽

Friction Behavior ◽

Hard Particles ◽

Mechanical Surface

Considering the experimental research on a mechanical surface sliding on hard particles, a friction equipment has been designed and developed to study the frictional behavior between work piece surface and granular matter. Velocity, attack angle, surface morphology, and particle size are considered in our experiments. The measured shearing force and normal force, which are transmitted by the force chain, reveals the effect of these input parameters on force transmission behavior. Results show that a rougher surface and a smaller granular size decrease the measured forces. The effects of velocity and angle of attack are discussed as well. Force transmission is directly affected by the granule–granule contact in this friction pair. The friction coefficient is dependent on the friction angle of granules and may exceed 1 here. Based on the parameter selection of experiment, simulations have been conducted to verify the experimental results by discrete element method. In this article, the direct links between the experimental results and the optimization of granular lubrication are provided.

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Analysis of Insertion Force in Elastic/Plastic Mating

Journal of Electronic Packaging ◽

10.1115/1.2904366 ◽

1990 ◽

Vol 112 (3) ◽

pp. 192-197 ◽

Cited By ~ 2

Author(s):

S. E. Yamada ◽

H. Ueno

Keyword(s):

Contact Force ◽

Contact Point ◽

Friction Angle ◽

Electronic System ◽

Insertion Force ◽

Elastic Plastic ◽

Contact Points ◽

Force Direction ◽

System Interconnection ◽

Insertion Process

A simulation of an insertion of a solid pin into a slot between two opposing compliant beams is attempted. As a particular feature, the elastic-plastic deformation of the slot during the insertion is incorporated, as such a situation often occurs in electronic system interconnection. Each instance of the insertion process is considered as a static equilibrium of the insertion force and the contact force (including the frictional force). The equilibrium position of the deflected beams and the pin can be obtained as the point satisfying the following two conditions: 1) at the contact point, the contact force direction is offset from the normal direction to the contact points by the friction angle and, 2) the present positions of the contact points (one on the beam and the other on the pin), and their tangent angles must coincide exactly with each other. The simulated insertion force and depth relation agrees well with the real measurement.

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Numerical Simulation Study on Influence Factors of the Filling Body Stability in Partial-Filling Mining

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.522-524.1403 ◽

2014 ◽

Vol 522-524 ◽

pp. 1403-1409

Author(s):

Zhong Ping Guo ◽

Wan Peng Huang ◽

Fan Feng ◽

Sha Sha Yan ◽

Chun Han

Keyword(s):

Numerical Simulation ◽

Simulation Analysis ◽

Influence Factors ◽

Friction Angle ◽

Power Exponent ◽

Filling Rate ◽

Plasticity Zone ◽

Deep Mine ◽

Working Face ◽

Partial Filling

There are many factors that influence filling body stability in partial-filling mining. In deep mining, filling rate and internal friction angle of filling body are the main factors that greatly influence both sides of plasticity zone breadth in the process of filling bodys deformation and destruction. Taking filling rate and friction angle as the main variables to make a numerical simulation analysis on the deep mine working face, we can find a conclusion that it shows a concave-down power exponent relationship between the width of plasticity zone and the filling rate; With lower filling rate, it shows a concave-up power exponent relationship with friction angle, and the relationship of power exponent will change into the linearity as the filling rate increase.

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