Hydrothermal topological synthesis and photocatalyst performance of orthorhombic Nb2O5 rectangle nanosheet crystals with dominantly exposed (010) facet

Hydraulic rescue spreaders are used by emergency response personnel to extricate occupants from a vehicle crash. A lighter and more portable rescue spreader is required for better usability and to enable utilization in a variety of scenarios. To meet this requirement, topological synthesis, dimensional synthesis, and an optimization were used to develop a solution linkage. The topological synthesis technique demonstrates that ten links are the minimum possible number that achieves the desired motion without depending primarily on rotation of the spreader jaws. A novel integrated kinematic-structural dimensional synthesis technique is presented and used in a grid-search optimizing the linkage dimensions to minimize linkage mass. The resulting ten-bar linkage meets or exceeds the kinematic performance parameters while simultaneously achieving a near-optimum predicted mass.

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Topological Synthesis of All 2D Mechanisms Through Assur Graphs

Volume 2: 34th Annual Mechanisms and Robotics Conference, Parts A and B ◽

10.1115/detc2010-28926 ◽

2010 ◽

Cited By ~ 5

Author(s):

Offer Shai

Keyword(s):

Rigidity Theory ◽

Topological Structures ◽

Mapping Algorithm ◽

Systematic Construction ◽

Graph Classes ◽

Assur Group ◽

Group Concept ◽

Infinite Set ◽

Topological Synthesis

It is well known that every planar kinematical linkage can be decomposed into basic topological structures referred as Assur Groups. A new reformulation of Assur Group concept into the terminology of rigidity theory, as Assur Graphs, has yielded the development of new theorems and methods. The paper reports on an algorithm for systematic construction of Assur Graph classes, termed fundamental Assur Graphs. From each fundamental Assur Graph it is possible to derive an infinite set of different Assur Graphs. This mapping algorithm is proved to be complete and sound, i.e., all the Assur Graphs appear in the map and each graph in the map is an Assur Graph. Once we possess the mapping of all the Assur Graphs, all valid kinematical linkage topologies can be constructed through various Assur Graph compositions.

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Topological Synthesis for Linkage Mechanism Design Using the Minimum Potential Energy Principle

Volume 2: 31st Design Automation Conference, Parts A and B ◽

10.1115/detc2005-85587 ◽

2005 ◽

Author(s):

Hae Chang Gea ◽

Jaehyun Kwon

Keyword(s):

Potential Energy ◽

Mechanism Design ◽

Compliant Mechanism ◽

Analysis Method ◽

Dimensional Synthesis ◽

Linkage Mechanism ◽

Minimum Potential Energy ◽

Minimum Potential ◽

Number Synthesis ◽

Topological Synthesis

A mechanism is a device transmits motion in a predetermined manner in order to accomplish specific objectives. Mechanism design can be divided into three steps: type synthesis, number synthesis and dimensional synthesis, where the number synthesis is also called topological synthesis. In this paper, a new approach for topological synthesis and dimensional synthesis of linkage mechanism design with pin joints is presented. This approach is based on the discrete element approach which always provides clear definitions of number of linkages and joints. In order to extend its applications beyond the compliant mechanism, a novel analysis method based on the principle of minimum potential energy for linkage topology optimization is employed. Unlike the traditional FEM based approaches, this novel analysis method can be applied to multiple joint linkage designs directly. Genetic Algorithm is chosen as the optimizer. Finally, a few design examples from the proposed method are presented.

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Topological Synthesis and Analysis of Geared Linkages Based on Matrix Powers

15th Design Automation Conference: Volume 3 — Mechanical Systems Analysis, Design and Simulation ◽

10.1115/detc1989-0148 ◽

1989 ◽

Author(s):

D. G. Olson ◽

A. G. Erdman ◽

D. R. Riley

Keyword(s):

Adjacency Matrix ◽

Digital Computer ◽

Visual Inspection ◽

Kinematic Chain ◽

New Method ◽

Graph Representation ◽

Kinematic Chains ◽

Degree Matrix ◽

Topological Synthesis

Abstract A new method for transforming pin-jointed kinematic chains into geared linkages is introduced. The method utilizes the graph representation in the form of the adjacency matrix and the “degree matrix” [20], and the powers of these matrices. The method involves first determining the feasible locations for assigning gear pairs in a kinematic chain, followed by determining which of the choices are distinct, and finally, determining the distinct possible ways of assigning the ground link for each distinct “geared kinematic chain” so formed. Because the method is based on matrix manipulations and does not rely on visual inspection, it is easily implemented on a digital computer. The method is applied to an example class of geared mechanism, the single-dof geared seven-bar linkages.

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