Zhi Yong Chang

Study on Product Service Oriented Enterprise Servitization Methods

In order to servitize manufacturing enterprises and meet the need of product service system, approaches to servitization are studied. Design for service method, manufacturing for service mode, and product-based service are regarded as key problems and discussed in detail respectively. Concept and evaluation standards of product service relationship are also discussed. And some significant topics for future studies are put forward.

Study on Key Technologies of Aero-Engine AMRO Support System

In order to solve the digitalized management problem of aero-engine in the whole lifecycle, a framework of aero-engine AMRO supporting system is put forward. Management of assembly, maintenance, repair and overhaul are involved. Modeling and integration of aero-engine status data, assembly process management, on-spot operation guide, online education support, integration and synchronization of data and fault diagnosis support are regarded as key enabling technologies and studied deeply. Correspondent solutions are given respectively. The assembly digitalization sub-system and the IETM sub-system are developed to validate the proposed system. And close-loop controlling of single aero-engine information is achieved, and the study provides technology support for improving level of aero-engine status digitalized management.

An interactive 3D Assembly Process Model

To enable interaction between part models in the 3D assembly process and real manufacturing resources, an extended assembly step model is proposed. Information about manufacturing resources is classified as static information, check item and check result, which endows assembly steps with dynamic interaction ability. The automatic match mechanism between virtual models and real manufacturing resources is put forward to make the interactive assembly step model practical. An implementation framework is also discussed to turn the interactive assembly process into reality.

A Fuzzy Set AHP-Based DFM Tool under Concurrent Engineering Environment

In the light of growing global competition, organizations around the world today are constantly under pressure to produce high-quality products at an economical price. The integration of design and manufacturing activities into one common engineering effort has been recognized as a key strategy for survival and growth. Design for manufacturability (DFM) is an approach to design that fosters the simultaneous involvement of product design and process design. The implementation of the DFM approach requires the collaboration of both the design and manufacturing functions within an organization. At present, For some reasons DFM approach is ineffectively including lack of interdisciplinary expertise of designers; inflexibility in organizational structure, which hinders interaction between design and manufacturing functions. Design for manufacture is the practice of designing products with manufacturing in mind. Early consideration of manufacturing issues can shorten product development cycle time, minimi overall development cost and ensure a smooth transition into production. In this paper, part manufacturability under Concurrent Engineering (CE) environment was analyzed in detail. An evaluation system of DFM was proposed according to CE ideas. A fuzzy set-based manufacturability evaluation algorithm is formulated to generate relative manufacturability indices to provide product designers with a better understanding of the relative ease or difficulty of machining the features in their designs. An analytic hierarchy process (AHP) method is introduced to assign weighting factors to features to reflect their functional importance. Results from the case studies show the method available and practicable.

Machining Process Knowledge Discovery Technology: On the Basis of MBD Process Model

To tackle process knowledge discovery difficulty in machining process, this paper studies knowledge discovery method of 2.5–dimensional machining characteristics based on process model with model based definition technology, and finds out machining process design knowledge with the natural structured process description ability of MBD process model. Firstly, the composition of machining geometry ontology and process ontology is analyzed. Secondly, decision tree between ontology are obtained by analyzing abundant samples of MBD process model. Thus, the process and method of reasoning from geometry ontology to process ontology is achieved. Finally, the validity of process knowledge discovery method is exemplified with a group of MBD process models.

Study on Key Techniques of Parametric Design System Based on Solid Works and KBE

This paper analyzes the current status and inadequate of three-dimensional parametric design, and introduces the conceptions and principles of KBE (Knowledge Based Engineering) technology and the parametric design. The key techniques of parametric design system are studied based on the platform of combination of SolidWorks as three-dimensional feature modeling software, Microsoft Access as supported database and Microsoft Visual Basic as the development tool. Firstly, we divide the product into modules by functions. Secondly, invoke corresponding knowledge and methods of design and calculation in the KBE knowledge base to perform design and calculation. Then we use parametric modification method combined with equations, values link and design tables to get the parametric models, judge the rationality of the design parameters through finite element analysis, and create the drawings which meet the processing and production requirements using drawings automatically adjustment technology. Finally a case study of stacker design is given to validate these techniques of parametric design system, and show that the techniques have great significance for improving product design quality, shorting the design cycle and improving the competitiveness of enterprises.

Petri Nets-Based Implement Process Model for Engineering Change on Aero-Engine Assembly Field

The traditional artificial mode of engineering change implementing in aero-engine assembly field often results in difficulties of the process control. To solve this problem, this paper firstly puts forward an aero-engine assembly field configuration relationship model (AACRM) based on the configuration data structure and correlation coordination relationship between configuration items, then analyzes the structure of engineering change document and its implementation process in assembly field. Lastly, assembly field engineering change implementing process model (AEIPM) is established based on Petri nets modeling method, which constructs the implementing and confirming process of engineering change from a product level to a step level and then from a step level to a product level.

The Key Technology Research of Knowledge Modeling Method for Complex Product Design

The purpose of this paper is to build knowledge description model for complex product design. In order to uniform the semantic of glossary in design process, an extensive glossary semantic tree is built up and the corresponding semantic similarity calculation algorithm is proposed. The complex design knowledge can be divided into instance pattern, chart pattern, formula pattern and rule pattern. The knowledge models are proposed for these four pattern knowledge models. At last, a design knowledge modeling and reusing system for complex product is achieved, and the design knowledge can be inherited by it.

Research on the Algorithm of Technological Dimension Chain Based on 3D Process Models

Aiming at the wide application of technological design in three-dimensional CAD software, while the technological dimension chain’s calculation is completed in the two-dimensional process sketch still. A sort of method of calculating technological dimension chain was put forward, which is based on three-dimensional process model. Three-dimensional process model is created through the process of technological design by introducing the concept of three-dimensional process model, and then, the information of process dimension is extracted from the three-dimensional process model and a tree oriented process dimension structure is established. On the basis of the above, we can proceed with technological dimension chain’s integrated calculation and analysis, redistributing the process dimension and its corresponding allowance dimension and tolerance. It will offer more reasonable and reliable process parameters to the technologists in the design of process route, and also effectively solve the problems of the technological dimension chain’s calculation involving to CAPP system in the environment of three-dimensional CAD software.

Research on Machinability and Evaluation Methods of Feature-Based Part under Concurrent Engineering Environment

Part manufacturability under Concurrent Engineering (CE) environment was analyzed in detail. An evaluation system of Design For Manufacturing (DFM) was proposed according to CE ideas. The evaluation methods for part manufacturability feature-based are intended to present in this paper. Product design can be guided according to feedback information by evaluating the part manufacturability. Finally an example of rabbet-feature manufacturability of a turbine blade was given to show the method available and practicable.