Intelligent manufacturing system of impeller for computer numerical control (CNC) programming based on KBE

The objective of all manufacturers is to produce high-quality products at reasonable prices. In high-volume mass production systems, optimizing the operation sequence (OS) not only reduces product cost but also increases production efficiency. An optimal OS can be achieved by trimming unnecessary segments of motion from the tool path (TP), which reduces production time. Currently, a computer numerical control (CNC) program can be generated for a given TP by the number of automatic programing packages (APPs) that are currently available. However, TP optimization is not included in most APPs. In this study, we propose genetic algorithms (GAs) to determine the optimal OS for the TP pass through a set of operations located asymmetrically in multiple levels and using one or more cutting tools. Then, the CNC program of the TP will be generated. The traveling salesman problem is introduced to define the OS problem. A GA based on the TSP formulation can determine the OS that achieves the shortest TP. The incorporation of a GA and TSP can be integrated into the APP for TP optimization before creating CNC programs.

<div class="htmlview paragraph">The introduction of a Computer Numerical Control (CNC) wing fastening facility in BAE SYSTEMS Airbus UK for the Airbus A340-600 wing led to substantial efforts to reduce Numerical Control (NC) programming time. Since specific values had to be determined for each of 110,000 fastener locations, manual calculations and input had to be eliminated. The decision was made to generate an intelligent CAD model, with “attributes” attached to each fastener location. These attributes would hold three-dimensional information regarding the cross-sectional dimensions of the assembled components at each fastener location, calculated using Knowledge Based Engineering (KBE) software, prior to the NC programming process. The NC software was then configured to read this as background data to programming instructions and to generate output accordingly. This process reduced data preparation by 90% giving significant savings in NC programming time compared to existing methods, with a marked improvement in machine cycle time and quality of first article components.</div> <div class="htmlview paragraph">This paper will explain the development of a knowledge-based NC programming system, and will identify the need for improvement, the existing methods of data preparation, the development of an efficient system and the inherent benefits associated with its implementation.</div>

…On the direct programming of CNC milling equipment

To promote the research and development of modern digital and intelligent manufacturing technology and overcome shortcomings of computerized numerical control(CNC) programming for complex components, an innovative idea has been proposed to introduce knowledge based engineering (KBE) into the field of CNC programming within the integrated environment of CAD/CAPP/ CAM. This paper constructs the architecture of CNC programming based on KBE within CAD/CAPP/CAM and explores the key technology of applying KBE to CNC programming — knowledge representation, knowledge acquisition, knowledge reasoning, and generalized knowledge base system of CNC programming. The integration of the CAD/CAM system and the CAPP system of enterprises has been achieved by taking the powerful CAD/CAM system of UG NX as a platform. The prototype system of CNC programming for complex components based on KBE within CAD/CAPP/CAM has been developed by means of UG/Open,VC ++ 6.0, and SQL Sever 2000. Finally, a frame example, one of the complex components of a marine diesel, is presented, and the academic production and the intelligence of the system are verified.

A programming to make parts are CNC Programming (Computer Numerical Control Programming) for machines. An NC program consists of a sequence of instructions that control the motion and automatic sequences of an NC Machine to perform a particular processing task. In a general sense, the term NC programming refers to the creation of control data for machining workpieces on NC and CNC machines. NC programming has a decisive influence on the cost-effectiveness and profitability of NC manufacturing. The selection of a programming system is mostly guided by the need for software that is suitable for the application at hand, readily available, and as universally applicable as possible.

For the deployment of both Product Lifecycle Management (PLM) and Knowledge-Based Engineering (KBE) approaches, product and process engineering knowledge needs to be identified, acquired, formalized, processed and reused. While knowledge acquisition is still a bottleneck process, the formalized engineering knowledge is still too often encapsulated in CAD models and in KBE systems developed in vendor-specific environments. To address this issue, this paper introduces a possible solution enabling the enrichment of a CAD-KBE-PLM integration schema that provides a standardized and neutral representation of engineering knowledge for further reuse across heterogeneous CAD, KBE and PLM systems. To enrich this schema, the proposed solution combines the use of a Multi-CAD API library – which allows platform-independent and automatic extraction of engineering knowledge from CAD models into an XML-based representation – and a Knowledge Acquisition and Formalization Assistant (KAFA) which assist domain experts to formalize their procedural knowledge.

This study was an attempt to control and monitor Computerized Numerical Controller (CNC) machines anywhere and anytime for the development of a ubiquitous machine (u-machine). With a Personal Digital Assistant (PDA) phone, the machine status and machining data of CNC machines can be monitored in wired and wireless environments, including the environments of IMT2000 and Wireless LAN. Moreover, CNC machines can be controlled anywhere and anytime. The concept of the anywhere-anytime controlling and monitoring of a manufacturing system was implemented in this study for the purpose of u-manufacturing and u-machines. In this concept, the communication between the CNC controller and the PDA phone was successfully performed anywhere and anytime for the real-time monitoring and control of CNC machines. In addition, the interface between the CNC controller and the developed application module was implemented by Object linking and embedding for Process Control (OPC) and shared CNC memory. For communication, the design of a server contents module within the target CNC was based on a TCP/IP. Furthermore, the client contents module within the PDA phone was designed with the aid of embedded c++ programming for mobile communication. For the interface, the monitoring data, such as the machine status, the machine running state, the name of the Numerical Control (NC) program, the alarm and the position of the stage axes, were acquired in real time from real machines with the aid of the OPC method and by sharing the CNC memory. The control data, such as the start, hold, emergency stop, reserved start and reserved stop, were also applied to the CNC domain of the real machine. CNC machines can therefore be controlled and monitored in real time, anywhere and anytime. Moreover, prompt notification from CNC machines to mobile phones, including cellular phones and PDA phones, can be automatically realized in emergencies.

A computerised minimum distance algorithm for machining of sculptured surfaces

The irrigation decision-making system based on knowledge-based engineering (KBE) is reported in this paper, and the basis of the KBE was knowledge of reference crop evapotranspiration (ET0). Therefore, the research examined the accuracy of the support vector machines (SVMs) in the model of ET0. In the first part of the study, the SVMs were compared with FAO-24, Hargreaves, McCloud, Priestley-Taylor and Makkink models. The results indicated that the SVMs performed better than other models. In the second part, the total ET0 estimation of the SVMs was compared with the other models in the validation. It was found that the SVMs models were superior to the others in terms of relative error. The further assessment of SVMs was conducted, and confirmed that the models could provide a powerful tool in KBE irrigation with a lack of meteorological data. It could provide a reference for accurate ET0 estimation in KBE irrigation systems.

ABSTRACT:The diverse knowledge levels among first-year mechanical engineering students lead to significant disparities in individual learning. Intelligent tutoring systems (ITS) offer a solution by providing tailored digital one-to-one instruction, bridging knowledge gaps, and equalizing learning outcomes. This thesis develops an ITS for design theory based on a knowledge-based engineering system, presenting an innovative model that integrates key features of ITS and knowledge-based systems. Implemented in a specialized environment, the system’s application and validation demonstrate its ability to meet context-sensitive design teaching requirements and provide adaptive tutoring.

This paper reports on a system that has been developed to facilitate the structure and reuse of engineering rules (ERs) in Knowledge-Based Engineering (KBE) systems. The proposed structure for rule elements supports the traceability of knowledge sources as well as where the knowledge elements are used in KBE applications. This forms the infrastructure to systematically manage the use and reuse of knowledge and control the version and update of the rules when new knowledge is gained. Representing product knowledge in rules is a way to capture the know-why of the design by modelling the decisions involved in the design process. KBE has been used as the mechanism to deploy this knowledge. Although the KBE technology can support the management of this knowledge, the maintenance of the knowledge is often a neglected task. This leads to a number of practical difficulties in the large scale rollout of KBE applications. To design an improved KBE rules maintenance system, the research team developed a generic representation to unify the off-line storage of the IF, COND and CASE statements used in the ICAD Design Language. Additional data fields are defined to maintain the traceability of the origin and use of rules. This is implemented in a Microsoft Access database. The integration of this off-line rule repository with the ICAD KBE system is achieved and validated in an industrial application. The data structure defined and the implementation system is detailed in this paper.

The re-use of product knowledge is vital to the development of Knowledge-Based Engineering (KBE) systems and to the deployment of Product Lifecycle Management (PLM) strategies. This paper addresses the challenges related to KBE-PLM systems integration in order to unlock engineering knowledge from proprietary representations and to manage the lifecycle of KBE models as well as their usage by different design automation applications. Essential constituents of product knowledge are identified and analyzed and the concepts of design intent and design rationale are re-introduced as key enablers to re-use this product knowledge in the appropriate KBE context. The paper introduces a KBE-PLM integration framework including a platform-independent Open KBE repository structured according to the KBE-PLM integration schema. This schema is a multi-layer neutral product and knowledge data model designed for integrating information from parameterized Computer-Aided Design (CAD) models, rule-based KBE systems and PLM systems.

Integrating knowledge-based systems and databases

In recent years, the productivity of machine tools have been significantly improved by using computer based CAD/CAM systems for Computer Numerical Control(CNC) program generation. There are many CAM software in the market that provide tool path programming and can be applied to different types of machining. However, in most cases the efficiency of machining in CNC is still relied on the optimization of the tool path. Hence, this present paper presents a Genetic Algorithm Tool Path Optimization (GATPO) method using to obtain the shortest tool path for three axes CNC drilling machine. A user friendly Graphical User Interface (GUI) has been developed using MATLAB to input various parameters which adapts Travelling Salesman Problem(TSP) in determining the distance took during machining. Two kinds of crossover method have been applied, i.e., single-point crossover and two-point crossover to observe the effect of them. The simulation result ascertained that our proposed GA based tool path optimization is useful to find a lower distance of tool path generation for hole drilling process.

Today’s textile-apparel industrial complex is characterized by a multitude of conflicting demands: smaller lot sizes, increased product flexibility, higher product quality and decreasing delivery times. The textile/apparel industry must deploy state-of-the-art manufacturing and information management techniques to operate successfully in such a demanding and highly competitive global market. In this context, the role and scope of mechatronics in textile-apparel production systems are discussed with specific examples. The need for techniques and tools such as information engineering, electronic data interchange and knowledge-based systems technology is established and their relevance to the textile-apparel complex is discussed. An overview of major research endeavors including the development of an enterprise architecture, knowledge-based systems and product data standards is presented. Finally, some topics for further research in areas ranging from distributed design and manufacturing to the development of product data exchange standards are proposed.