The Design Exemplar: A New Data Structure for Embodiment Design Automation

2004 ◽  
Vol 126 (5) ◽  
pp. 775-787 ◽  
Author(s):  
Joshua D. Summers ◽  
Bernie Bettig ◽  
Jami J. Shah

A key issue in developing new intelligent computer aided design and manufacturing tools (CAD/CAM) is knowledge representation. Engineering knowledge has been represented in many forms, such as rule sets, design procedures, features, frames, and semantic networks. Some of these are domain dependent, some are query dependent, and some require specialized inferencing engines or solving algorithms, thus providing a severe limitation for exchange and re-use of design knowledge. A standard representation structure that is capable of encapsulating different types of knowledge would be a useful tool. The design exemplar provides a standard representation of mechanical engineering design problem knowledge based upon a canonically derived set of entities and relationships. The data structure of the design exemplar facilitates four basic design tasks: pattern matching, property extraction, design validation, and change propagation. This paper shows that it is possible to map the design exemplar to other representations (procedures, rules, and features). The concept of integrating atomic design exemplars into composite networks for performing complex design tasks is also introduced as a tool for developing and applying the design exemplar in engineering design automation.

Author(s):  
Mohamed Galaleldin ◽  
Hanan Anis

The primary purpose of this study is to explore the relationship between engineering students’ year of study, gender and grit level. This study also aims to assess whether there is any relationship between students’ peer assessment scores in a collaborative project-based learning course and their goal orientation — either towards performance goals or learning goals — and their grit level. The study design is a quasi-experimental design, and the methods used in this study are quantitative. Student grit level was measured using a 12-item scale. The questionnaire was administered in three engineering design courses at different levels of study. The first course is an introduction to engineering design course for firstyear engineering and computer sciences students; the second is an introduction to engineering design course for second-year engineering and computer science students; and the third is a computer-aided design/computer-aidedmanufacturing (CAD/CAM) engineering design capstone course for fourth-year mechanical engineering students.  Data collection occurred during the fall semester of 2018- 2019 academic year. Students’ grit level was not found to be a predictor of students’ peer assessment scores, although their goal orientation predicted their level of contribution to their team project.  


Author(s):  
Christian Johansson

AbstractIn the production of automotive body components, fixtures are an important part of the ongoing work on geometrical assurance. The fixture is uniquely defined for each component, and the design and configuration of these are time-consuming and takes a lot of effort. The objective with this paper is to explore the use of a design automation approach and application to semi-automate the configuration process of the fixture product. The paper presents an approach to automate the configuration of the fixtures in a flexible way, by reverse engineering the configuration of the fixture product from a generic blueprint that represents the expected outcome of the process, using a knowledge-based engineering approach applied to a computer aided design (CAD) environment. A reverse-engineered design automation toolbox for a CAD-software is developed. The toolbox is developed to lead a user through the configuration process, in the way that the experts want it done, end-to-end, making use of some unconventional solutions from a design automation perspective.


Author(s):  
John R. Goulding ◽  
Hormoz Zarefar

Abstract Computer Aided Design and Computer Aided Manufacturing (CAD/CAM) software programs are used in mechanical engineering industries to reduce the time it takes to draft, simulate, machine, and plan a product. When knowledge-based expert rules, equations, and proprietary languages extend CAD/CAM software, previously designed mechanisms can be scaled to satisfy new design requirements in the shortest time. Two major drawbacks exist in current technology. First, embedded design alternatives needed by design engineers during the product conception and rework stages are lacking. Second, an operator is required who has a thorough understanding of the intended design and the how-to expertise needed to create and optimize the design alternatives. The focus of our research and development was to automate the intellectual operations; e.g., questioning, identifying, selecting, and coordinating the design process. A robust system emerged which: 1. Selects the best mechanisms necessary to design a power transmission device from proven solutions. 2. Aids the inexperienced operator in developing complex design solutions. 3. Provides design alternatives which add back-to-the-drawing-board capabilities to knowledge-based mechanical power transmission CAD programs.


Author(s):  
Jyh-Huei Chern

Abstract Today, engineering designs are tackling projects of increasing complexity and cost. The constraints are getting more complex, there are new materials and processes to exploit and stricter regulations and legal requirements to satisfy. Making products more quickly and efficiently is even more important in these times of increasing economic competition. Over recent years, use of computer tools in the design-analysis-manufacture stages has led to decreased lead times and reduced product costs. In particular, in the engineering design process, it has become clear that more extensive computer based support tools would result in greater gains. These include tools that help the designer maintain consistency in the design representation, help in documentation of information such as design intent, perform knowledge based manufacturing analysis and help in the generation of intelligent manufacturing plans. Progress has been made in the representation of design entities, as can be seen, for example, in geometric modeling. However, as this article point out, the techniques and methodologies underlying current Computer-Aided Design (CAD) systems are an insufficient basis for realizing automation of the engineering design process. This article proposes that an integration of Artificial Intelligence (AI) techniques with geometric modeling systems can better meet the requirements of Computer-Aided Engineering (CAE) design practice.


Author(s):  
Philipp Ganser ◽  
Markus Landwehr ◽  
Sven Schiller ◽  
Christopher Vahl ◽  
Sebastian Mayer ◽  
...  

Abstract Early and efficient harmonization between product design and manufacturing represents one of the most challenging tasks in engineering. Concepts such as simultaneous engineering aim for a product creation process, which addresses both, functional requirements as well as requirements from production. However, existing concepts mostly focus on organizational tasks and heavily rely on the human factor for the exchange of complex information across different domains, organizations or systems. Nowadays product and process design make use of advanced software tools such as computer-aided design, manufacturing and engineering systems (CAD/CAM/CAE). Modern systems already provide a seamless integration of both worlds in a single digital environment to ensure a continuous workflow. Yet, for the holistic harmonization between product and process design, a complete and data consistent digital twin, an adaptation of product and process design for a balanced functionality and manufacturability, as well as systematic long-term data analytics across different product and process designs are missing. This paper presents an exploration concept which couples product design (CAD), process design (CAM), process simulation (CAE) and process adaptation in a single software system. The approach provides insights into correlations and dependencies between input parameters of product/process design and the process output. The insights potentially allow for a knowledge-based adaptation, tackling well-known optimization issues such as parameter choice or operation sequencing. First results are demonstrated using the example of a blade integrated disk (blisk).


Author(s):  
A. N. Bozhko

Computer-aided design of assembly processes (Computer aided assembly planning, CAAP) of complex products is an important and urgent problem of state-of-the-art information technologies. Intensive research on CAAP has been underway since the 1980s. Meanwhile, specialized design systems were created to provide synthesis of assembly plans and product decompositions into assembly units. Such systems as ASPE, RAPID, XAP / 1, FLAPS, Archimedes, PRELEIDES, HAP, etc. can be given, as an example. These experimental developments did not get widespread use in industry, since they are based on the models of products with limited adequacy and require an expert’s active involvement in preparing initial information. The design tools for the state-of-the-art full-featured CAD/CAM systems (Siemens NX, Dassault CATIA and PTC Creo Elements / Pro), which are designed to provide CAAP, mainly take into account the geometric constraints that the design imposes on design solutions. These systems often synthesize technologically incorrect assembly sequences in which known technological heuristics are violated, for example orderliness in accuracy, consistency with the system of dimension chains, etc.An AssemBL software application package has been developed for a structured analysis of products and a synthesis of assembly plans and decompositions. The AssemBL uses a hyper-graph model of a product that correctly describes coherent and sequential assembly operations and processes. In terms of the hyper-graph model, an assembly operation is described as shrinkage of edge, an assembly plan is a sequence of shrinkages that converts a hyper-graph into the point, and a decomposition of product into assembly units is a hyper-graph partition into sub-graphs.The AssemBL solves the problem of minimizing the number of direct checks for geometric solvability when assembling complex products. This task is posed as a plus-sum two-person game of bicoloured brushing of an ordered set. In the paradigm of this model, the brushing operation is to check a certain structured fragment for solvability by collision detection methods. A rational brushing strategy minimizes the number of such checks.The package is integrated into the Siemens NX 10.0 computer-aided design system. This solution allowed us to combine specialized AssemBL tools with a developed toolkit of one of the most powerful and popular integrated CAD/CAM /CAE systems.


2013 ◽  
Vol 1 (1) ◽  
pp. 158-178
Author(s):  
Urcun John Tanik

Cyberphysical system design automation utilizing knowledge based engineering techniques with globally networked knowledge bases can tremendously improve the design process for emerging systems. Our goal is to develop a comprehensive architectural framework to improve the design process for cyberphysical systems (CPS) and implement a case study with Axiomatic Design Solutions Inc. to develop next generation toolsets utilizing knowledge-based engineering (KBE) systems adapted to multiple domains in the field of CPS design automation. The Cyberphysical System Design Automation Framework (CPSDAF) will be based on advances in CPS design theory based on current research and knowledge collected from global sources automatically via Semantic Web Services. A case study utilizing STEM students is discussed.


Science Scope ◽  
2017 ◽  
Vol 041 (01) ◽  
Author(s):  
Nicholas Garafolo ◽  
Nidaa Makki ◽  
Katrina Halasa ◽  
Wondimu Ahmed ◽  
Kristin Koskey ◽  
...  

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 959
Author(s):  
Verónica Rodríguez ◽  
Celia Tobar ◽  
Carlos López-Suárez ◽  
Jesús Peláez ◽  
María J. Suárez

The aim of this study was to investigate the load to fracture and fracture pattern of prosthetic frameworks for tooth-supported fixed partial dentures (FPDs) fabricated with different subtractive computer-aided design and computer-aided manufacturing (CAD-CAM) materials. Materials and Methods: Thirty standardized specimens with two abutments were fabricated to receive three-unit posterior FDP frameworks with an intermediate pontic. Specimens were randomly divided into three groups (n = 10 each) according to the material: group 1 (MM)—milled metal; group 2 (L)—zirconia; and group 3 (P)—Polyetheretherketone (PEEK). The specimens were thermo-cycled and subjected to a three-point bending test until fracture using a universal testing machine (cross-head speed: 1 mm/min). Axial compressive loads were applied at the central fossa of the pontics. Data analysis was made using one-way analysis of variance, Tamhane post hoc test, and Weibull statistics (α = 0.05). Results: Significant differences were observed among the groups for the fracture load (p < 0.0001). MM frameworks showed the highest fracture load values. The PEEK group registered higher fracture load values than zirconia samples. The Weibull statistics corroborated these results. The fracture pattern was different among the groups. Conclusions: Milled metal provided the highest fracture load values, followed by PEEK, and zirconia. However, all tested groups demonstrated clinically acceptable fracture load values higher than 1000 N. PEEK might be considered a promising alternative for posterior FPDs.


Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3819
Author(s):  
Ting-Hsun Lan ◽  
Yu-Feng Chen ◽  
Yen-Yun Wang ◽  
Mitch M. C. Chou

The computer-aided design/computer-aided manufacturing (CAD/CAM) fabrication technique has become one of the hottest topics in the dental field. This technology can be applied to fixed partial dentures, removable dentures, and implant prostheses. This study aimed to evaluate the feasibility of NaCaPO4-blended zirconia as a new CAD/CAM material. Eleven different proportional samples of zirconia and NaCaPO4 (xZyN) were prepared and characterized by X-ray diffractometry (XRD) and Vickers microhardness, and the milling property of these new samples was tested via a digital optical microscope. After calcination at 950 °C for 4 h, XRD results showed that the intensity of tetragonal ZrO2 gradually decreased with an increase in the content of NaCaPO4. Furthermore, with the increase in NaCaPO4 content, the sintering became more obvious, which improved the densification of the sintered body and reduced its porosity. Specimens went through milling by a computer numerical control (CNC) machine, and the marginal integrity revealed that being sintered at 1350 °C was better than being sintered at 950 °C. Moreover, 7Z3N showed better marginal fit than that of 6Z4N among thirty-six samples when sintered at 1350 °C (p < 0.05). The milling test results revealed that 7Z3N could be a new CAD/CAM material for dental restoration use in the future.


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