Compliances of Basic Flexible-Hinge Segments

2020 ◽  
pp. 9-71
Author(s):  
Nicolae Lobontiu
Keyword(s):  
Flexible Hinge

scholarly journals Spatial Restrictions in Chemotaxis Signaling Arrays: A Role for Chemoreceptor Flexible Hinges across Bacterial Diversity

2019 ◽  
Vol 20 (12) ◽  
pp. 2989 ◽  
Author(s):  
David Stalla ◽  
Narahari Akkaladevi ◽  
Tommi White ◽  
Gerald Hazelbauer
Keyword(s):  
Escherichia Coli ◽  
Bacterial Diversity ◽  
Crucial Role ◽  
Geometric Analysis ◽  
Sensory System ◽  
Molecular Crowding ◽  
Flexible Hinge ◽  
Dynamic Variation ◽  
Close Proximity ◽  
Bend Angles

The chemotactic sensory system enables motile bacteria to move toward favorable environments. Throughout bacterial diversity, the chemoreceptors that mediate chemotaxis are clustered into densely packed arrays of signaling complexes. In these arrays, rod-shaped receptors are in close proximity, resulting in limited options for orientations. A recent geometric analysis of these limitations in Escherichia coli, using published dimensions and angles, revealed that in this species, straight chemoreceptors would not fit into the available space, but receptors bent at one or both of the recently-documented flexible hinges would fit, albeit over a narrow window of shallow bend angles. We have now expanded our geometric analysis to consider variations in receptor length, orientation and placement, and thus to species in which those parameters are known to be, or might be, different, as well as to the possibility of dynamic variation in those parameters. The results identified significant limitations on the allowed combinations of chemoreceptor dimensions, orientations and placement. For most combinations, these limitations excluded straight chemoreceptors, but allowed receptors bent at a flexible hinge. Thus, our analysis identifies across bacterial diversity a crucial role for chemoreceptor flexible hinges, in accommodating the limitations of molecular crowding in chemotaxis core signaling complexes and their arrays.

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.

Microsurgical Devices by Pop-Up Book MEMS

2013 ◽  
Author(s):  
Joshua B. Gafford ◽  
Samuel B. Kesner ◽  
Robert J. Wood ◽  
Conor J. Walsh
Keyword(s):  
Lap Joints ◽  
Small Scale ◽  
Flexible Hinge ◽  
Final Weight ◽  
Out Of Plane ◽  
Return Spring ◽  
Torsional Loads ◽  
Manufacturing Techniques ◽  
Traditional Manufacturing ◽  
Electrical Components

The small scale of microsurgery poses significant challenges for developing robust and dexterous tools to grip, cut, and join sub-millimeter structures such as vessels and nerves. The main limitation is that traditional manufacturing techniques are not optimized to create smart, articulating structures in the 0.1–10 mm scale. Pop-up book MEMS is a new fabrication technology that promises to overcome this challenge and enable the monolithic fabrication of complex, articulated structures with an extensive catalog of materials, embedded electrical components, and automated assembly with feature sizes down to 20 microns. In this paper, we demonstrate a proof-of-concept microsurgical gripper and evaluate its performance at the component and device level to characterize its strength and robustness. 1-DOF Flexible hinge joints that constrain motion and allow for out-of-plane actuation were found to resist torsional loads of 22.8±2.15 N·mm per mm of hinge width. Adhesive lap joints that join individual layers in the laminate structure demonstrated a shear strength of 26.8±0.53 N/mm2. The laminate structures were also shown to resist peel loads of 0.72±0.10 N/mm2. Various flexible hinge and adhesive lap components were then designed into an 11-layered structure which ‘pops up’ to realize an articulating microsurgical gripper that includes a cable-driven mechanism for gripping actuation and a flexural return spring to passively open the gripper. The gripper prototype, with final weight of 200 mg, overall footprint of 18 mm by 7.5 mm, and features as small as 200 microns, is able to deftly manipulate objects 100 times is own weight at the required scale, thus demonstrating its potential for use in microsurgery.

Flexible hinge toe implant arthroplasty for rheumatoid arthritis of the first metatarsophalangeal joint: long-term results

2001 ◽  
Vol 6 (2) ◽  
pp. 141-147 ◽  
Author(s):  
Tadamasa Hanyu ◽  
Hideshi Yamazaki ◽  
Hajime Ishikawa ◽  
Katsumitsu Arai ◽  
Chikako T. Tohyama ◽  
...  
Keyword(s):  
Rheumatoid Arthritis ◽  
Metatarsophalangeal Joint ◽  
Long Term Results ◽  
First Metatarsophalangeal Joint ◽  
Flexible Hinge
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