Optimal Design of Compliant Joint and Gripper for Miniature Robotic Devices: Application to Surgery

2012 ◽  
Author(s):  
Christine Rotinat-Libersa ◽  
Belen Solano
Keyword(s):  
Synthesis Method ◽  
Building Blocks ◽  
Output Displacement ◽  
Actuation Force ◽  
Compliant Joint ◽  
Limited Output ◽  
Robotic Devices ◽  
Mechanical Performances ◽  
Gripping Force ◽  
Large Output

In this paper, we present the different steps towards the development of miniature compliant bending joint and gripper with high mechanical performances. These low encumbrance structures (5 mm cross-section) should deliver, with few actuation force, a large output displacement (90° bending, and 60° jaws opening respectively) under large output loads. Firstly, we describe the theoretical studies that have been investigated in order to optimally dimension these structures. For the bending joint, the design has been inspired from the literature and optimized. For the gripper, a non-intuitive design has been generated using a multi-objective optimal synthesis method. Finally, these compliant structures have been prototyped, and characterized. As an applicative example, they have been integrated into the end-effector of a surgical instrument. Despite the limited output load performances obtained (12.5 mN.m output torque with a 2.1 N actuation force, and 0.2 N gripping force respectively), these new building blocks demonstrate the ability of millimeter-size robotic devices further miniaturization.

Applying Rigidity Theory Methods for Topological Decomposition and Synthesis of Gear Train Systems

2012 ◽  
Author(s):  
Maria Terushkin ◽  
Offer Shai
Keyword(s):  
Synthesis Method ◽  
Building Blocks ◽  
The Body ◽  
Computational Method ◽  
Gear Train ◽  
Graph Representation ◽  
Rigidity Theory ◽  
Graph Representations ◽  
Machine Theory ◽  
Gear Trains

This paper introduces a novel way to augment the knowledge and methods of rigidity theory to the topological decomposition and synthesis of gear train systems. A graph of gear trains, widely reported in the literature of machine theory, is treated as a graph representation from rigidity theory—the Body-Bar graph. Once we have this Body-Bar graph, methods and theorems from rigidity theory can be employed for analysis and synthesis. In this paper we employ the pebble-game algorithm, a computational method which allows determination of the topological mobility of mechanisms and the decomposition of gear trains into basic building blocks—Body-Bar Assur Graphs. Once we gain the ability to decompose any gear train into standalone components (Body-Bar Assur Graphs), this paper suggests inverting the process and applying the same method for synthesis. Relying on rigidity theory operations (Body-Bar extension, in this case), it is possible to construct all of the Body-Bar Assur Graphs, meaning the building blocks of gear trains. Once we have these building blocks at hand, it is possible to recombine them in various ways, providing us with a topological synthesis method for constructing gear trains. This paper also introduces a transformation between the Body-Bar graph and other graph representations used in mechanisms, thus leaving room for the application of the proposed synthesis and decomposition method directly to known graph representations already used in machine theory.

Straight-Line Mechanisms as One Building Element of Small Precise Robotic Devices

2014 ◽  
Vol 613 ◽  
pp. 96-101 ◽  
Author(s):  
Jaroslav Hricko
Keyword(s):  
Compliant Mechanisms ◽  
Building Blocks ◽  
Linear Motion ◽  
Kinematics Analysis ◽  
Positioning Accuracy ◽  
Building Element ◽  
Revolute Joints ◽  
Straight Line ◽  
Robotic Devices ◽  
Straight Line Mechanism

Small precise robotic devices, working on principle of compact compliant mechanisms, must meet the conditions to high positioning accuracy what mean moving in straight-line too. But, compliant mechanisms are usually produced by equivalent of revolute joints, therefore in design of small robotic devices is necessary apply knowledge from design of one type of specialized mechanisms – straight-line mechanisms. This paper presents some straight-line mechanism and its applications to design of some small precise robotic devices. According to kinematics analysis most known straight-line mechanisms are evaluated for their application in compliant mechanisms. Such devices are transformed to flexure structures. Consequently, these devices are important building blocks to design some linear-motion stages and/or micro-grippers.

scholarly journals Inhibition of the urea-urease reaction by the components of the zeolite imidazole frameworks-8 and the formation of urease-zinc-imidazole hybrid compound

2022 ◽  
Author(s):  
Norbert Német ◽  
Ylenia Miele ◽  
Gábor Shuszter ◽  
Eszter L. Tóth ◽  
János Endre Maróti ◽  
...  
Keyword(s):  
Self Assembly ◽  
Enzymatic Reaction ◽  
Synthesis Method ◽  
Material Design ◽  
Building Blocks ◽  
Zinc Ions ◽  
Material Synthesis ◽  
Hybrid Compound ◽  
Inhibition Effect ◽  
Metal Organic

AbstractIn the past decade, much effort has been devoted to using chemical clock-type reactions in material design and driving the self-assembly of various building blocks. Urea-urease enzymatic reaction has chemical pH clock behavior in an unbuffered medium, in which the induction time and the final pH can be programmed by the concentrations of the reagents. The urea-urease reaction can offer a new alternative in material synthesis, where the pH and its course in time are crucial factors in the synthesis. However, before using it in any synthesis method, it is important to investigate the possible effects of the reagents on the enzymatic reaction. Here we investigate the effect of the reagents of the zeolite imidazole framework-8 (zinc ions and 2-methylimidazole) on the urea-urease reaction. We have chosen the zeolite imidazole framework-8 because its formation serves as a model reaction for the formation of other metal–organic frameworks. We found that, besides the inhibition effect of the zinc ions which is well-known in the literature, 2-methylimidazole inhibits the enzymatic reaction as well. In addition to the observed inhibition effect, we report the formation of a hybrid urease-zinc-2-methylimidazole hybrid material. To support the inhibition effect, we developed a kinetic model which reproduced qualitatively the experimentally observed kinetic curves.

THE SYNTHESIS OF MECHANISM SYSTEMS USING A MECHANISM CONCEPT LIBRARY

2010 ◽  
Vol 34 (1) ◽  
pp. 151-163 ◽  
Author(s):  
Feng-Ming Ou ◽  
Hong-Sen Yan ◽  
Ming-Feng Tang
Keyword(s):  
Synthesis Method ◽  
Building Blocks ◽  
Graph Representation ◽  
Synthesis Approach ◽  
Synthesis Of Mechanism

This paper presents an approach for synthesizing all possible mechanism systems of kinematic building blocks in a mechanism concept library. The kinematic building blocks are defined as SISO primitive mechanisms, and their serial and/or parallel combinations are expressed as corresponding out-trees based on graph representation. By representing the constructive building blocks as labeled vertices and their possible combination relationships as directed edges, the synthesis approach is developed by adopting graph enumeration theorem. An illustrative example of four kinematic building blocks, including two crank-rocker linkages and two slider-crank mechanisms, is provided to validate the presented approach. The result shows that all feasible mechanism systems can be obtained effectively by following the synthesis method and which provides more alternatives in the library during design or re-design of mechanisms.

Engineered metal–oxide–metal heterojunction nanowires

2005 ◽  
Vol 20 (10) ◽  
pp. 2613-2617 ◽  
Author(s):  
Jason S. Tresback ◽  
Alexander L. Vasiliev ◽  
Nitin P. Padture
Keyword(s):  
Metal Oxide ◽  
Selective Oxidation ◽  
Functional Properties ◽  
Synthesis Method ◽  
Building Blocks ◽  
Synthesis Methods ◽  
Unique Combination ◽  
Heterojunction Structure ◽  
Rare Opportunity

Using a unique combination of template-based synthesis methods involving anodization, electroplating, and selective oxidation, we have synthesized engineered metal–oxide–metal (MOM) heterojunction nanowires in the Au–SnO2–Au and Au–NiO–Au systems for possible use in nanoelectronics. The template-based synthesis method used here is generic, and it has the potential to provide control over the structure and characteristics of the resulting MOM nanowires. By virtue of their heterojunction structure, MOM nanowires have the potential to overcome some of the drawbacks associated with all-oxide nanowire building blocks, and they present a rare opportunity to measure directly fundamental functional properties of nanoscale oxides.

A Single Universal Construction Rule for the Structural Synthesis of Mechanisms

2016 ◽  
Author(s):  
Elad Hahn ◽  
Offer Shai
Keyword(s):  
Synthesis Method ◽  
Building Blocks ◽  
Construction Rule ◽  
Synthesis Methods ◽  
Rigidity Theory ◽  
Structural Synthesis ◽  
Graph Representations ◽  
Synthesis Of Mechanisms ◽  
Different Types ◽  
Universal Construction

In the field of structural synthesis of mechanisms several synthesis methods have been developed using different approaches. One of the more interesting approaches was that of bottom-up construction via the combination of modular structural groups, known as Assur groups. This approach is combined with new graph representations of mechanisms taken from rigidity theory, capable of representing all the different types of planar and spatial mechanisms. With the strong mathematical base of rigidity theory, a new synthesis method is proposed based on Assur groups, which are reformulated in terms of graph theory and renamed Assur Graphs. Using a single universal construction rule, Assur Graphs of different types and of any number of links are constructed, creating a complete set of building blocks for the synthesis of feasible mechanisms. As its name implies, the single universal construction is applicable for mechanisms of all types of joints and links, for planar or spatial motion.

Preparation of SiC/SiO2 Core-Shell Coaxial Nanostructure

2010 ◽  
Vol 123-125 ◽  
pp. 755-758 ◽  
Author(s):  
Yu Lian Wang ◽  
Guang Zhu ◽  
Xiao Ping Zou ◽  
Jin Cheng
Keyword(s):  
Direct Synthesis ◽  
Synthesis Method ◽  
Silicon Monoxide ◽  
Building Blocks ◽  
Core Shell ◽  
Amorphous Sio2 ◽  
Coaxial Nanocables ◽  
Coaxial Nanostructure ◽  
Novel Structures ◽  
Structural Characterizations

A simple direct synthesis method was used to synthesis SiC/SiO2 core–shell coaxial nanocables by thermal evaporation of the mixture powders of silicon monoxide and active carbon at 1300°C and condensation on Si substrate without assistance of any catalyst. The SiC core typically has diameters of 10-40 nm and is covered by a uniform layer of 2-10nm thick amorphous SiO2. A double vapor–solid growth process is proposed for the formation of this novel structures based on detailed structural characterizations. The cable nanostructures may find applications as building blocks in nanomechanical or nanoelectronic devices.

scholarly journals Multibody-Based Topology Synthesis Method for Large Stroke Flexure Hinges

2016 ◽  
Author(s):  
M. Naves ◽  
D. M. Brouwer ◽  
R. G. K. M. Aarts
Keyword(s):  
Shape Optimization ◽  
Synthesis Method ◽  
Solution Space ◽  
Building Blocks ◽  
Optimization Method ◽  
Mode Shapes ◽  
Optimal Layout ◽  
Flexure Hinges ◽  
Derivative Free ◽  
Block Approach

Large stroke flexure mechanisms inherently lose stiffness in supporting directions when deflected due to load components in compliant bending and torsion directions. To maximize performance over the entire range of motion, a topology optimization suited for large stroke mechanisms is required. In this paper a new multibody-based topology synthesis method is presented for optimizing large stroke flexure hinges. This topology synthesis consists of a layout variation strategy based on a building block approach combined with a shape optimization to obtain the optimal design tuned for a specific application. A derivative free shape optimization method is used to optimize high complexity flexure mechanisms in a broad solution space. To obtain the optimal layout, three predefined “building blocks” are proposed which are consecutively combined to find the best layout with respect to a specific design criteria. More specifically, this new method is used to optimize a flexure hinge aimed at maximizing the first disturbing eigenfrequency. The optimized topology shows an increase in frequency of a factor ten with respect to the customary three flexure cross hinge, which represents a huge improvement in performance. The numerically predicted natural frequencies and mode shapes have been verified experimentally.

Designing ordered nanoarrays from aqueous solutions

2006 ◽  
Vol 78 (9) ◽  
pp. 1741-1747 ◽  
Author(s):  
Lionel Vayssieres
Keyword(s):  
Aqueous Solutions ◽  
Large Scale ◽  
Metal Salt ◽  
Essential Feature ◽  
Low Cost ◽  
Synthesis Method ◽  
Functional Materials ◽  
Building Blocks ◽  
Hole Transport ◽  
The Creation

The design and large-scale fabrication of ordered arrays consisting of advanced and well-defined building blocks such as quantum dots, nanorods, and nanowires is essential to the creation of new devices based on nanoscience. A concept as well as a growth model and a thin film technique have been developed by the author to contribute to these challenges. These ideas and synthesis method led to the creation of a new generation of functional materials from aqueous solutions with designed morphology and orientation, which are in better adequacy with their applications. Nanomaterials are growing directly onto various substrates by heteronucleation from the thermohydrolysis of aqueous metal salt precursors. Although this bottom-up technique allows the generation of anisotropic and oriented building blocks of various length scales and on many types of substrates, it is carried out without template, surfactant, applied field, or undercoating. Therefore, high-purity, low-cost, and large-scale fabrication of advanced nanomaterials is achieved. In addition, the direct contact growth between 1-D building blocks and their substrate is an essential feature to take full advantage of oriented nanorods, that is, a direct path for electron/hole transport. This specific conformation is of particular interest in developing more efficient devices such as sensors and photovoltaic cells.

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