IGES Standard Protocol for Feature Recognition CAD System

Author(s):  
Emad Abouel Nasr ◽  
Ali Kamrani
Author(s):  
A. Z. Qamhiyah ◽  
B. Benhabib ◽  
R. D. Venter

Abstract Many of today’s concurrent product-development cycles depend on the utilization of intelligent Computer-Aided Design (CAD) systems. Thus, it would be essential to provide CAD users with effective means for interacting with the CAD system and its database. This paper addresses the development of a boundary-based coding procedure for CAD models. Coding the geometric and processing characteristics of objects, based on their CAD model representation, has been long recognized as an effective approach that allows convenient design retrieval on the one hand and process-planning automation on the other. Our work is based on the assumption that form features are recognizable and extractable from the CAD model by current feature-recognition, feature extraction and feature-based-design approaches. The coding procedure is applicable to the boundary representation of the object and its extracted form features.


2015 ◽  
Vol 85 (9-12) ◽  
pp. 2577-2587 ◽  
Author(s):  
Qiao Guo ◽  
Hongtao Tang ◽  
Shunsheng Guo ◽  
Yibing Li ◽  
Jinting Zhang

Author(s):  
Nagesh Belludi ◽  
Derek Yip-Hoi

Several CAD system independent feature recognition techniques have been developed to drive manufacturing applications. Commercial implementations of these techniques require translating CAD models using STEP or other neutral file formats. With large CAD models found in some application domains; e.g., powertrain machining, corresponding STEP files are also large. This leads to large processing times. Another approach is to use lightweight formats such as STL or VRML. Here, complete & accurate parameter extraction is difficult because these formats approximate surfaces as tessellations. This paper discusses a new methodology for feature recognition, in which a VRML file is used for feature identification. To some extent, parameters of faces with simple surface-types are recovered from the tessellated model. If identified features consist of faces whose parameters are not recovered from the tessellated model, a partial STEP file translation is used for extracting exact parameters. This CAD system independent algorithmic development and implementation reduces the amount of data exported to neutral files, thus leading to more efficient feature recognition.


Author(s):  
Marcus Sandberg ◽  
Tobias Larsson

Automating redesign is an approach for engineering designers to prevent design related manufacturability problems in early product development and thus reduce costly design iterations. A vast amount of work exists, with most research findings seemingly staying within the research community rather than finding its way into use in industrial settings where research issues have often evolved from the concerned applied research. The aim of this paper is to present an approach with industrial implementation potential regarding automating redesign of sheet-metal components in early product development to avoid manufacturing problems due to design flaws and non-optimal designs. Geometry, generated by a knowledge-based engineering (KBE) system, gives input to the case-based reasoning (CBR) governed manufacturing planning. If geometry is found non-manufacturable or enhancement of already manufacturable geometry is possible, the CBR system will suggest redesign actions to resolve the problem. CBR extends the capabilities of the rule-based KBE-system by enabling plan-based evaluation. The approach has the potential for industrial implementation, since KBE is often closely coupled to an industrial CAD-system, hence enabling technology is at the industry. Also, combining KBE and CBR reduces the coding effort compared to coding the whole design support with CBR, as feature recognition is simplified by means of KBE. A case study of development of sheet-metal manufactured parts at a Swedish automotive industry partner presents the method in use. As it is shown that redesign can be automated for sheet-metal parts there is a potential for reducing costly design and manufacturing iterations.


Author(s):  
Xun Xu

Conventional CAD models only provide pure geometry and topology for mechanical designs such as vertices, edges, faces, simple primitives, and the relationship among them. Feature recognition is then required to interpret this low-level part information into high-level and domain-specific features such as machining features. Over the years, CAD has been undergoing fundamental changes toward the direction of feature-based design or design by features. Commercial implementations of FBD technique became available in the late 1980’s. One of the main benefits of adopting feature- based approach is the fact that features can convey and encapsulate designers’ intents in a natural way. In other words, the initial design can be synthesized quickly from the high-level entities and their relations, which a conventional CAD modeller is incapable of doing. However, such a feature-based design system, though capable of generating feature models as its end result, lacks the necessary link to a CAPP system, simply because the design features do not always carry the manufacturing information which is essential for process planning activities. This type of domain-dependent nature has been elaborated on in the previous chapter. In essence, feature recognition has become the first task of a CAPP system. It serves as an automatic and intelligent interpreter to link CAD with CAM, regardless of the CAD output being a pure geometric model or a feature model from a FBD system. To be specific, the goal of feature recognition systems is to bridge the gap between a CAD database and a CAPP system by automatically recognizing features of a part from the data stored in the CAD system, and based on the recognized features, to drive the CAPP system which produces process plans for manufacturing the part. Human interpretation of translating CAD data into technological information required by a CAPP system is thus minimized if not eliminated.


2021 ◽  
Vol 2021 ◽  
pp. 1-28
Author(s):  
Ahsan Bin Tufail ◽  
Yong-Kui Ma ◽  
Mohammed K. A. Kaabar ◽  
Francisco Martínez ◽  
A. R. Junejo ◽  
...  

Deep learning (DL) is a branch of machine learning and artificial intelligence that has been applied to many areas in different domains such as health care and drug design. Cancer prognosis estimates the ultimate fate of a cancer subject and provides survival estimation of the subjects. An accurate and timely diagnostic and prognostic decision will greatly benefit cancer subjects. DL has emerged as a technology of choice due to the availability of high computational resources. The main components in a standard computer-aided design (CAD) system are preprocessing, feature recognition, extraction and selection, categorization, and performance assessment. Reduction of costs associated with sequencing systems offers a myriad of opportunities for building precise models for cancer diagnosis and prognosis prediction. In this survey, we provided a summary of current works where DL has helped to determine the best models for the cancer diagnosis and prognosis prediction tasks. DL is a generic model requiring minimal data manipulations and achieves better results while working with enormous volumes of data. Aims are to scrutinize the influence of DL systems using histopathology images, present a summary of state-of-the-art DL methods, and give directions to future researchers to refine the existing methods.


2011 ◽  
Vol 346 ◽  
pp. 294-300 ◽  
Author(s):  
Qing Ming Fan ◽  
Yan Cao ◽  
Hong Jun Liu

According to the engineering demands of the manufacturability evaluation, the Aero engine blade part information model built up based on the generalized feature and STEP standard, and based on the secondary development of UG software, a CAD system based on features is realized. The system can realize automatic feature recognition. Based on the part information model that has been built up, the system can generate STEP document automatically, can provide various blade part information for the subsequent manufacturability evaluation of the design. This helps to realize the integration and parallel of CAD and the subsequent process. The CAD/CPAPP/DFM information integration can be realized by using the blade part information that has been built up.


2017 ◽  
Vol 22 (3) ◽  
pp. 285
Author(s):  
C. F. Tan ◽  
N. Ismail ◽  
S.V. Wong ◽  
S. Sulaiman ◽  
M.R. Osman

This paper describes the development of Hole Recognition System (HRS) for Computer-Aided Process Planning (CAPP) using a neutral data format produced by CAD system. The geometrical data of holes is retrieved from STandard for the Exchange of Product model data (STEP). Rule-based algorithm is used during recognising process. Current implementation of feature recognition is limited to simple hole feat ures. Test results are presented to demonstrate the capabilities of the feature recognition algorithm.


2020 ◽  
pp. 1-12
Author(s):  
Li Dongmei

English text-to-speech conversion is the key content of modern computer technology research. Its difficulty is that there are large errors in the conversion process of text-to-speech feature recognition, and it is difficult to apply the English text-to-speech conversion algorithm to the system. In order to improve the efficiency of the English text-to-speech conversion, based on the machine learning algorithm, after the original voice waveform is labeled with the pitch, this article modifies the rhythm through PSOLA, and uses the C4.5 algorithm to train a decision tree for judging pronunciation of polyphones. In order to evaluate the performance of pronunciation discrimination method based on part-of-speech rules and HMM-based prosody hierarchy prediction in speech synthesis systems, this study constructed a system model. In addition, the waveform stitching method and PSOLA are used to synthesize the sound. For words whose main stress cannot be discriminated by morphological structure, label learning can be done by machine learning methods. Finally, this study evaluates and analyzes the performance of the algorithm through control experiments. The results show that the algorithm proposed in this paper has good performance and has a certain practical effect.


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