scholarly journals Micromanipulation System for Isolating a Single Cryptosporidium Oocyst

Micromachines ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 3 ◽  
Author(s):  
Hamish Penny ◽  
David T. S. Hayman ◽  
Ebubekir Avci
Keyword(s):  
Single Cell Analysis ◽  
Cryptosporidium Oocyst ◽  
Integrated System ◽  
Adhesion Forces ◽  
Automated Control ◽  
Liquid Environment ◽  
End Effector ◽  
3D Space ◽  
Contact Adhesion ◽  
Automated Alignment

In this paper, an integrated system for contact micromanipulation of Cryptosporidium oocysts is presented. The system integrates five actuators and a partially automated control system and contacts the oocyst using a drawn glass end effector with tip dimensions of 1 μ m. The system is intended to allow single cell analysis (SCA) of Cryptosporidium—a very harmful parasite found in water supplies—by isolating the parasite oocyst of 5 μ m diameter in a new environment. By allowing this form of analysis, the source of Cryptosporidium can be found and potential harm to humans can be reduced. The system must overcome the challenges of locating the oocysts and end effector in 3D space and contact adhesion forces between them, which are prominent over inertial forces on this scale. An automated alignment method is presented, using the Prewitt operator to give feedback on the level of focus and this system is tested, demonstrating alignment accuracy of <2 μ m. Moreover, to overcome the challenge of adhesion forces, use of dry and liquid environments are investigated and a strategy is developed to capture the oocyst in the dry environment and release in the liquid environment. An experiment is conducted on the reliability of the system for isolating a Cryptosporidium oocyst from its culture, demonstrating a success rate of 98%.

Fuzzy Logic Control for an Integrated System of a Micro-Manipulator with a Single Flexible Beam

2004 ◽  
Vol 10 (5) ◽  
pp. 755-776 ◽  
Author(s):  
N. G. Chalhoub ◽  
B. A. Bazzi
Keyword(s):  
Fuzzy Logic ◽  
Fuzzy Logic Controller ◽  
Angular Displacement ◽  
Digital Simulation ◽  
Linear Quadratic Regulator ◽  
Integrated System ◽  
Flexible Beam ◽  
Linear Quadratic ◽  
End Effector ◽  
Micro Manipulator

The use of lightweight robotic manipulators in advanced assembly and manufacturing applications is hindered by the end-effector positional inaccuracies induced by the structural deformations of the arm. To address this problem, a macro- and micro-manipulator system is considered herein. Three rigid and flexible motion controllers, consisting of an integral plus state feedback controller (ISFC), linear quadratic regulator with an integral action (LQI) and a fuzzy logic controller (FLC), have been implemented in this study. The performances of these controllers are compared based on achieving zero steady-state error in the rigid body angular displacement of the beam, damping out the unwanted vibrations, rendering the end-effector insensitive to the vibrations of the arm, and avoiding excessive control torque requirements. The digital simulation results demonstrate the superiority of the FLC over the ISFC and LQI in damping out the vibrations of the beam and reducing the gripper positional inaccuracies while requiring relatively smaller control torques. Furthermore, the results clearly demonstrate the robustness of the FLC to significant variations in the payload mass.

scholarly journals FRICTION AND ADHESION OF MONOMOLECULAR COATINGS

2017 ◽  
Author(s):  
I.N. Kavaliova ◽  
E.A. Kovalev ◽  
A.Ya. Grigoriev
Keyword(s):  
Wear Resistance ◽  
Coefficient Of Friction ◽  
Acid Ester ◽  
Experimental Results ◽  
Silicon Substrates ◽  
Adhesion Forces ◽  
Silicon Plate ◽  
Monomolecular Films ◽  
Contact Adhesion

The paper presents data on measurements of friction and adhesion forces of silicon ball and silicon plate covered by DDPO4 (dodecylphosphoric acid ester), ODPO4 (octadecylphosphoric acid ester), SEBS (poly[styrene-b-(ethylene-co-butylene)-b-styrene]) and OTS (octadecyltrichlorsilane) and others. Tests were performed with reciprocating microtribometer and contact adhesion meter. The experimental results have shown, that coefficient of friction, between a silicon ball and silicon substrates modified by the monomolecular films, are varied in the range 0.05…0.25, with wear-resistance from 20 to 2000 cycles. An ambiguous correlation was found between friction and contact adhesion forces of investigated surfaces.

scholarly journals Algorithm to obtain inverse kinematics matrix from the 3D curve and to apply to glue shoe sole

2014 ◽  
Vol 17 (2) ◽  
pp. 5-17
Author(s):  
Thanh Le Nhu Ngoc Ha ◽  
Tung Thanh Luu ◽  
Tien Tan Nguyen
Keyword(s):  
Pid Controller ◽  
Inverse Kinematics ◽  
Interpolation Method ◽  
Industrial Applications ◽  
Tracking Performance ◽  
End Effector ◽  
Reference Path ◽  
3D Space ◽  
Position And Orientation ◽  
Arbitrary Curve

Nowadays, manipulator is widely used in industrial applications. The trajectories of manipulator are more and more complicated. In order to do good tracking performance, the end effector position and orientation have to be determined. This paper describes a method to determine position and orientation of manipulator’s end effector base on a reference path. This method will be applied for manipulator 6 DOF to glue shoe sole. Firstly, assume the reference path is arbitrary curve, the path was then discrete to become multi-point. Secondly, the roll – pitch – yaw vectors of the end effector will be determined at each point. Finally, Euler angles and interpolation method in 3D space will be applied to determine inverse kinematics matrix of manipulator for each point on the reference path. In addition, this paper also gives an example of reference path of shoe sole to apply the presented method. To verify the tracking performance of manipulator and reference path, a PID controller was designed for simulation. The result of simulation proved the correction of the algorithm.

scholarly journals ATOMIC FORCE MICROSCOPY MEASUREMENTS OF BOVINE SERUM ALBUMIN ADHESION FORCES ON SURFACES

2008 ◽  
Vol 07 (06) ◽  
pp. 299-303 ◽  
Author(s):  
CHUN-CHIH LAI ◽  
NUNZIO MOTTA ◽  
JOHN M. BELL
Keyword(s):  
Atomic Force Microscopy ◽  
Bovine Serum Albumin ◽  
Serum Albumin ◽  
Bovine Serum ◽  
Hydrophobic Surface ◽  
Adhesion Forces ◽  
Liquid Environment ◽  
Force Microscopy ◽  
Atomic Force ◽  
Direct Technique

A novel, direct technique has been developed to measure the interactions of bovine serum albumin (BSA) on surfaces by using atomic force microscopy (AFM) in a liquid environment. We have been able to measure adhesion forces between proteins and substrate surfaces in phosphate-buffered saline (PBS) solution directly, without any modification to the substrate and the AFM tip. Two different surfaces have been used in the measurements: mica (hydrophilic surface) and polystyrene (hydrophobic surface). The results show that a polystyrene surface has larger adhesion forces to BSA than a mica surface. This is consistent with previous research, which demonstrated that hydrophobic surfaces enhance protein adhesion but hydrophilic surfaces do not.

Robotic handling and packaging of poultry products

Robotica ◽  
1990 ◽  
Vol 8 (4) ◽  
pp. 285-297 ◽  
Author(s):  
K. Khodabandehloo
Keyword(s):  
Machine Vision ◽  
Research Programme ◽  
Automatic Recognition ◽  
Robotic System ◽  
Integrated System ◽  
System Software ◽  
End Effector ◽  
Poultry Products ◽  
Industrial Use ◽  
Vision Module

SUMMARYThis paper presents the findings of a research programme leading to the development of a robotic system for packaging poultry portions. The results show that an integrated system, incorporating machine vision and robots, can be made feasible for industrial use. The elements of this system, including the end-effector, the vision module, the robot hardware and the system software are presented. Models and algorithms for automatic recognition and handling of poultry portions are discussed.

scholarly journals Force-induced changes of PilY1 drive surface sensing by Pseudomonas aeruginosa

2021 ◽  
Author(s):  
Shanice Webster ◽  
Marion Mathelie-Guinlet ◽  
Andreia Verissimo ◽  
Daniel Schultz ◽  
Albertus Viljoen ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Conformational Changes ◽  
Biofilm Formation ◽  
Single Cell Analysis ◽  
Opportunistic Pathogen ◽  
Lower Surface ◽  
Cysteine Residue ◽  
Adhesion Forces ◽  
Surface Sensing ◽  
Induced Changes

During biofilm formation, the opportunistic pathogen Pseudomonas aeruginosa uses its type IV pili (TFP) to sense a surface, eliciting increased second messenger production and regulating target pathways required to adapt to a surface lifestyle. The mechanisms whereby TFP detect surface contact is still poorly understood, although mechanosensing is often invoked with little data supporting this claim. Using a combination of molecular genetics and single cell analysis, with biophysical, biochemical and genomics techniques we show that force-induced changes mediated by the von Willebrand A (vWA) domain-containing, TFP tip-associated protein PilY1 are required for surface sensing. Atomic force microscopy shows that PilY1 can undergo force induced, sustained conformational changes akin to those observed for mechanosensitive proteins like titin. We show that mutation of a single cysteine residue in the vWA domain results in modestly lower surface adhesion forces, increased nanospring-like properties, as well as reduced c-di-GMP signaling and biofilm formation. Mutating this cysteine has allowed us to genetically separate TFP function in twitching from surface sensing signaling. The conservation of this Cys residue in all P. aeruginosa PA14 strains, and its absence in the ~720 sequenced strains of P. aeruginosa PAO1, could contribute to explaining the observed differences in surface colonization strategies observed for PA14 versus PAO1.

The three-dimensional structure of frozen-hydrated left- and right-handed forms of bacterial flagellar filaments from an identical serotype

1986 ◽  
Vol 44 ◽  
pp. 298-299
Author(s):  
S. Trachtenberg ◽  
D. J. DeRosier
Keyword(s):  
Ionic Strength ◽  
Basal Body ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Protein Species ◽  
Liquid Environment ◽  
Bacterial Flagellum ◽  
Left And Right ◽  
Rotary Motor ◽  
Helical Parameters

The bacterial cell is propelled through the liquid environment by means of one or more rotating flagella. The bacterial flagellum is composed of a basal body (rotary motor), hook (universal coupler), and filament (propellor). The filament is a rigid helical assembly of only one protein species — flagellin. The filament can adopt different morphologies and change, reversibly, its helical parameters (pitch and hand) as a function of mechanical stress and chemical changes (pH, ionic strength) in the environment.

Beam-radiation effects on wool in the ESEM

1986 ◽  
Vol 44 ◽  
pp. 674-675
Author(s):  
G.D. Danilatos
Keyword(s):  
Electron Beam ◽  
Radiation Effects ◽  
Research Work ◽  
Beam Radiation ◽  
Liquid Environment ◽  
Know How ◽  
Environmental Sem

The advent of the environmental SEM (ESEM) has made possible the examination of uncoated and untreated specimen surfaces in the presence of a gaseous or liquid environment. However, the question arises as to what degree the examined surface remains unaffected by the action of the electron beam. It is reasonable to assume that the beam invariably affects all specimens but the type and degree of effect may be totally unimportant for one class of applications and totally unacceptable for another; yet, for a third class, it is imperative to know how our observations are modified by the presence of the beam. The aim of this report is to create an awareness of the need to initiate research work in various fields in order to determine the guiding rules of the limitations (or even advantages) due to irradiation.

Sign in / Sign up

Export Citation Format

Share Document