工艺规划与CADCAM数控机床系统集成

1、A feasible approach to the integration of CAD and CAPP综合方法与总体思路Although current CAD systems are declared to be feature-based, in fact, the so-called feature is just a modeling macro or menu name such as Protrusion, Revolution, Cutout, Block, etc., instead of a design feature or manufacturing feature

2、 in accordance with engineering practice. Consequently, product model data insufficiency and incompatibility between varieties of application systems are still the major barriers to system integration, especially the integration of design and process planning. This paper proposes a practical solutio

3、n for a bi-directional integration of CAD and CAPP on the platform of commercial CAD systems. The key techniques such as feature recognition and conversion, feature parameter and constraint extraction, feature tree reconstruction, technical information processing, process planning, automatic process

4、 drawing marking and 3D material stock CAD model generating are discussed. And the extracted features and their related technical information and knowledge are encapsulated together with the geometry-oriented CAD model to form an integrated product information model to facilitate effective integrati

5、on with the downstream activities. The integrated CAD/CAPP system is implemented on a commercial CAD package, UGS/SolidEdge. A case study and industry implementation illustrate the feasibility of the approach proposed.Article Outline1. Introduction2. Related research work and review 2.1. Feature rec

6、ognition and technical information processing2.2. Process planning2.3. System integration3. The proposed methodology 3.1. System architecture3.2. Information integration3.3. Function model4. Feature recognition and conversion 4.1. Feature recognition and conversion algorithm4.2. Manufacturing featur

7、e recognition and reconstruction5. Process planning 5.1. Process decision-making5.2. Process selection and operation sequencing optimization6. Stock model and process drawing generation 6.1. Stock model generating6.2. Process drawing generating6.3. Other aided functions7. ConclusionsReferencesA fram

8、ework for extending computer aided process planning to include business activities and computer aided design and manufacturing (CAD/CAM) data retrieval工艺过程规划与CAD/CAM 制造单元的数据提取与互换框架（包含商业运作过程中的产品修改过程）Computer aided process planning (CAPP) systems have had limited success in integrating business functi

9、ons and product manufacturing due to the inaccessibility and incompatibility of information residing in proprietary software. While large companies have developed or purchased complex order management and engineering applications, smaller manufacturers continue to use semi-automated and manual metho

10、ds for managing information throughout the lifecycle of each new product and component. There is a need for reconfigurable and reprogrammable systems that combine advances in computer aided design (CAD/Computer Aided Manufacturing (CAM) technology and intelligent machining with product data manageme

11、nt for documentation and cost control. The goal of this research is to demonstrate an architecture in which customer service, CAPP and a costing methodology known as activity based costing (ABC) are incorporated into a single system, thereby allowing companies to monitor and study how expenditures a

12、re incurred and which resources are being used by each job. The material presented in this paper is the result of a two year university and industry sponsored research project in which professors and students at the Costa Rica Institute of Technology developed a software application for FEMA Industr

13、ial S.A., a local machining and fabrication shop with sixty five employees and both conventional and CNC capabilities. The final results represent not only a significant contribution to local industry and to the students education but, also to the continuing growth of CAPP. Implementing better decis

14、ion making tools and standardizing transactions in digital format would reduce the workload on critical personnel and archive valuable knowledge for analyzing company methods and expertise.Article Outline1. Introduction2. Background information 2.1. Review of existing work in computer aided process

15、planning (CAPP)2.2. Activity based costing (ABC) methodology2.3. Application programming interface (API)3. Industry evaluation and company selection 3.1. Industry study details3.2. Company selection4. System design and functionality 4.1. Graphical user interface (GUI)4.2. Description of modules5. Ca

16、se study6. Results of implementation phase7. ConclusionsAcknowledgementsReferencesApplication of genetic algorithm to computer-aided process planning in preliminary and detailed planning工艺过程规划与工艺细节设计的神经网络算法Computer-aided process planning (CAPP) is an important interface between computer-aided design

17、 (CAD) and computer-aided manufacturing (CAM) in the computer integrated manufacturing (CIM) environment. A good process plan of a part is built up based on two elements: (1) optimized sequence of the operations of the part; and (2) optimized selection of the machine, cutting tool and tool access di

18、rection (TAD) for each operation. On the other hand, two levels of planning in the process planning is suggested: (1) preliminary and (2) secondary and detailed planning. In this paper for the preliminary stage, the feasible sequences of operations are generated based on the analysis of constraints

19、and using a genetic algorithm (GA). Then in the detailed planning stage, using a genetic algorithm again which prunes the initial feasible sequences, the optimized operations sequence and the optimized selection of the machine, cutting tool, and TAD for each operation are obtained. By applying the p

20、roposed GA in two levels of planning, the CAPP system can generate optimal or near-optimal process plans based on a selected criterion. A number of case studies are carried out to demonstrate the feasibility and robustness of the proposed algorithm. This algorithm performs well on all the test probl

21、ems, exceeding or matching the solution quality of the results reported in the literature for most problems. The main contribution of this work is to emerge the preliminary and detailed planning, implementation of compulsive and additive constraints, optimization sequence of the operations of the pa

22、rt, and optimization selection of machine, cutting tool and TAD for each operation using the proposed GA, simultaneously.Article Outline1. Introduction2. Related research work3. Materials and methods 3.1. Preliminary planning . Analyzing constraints. Genetic algorithm .1. Selection.2. Crossover.3. M

23、utation3.2. Secondary and detailed planning . Coding strategy. Population initialization. Fitness function. Selection operator. Crossover operator. Mutation operator4. Results and discussion5. ConclusionReferencesDesign-to-fabrication automation for the cognitive machine shop自动化加工车间的设备和作业过程协调协同化设计To

24、 meet the rising demands for pure customization of products, new approaches for automated fabrication of customized part geometry are needed, on both the software and hardware side, that balance flexibility, robustness and efficiency. This is a great challenge since today it requires significant hum

25、an expertise supported, only partially, by computer-aided approaches. This paper introduces a new approach and framework for an autonomous design-to-fabrication system that integrates cognitive capabilities, such as reasoning from knowledge models and autonomous planning, and embeds these in the mac

26、hines themselves to automatically fabricate customized parts. The framework integrates into a common process automatic workpiece selection using an ontology, generative CNC machining planning using shape grammars and automated fixture design, based on a novel flexible fixture device hardware. Initia

27、l results are given for the machining planning approach applied to 2.5D parts with a defined approach direction and the prototyped fixture device is presented. The advantages and potential of the framework stem mainly from applying the principles of cognitive technical systems to a fabrication system to develop an integrated and on-line approach. The methods are developed specifically for use on the machine shop floor to take advantage of the possibility to up