A Novel 1-DOF Deployable Mechanism for Parabolic Cylindrical Surface Approximation

2019 ◽  
Author(s):  
Hang Xiao ◽  
Shengnan Lu ◽  
Xilun Ding
Keyword(s):  
Cylindrical Surface ◽  
Static Load ◽  
Geometric Parameters ◽  
Surface Approximation ◽  
Magnification Ratio ◽  
Load Analysis ◽  
Deployable Mechanism

Abstract This paper presents a novel deployable mechanism for approximating the parabolic cylindrical surface. The proposed mechanism, which can deploy and fold synchronously in the radial and axial directions, is constructed by double four-bar linkages and scissor linkages. In the fully deployed configuration, the mechanism can approximate a cylindrical surface. It can also be folded compactly into a bundle. The radial and axial deployable mechanisms are described and their position kinematics are solved. A synchronous mechanism is designed to ensure the synchronous movement of the radial and axial mechanisms. Geometric parameters of the mechanism for approximating a given parabolic cylindrical surface are obtained. The magnification ratio of the designed mechanism is calculated. The best choice of actuator is determined through static-load analysis.

Geometric Design of a Bio-Inspired Flapping Wing Mechanism Based on Bennett-Derived 6R Deployable Mechanisms

2014 ◽  
Author(s):  
Huang Hailin ◽  
Li Bing
Keyword(s):  
Flapping Wing ◽  
Geometric Design ◽  
Geometric Parameters ◽  
Degree Of Freedom ◽  
Single Degree Of Freedom ◽  
Flapping Motion ◽  
Single Degree ◽  
Revolute Joints ◽  
Air Vehicle ◽  
Deployable Mechanism

In this paper, we present the concept of designing flapping wing air vehicle by using the deployable mechanisms. A novel deployable 6R mechanism, with the deploying/folding motion of which similar to the flapping motion of the vehicle, is first designed by adding two revolute joints in the adjacent two links of the deployable Bennett linkage. The mobility of this mechanism is analyzed based on a coplanar 2-twist screw system. An intuitive projective approach for the geometric design of the 6R deployable mechanism is proposed by projecting the joint axes on the deployed plane. Then the geometric parameters of the deployable mechanism can be determined. By using another 4R deployable Bennett connector, the two 6R deployable wing mechanisms can be connected together such that the whole flapping wing mechanism has a single degree of freedom (DOF).

Batter Pile Static Load Test and Analysis

2012 ◽  
Vol 256-259 ◽  
pp. 1139-1143
Author(s):  
Li Lan Zhang ◽  
Yao Dong Wu
Keyword(s):  
Stress State ◽  
Static Load ◽  
Resistance Coefficient ◽  
Load Test ◽  
Soil Resistance ◽  
Test Results ◽  
Static Load Test ◽  
Foundation Soil ◽  
Load Analysis ◽  
Actual Stress

This paper through the test results and theoretical calculation of the batter pile static load, analysis of the actual stress state of cables, and according to the test results to determine the level of the foundation soil resistance coefficient ratio and allow level a transplant.

Design and Analysis of a Cable-Driven Deployable Cylindrical Mechanism

2018 ◽  
Author(s):  
Hang Xiao ◽  
Shengnan Lu ◽  
Xilun Ding
Keyword(s):  
Optimal Design ◽  
Cylindrical Surface ◽  
Geometric Shape ◽  
Design Parameters ◽  
Cable System ◽  
Experimental Prototype ◽  
Deployable Mechanism

This paper presents the design of a deployable cylindrical mechanism which is driven by cable. The deployable mechanism can be deployed to approximate a cylindrical surface and be folded into a compact bundle. Construction of the cylindrical surfaces with Bennett linkages is introduced. Geometric shape of the connecting bars and structure of the joints are designed for compact bundle-folding configuration and avoiding the interference. Position kinematics of the mechanism is solved. Cable system is designed to drive the mechanism to deploy. A direction-changeable mechanism used for cable pulleys is proposed and the optimal design parameters are obtained. A ground experimental prototype is fabricated to validate the proposed design and to show the feasibility of the designed mechanism.

Approximation of Cylindrical Surfaces With Deployable Bennett Networks

2016 ◽  
Author(s):  
Shengnan Lu ◽  
Dimiter Zlatanov ◽  
Xilun Ding
Keyword(s):  
Modeling And Simulation ◽  
Case Studies ◽  
Cylindrical Surface ◽  
Kinematic Analysis ◽  
Geometric Parameters ◽  
Degree Of Freedom ◽  
Curved Surfaces ◽  
Deployable Structures ◽  
Elliptical Cylinders ◽  
Insight Into

This paper presents a one-degree-of-freedom network of Bennett linkages which can be deployed to approximate a cylindrical surface. The geometry of the unit mechanism is parameterized and its position kinematics is solved. The influence of the geometric parameters on the deployed shape is examined. Further kinematic analysis isolates those Bennett geometries for which a cylindrical network can be constructed. The procedure for connecting the unit mechanisms in a deployable cylinder is described in detail and used to gain insight into, and formulate some general guidelines for, the design of linkage networks which unfold as curved surfaces. Case studies of deployable structures in the shape of circular and elliptical cylinders are presented. Modeling and simulation validate the proposed approach.

A Novel Deployable Mechanism With Two Decoupled Degrees of Freedom

2013 ◽  
Author(s):  
Shengnan Lu ◽  
Dimiter Zlatanov ◽  
Xilun Ding ◽  
Rezia Molfino ◽  
Matteo Zoppi
Keyword(s):  
Degrees Of Freedom ◽  
Degree Of Freedom ◽  
Deployable Structures ◽  
Two Component ◽  
Potential Applications ◽  
Magnification Ratio ◽  
Deployable Mechanism ◽  
The Relationship ◽  
Kinematic Properties ◽  
Kinematic Simulations

This paper presents a novel deployable mechanism. Unlike most deployable structures, which have one degree of freedom, the proposed device can be deployed and compacted independently in two directions. This widens the range of its potential applications, including flexible industrial fixtures and deployable tents. The mechanism’s basic deployable unit is assembled by combining a scissor linkage and a Sarrus linkage. The kinematic properties of the two component linkages and the combined unit are analyzed. The new deployable mechanism is obtained by linking the deployable units. The Mobility and kinematics are analyzed. The relationship between the degree of overconstraint and the number of deployable units is derived. The magnification ratio is calculated as a function of the geometry of the link and the number of deployable units. Finally, kinematic simulations are performed to validate the proposed design and analysis.

scholarly journals Wind Load Analysis on A Multistoreyed Building Curved in Plan

2021 ◽  
Vol 10 (2) ◽  
pp. 144-147
Author(s):  
K Bala Venkata Sai ◽  
M Pavan Kumar ◽  
N Madhu Veena ◽  
D Muthu ◽  
G. Nandhini
Keyword(s):  
Static Load ◽  
Wind Load ◽  
Beam Line ◽  
Bending Moments ◽  
Shear Forces ◽  
First Case ◽  
Radial Beam ◽  
Load Component ◽  
Load Analysis ◽  
Support Reactions

: In this study a tall G+8 storied curved in plan (comprising an external and internal curved facade) has been analysed for wind acting in specified directions using STAAD pro v8i.For the curved profile, the wind load component has been calculated for each radial beam line. The combination of static load and wind load are taken into consideration. In the first case, the wind has been assumed to act towards the centre of the arc of the circle and in the second, away from the centre. The post processing reverberation in terms of bending moments, shear forces and support reactions has been studied in relation to the wind directions. Due to the effect of wind load on the structure, the storey-sage variation of the result with respect to different parameters are to be compared. The stiffness of the structure as a whole is expected to vary with the changed direction of the wind. The result would result in a parametric study of the effect of wind direction on curved profile. The orientation of the curved structure with respect to the direction of wind load has been studied.

Modelling and analysis for a cylindrical net-shell deployable mechanism

2019 ◽  
Vol 22 (15) ◽  
pp. 3149-3160
Author(s):  
Fei Lin ◽  
Chuanzhi Chen ◽  
Jinbao Chen ◽  
Meng Chen
Keyword(s):  
Cylindrical Surface ◽  
Screw Theory ◽  
Equivalent Model ◽  
Analysis Method ◽  
Deployable Structures ◽  
Single Degree Of Freedom ◽  
Space Industry ◽  
Smooth Motion ◽  
Motion Performance ◽  
Deployable Mechanism

Existing cylindrical deployable structures have poor controllability of deployment or weak bearing capacity. In order to satisfy the application needs of cylindrical deployable structures in the space industry, a cylindrical net-shell deployable mechanism is established in this article. The proposed cylindrical net-shell deployable mechanism has a regular cuboid shape in the folded state and a truss structure in the deployed state, and it can fit cylindrical surface, parabolic cylindrical surface, sine cylindrical surface and so on. Furthermore, based on reciprocal screw theory and screw synthesis theory, the mobility of cylindrical net-shell deployable mechanism in the whole motion cycle is analysed by the proposed equivalent model method. Results show that the cylindrical net-shell deployable mechanism is a single-degree-of-freedom mechanism. Moreover, a prototype is manufactured, and its motion performance is tested. The experiment shows that the cylindrical net-shell deployable mechanism has a smooth motion performance, and the mobility analysis method for complex coupled mechanism in this study is valid. This study has a certain significance in expanding the application field of cylindrical shell structure.

scholarly journals Numerical analysis of spinal stabiliser in spondylolisthesis treatment with pedicle screws

2019 ◽  
Vol 252 ◽  
pp. 08006
Author(s):  
Jarosław Zubrzycki
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Numerical Analysis ◽  
3D Model ◽  
Static Load ◽  
Pedicle Screws ◽  
The Body ◽  
The Other ◽  
The Finite Element Method ◽  
Load Analysis

The aim of the research on experimental parts was to analyse the influence of the lumbar stabilisation on the strength aspects of the lumbar part of human spine and stabiliser in case of spondylolisthesis treatment. The models were built with the use of pre-surgical CT diagnostics, routinely used in medical practice. MIMICS software was used to process the results of the neuroimaging research and to create a 3D model. Two models were built: one with and the other without a stabilizer. Afterwards, a static load analysis for the load coming from the upper part of the body was done. Analysis was performed using the finite element method (FEA). The performed simulations enabled to determine the stress in particular discs for both models, with and without transpedicular stabiliser.

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