A Robot for Cell Injection

2013 ◽  
Vol 3 (3) ◽  
pp. 77-98 ◽  
Author(s):  
K. Kostadinov ◽  
D. Chakarov ◽  
A. Shulev ◽  
T. Tiankov
Keyword(s):  
Numerical Evaluation ◽  
Parallel Robot ◽  
Parallel Structure ◽  
Correlation Technique ◽  
Mechanical Parameters ◽  
Biological Cells ◽  
Element Analysis ◽  
Cell Injection ◽  
Stiffness Model ◽  
Set Up

This work deals with modelling and experimenting of a compliant serial-parallel robot. Using Pseudo-Rigid-Body Modelling (PRBM) of elastic structures, a kinematics and stiffness model of a serial-parallel structure has been built. Several approaches for pre-tensioning of a parallel structure with elastic joints were developed in order to eliminate backlashes and improve the performance of its actuators. In this work a robot is designed to inject biological cells with size in the range of 10-30µm. The approaches used for pre-tensioning of the robot have been analysed and subjected to numerical evaluation. Assessing the mechanical parameters of the tensed manipulator has been performed using the following methods: PRBM and Finite Element Analysis (FEA). An experimental set-up for testing a robot prototype has been developed, using an optical system and correlation technique for digital image processing. The experimental results obtained are compared to data received from the numerical experiment.

The Analyse on Stiffness Model of 3-PPSR Flexible Parallel Robot

2014 ◽  
Vol 716-717 ◽  
pp. 1643-1647
Author(s):  
Yu Liang Luan ◽  
Wei Bin Rong ◽  
Li Ning Sun
Keyword(s):  
Finite Element ◽  
Aspect Ratio ◽  
High Aspect Ratio ◽  
Parallel Robot ◽  
Force Balance ◽  
Element Analysis ◽  
Flexible Hinge ◽  
Stiffness Model ◽  
The Finite Element Analysis ◽  
The Mathematical Model

In order to achieve greater workspace motion, it’s designed a high aspect ratio 3-PPSR flexible parallel robot, driven by a piezoelectric motor, connected by flexible hinges, which has the advantages of simple structure, non singular, seamless, high motion precision. Because of the stiffness of the system directly affecting the motion accuracy, load bearing performance, according to the characteristics of high aspect ratio flexible hinge, It’s established the mathematical model of flexible hinge through finite element method. Using method of integral stiffness, conbined coordination equation with force balance equation, the flexible stiffness model of system is obtained. Finally, through using Ansys, it’s confirmed the validity of the theoretical model by comparing of the theoretical stiffness model results with the finite element analysis of the model results, to provide a reliable guarantee for optimization and analysis of kinematics and dynamics of flexible parallel robot.

Dynamics Simulation Analysis of Flexible Multibody of Parallel Robot

2007 ◽  
Vol 10-12 ◽  
pp. 647-651 ◽  
Author(s):  
C.X. Zhu ◽  
Yong Xian Liu ◽  
Guang Qi Cai ◽  
L.D. Zhu
Keyword(s):  
Simulation Analysis ◽  
Parallel Robot ◽  
Rigid Bodies ◽  
Simulation Software ◽  
Dynamics Simulation ◽  
Element Analysis ◽  
Flexible Multibody ◽  
Simulation Results ◽  
Set Up ◽  
Parallel Machine Tool

Take a kind of 3-TPT parallel robot as an example, the model of flexible multibody of parallel machine tool is built by using multibody dynamics simulation software ADAMS and finite element analysis software ANSYS. And dynamics equation of flexible body in spatial is also set up, after that the dynamics simulation is carried out. Then the simulation results of rigid bodies are compared with flexible ones, and the results show that the forces applied on flexible bodies appear high nonlinear, so the simulation results of flexible multibody system are more authentic, nicety and can reflect actual dynamics characteristic of parallel robot.

scholarly journals The Effect of Transversal Connection in the in-Plane Response of Double-Leaf Brick Masonry Walls

2021 ◽  
Author(s):  
Lorenzo Scandolo ◽  
Stefano Podestà
Keyword(s):  
Structural Safety ◽  
Masonry Walls ◽  
Masonry Building ◽  
Mechanical Parameters ◽  
Compression Tests ◽  
Knowledge Process ◽  
Diagonal Compression ◽  
Set Up ◽  
Definition Of ◽  
Simplified Mechanical Model

Abstract The evaluation of structural safety derives from the knowledge of material properties. In case of existent masonry building, the definition of reliable mechanical parameters could be a very difficult task to be achieved. For this reason, an estimation of these values is useful, for example it is the first phase of the knowledge process, for simplified mechanical model or when NTD test is the only possibility.The transversal connection in masonry panels is a technological detail that affects the static and seismic behavior and could significantly increase the strength of the element.In this paper the effect of transversal connection in double-leaf brickwork masonry panels is evaluated by diagonal compression tests. To achieve this goal, a new set-up was designed to load each leaf independently.The results have shown an increment of about 20% in strength if transversal connection is present. If the leaves have very different mechanical parameters, the tests highlight an unexpected behavior.

Determination of mechanical parameters for rotating MEMS structures as a function of deposition method

2003 ◽  
Vol 795 ◽  
Author(s):  
S. Soare ◽  
S. J. Bull ◽  
A. Oila ◽  
A. G. O'Neill ◽  
N. Wright ◽  
...  
Keyword(s):  
Creep Behaviour ◽  
Peak Load ◽  
Mechanical Parameters ◽  
Deposition Method ◽  
Element Analysis ◽  
Microelectronic Devices ◽  
Micro Sensor ◽  
Geometrical Dimensions ◽  
Modelling Data

ABSTRACTThe dimensions of microelectronic devices are constantly being reduced due to the increasing operational demands imposed such as higher working frequencies, higher component density and lower power consumption. This affects the geometrical dimensions of the metallisation, i.e. its width and thickness. The mechanical properties of very thin films are considerably different from those of bulk materials and, also, the deposition method may influence the mechanical behaviour of the components. In order to obtain reliable metallisation it is therefore important to assess accurately the mechanical parameters of the interconnecting lines. As part of designing, developing and manufacturing of a stress micro-sensor there is a need to extract properties useful for performance prediction such as yield stress or creep relaxation behaviour. Part of the data may be obtained by nanoindentation but to have a more complete view, finite element analysis of the indentation cycle has to be employed. In this study nanoindentation testing was carried out at various depths on sputtered and evaporated aluminium layers with different thicknesses deposited on (100) silicon. The loading curves were then simulated by FEA and the results compared to identify the yield properties of the coating. Modelling data for thicker samples closely follows experimental data but for thinner coatings there is a considerable gradient in properties through the film thickness. By incorporating a peak load hold the creep behaviour of the metallization can also be assessed and modelling parameters developed.

Testing and Modeling of Mechanical Parameters in Resistance Welding Machines

2013 ◽  
Vol 712-715 ◽  
pp. 1235-1240
Author(s):  
Pei Wu ◽  
Yong An Zhang ◽  
Chuan Zhong Xuan ◽  
Yan Hua Ma
Keyword(s):  
Mechanical Response ◽  
Resistance Welding ◽  
Work Piece ◽  
Mechanical Parameters ◽  
Test Set ◽  
Dynamic Mechanical ◽  
Projection Welding ◽  
Welding Machine ◽  
Equivalent Mass ◽  
Set Up

The dynamic mechanical responses of resistance welding machine,which is mainly governed by the mechanical parameters of the machine, is very important to the weld quality especially in projection welding when collapse or deformation of work piece occurs. In this paper, a mathematical model for characterizing the dynamic mechanical response of resistance welding machine and a special test set-up called breaking test set-up have been developed. Based on the model and the test results, the mechanical parameters of the machine were identified, including the equivalent mass, the damping coefficient, and the stiffness for both electrode systems.

A Method for Compliance Modeling of Five Degree-of-Freedom Overconstrained Parallel Robotic Mechanisms With 3T2R Output Motion

2016 ◽  
Vol 9 (1) ◽  
Author(s):  
Wen-ao Cao ◽  
Huafeng Ding ◽  
Donghao Yang
Keyword(s):  
Screw Theory ◽  
Parallel Manipulators ◽  
Static Equilibrium ◽  
Equilibrium Equations ◽  
Element Analysis ◽  
Compliance Matrix ◽  
Fea Model ◽  
Stiffness Model ◽  
Compliance Modeling ◽  
The One

This paper presents an approach to compliance modeling of three-translation and two-rotation (3T2R) overconstrained parallel manipulators, especially for those with multilink and multijoint limbs. The expressions of applied wrenches (forces/torques) exerted on joints are solved with few static equilibrium equations based on screw theory. A systematic method is proposed for deriving the stiffness model of a limb with considering the couplings between the stiffness along the constrained wrench and the one along the actuated wrench based on strain energy analysis. The compliance model of a 3T2R overconstrained parallel mechanism is established based on stiffness models of limbs and the static equilibrium equation of the moving platform. Comparisons show that the compliance matrix obtained from the method is close to the one obtained from a finite-element analysis (FEA) model. The proposed method has the characteristics of involving low computational efforts and considering stiffness couplings of each limb.

Elastic Contact Model Accounting for Both Asperity and Substrate Compliance With Application to Patterned Media

2007 ◽  
Author(s):  
Chang-Dong Yeo ◽  
Andreas A. Polycarpou
Keyword(s):  
Bulk Material ◽  
Contact Stiffness ◽  
Contact Model ◽  
Elastic Contact ◽  
Element Analysis ◽  
Patterned Media ◽  
Single Asperity ◽  
Proposed Model ◽  
Stiffness Model ◽  
Bulk Substrate

An improved elastic contact stiffness model for a single asperity system is proposed to account for the effects of both bulk substrate and asperity deformations between two contacting surfaces. Depending upon the applied load, as well as the geometrical and physical properties of the asperity and bulk material, the bulk substrate can have a considerable contribution to the overall contact stiffness. Finite element analysis is performed to verify the proposed analytical model. The single asperity model is extended to rough surfaces in contact. The contact stiffness values from the proposed model are compared to those from the GW model. The proposed contact model can be directly relevant to analyze the contact behavior of modern patterned media.

Use of Tracer Particles for Tracking Fluid Interfaces in Primary Cementing

2019 ◽  
Author(s):  
Amir Taheri ◽  
Jan David Ytrehus ◽  
Ali Taghipour ◽  
Bjørnar Lund ◽  
Alexandre Lavrov ◽  
...  
Keyword(s):  
Numerical Models ◽  
Secondary Flows ◽  
Equivalent Model ◽  
Fluid Interfaces ◽  
Element Analysis ◽  
Two Fluids ◽  
Tracer Particles ◽  
Narrow Side ◽  
Primary Cementing ◽  
Set Up

Abstract In this study, a new approach for detailed tracking of the interface between well fluid and cement by using particles is investigated. This can improve the quality of annular cementing of CO2 wells and thus the storage safety. For this purpose, the displacement mechanisms of Newtonian and non-Newtonian fluids in the annulus of vertical and inclined wells is investigated by using an experimental set-up with an eccentric annular geometry and by finite element analysis of an equivalent model with COMSOL Multiphysics solver. For more efficient displacement, the displacing fluid has a higher density than the displaced fluid, and the intermediate-buoyancy particles that reside at the interface between successive fluids are introduced into the models. Such particles must overcome strong secondary flows in order to travel with the interface. Particle motions are investigated in different experimental and numerical models, and their effectiveness is investigated. The experimental results confirm that while the particles with a size of 425–500 um are unable to overcome the secondary flows in eccentric vertical models and track the interface, they can be useful for tracking the interface between two fluids in an eccentric model with a small inclination to the narrow side. CFD analysis investigates this behavior with more details and shows the effects of some parameters on the particle motions.

scholarly journals Inflation and rupture of vaginal tissue

2019 ◽  
Vol 9 (4) ◽  
pp. 20190029 ◽  
Author(s):  
Jeffrey A. McGuire ◽  
Christie L. Crandall ◽  
Steven D. Abramowitch ◽  
Raffaella De Vita
Keyword(s):  
Axial Direction ◽  
Image Correlation ◽  
Correlation Technique ◽  
Vaginal Tissue ◽  
Free Extension ◽  
Incorrect Diagnosis ◽  
Failure Properties ◽  
Set Up ◽  
Term Baby ◽  
Hoop Direction

Around 80% of women experience vaginal tears during labour when the diameter of the vagina must increase to allow the passage of a full-term baby. Current techniques for evaluating vaginal tears are qualitative and often lead to an incorrect diagnosis and inadequate treatment, severely compromising the quality of life of women. In order to characterize the failure properties of the vaginal tissue, whole vaginal tracts from rats ( n = 18) were subjected to free-extension inflation tests until rupture using a custom-built experimental set-up. The resulting deformations were measured using the digital image correlation technique. Overall, the strain and changes in curvature in the hoop direction were significantly larger relative to the axial direction. At a failure pressure of 110 ± 23 kPa (mean ± s.d.), the hoop and axial stresses were computed to be 970 ± 340 kPa and 490 ± 170 kPa, respectively. Moreover, at such pressure, the hoop and axial strains were found to be 12.8 ± 4.4 % and 6.4 ± 3.7 % , respectively. Rupture of the vaginal specimens always occurred in the hoop direction by tearing along the axial direction. This knowledge about the rupture properties of the vaginal tissue will be crucial for the development of clinical approaches for preventing and mitigating vaginal tearing and the associated short- and long-term traumatic conditions.

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