Design and Mobility Analysis of Large Deployable Mechanisms Based on Plane-Symmetric Bricard Linkage

2016 ◽  
Vol 139 (2) ◽  
Author(s):  
Xiaozhi Qi ◽  
Hailin Huang ◽  
Zhihuai Miao ◽  
Bing Li ◽  
Zongquan Deng

In this paper, a class of large deployable mechanisms constructed by plane-symmetric Bricard linkages is presented. The plane-symmetric Bricard linkage is a closed-loop overconstrained spatial mechanism composed of six hinge-jointed bars, which has one plane of symmetry during its deployment process. The kinematic analysis of the linkage is presented from the perspectives of geometric conditions, closure equations, and degree-of-freedom. The results illustrate that the linkage has one degree-of-freedom and can be deployed from the folded configuration to one rectangle plane. Therefore, the plane-symmetric Bricard linkage can be used as a basic deployable unit to construct larger deployable mechanisms. Four plane-symmetric Bricard linkages can be assembled into a quadrangular module by sharing the vertical bars of the adjacent units. The module is a multiloop deployable mechanism and has one degree-of-freedom. The singularity analysis of the module is developed, and two methods to avoid singularity are presented. A large deployable mast, deployable plane truss, and deployable ring are built with several plane-symmetric Bricard linkages. The deployment properties of the large deployable mechanisms are analyzed, and computer-aided design models for typical examples are built to illustrate their feasibility and validate the analysis and design methods.

Author(s):  
Xiaozhi Qi ◽  
Bing Li ◽  
Zhihuai Miao ◽  
Hailin Huang

In this paper, a class of large deployable mechanisms constructed by plane-symmetric Bricard linkage is presented. The plane-symmetric Bricard linkage is a closed-loop over-constrained spatial mechanism composed of six hinge-jointed bars, which has one plane of symmetry during its deployment process. The kinematic analysis of the linkage is presented from the perspectives of geometric conditions, closure equations and degree of freedom. The results illustrates that the linkage has one degree of freedom, and it can be deployed from the folded configuration to one rectangle plane. Therefore, the plane-symmetric Bricard linkage can be used to construct lager deployable mechanism as basic deployable unit. Four plane-symmetric Bricard linkages can be assembled to a quadrangular module by sharing the vertical bars of adjacent units. The module is a multi-loop deployable mechanism and has one degree of freedom by the mobility analysis. Large deployable mast, deployable plane truss and deployable ring are built by a plurality of plane-symmetric Bricard linkages. The computer-aided design models for typical examples are built to illustrate their feasibility and validate the analysis and design methods.


2017 ◽  
Vol 10 (1) ◽  
Author(s):  
Chenhan Guang ◽  
Yang Yang

The radial folding ratio of single-vertex multicrease rigid origami, from the folded configuration to the unfolded configuration, is satisfactory. In this study, we apply two approaches to add nonzero thickness for this kind of origami and identify different geometrical characteristics. Then, the model of the secondary folding origami, which can help to further decrease the folding ratio, is constructed. We apply the method of constraining the edges of the panels on prescribed planes to geometrically obtain the kinematic model. Based on the kinematic model and the screw theory, the nonzero thickness origami is transformed into the deployable mechanism with one degree-of-freedom (1DOF). Other similar mechanisms can be derived based on this basic configuration. The computer-aided design examples are presented to indicate the feasibility.


Energies ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1943
Author(s):  
Bader N. Alajmi ◽  
Mostafa I. Marei ◽  
Ibrahim Abdelsalam ◽  
Mohamed F. AlHajri

A high-frequency multi-port (HFMP) direct current (DC) to DC converter is presented. The proposed HFMP is utilized to interface a photovoltaic (PV) system. The presented HFMP is compact and can perform maximum power point tracking. It consists of a high-frequency transformer with many identical input windings and one output winding. Each input winding is connected to a PV module through an H-bridge inverter, and the maximum PV power is tracked using the perturb and observe (P&O) technique. The output winding is connected to a DC bus through a rectifier. The detailed analysis and operation of the proposed HFMP DC-DC converter are presented. Extensive numerical simulations are conducted, using power system computer aided design (PSCAD)/electromagnetic transients including DC (EMTDC) software, to evaluate the operation and dynamic behavior of the proposed PV interfacing scheme. In addition, an experimental setup is built to verify the performance of the HFMP DC-DC converter.


2016 ◽  
Vol 8 (3) ◽  
Author(s):  
Hailin Huang ◽  
Bing Li ◽  
Jianyang Zhu ◽  
Xiaozhi Qi

This paper proposes a new family of single degree of freedom (DOF) deployable mechanisms derived from the threefold-symmetric deployable Bricard mechanism. The mobility and geometry of original threefold-symmetric deployable Bricard mechanism is first described, from the mobility characterstic of this mechanism, we show that three alternate revolute joints can be replaced by a class of single DOF deployable mechanisms without changing the single mobility characteristic of the resultant mechanisms, therefore leading to a new family of Bricard-derived deployable mechanisms. The computer-aided design (CAD) models are used to demonstrate these derived novel mechanisms. All these mechanisms can be used as the basic modules for constructing large volume deployable mechanisms.


1994 ◽  
Vol 16 (2) ◽  
pp. 89-95
Author(s):  
Muhammad Taher Abuelma'atti

A simple model for nonuniform distributed RC structures is presented. The model consists of three passive elements only and can be used for modelling nonuniform distributed RC structures involving exponential, hyperbolic sine squared, hyperbolic cosine squared and square taper geometries. The model can be easily implemented for computer-aided analysis and design of circuits and systems comprising nonuniform distributed RC structures.


Author(s):  
Raffaele Di Gregorio

In spherical-mechanism kinematics, instantaneous pole axes play the same role as, in planar-mechanism kinematics, instant centres. Their locations only depend on the mechanism configuration when spherical single-degree-of-freedom mechanisms are considered. Such a property makes them a tool to visualize and/or to analyse the instantaneous kinematics of those mechanisms. This article addresses the singularity analysis of single-degree-of-freedom spherical mechanisms by exploiting the properties of instantaneous pole axes. An exhaustive enumeration of the geometric conditions which occur for all the singularity types is given, and a general analytical method based on this enumeration is proposed for implementing the singularity analysis. The proposed analytical method can be used to generate systems of equations useful either for finding the singularities of a given mechanism or to synthesize mechanisms that have to match specific requirements about the singularities.


1973 ◽  
Vol 95 (3) ◽  
pp. 685-694 ◽  
Author(s):  
F. Y. Chen

The cam-and-follower mechanism is represented by a lumped parameter model of finite degrees of freedom, in which nonlinear system parameters may be taken into account. An approximate dynamic analysis of the system excited by either functional or numerical form of the base motion of a cam is obtained. The method of solution which uses an interpolating polynomial for approximating the excitation function and mechanical quadrature for evaluating the convolution integral is well suited for computer programming. A digital computer program for analysis based on this scheme is developed. In order to utilize the analysis tool for design purposes, parametric studies are conducted, design stratagems are presented and a rational procedure of closed loop computer-aided design is outlined and discussed.


Sign in / Sign up

Export Citation Format

Share Document