Research on Open CNC System Based on Software Component Technology

The openness and reliability of CNC system is the focus and hotspot of current computer numerical control system (CNC) research. The measures to solve the open problem mainly focus on the open research of the architecture and the reliability issues include hardware reliability and software reliability. The research ideas are more limited in improving the reliability of hardware. However, as the software part of the core of the system, its reliability is also worthy of attention. In today's rapid development of microelectronics technology, large-scale ultra-large-scale integrated circuits and large-scale production, hardware reliability has been better solved, software reliability. In fact, in the field of software engineering research, software reuse technology (also known as software reuse technology) has emerged. In addition to improving system reliability, the technology improves production efficiency, reduces duplication of work, and reduces energy consumption. Aspects are also very important. It can be divided into two ways: product reuse and process reuse. Component-based reuse is the main form of product reuse, and it is also the focus of current reuse research. At the same time, in the field of distributed object research, software component technology is also an important content. Current software component technology is regarded as one of the key factors to achieve successful reuse. The wide application of software reuse technology will promote the transformation of the software industry. Its heavy component work, software component production will become an independent industry, and the application of software reuse technology to numerical control systems is relatively rare. There are only a few units, such as Huazhong University of Science and Technology, Zhejiang University, etc.>4 Zhejiang University put forward the idea of ​​reconfigurable virtual CNC system based on software component technology, and developed the system prototype Huazhong University of Science and Technology proposed Reuse of the development idea of ​​CNC software chip, and successfully developed a software chip development thinking fund project: Zhejiang Natural Science Fund Project (599026); Zhejiang Science and Technology Plan Key Project (001101061-for, "with standardized interface The basic class is called a software chip."

The object-oriented CNC software modular description and implementation are divided into three levels: system, control unit and basic class. This development idea makes full use of some features of object-oriented language, such as easy representation of object-oriented design, inheritable and derivable. Etc., in order to meet the requirements of software reuse, and make the CNC chip easy to expand and modify, therefore, the software has a certain degree of openness.

The development method based on component technology is revolutionizing the traditional software development method. By using the software components of the product to integrate the system software, the advantages of the object-oriented language can be well utilized, and the object-oriented language can be compensated. Some of the less than 1 component technology and the open CNC system 11 component of the conceptual component is a self-contained software module that can provide a certain function, it encapsulates certain data and methods, and provides specific interface developers can use a specific interface to use Components and communicate with other components to construct an application component to compare with a class. One significant difference is that the component encapsulates the relevant class, and the class encapsulates the relevant data and implementation functions.

The characteristics of 12 components have strong encapsulation components can be refined into many sub-functions, each sub-function corresponds to an object, the object is composed of data description and function realization, the component only provides a series of interfaces, the user only needs You can understand the overall function of the component and its interface usage, without having to understand the detailed encapsulation inside the component.

Component independent of programming language component development can use visual programming language, such as Visual C++, VisualBasic + BuilderDelphi and so on. The language used by the component integration system used by the user can be different from the language used by the component development. Because the component development and use can follow the same interface protocol, the different languages ​​can work together. The component can be run across the network. The component can be deployed in different languages. On a computer, communication is implemented through some kind of network protocol, so that the distributed application component based on the network environment can be easily upgraded. As long as the external interface of the component is unchanged, the developer can separately upgrade the component function without affecting other components and the entire application. Running. Users can also upgrade the functionality of the component through inheritance and derivation, so that the component has a strong openness. It can fully utilize the function of the object-oriented language to support the implementation of the internal component. It can fully utilize the data abstraction and function of the object-oriented language. Abstract inherits the characteristics of derived polymorphism, which makes the development of the component itself very reusable.

1.3 The concept of open CNC system IEEE defines open system as being able to run on multiple platforms, interoperating with other systems, and providing users with a unified style of interaction. According to this definition, open The CNC system should have the following basic characteristics: Interoperability By providing standardized interfaces, communication and interaction mechanisms, different functional modules can run on the system platform with standard application interfaces, and achieve equal interoperability and coordination. The functional software of the portability system has nothing to do with the device, that is, the application of a unified data format, interaction model, and control mechanism, so that the functional modules constituting the system can be derived from different developers, and the functional modules are made through a consistent device interface. It can run on the hardware platform provided by different vendors. The function scale of the CNC system can be flexibly set and can be easily modified. It can increase the hardware or software to form a more powerful system, and can also reduce its function to adapt to the low end. application.

Complementarity means that the selection of hardware modules and functional software constituting the system is not controlled by a single supplier, and can be replaced according to their functional reliability and performance requirements without affecting the overall coordinated operation of the system.

Comparing the above characteristics with the characteristics of component technology, we can find that there are many similarities between the two. 2 CNC system development based on software components 2.1 Definition of numerical control software components Based on component technology, numerical control software components refer to the ability to complete a certain module of the numerical control system. The function of ActiveX is that it provides the object with the COM protocol, the external has a unified, open interface, and the internal package encapsulates the details of the function implementation. Through ActiveX technology, the programmer or user can assemble these reusable software components into the application or In the service program.

The description of the NC software component can clearly understand the concept and function of the numerical control software component. The numerical control software component can be understood as a powerful component (similar to the hardware component) after integration of multiple software chips, and only has a single function. Compared with the chip, the function is more diversified and more powerful, but like the hardware chip, it also has the basic interface of the address pin input interface, information feedback state setting and control, state acquisition and trigger switch, and its internal It encapsulates the specific details, which is a black box for the user, and the user only needs to use it through the interface. The address pin corresponds to the unique identifier of the software component in the computer, and the input element out interface corresponds to the input method function. If you set the return value of the input method function to an integer, or Boolean variable, you can use it as an input method function. The information feedback black box encapsulates some abstract classes that describe the object. Each class has a set of related abstract data and problems. Implementation composition, different classes can communicate, so that a complex module function can be completed. Users can obtain the functions provided by software components through interface method attribute functions and messages, and can run across networks without being restricted by a certain development language. Very good portability.

In order to standardize the development of numerical control software components, combined with Microsoft's MIDL language and BNF Bacchus paradigm, the numerical control software components can be described as follows: 别〉, <relationship>, <function description>, (storage path), <development situation>, Component Interface>, <Internal Encapsulation>, <Operating Environment>, (Related Algorithm), (Extensible Information)); (Description Document)); <Development Situation>:=((Development Unit), (developer), ( Development tools), (version number), (development time)); <attribute>, <message>); these descriptions can be divided into main information description and auxiliary information description in which the component name, relevance, function description and interface are the main information Description, and the rest is auxiliary information description 2.3 Numerical control software component reusability analysis Based on the above-mentioned standardized numerical control software component description, a reusability analysis can be performed on a component stored in the numerical control software component library. The specific method is to establish a database table according to the description, after each CNC software component is successfully developed, fill out the table, and register the information of the table (which can be constructed according to keywords, multi-faceted classification, hypertext organization, etc.) to the numerical control component library. In the management system. When you need to use it later, you can rely on the complete search function of the software library management system (such as keyword retrieval multi-faceted search, hypertext search, etc.) to access the components of the inventory by finding the main description information to obtain relevant matching or similar statistical results, if statistics The results show that if the matching or function is similar, the other auxiliary description information can be further searched, and the relevant matching or similar statistical results can be combined with the statistical results to determine the reusability of the component.

2.4 The development principle of numerical control software components realizes polymorphism through multiple interfaces, providing incremental or progressive development methods, and it is not necessary to recompile all components in the system when changes occur. The function of interface defined by closely related functions can only realize the functions required by the components. When necessary, the new version of other functional components can be extended through additional interfaces. When adding new interfaces or enhancing interfaces, you can continue to provide originals. Some interfaces simplify the problem of maintaining compatibility. If necessary, subsequent versions of the client application can be used to integrate a more powerful component through multiple components, but to ensure performance stability, operational security reusability, and To reduce the complexity of individual component testing, you should reduce the interdependency between components. Interface definitions should be standardized, unified, and simple. Reduce the number of interface functions and the number of parameters passed.

Internal packaging should take advantage of the object-oriented language, code reuse for the verified basic classes, speed up the basic class requirements of the internal process of the development process, complete functionality and independence. In order to facilitate debugging, the best package for internal packaging After passing the test, it is added to the component; in order to ensure the reliability of the component running in different language environments, it should be tested in different language environments. 25 Software-based CNC system development process based on component technology Development of CNC system using component technology When the software is divided into three levels: system, software components, and glue code. The system is a numerical control application software component that meets the requirements of CNC machining of a certain type of machine tool. As defined above, it has many basic classes. Each basic class completes a certain function glue code, that is, a program or module that connects multiple numerical control components. Even a few lines of code, and the programming language can be any one that supports the COM protocol. According to the characteristics of the component technology and the division of the above software hierarchy, the development process of the software CNC system (see) can be applied to the user's needs, and the numerical control system is proposed based on the general requirements of the numerical control system and other technical requirements or limitations. The solution is based on the system analysis, determine the functional modules, analyze the versatility of these modules and the specificity of the specific CNC system requirements, and then determine which CNC components are needed, and list the components in parallel, the list should reflect Correlation data flow direction between each component, message loop real-time, synergy and other mesh connections.

Access the CNC software component library to find out if there are similar components. If there is a similar component inventory, analyze it by the above reusability analysis method. Components that can be completely reused can no longer be developed, while components with poor reusability can be considered for re-development. Most components have strong reusability and require only an upgrade or a minor modification.

Development or modification of the piece. For the development of a new CNC software component, see the modification of the component, according to the results of the general analysis, the corresponding operation list, the required components are seamlessly integrated by some “glue code”, and assembled into a complete CNC system. However, this kind of connection cannot be accomplished overnight. The safer integration method is partial assembly first, then system integration (5) after system integration, trial operation, and the running feedback results are compared with technical requirements, and the system evaluation is not achieved. If the request is scheduled, the system analysis step is returned to analyze the inadequacies and be modified until the technical requirements are met. From the user's point of view, the construction process of the numerical control system is quite different from the past. In the past, the whole CNC system could only be purchased from the CNC system developer. Due to the limitation of the hardware and software of the CNC system, the upgrade of the CNC system is difficult, and the integration with other CADCAM software also has problems. Now, users can integrate the requirements that meet their own requirements. CNC system / get the compiled result information output method function, although the interface is unified, standardized, convenient to connect with the connected components, first set their own technical requirements, and then perform system analysis, list the required numerical control software components, and Communicate with the component developer, the demand information can be fed back to the developer, help the developer to develop the CNC software components that meet the market requirements, and the user knows that those CNC software components can be purchased. If the user wants to develop some components independently, they can follow the same development process as the opener. Then, the user can assemble the self-developed and purchased components by similar assembly methods, and perform other operations such as system evaluation (see). From the above process, I can develop I~丨 system evaluation, purchase CNC component developers, and develop software-based CNC system processes. The software-based CNC system based on component technology has good openness.

The development of numerical control compiler component is a case of input method function output method function/magnification scale coefficient BooleanmLineTail; / code end mode internal package / store all lines of NC code GValue; / store all lines of G code / store compilation result information CStringArraymMValue; / / Store all lines of M code / proud control program code line number BOOLmCompileSuccess; / as long as there is an error for / / each line of the above-mentioned NC compiler component design, debugging is completed, according to the description of the numerical control software components, Describe and add relevant information to the NC software component library for access and reusability analysis. 786. Dynamic optimization control of redundant robot based on neural network. Ma Guang Cai Hejun Article ID: 1004-13X (2001) 07-0787-03 Neural network-based redundant robot dynamic optimization control Ma Guang Cai Hejun has certain limitations, and the global optimization method is adopted in the research. Based on the idea of ​​global optimization, a dynamic optimization control algorithm for redundant robots is proposed. Due to the difficulty of the numerical calculation of the control algorithm, the neural network is applied in the algorithm, which is used to approximate the complex nonlinear function, so that the problem solving can be simplified. The simulation algorithm can obtain good dynamic performance and operation speed. Fast, motion control of feasible i-redundant robots with engineering applications has always been a hot topic of research. For robot control systems, the optimal control problem is mostly optimized for optimal path planning problem (OPPP) redundant robots. There are two kinds of local optimization and global optimization. From the perspective of complete trajectory tracking, the local optimization scheme is not necessarily optimal globally, and some cause a series of serious problems and even lead to subsequent optimization failure. Therefore, the global optimization is studied. It is of great significance, especially in the case of repetitive work. In the global optimization method, most of the control equations based on joint angle and joint angular velocity are state variables, and the optimal control sequence is used to make the integral performance index reach the extreme value. Since the state and co-state vectors are a pair of twins in the optimal solution

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Conveyor Components are essential spare parts of conveyor system. There are many  types of conveyors are available, such as screw, chain and pneumatic. The most commonly used is the belt conveyor. Belt conveyors are the backbone of bulk material handling systems in many different processing plants. These systems use carts or trains to carry heavy materials like rocks or metal. Such as bulk material handling conveyor or bulk conveyor.  The main function of a bulk conveyor system is to continuously transport and supply bulk materials to units in processing plants. Secondary functions include storage and blending.