Incorporating Fixed-Point and -Line Constraints and Tolerance Based Synthesis in 4MDS

2015 ◽  
Author(s):  
Anurag Purwar ◽  
Saurabh Bhapkar ◽  
Q. J. Ge
Keyword(s):  
Theoretical Foundation ◽  
Geometric Constraints ◽  
Machine Design ◽  
Design Stage ◽  
Design System ◽  
Motion Synthesis ◽  
Kinematic Mapping ◽  
Line Tangent ◽  
Fixed Line ◽  
Best Fit

This paper presents implementation of fixed-pivots, ground-link line, and tolerance based motion synthesis in the 4MDS (Four-Bar Motion Design System). This is a continuation of the first work reported on 4MDS, which provides an interactive, graphical, and geometric constraint based mechanism design system for the exact- and approximate-motion synthesis problems. Theoretical foundation of the 4MDS is laid over a kinematic mapping based unified formulation of the geometric constraints (circle, fixed-line, line-tangent-to-a-circle) associated with the mechanical dyads (RR, PR, and RP) of a planar four-bar mechanism. An efficient algorithm extracts the geometric constraints of a given motion task and determines the best dyad types as well as their dimensions that best fit to the motion. Often, Mechanism designers need to impose additional geometric constraints, such as specification of location of fixed pivots or ground-link line. If synthesized mechanism suffers from branch, circuit, or order defect, they may also desire rectified solutions by allowing a tolerance to certain or all task positions. Such functions are crucial to a practitioner and much needed during the conceptual design stage of machine design process.

A Task Driven Approach to the Synthesis of Spherical 4R Linkages Using Algebraic Fitting Method

2013 ◽  
Author(s):  
Ping Zhao ◽  
Xiangyun Li ◽  
Anurag Purwar ◽  
Kartik Thakkar ◽  
Q. J. Ge
Keyword(s):  
Linear Method ◽  
Geometric Constraints ◽  
Motion Generation ◽  
Constraint Manifold ◽  
Fitting Method ◽  
Kinematic Mapping ◽  
Motion Approximation ◽  
The Given ◽  
Best Fit ◽  
Additional Constraints

This paper studies the problem of spherical 4R motion approximation from the viewpoint of extraction of circular geometric constraints from a given set of spherical displacements. This paper extends our planar 4R linkage synthesis work to the spherical case. By utilizing kinematic mapping and quaternions, we map spherical displacements into points and the workspace constraints of the coupler into intersection of algebraic quadrics (called constraint manifold), respectively, in the image space of displacements. The problem of synthesizing a spherical 4R linkage is reduced to finding a pencil of quadrics that best fit the given image points in the least squares sense. Additional constraints on the pencil identify the quadrics that represent a spherical circular constraint. The geometric parameters of the quadrics encode information about the linkage parameters which are readily computed to obtain a spherical 4R linkage that best navigates through the given displacements. The result is an efficient and largely linear method for spherical four-bar motion generation problem.

The Role of Constraints and Human Interaction in Evolving MEMS Designs: Microresonator Case Study

2004 ◽  
Author(s):  
Raffi Kamalian ◽  
Alice M. Agogino ◽  
Hideyuki Takagi
Keyword(s):  
Genetic Algorithms ◽  
Geometric Constraints ◽  
Human Interaction ◽  
Design System ◽  
Current State ◽  
Mems Resonator ◽  
Computer Aided ◽  
Generative Methods

In this paper we review the current state of automated MEMS synthesis with a focus on generative methods. We use the design of a MEMS resonator as a case study and explore the role that geometric constraints and human interaction play in a computer-aided MEMS design system based on genetic algorithms.

A hierarchical machine design system Himades-1

1984 ◽  
Vol 16 (2) ◽  
pp. 105
Author(s):  
K. Kitajima ◽  
H. Yoshikawa
Keyword(s):  
Machine Design ◽  
Design System

Highways Design Taking into Account Climatic Features in the Route Area

2021 ◽  
pp. 125-136
Author(s):  
Т. В. Самодурова ◽  
Н. Ю. Алимова ◽  
О. А. Волокитина ◽  
О. В. Гладышева
Keyword(s):  
Bearing Capacity ◽  
Computer Aided Design ◽  
Systematic Approach ◽  
Weather Conditions ◽  
Design Stage ◽  
Design System ◽  
Computer Aided ◽  
Calculation Methodology ◽  
Aided Design ◽  
Climatic Features

Постановка задачи. Для получения оптимальных проектных решений, удовлетворяющих условиям безопасности движения в сложных погодных условиях, необходимо сравнение вариантов автомобильных дорог по условиям снегонезаносимости. Такие расчеты должны стать составной частью системы автоматизированного проектирования САПР-АД. Результаты. Предложен системный поход к решению задачи, определен перечень информации, необходимой для проведения расчетов. Выполнен анализ результатов исследований по снегозаносимости дорог, проводимых в России и за рубежом. Предложены расчетные схемы и модели для оценки вариантов продольного профиля и земляного полотна автомобильной дороги по снегозаносимости. Предложены решения для оценки вариантов плана трассы с использованием карт с расчетными параметрами метелей. Выводы. Реализация предложенной методики проведения расчетов позволит на стадии проектирования оценить варианты автомобильной дороги по условиям снегозаносимости. Statement of the problem. In order to obtain optimal design solutions that meet the conditions of safety traffic in difficult weather conditions, it is necessary to compare the options of highways according to the snow tolerance conditions. Such calculations should become an integral part of the CAD-AD computer-aided design system. Results. A systematic approach to solving the problem is set forth, a list of information necessary for calculations is identified. The results analysis of studies on the snow-bearing capacity of roads conducted in Russia and abroad is carried out. Calculation schemes and models are suggested to evaluate options for the longitudinal profile and the roadbed for the snow-bearing capacity. Solutions for evaluating variants of the route plan using maps with calculated parameters of snowstorms are proposed. Conclusions. The implementation of the proposed calculation methodology will make it possible at the design stage to evaluate the options of the highway according to the conditions of the snow-bearing capacity.

COVIRDS: Shape Modeling in a Virtual Reality Environment

1997 ◽  
Author(s):  
Tushar H. Dani ◽  
Chi-Cheng P. Chu ◽  
Rajit Gadh
Keyword(s):  
Computer Aided Design ◽  
Visual Display ◽  
Design Stage ◽  
Design System ◽  
Concept Design ◽  
Virtual Design ◽  
Cad Systems ◽  
Product Concept ◽  
Shape Models ◽  
Solid Models

Abstract Rapid shape creation and visualization of solid models remains a tedious task despite advances in the field of Computer Aided Design (CAD)/Solid Modeling. CAD systems require a significant level of detail, such as vertices, edges, and faces to be specified by the user, even before the simplest of shapes can be created and viewed. In addition, most CAD systems have an essentially 2D interface for designing artifacts. This makes artifact visualization, for example by interactive rotation, difficult since all manipulations have be achieved by 2D translation of the mouse or by typing in the required angles of rotation. The limited visualization capability and the requirement to create shapes through the specification of low level entities is especially cumbersome in the concept shape design stage. This paper describes the Conceptual Virtual Design System, COVIRDS, a tool for product concept design. COVIRDS provides an intuitive voice and hand input-based interface for modeling of products using a ‘construction’ approach. Product shape models are created by ‘attaching’ simpler parametrically defined ‘Shape Elements’ to other elements to create more complex models. Voice commands are used to instantiate shape elements and change their parameters, for example, the width, length and height of a block element. 3D hand input is used for positioning shape elements during element attachment. The voice and hand input-based interface together with a stereoscopic visual display facilitates rapid creation and visualization of concept shape models.

A Development of Wire Path Searching Module Using Extended RCA Method

1996 ◽  
Author(s):  
Seong-Hyuk Yim ◽  
Soo-Hong Lee
Keyword(s):  
Physical Properties ◽  
Shortest Path ◽  
Free Space ◽  
Design Stage ◽  
Design System ◽  
System Configuration ◽  
Dependency Structure ◽  
Leading Role ◽  
Special Cases ◽  
Mutual Relations

Abstract This study deals with a development of wire path searching module as a part of automotive wire harness design system. Wire path searching module manages the free space, finds transition locations, and creates bundle paths to dramatically reduce a tedious iterative routing process which results in easy optimization of the bundle paths. A prime policy in the system configuration is to compromise between man’s and computer’s ability, and make it possible a designer’s leading role in designing process. Human input is indispensable to cope with the special cases which were not considered in the initial design stage of the system. In this study, we improve the previous shortest-path-finding algorithm (VGraph and RCA method) into a new method called Extended RCA. Bundles, connectors and transitions are handled as objects so one can manage and modify physical properties of the objects easily. Therefore a verification is allowed at any desired stage of design. The reuse of previous result is facilitated by using Dependency Structure, which represents the mutual relations among connectors, transitions, and bundles. Dependency Structure makes it possible the elimination of redundant calculating process, and consequently shorter routing time.

Cross Method and Design Process for DSF Elements

2017 ◽  
Vol 42 (4) ◽  
pp. 36-43 ◽  
Author(s):  
Sertaç Ilter ◽  
S.Müjdem Vural
Keyword(s):  
Architectural Design ◽  
Natural Ventilation ◽  
Evaluation Method ◽  
Building Envelope ◽  
Design Stage ◽  
Design System ◽  
Human Comfort ◽  
Early Design Stage ◽  
Preliminary Design Stage ◽  
Contemporary Architecture

The double-skin façade (DSF) is one of the most crucial paradigms of building envelope design in last decades. DSF prospects a unified architectural phenomenon based on comfort rank of building driven by the dogmas of aesthetic-glass façade and practical-natural ventilation aspirations. Therefore, the utilization of DSF has been the most prevalent catalyst for architectural design. The study discusses to structure a valid evaluation method focusing on DSF elements in order to fragment human comfort standards within asserting an accurate system in the preliminary design stage. The study significantly examines the tools/ways of integrating DSFs' human comfort parameters in contemporary architecture though a convincing design system. Apparently, the study aims to provide a proposed guideline within a established analyzing system for architects in order to better formation of DSF elements; which refers and promote the human comfort standards. The results demonstrate a modest insight on understanding the potentials of DSF elements in the early design stage significantly following defined architectural conceptions; cooling, lighting, thermal, acoustic and visual comfort intensity. Based on obtained data; study aims to enclose a diminutive knowledge or demonstration of how the concept might work for future development of contemporary architecture within DSF area.

scholarly journals AI and the Future of the Machine Design

2017 ◽  
Vol 139 (10) ◽  
pp. 38-43 ◽  
Author(s):  
Ahmed K. Noor
Keyword(s):  
Mixed Reality ◽  
Technical Aspect ◽  
Machine Design ◽  
Design System ◽  
Self Healing ◽  
Cognitive Computing ◽  
Slide Rule ◽  
Human Engineer ◽  
Advanced Robotics

This article discusses advantages of artificially intelligent (AI) systems and future of machine design. Advances in AI, combined synergistically with other technologies such as cognitive computing, Internet of Things, 3D (or even 4D) printing, advanced robotics, virtual and mixed reality, and human–machine interfaces are transforming what, where, and how products are designed, manufactured, assembled, distributed, serviced, and upgraded. The research and related activities may ultimately result in the development of self-repairing, self-healing, self-adaptive, self-reconfiguring systems—and products that ‘operationally improve’ themselves. Instead of depreciating in value and capability, such products could improve over time. In time, the role of the human engineer may be that of a director rather than of a producer. Much of the technical aspect of engineering will be moved to the machine-based design system, just as one need not be able to operate a slide rule or complete an isometric drawing to be a successful engineer today.

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