Characteristic Surfaces for Three-Position Function Generation With Planar Four-Bar Mechanisms

1989 ◽  
Vol 111 (1) ◽  
pp. 104-109 ◽  
Author(s):  
C. R. Barker ◽  
P.-L. Tso
Keyword(s):  
Design Problem ◽  
Solution Space ◽  
Function Generation ◽  
Numerical Example ◽  
All Solutions ◽  
The Relationship ◽  
Generation Problem

This paper considers the relationship between the three-position function-generation problem and the solution space for planar four-bar mechanisms. The two infinities of solutions possible are mapped in a plane to determine the locations where particular types of mechanisms occur. It is possible to generate a contour in the mapping plane which joins together all solutions which possess a common characteristic in regard to their link lengths. This same contour can be displayed in the solution space to ascertain the overall characteristics of potential solutions to the design problem. A numerical example is used for illustrative purposes, but the results can be applied to any three-position function-generation problem.

Characteristic Surfaces for Three Position Function Generation With Planar Four Bar Mechanisms

1987 ◽  
Author(s):  
C. R. Barker ◽  
P.-L. Tso
Keyword(s):  
Design Problem ◽  
Solution Space ◽  
Function Generation ◽  
Numerical Example ◽  
All Solutions ◽  
The Relationship ◽  
Generation Problem

Abstract This paper considers the relationship between the three position function generation problem and the solution space for planar four bar mechanisms. The two infinities of solutions possible are mapped in a plane to determine the locations where particular types of mechanisms occur. It is possible to generate a contour in the mapping plane which joins together all solutions which possess a common characteristic in regard to their link lengths. This same contour can be displayed in the solution space to ascertain the overall characteristics of potential solutions to the design problem. A numerical example is used for illustrative purposes, but the results can be applied to any three position function generation problem.

Characteristic Surfaces for Three-Position Motion Generation With Planar Four-Bar Mechanisms

1987 ◽  
Vol 109 (2) ◽  
pp. 183-188
Author(s):  
C. R. Barker ◽  
J. Baumann
Keyword(s):  
Solution Space ◽  
Final Solution ◽  
Motion Generation ◽  
Numerical Example ◽  
All Solutions ◽  
Cartesian Plane ◽  
The Relationship ◽  
Generation Problem

This paper considers the relationship between the three-position motion generation problem and the solution space for planar four-bar mechanisms. After one half of the basic four bar had been selected, two infinities of solutions still remained. These solutions are mapped in a plane to determine where the particular types of mechanisms occur. A contour is then generated in the mapping plane which joins together all solutions which share a common characteristic in regard to their link lengths. This same contour can be displayed in the solution space and in the Cartesian plane in which the motion generation is defined. Significant useful information to assist in selecting the final solution is obtained. A numerical example is used for illustration, but the results can be applied to any three-position motion generation problem.

scholarly journals THE RELATIONSHIP BETWEEN FUNCTIONS AND OUTCOMES OF BIOLOGICALLY-INSPIRED DESIGN

2021 ◽  
Vol 1 ◽  
pp. 3091-3100
Author(s):  
Nicklas Werge Svendsen ◽  
Torben Anker Lenau ◽  
Claus Thorp Hansen
Keyword(s):  
Design Problem ◽  
Historical Data ◽  
Solution Space ◽  
Biologically Inspired ◽  
Problem Types ◽  
Student Teams ◽  
Data Source ◽  
Biologically Inspired Design ◽  
And Function ◽  
The Relationship

AbstractResearch in biologically-inspired design (BID) practice often focus on team composition or ideation based on an already discovered fascinating biological solution principle. However, how are the outcome of the early design phases affecting BID projects' quality?In this study, historical data from 91 reports from student teams documenting their BID efforts from a 3-week course constitute the data source. Thus, the relationship between design problem types, function types, functions descriptions and BID projects' quality is addressed.The study show that especially design problem types and function descriptions affect the BID projects' quality. For instance, BID projects dealing with open-ended problems yield better results than redesign problems with existing solutions operating in a very domain-limited solution space. Next, BID projects obtain the best results when using functions as drivers for analogy searching rather than properties. Finally, BID projects with certain function types seem to have more complicated conceptualization phases.

scholarly journals Mass and spin for classical strings in dS3

2021 ◽  
Vol 2021 (5) ◽  
Author(s):  
Klaas Parmentier
Keyword(s):  
Black Hole ◽  
Evolution Equation ◽  
Cosmic Strings ◽  
Center Of Mass ◽  
Open String ◽  
Conserved Quantities ◽  
Numerical Example ◽  
All Solutions

Abstract We demonstrate that all rigidly rotating strings with center of mass at the origin of the dS3 static patch satisfy the Higuchi bound. This extends the observation of Noumi et al. for the open GKP-like string to all solutions of the Larsen-Sanchez class. We argue that strings violating the bound end up expanding towards the horizon and provide a numerical example. Adding point masses to the open string only increases the mass/spin ratio. For segmented strings, we write the conserved quantities, invariant under Gubser’s algebraic evolution equation, in terms of discrete lightcone coordinates describing kink collisions. Randomly generated strings are found to have a tendency to escape through the horizon that is mostly determined by their energy. For rapidly rotating segmented strings with mass/spin < 1, the kink collisions eventually become causally disconnected. Finally we consider the scenario of cosmic strings captured by a black hole in dS and find that horizon friction can make the strings longer.

A Generalized Performance Sensitivity Synthesis Methodology for Four-Bar Mechanisms

1992 ◽  
Author(s):  
Ming-Yih Lee ◽  
Arthur G. Erdman ◽  
Salaheddine Faik
Keyword(s):  
Solution Space ◽  
Design Solution ◽  
Link Length ◽  
Performance Sensitivity ◽  
Closed Chain ◽  
Synthesis Methodology ◽  
Position Synthesis ◽  
The Relationship ◽  
Accuracy Performance ◽  
Sensitivity Maps

Abstract A generalized accuracy performance synthesis methodology for planar closed chain mechanisms is proposed. The relationship between the sensitivity to variations of link lengths and the location of the moving pivots of four-link mechanisms is investigated for the particular objective of three and four position synthesis. In the three design positions case, sensitivity maps with isosensitivity curves plotted in the design solution space allow the designer to synthesize a planar mechanism with desired sensitivity value or to optimize sensitivity from a set of acceptable design solutions. In the case of four design positions, segments of the Burmester design curves that exhibit specified sensitivity to link length tolerance are identified. A performance sensitivity criterion is used as a convenient and a useful way of discriminating between many possible solutions to a given synthesis problem.

A Comparison of Variety Metrics in Engineering Design

2017 ◽  
Author(s):  
Daniel Henderson ◽  
Kevin Helm ◽  
Kathryn Jablokow ◽  
Seda McKilligan ◽  
Shanna Daly ◽  
...  
Keyword(s):  
Engineering Design ◽  
Design Problem ◽  
Mechanical Engineering ◽  
Engineering Students ◽  
Solution Space ◽  
New Variety ◽  
Early Stages ◽  
Correlation Analyses ◽  
Design Ideas

This paper focuses on comparing and contrasting methods for assessing the variety of a group of design ideas. Variety is an important attribute of design ideas, because it indicates the extent to which the solution space has been explored. There is a greater likelihood of successfully solving a design problem when a more diverse set of ideas is generated in the early stages of design. While there are three existing metrics for variety, it has not been established how well they correlate with each other, so it is unknown whether they provide similar assessments of variety. This uncertainty inspired our investigation of the three existing metrics and, eventually, the development of a new variety metric — all of which we compared statistically and qualitatively. In particular, 104 design ideas collected from 29 sophomore mechanical engineering students were analyzed using the existing and new variety metrics. We conducted correlation analyses to determine if the four metrics were related and to what degree. We also considered the qualitative differences among these metrics, along with where they might be used most effectively. We found varying levels of statistically significant correlations among the four metrics, indicating that they are dependent. Even so, each metric offers a unique perspective on variety and may be useful in different situations.

Multiply Separated Synthesis of Six-Link Mechanisms Using Parallel Homotopy With M-Homogenization

1998 ◽  
Author(s):  
A. K. Dhingra ◽  
M. Zhang
Keyword(s):  
Group Theory ◽  
Matrix Method ◽  
Parallel Implementation ◽  
Homotopy Methods ◽  
Numerical Work ◽  
Function Generation ◽  
Connection Machine ◽  
The Matrix ◽  
Generation Problem ◽  
Complete Solutions

Abstract This paper presents complete solutions to the function generation problem of six-link Watt and Stephenson mechanisms, with multiply separated precision positions (PP), using homotopy methods with m-homogenization. It is seen that using the matrix method for synthesis, applying m-homogeneous group theory and by defining auxiliary equations in addition to the synthesis equations, the number of homotopy paths to be tracked in obtaining all possible solutions to the synthesis problem can be drastically reduced. Numerical work dealing with the synthesis of Watt and Stephenson mechanisms for 6 and 9 multiply separated precision points is presented. For both mechanisms, it is seen that complete solutions for 6 and 9 precision points can be obtained by tracking 640 and 286,720 paths, respectively. A parallel implementation of homotopy methods on the Connection Machine on which several thousand homotopy paths can be tracked concurrently is also discussed.

An Empirical Evaluation of Novelty-SAPPhIRE Relationship

2009 ◽  
Author(s):  
V. Srinivasan ◽  
Amaresh Chakrabarti
Keyword(s):  
Conceptual Design ◽  
Strong Correlation ◽  
Design Problem ◽  
Observational Studies ◽  
Empirical Evaluation ◽  
Abstraction Level ◽  
Think Aloud Protocol ◽  
Concept Space ◽  
Abstraction Levels ◽  
The Relationship

The research shown in this paper is to check whether a framework for designing: GEMS of SAPPhIRE as req-sol, developed earlier, can support in the designing of novel concepts. This is done by asking the questions: (a) Is there a relationship between the constructs of the framework and novelty? (b) If there is a relationship, what is the degree of this relationship? A hypothesis — an increase in the size and variety of ideas used while designing should enhance the variety of concepts produced, leading to an increase in the novelty of the concept space — is developed to explain the relationship between novelty and the constructs. Eight existing observational studies of designing sessions, each involving an individual designer solving a conceptual design problem by following a think aloud protocol are used for the analysis. The hypothesis is verified empirically using the observational studies. Results also show a strong correlation between novelty and the constructs of the framework; correlation value decreases as the abstraction level of the constructs reduces, signifying the importance of using constructs at higher abstraction levels especially for novelty.

scholarly journals Imagination and the Political in Design Participation

Design Issues ◽  
2017 ◽  
Vol 33 (4) ◽  
pp. 73-82
Author(s):  
Daniel Opazo ◽  
Matías Wolff ◽  
María José Araya
Keyword(s):  
Design Problem ◽  
The Political ◽  
Binary Opposition ◽  
The Relationship

The different traditions in design participation have overlooked the relationship between imagination and the political when discussing the sources of legitimacy in participatory projects. Whether it is in architecture, planning, or design, many practitioners and scholars base their approaches to participation on what we consider an artificial exclusion between the what and the how of design, respectively understood as results and procedures. We suggest that there might be an interesting opportunity in avoiding this binary opposition, and in considering the construction of the design problem as the true what of design.

Elimination of Branch, Grashof, and Order Defects in Path-Angle Generation and Function Generation Synthesis

1979 ◽  
Vol 101 (3) ◽  
pp. 428-437 ◽  
Author(s):  
K. J. Waldron ◽  
E. N. Stevensen
Keyword(s):  
Motion Generation ◽  
Function Generation ◽  
And Function ◽  
Generation Problem

Path-Angle Generation and Function Generation synthesis problems are restated as Plane-Position (or Motion Generation) problems, enabling the use of the classical Burmester technique and recent extensions that permit the avoidance of Branch, Grashof, and Order defects. An example of the solution of a Path-Angle Generation problem is given.

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