A study on the grammatical construction of function structures

2005 ◽  
Vol 19 (3) ◽  
pp. 139-160 ◽  
Author(s):  
PRASANNA SRIDHARAN ◽  
MATTHEW I. CAMPBELL
Keyword(s):  
Automated Reasoning ◽  
Black Box ◽  
Graph Grammar ◽  
Functional Information ◽  
Customer Requirements ◽  
Conceptual Engineering ◽  
Grammatical Construction ◽  
Grammar Rules ◽  
Interactive User ◽  
Function Structures

Function structures are used during conceptual engineering design to transform the customer requirements into specific functional tasks. Although they are usually constructed from a well-understood black-box description of an artifact, there is no clear approach or formal set of rules that guide the creation of function structures. To remedy the unclear formation of such structures and to provide the potential for automated reasoning of such structures, a graph grammar is developed and implemented. The grammar can be used by a designer to explore various solutions to a conceptual design problem. Furthermore, the grammar aids in disseminating engineering functional information and in teaching the function structure concept to untrained engineers. Thirty products are examined as a basis for developing the grammar rules, and the rules are implemented in an interactive user environment. Experiments with student engineers and with the automated creation of function structures validate the effectiveness of the grammar rules.

scholarly journals Using a graph grammar system in the finite element method

2013 ◽  
Vol 23 (4) ◽  
pp. 839-853 ◽  
Author(s):  
Barbara Strug ◽  
Anna Paszynśka ◽  
Maciej Paszynśki ◽  
Ewa Grabska
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Graph Grammar ◽  
Graph Grammars ◽  
The Finite Element Method ◽  
Computational Mesh ◽  
Composite Graph ◽  
Initial Mesh ◽  
Grammar Rules ◽  
Element Method

Abstract The paper presents a system of Composite Graph Grammars (CGGs)modelling adaptive two dimensional hp Finite Element Method (hp-FEM) algorithms with rectangular finite elements. A computational mesh is represented by a composite graph. The operations performed over the mesh are defined by the graph grammar rules. The CGG system contains different graph grammars defining different kinds of rules of mesh transformations. These grammars allow one to generate the initial mesh, assign values to element nodes and perform h- and p-adaptations. The CGG system is illustrated with an example from the domain of geophysics.

Framework for Generating Modularized Product Designs With Assembly and Variety Considerations

2008 ◽  
Author(s):  
Saraj Gupta ◽  
Gu¨l E. Okudan
Keyword(s):  
Conceptual Design ◽  
Personal Experience ◽  
Graph Grammar ◽  
Design Stage ◽  
Design For Assembly ◽  
Computational Tools ◽  
Design Alternatives ◽  
Grammar Rules ◽  
Design For Variety ◽  
Two Alternatives

Conceptual design is found to be the most ambiguous and creative phase of design. There exist only a few computational tools that aid designers at conceptual design stage, and mostly designers rely on personal experience or experience of coworkers to generate quality designs. The proposed framework aims at generating robust computerized conceptual designs by incorporating Modularity, Design for Assembly (DFA) and Design for Variety (DFV) principles at the conceptual stage. Conceptual design alternatives obtained from the proposed framework are ranked based on minimum assembly time, and are composed of modules in a way that future changes in customer needs are satisfied only by replacing certain modules. The framework involves searching a design repository of components by using functional-basis and pre-defined graph grammar rules, to generate all possible conceptual design alternatives. These design alternatives are ranked and filtered using a DFA index, and top two alternatives are selected. Selected designs are modularized and filtered using a DFV index to obtain the best design alternative. This paper provides a detailed discussion of the framework obtained by amalgamating Modularity, DFA, and DFV. Working of the proposed framework is demonstrated with the help of an electronic toothbrush design example.

Assembly and Variety Considerations During Conceptual Design

2008 ◽  
Author(s):  
Saraj Gupta ◽  
Gu¨l E. Okudan
Keyword(s):  
Conceptual Design ◽  
Personal Experience ◽  
Graph Grammar ◽  
Design Stage ◽  
Computational Tools ◽  
Design Alternatives ◽  
Grammar Rules ◽  
Design For Variety ◽  
Electromechanical Product ◽  
Two Alternatives

Foremost step in the development of any electromechanical product is its design, and conceptual design is the most ambiguous and creative phase of design. There exist only a few computational tools that aid designers at conceptual design stage, and mostly designers rely on personal experience or experience of co-workers to generate quality designs. The proposed framework aims at generating robust computerized conceptual designs by incorporating Modularity, Design for Assembly (DFA) and Design for Variety (DFV) principles at the conceptual stage. Conceptual design alternatives obtained from the proposed framework are ranked based on minimum assembly time, and are composed of modules in a way that future changes in customer needs are satisfied only by replacing certain modules. The framework involves searching a design repository of components by using functional-basis and pre-defined graph grammar rules, to generate all possible conceptual design alternatives. These design alternatives are ranked and filtered using a DFA index, and top two alternatives are selected. Selected designs are modularized and filtered using a DFV index to obtain the best design alternative. This paper provides a detailed discussion of the proposed framework, and its working is illustrated through the design of a mounting system for holding a Variable Message Sign (VMS).

scholarly journals Comparing function structures and pruned function structures for market price prediction: An approach to benchmarking representation inferencing value

2017 ◽  
Vol 31 (4) ◽  
pp. 550-566 ◽  
Author(s):  
Amaninder Singh Gill ◽  
Joshua D. Summers ◽  
Cameron J. Turner
Keyword(s):  
Predictive Model ◽  
Predictive Power ◽  
Market Price ◽  
Level Of Detail ◽  
Market Values ◽  
Price Prediction ◽  
And Topology ◽  
Grammar Rules ◽  
Model Set ◽  
Function Structures

AbstractBenchmarking function modeling and representation approaches requires a direct comparison, including the inferencing support by the different approaches. To this end, this paper explores the value of a representation by comparing the ability of a representation to support reasoning based on varying amounts of information stored in the representational components of a function structure: vocabulary, grammar, and topology. This is done by classifying the previously developed functional pruning rules into vocabulary, grammatical, and topological classes and applying them to function structures available from an external design repository. The original and pruned function structures of electromechanical devices are then evaluated for how accurately market values can be predicted using the graph complexity connectivity method. The accuracy is found to be inversely related to the amount of information and level of detail. Applying the topological rule does not significantly impact the predictive power of the models, while applying the vocabulary rules and the grammar rules reduces the accuracy of the predictions. Finally, the least predictive model set is that which had all rules applied. In this manner, the value of a representation to predict or answer questions is quantified.

Impact of Level of Detail and Information Content on Accuracy of Function Structure-Based Market Price Prediction Models

2016 ◽  
Author(s):  
Amaninder Singh Gill ◽  
Joshua D. Summers ◽  
Cameron J. Turner
Keyword(s):  
Prediction Models ◽  
Market Price ◽  
Level Of Detail ◽  
Research Approach ◽  
Function Structure ◽  
Amount Of Information ◽  
Market Values ◽  
Grammar Rules ◽  
Model Set ◽  
Function Structures

This paper explores the amount of information stored in the representational components of a function structure: vocabulary, grammar, and topology. This is done by classifying the previously developed functional composition rules into vocabulary, grammatical, and topological classes and applying them to function structures available in an external design repository. The pruned function structures of electromechanical devices are then evaluated for how accurately market values can be predicted using graph complexity connectivity method. The accuracy is inversely with amount of information and level of detail. Applying the topological rule does not significantly impact the predictive power of the models, while applying the vocabulary rules and the grammar rules reduce the accuracy of the predictions. Finally, the least predictive model set is that which had all rules applied. In this manner, the value of a representation to predict or answer questions is quantified through this research approach.

An Automated Graph Grammar Based Tool to Automatically Generate System Bond Graphs for Dynamic Analysis

2016 ◽  
Author(s):  
Daniel Grande ◽  
Felice Mancini ◽  
Pradeep Radhakrishnan
Keyword(s):  
Dynamic Analysis ◽  
Bond Graph ◽  
Graph Grammar ◽  
Search Process ◽  
Bond Graphs ◽  
System Components ◽  
Grammar Rules ◽  
Algorithmic Search ◽  
Representation Scheme ◽  
Automated Tool

This paper presents a graph grammar based automated tool that can generate bond graphs of various systems for dynamic analysis. A generic graph grammar based representation scheme has been developed for different system components and bond graph elements. Using that representation, grammar rules have been developed that enable interpreting a given system and generating bond graph through an algorithmic search process. Besides, the paper also demonstrates the utility of the proposed tool in classrooms to enhance value in bond graph based system dynamics education. The underlying technique, various examples and benefits of this automated tool will be highlighted.

Transformation of an EGT Grammar: New Grammar, New Designs

2004 ◽  
Vol 126 (4) ◽  
pp. 753-756 ◽  
Author(s):  
Xin Li and ◽  
Linda C. Schmidt ◽  
Weidong He, ◽  
Lixing Li, and ◽  
Yuanmei Qian
Keyword(s):  
Gear Train ◽  
Graph Grammar ◽  
Design Alternatives ◽  
Epicyclic Gear ◽  
Grammar Rules ◽  
The Creation ◽  
Selection Of

True design with grammars lies in the creation of the grammar rules, not in the application of the rules to generate design alternatives. Existing grammars can be modified to describe new languages of designs [1–4]. Studying an epicyclic gear train graph grammar leads to purposeful relaxation of grammar rules and subsequent discovery of new designs. A revised new EGT grammar is presented, which is designed to generate a wider selection of valid EGTs.

scholarly journals Including Functional Models of Biological Phenomena as Design Stimuli

2007 ◽  
Author(s):  
V. Vakili ◽  
I. Chiu ◽  
L. H. Shu ◽  
D. A. McAdams ◽  
R. B. Stone
Keyword(s):  
Analogical Reasoning ◽  
Graph Grammar ◽  
Leaf Abscission ◽  
Visual Aids ◽  
Micro Assembly ◽  
Biological Phenomena ◽  
Functional Models ◽  
Grammar Rules ◽  
Biological Domain ◽  
Assembly Problem

This work explores the representation of biological phenomena as stimuli to designers for biomimetic design. We describe a study where participants were asked to solve a micro-assembly problem given a set of biological representations of leaf abscission for inspiration. The visual aids presented to the designers are investigated, and the use of functional models of biological phenomena in particular is critiqued. The designs resulting from the study are classified and theories drawn as to possible influences of the biological representations. Observations, retrospective conversations with participants, and analogical reasoning classifications are used to determine positive qualities as well as areas for improvement in representation of the biological domain. Findings suggest that designers need an explicit list of all possible inherent biological strategies, previously extracted using function structures with objective graph grammar rules. Challenges specific to this type of study are discussed, and possible improvement of representative aids are outlined.

Automated Synthesis of Passive Dynamic Brachiating Robots Using a Simulation-Driven Graph Grammar Method

2017 ◽  
Vol 139 (9) ◽  
Author(s):  
Fritz Stöckli ◽  
Kristina Shea
Keyword(s):  
Dynamic Simulation ◽  
Dynamic Systems ◽  
Computational Design ◽  
Automated Design ◽  
Graph Grammar ◽  
Robotic Systems ◽  
Design Synthesis ◽  
Continuous Contact ◽  
Cyclic Motion ◽  
Grammar Rules

Passive dynamic systems have the advantage over conventional robotic systems that they do not require actuators and control. Brachiating, in particular, involves the swinging motion of an animal from one branch to the next. Such systems are usually designed manually by human designers and often are bio-inspired. However, a computational design approach has the capability to search vast design spaces and find solutions that go beyond those possible by manual design. This paper addresses the automated design of passive dynamic systems by introducing a graph grammar-based method that integrates dynamic simulation to evaluate and evolve configurations. In particular, the method is shown to find different, new solutions to the problem of the design of two-dimensional passive, dynamic, continuous contact, brachiating robots. The presented graph grammar rules preserve symmetry among robot topologies. A separation of parametric multi-objective optimization and topologic synthesis is proposed, considering four objectives: number of successful swings, deviation from cyclic motion, required space, and number of bodies. The results show that multiple solutions with varying complexity are found that trade-off cyclic motion and the space required. Compared to research on automated design synthesis of actuated and controlled robotic systems, this paper contributes a new method for passive dynamic systems that integrates dynamic simulation.

scholarly journals A Graph Grammar Based Approach to Automated Manufacturing Planning

2012 ◽  
Author(s):  
Wentao Fu ◽  
Ata A. Eftekharian ◽  
Pradeep Radhakrishnan ◽  
Matthew I. Campbell ◽  
Christian Fritz
Keyword(s):  
Graph Grammar ◽  
Manufacturing Planning ◽  
Operation Rules ◽  
Solid Models ◽  
Arbitrary Geometries ◽  
Grammar Rules ◽  
The Face ◽  
Complex Engineering ◽  
Effectiveness And Efficiency ◽  
Machining Operations

In this paper, a new graph grammar representation is proposed to reason about the manufacturability of solid models. The knowledge captured in the graph grammar rules serves as a virtual machinist in its ability to recognize arbitrary geometries and match them to various machine operations. Firstly, a given part is decomposed into multiple sub-volumes, where each sub-volume is assumed to be machined in one operation or to be non-machinable. The decomposed part is converted into a graph so that graph grammar rules can determine the machining details. For each operation, rules determine the face on the part that the tool enters, the type of tools used, the type of machine used, and how the part is fixed within the machine. A candidate plan is a feasible sequence of all of the necessary machining operations needed to manufacture this part. If a given geometry is not machinable, the rules will fail to find operations for all of the partitions. As a result of this representation, designers can quickly get insights into how a part can be made and how it can be improved (e.g. change features to reduce time and cost). A variety of tests of this algorithm on both simple and complex engineering parts show its effectiveness and efficiency.

Sign in / Sign up

Export Citation Format

Share Document