scholarly journals A Methodology for Conceptual Design of Mechanisms by Parsing Design Specifications

2005 ◽  
Vol 127 (6) ◽  
pp. 1039-1044 ◽  
Author(s):  
Dar-Zen Chen ◽  
Wei-Ming Pai
Keyword(s):  
Conceptual Design ◽  
Design Process ◽  
Combustion Engine ◽  
Kinematic Chain ◽  
Kinematic Structure ◽  
Functional Requirements ◽  
Design Constraints ◽  
Structural Requirements ◽  
Design Specifications ◽  
Stroke Engine

In this paper, design specifications for the conceptual design of mechanisms are parsed into three coherent categories: functional requirements, structural requirements, and design constraints. Based on functional requirements, the functioning kinematic chain of a mechanism can be constructed by connecting the functioning links accordingly. From structural requirements, admissible kinematic structures are searched from the existing atlases of kinematic structures. Those admissible kinematic structures, which comprise at least one segment with the same characteristics of the functioning kinematic chain, are identified as compatible kinematic structures. Thus, feasible mechanisms that fulfill design specifications can be yielded by labeling joints in the compatible kinematic structures subject to design constraints. With this methodology, classified design specifications are used to guide designer through various stages of the conceptual design process in a systematic manner. The creation of the variable-stroke engine mechanism [Freudenstein, F., Maki, E. R., 1983, “Development of an Optimum Variable-Stroke Internal-Combustion Engine Mechanism From the Viewpoint of Kinematic Structure,” ASME J. Mech., Trans., Automat., Des., Vol. 105, pp. 259–267] is used as an illustrative example.

Integration of Conceptual Design and MOKA into CATIA v5: A Knowledge-Based Application for an Aircraft Y-Bolt Component

2012 ◽  
Vol 271-272 ◽  
pp. 974-980 ◽  
Author(s):  
Pai Zheng ◽  
Víctor Hugo Torres ◽  
José Ríos ◽  
Gang Zhao
Keyword(s):  
Conceptual Design ◽  
Design Process ◽  
Information Flow ◽  
Quality Function Deployment ◽  
Design Parameters ◽  
Knowledge Reuse ◽  
Functional Requirements ◽  
Design Information ◽  
Overall Design ◽  
Knowledge Based

The design process comprises the Conceptual Phase, the Embodiment Phase and the Detail Design Phase in which commercial PLM/CAD systems mainly support the latter ones. This situation causes the discontinuity in the overall design information flow: Customer Needs (CNs) - Functional Requirements (FRs) – Design Parameters (DPs) – Key Characteristics (KCs) – Geometric Parameters (GPs). There is also a lack of knowledge reuse in routine design process, resulting in large cost-waste of the overall design process. Aiming to enhance the continuity of the design information flow and facilitate the knowledge reuse, this paper makes use of a knowledge-based framework to integrate conceptual design tools: Quality Function Deployment (QFD), Axiomatic Design (AD), Failure Mode and Effects Analysis (FMEA) and the MOKA methodology into CATIA v5 system. A knowledge-based application (KBA) on the large aircraft y-bolt component design is presented as a case study to validate the proposed framework. The result shows how this novel integrated framework and KBA system could benefit designers in a practical way.

A Formal Approach to Specifications in Conceptual Design

1992 ◽  
Vol 114 (4) ◽  
pp. 659-666 ◽  
Author(s):  
A. Kusiak ◽  
E. Szczerbicki
Keyword(s):  
Artificial Intelligence ◽  
Key Words ◽  
Conceptual Design ◽  
Design Process ◽  
Formal Method ◽  
Functional Space ◽  
Synthesis Process ◽  
Formal Approach ◽  
Design Specifications ◽  
Design Requirements

In this paper, a methodology for the specification stage in conceptual design is presented. The specification stage provides requirements and transforms them into functions of the designed object. It occurs at the highest level of abstraction and it must provide enough information for the synthesis process where functions are transformed into design components that are further synthesized into the designed object. The proposed approach includes the following issues: specification of requirements, specification of functions, incorporation of logic into functional and requirement trees, representation of requirements-functions interaction, and optimization in the functional space. The methodology presented is illustrated with examples. Key words: design requirements, design specifications, conceptual design, design process, artificial intelligence, formal method

Development of an Optimum Variable-Stroke Internal-Combustion Engine Mechanism From the Viewpoint of Kinematic Structure

1983 ◽  
Vol 105 (2) ◽  
pp. 259-266 ◽  
Author(s):  
F. Freudenstein ◽  
E. R. Maki
Keyword(s):  
Power Plants ◽  
Combustion Engine ◽  
Mechanical Design ◽  
Structure And Function ◽  
General Nature ◽  
Search Procedure ◽  
Kinematic Structure ◽  
Prior Art ◽  
And Function ◽  
Stroke Engine

The method of separation of kinematic structure and function has been used in the development of an optimum variable-stroke engine mechanism for automotive power plants. A systematic search procedure resulted in the structures of 39 mechanisms, one of which was judged optimal (U.S. Patent No. 4,270,495—reference [13]). The prior art, as disclosed in a number of patents and other publications, was evaluated and shown to be either included in the mechanisms created in the course of the search, or deliberately excluded by the search specification. The general nature of the approach, which combines mathematical and creative approaches, is believed to be useful in mechanical design.

Functional Analysis Diagrams With the Representation of Movement Transitions

2013 ◽  
Author(s):  
Szu-Hung Lee ◽  
Pingfei Jiang ◽  
Peter R. N. Childs ◽  
Keith Gilroy
Keyword(s):  
Functional Analysis ◽  
Conceptual Design ◽  
Design Process ◽  
Mechanical Design ◽  
Functional Requirements ◽  
Design Structure ◽  
Machine Elements ◽  
Physical Elements ◽  
Types Of Information

A study on utilising a graphical interface to represent movement transmission within products has been conducted to support a creative conceptual design process that separates the consideration of functional requirements and motion requirements. In engineering design, many representations of product structure have been proposed to assist in understanding how a design is constituted. However, most of these representations demonstrate only functions and are not able to demonstrate design structure. Functional Analysis Diagrams (FAD) provides a solution for this. An FAD shows not only functions but also physical elements by the network of blocks and arrows and thus it is capable of demonstrating various types of information and the design scheme. This characteristic gives FADs an advantage for designers to combine different types of information including useful and harmful interactions to gain an overview of the design task. This study focuses on using circles instead of arrows to represent movement attributes of mechanisms and machine elements in a Kinematic Functional Analysis Diagram (KFAD) and explores methods of utilising it in mechanical design. A commercial case study of medical equipment design conducted with the assistance of KFADs and a component database, mechanism and machine elements taxonomy (MMET), is described to illustrate the process. The design outcome shows that it is feasible to follow the proposed conceptual design process. With the help of KFADs and the machine elements taxonomy to enable consideration of movements, diverse considerations and design solutions are possible.

The method for analysing and disposing of functional interaction in axiomatic design

2010 ◽  
Vol 224 (2) ◽  
pp. 401-409 ◽  
Author(s):  
C-L Cai ◽  
R-B Xiao ◽  
P Yang
Keyword(s):  
Design Process ◽  
Interaction Analysis ◽  
Axiomatic Design ◽  
Quality Loss ◽  
Functional Requirements ◽  
Functional Interaction ◽  
Critical Design ◽  
Functional Interactions ◽  
Design Specifications ◽  
Satisfaction Degree

The ill-defined interactions among functional requirements (FRs) lead to additional iterations among tasks in the design process guided by axiomatic design. This article aims to develop a structured method for analysing and disposing of functional interactions in a coupled design so as to improve the design process. First, the representation of coupled FRs is given and the notion of a critical design parameter is introduced to assist the interaction analysis between FRs. Next, the identified coupled FRs are disposed of by decoupling. The decoupling condition for coupled FRs based on design specifications is given according to the interaction analysis. To enlarge the decoupling range, the concept of satisfaction degree is introduced and a coupled design may be decoupled based on the satisfaction degree. Then, for the remaining coupled FRs after decoupling, it is a good way to adopt tearing to find a better initial ordering of iteration for speeding up the convergence of iteration in terms of the interaction analysis. An index called quality loss is introduced to aid the reordering process. Finally, two practical examples are provided to illustrate the analysis and disposal process.

Design of a Human Knee Reeducation Mechanism

2019 ◽  
Vol 11 (1) ◽  
pp. 42-53
Author(s):  
Allaoua Brahmia ◽  
Ridha Kelaiaia
Keyword(s):  
Lower Limb ◽  
Mechanical Design ◽  
Kinematic Chain ◽  
Lower Limbs ◽  
Kinematic Structure ◽  
Robotic Device ◽  
Human Knee ◽  
Kinematic Study ◽  
Rehabilitation Exercise ◽  
New Machine

Abstract To establish an exercise in open muscular chain rehabilitation (OMC), it is necessary to choose the type of kinematic chain of the mechanical / biomechanical system that constitutes the lower limbs in interaction with the robotic device. Indeed, it’s accepted in biomechanics that a rehabilitation exercise in OMC of the lower limb is performed with a fixed hip and a free foot. Based on these findings, a kinematic structure of a new machine, named Reeduc-Knee, is proposed, and a mechanical design is carried out. The contribution of this work is not limited to the mechanical design of the Reeduc-Knee system. Indeed, to define the minimum parameterizing defining the configuration of the device relative to an absolute reference, a geometric and kinematic study is presented.

scholarly journals Conceptual Design of Electromechanical Actuation Systems for Large-Sized Directional Control Valves

Actuators ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 133
Author(s):  
Tobias Vonderbank ◽  
Katharina Schmitz
Keyword(s):  
Conceptual Design ◽  
Design Process ◽  
Operating Conditions ◽  
Function Structure ◽  
Advantages And Disadvantages ◽  
Conceptual Designs ◽  
Actuation Systems ◽  
Electromechanical Actuation ◽  
Function Structures ◽  
Valve Actuation

Increasing performance in modern hydraulics is achieved by a close investigation of possible enhancements of its components. Prior research has pointed out that electromechanical actuators can form suitable alternatives to hydraulically piloted control systems. Since the requirements at these actuation systems depend on the operating conditions of the system, each actuator can be optimized to the respective hydraulic system. Considering that many different conceptual designs are suitable, the phase of conceptual design plays a decisive role during the design process. Therefore, this paper focuses on the process of developing new conceptual designs for electromechanical valve actuation systems using the method of function structures. Aiming to identify special design features, which need to be considered during the design process of electromechanical actuation systems, an exemplary actuator was designed based on the derived function structure. To highlight the potential of function structures for the development of new electromechanical valve actuation systems, two principal concepts, which allow the reduction of the necessary forces, have been developed by extending the function structure. These concepts have been experimentally investigated to identify their advantages and disadvantages.

Selecting Kinematic Structures of Parallel Manipulators Using Symmetry and Connectivity

2015 ◽  
Author(s):  
Roberto Simoni ◽  
Henrique Simas ◽  
Daniel Martins
Keyword(s):  
Conceptual Design ◽  
Kinematic Chain ◽  
Parallel Manipulators ◽  
Connectivity Matrix ◽  
Early Stages

This paper presents an application of symmetry and connectivity to select kinematic structures of parallel manipulators. One kinematic chain can originate several mechanisms and each mechanism can originate several parallel manipulators and, in early stages of conceptual design, it is difficult to decide what is the most promising one. Hunt [1] introduced the concept of connectivity and, since then, the connectivity has been used as an important parameter to select the most appropriated parallel manipulators to develop determined task. However, it is difficult to analyze non isomorphic parallel manipulators from the connectivity matrix. In this sense, in this paper, we apply symmetry to reduce the set of parallel manipulators to a manageable few with the desired connectivity. As a result, all promising parallel manipulators originating from a kinematic chain can be analyzed without isomorphisms.

scholarly journals Explicating concepts in reasoning from function to form by two-step innovative abductions

2016 ◽  
Vol 30 (2) ◽  
pp. 125-137 ◽  
Author(s):  
Ehud Kroll ◽  
Lauri Koskela
Keyword(s):  
Conceptual Design ◽  
Design Process ◽  
Abductive Reasoning ◽  
Parameter Analysis ◽  
Critical Examination ◽  
Functional Aspect ◽  
Specific Design ◽  
Design Processes ◽  
Step Process ◽  
Design Reasoning

AbstractThe mechanism of design reasoning from function to form is suggested to consist of a two-step inference of the innovative abduction type. First is an inference from a desired functional aspect to an idea, concept, or solution principle to satisfy the function. This is followed by a second innovative abduction, from the latest concept to form, structure, or mechanism. The intermediate entity in the logical reasoning, the concept, is thus made explicit, which is significant in following and understanding a specific design process, for educating designers, and to build a logic-based computational model of design. The idea of a two-step abductive reasoning process is developed from the critical examination of several propositions made by others. We use the notion of innovative abduction in design, as opposed to such abduction where the question is about selecting among known alternatives, and we adopt a previously proposed two-step process of abductive reasoning. However, our model is different in that the two abductions used follow the syllogistic pattern of innovative abduction. In addition to using a schematic example from the literature to demonstrate our derivation, we apply the model to an existing, empirically derived method of conceptual design called “parameter analysis” and use two examples of real design processes. The two synthetic steps of the method are shown to follow the proposed double innovative abduction scheme, and the design processes are presented as sequences of double abductions from function to concept and from concept to form, with a subsequent deductive evaluation step.

A model of the mechanical design process based on empirical data

1988 ◽  
Vol 2 (1) ◽  
pp. 33-52 ◽  
Author(s):  
David G. Ullman ◽  
Thomas G. Dietterich ◽  
Larry A. Stauffer
Keyword(s):  
Problem Solving ◽  
Detailed Analysis ◽  
Conceptual Design ◽  
Design Process ◽  
Empirical Data ◽  
Mechanical Design ◽  
Level Of Detail ◽  
Cad Tools ◽  
Design Alternatives ◽  
Key Features

This paper describes the task/episode accumulation model (TEA model) of non-routine mechanical design, which was developed after detailed analysis of the audio and video protocols of five mechanical designers. The model is able to explain the behavior of designers at a much finer level of detail than previous models. The key features of the model are (a) the design is constructed by incrementally refining and patching an initial conceptual design, (b) design alternatives are not considered outside the boundaries of design episodes (which are short stretches of problem solving aimed at specific goals), (c) the design process is controlled locally, primarily at the level of individual episodes. Among the implications of the model are the following: (a) CAD tools should be extended to represent the state of the design at more abstract levels, (b) CAD tools should help the designer manage constraints, and (c) CAD tools should be designed to give cognitive support to the designer.

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