【作者】 王文斌；

【导师】 俞涛；

【作者基本信息】 上海大学 ， 机械制造及其自动化， 2007， 博士

【摘要】 可重构制造系统是未来制造系统的发展方向，而实现面向设备级的重构是实现可重构制造系统的基础和关键。只有作为主要制造设备的数控机床具备可重构的特性，才有可能实现制造系统的可重构。数控系统的可重构性已成为衡量现代数控系统性能优劣的重要指标之一。当今随着芯片技术的发展，嵌入式微处理器正成为后PC时代的主流，并向高速、智能化的方向发展，其在功能、结构、接口、通信等方面都具有优越性，这些优越性都很好的满足了现代数控的发展需求。并且90年代末，随着嵌入式Linux、uCOS等开源嵌入式操作系统的出现，更是为嵌入式系统在现代数控上面的应用提供了广阔的天地。但是目前国内外基于嵌入式系统的数控开发刚处于起步阶段，大多是针对具体数控应用需求而定制开发的，而且嵌入式系统存在资源有限性、平台相关性等特点。这使得数控系统开发难度大，周期长，系统的可重构性不高。因此，本文针对嵌入式环境下，数控系统的可重构实现及其关键技术展开研究。论文从方法论的角度分析并研究了嵌入式可重构数控系统的体系结构，研究了可重构数控系统的软件实现问题和嵌入式可重构数控系统实时多任务的调度问题，在此基础上，研制了嵌入式可重构数控系统的集成开发环境原型。最后将研究成果应用于水射流数控系统和全自动线束机数控系统的开发上，通过实际应用验证研究结果的合理性和可行性。具体研究内容如下：1、研究了目前数控系统体系结构，并对可重构数控系统的复杂性进行充分分析，指出了数控系统体系结构对于可重构数控系统的支配作用。通过对方法论的研究，提出了解决数控系统复杂性问题的具体策略。在其指导下，分析了数控系统的构成、信息流、行为、模块连接，提出了基于活动对象的轻量级软件总线的可重构数控系统体系结构。并对基于方法论的系统可重构实现过程进行简要描述。2、分析了现有的构件标准模型，针对嵌入式资源有限、平台差异大、可靠性高等特性，提出了一种嵌入式数控构件模型ECRNC。研究了ECRNC模型主要构成元素，给出其构件规约和实现方式。分析了层次软件总线特点，给出其关键实现技术。3、分析了数控系统的多任务运行的特殊性，结合嵌入式运算资源的有限性，提出一种混合实时任务层次调度算法。在一级调度上用DRM保证实时任务的底限不丢失，在二级调度上采用了动态规划和贪婪相结合的策略调度实时任务的可选部分，保证了带宽的利用，克服了传统混合调度算法处理器利用率受限制、系统开销较大和非周期部分响应时间长的问题。4、分析了现有的构件库的表示方法，建立了面向嵌入式数控构件的刻面表示模型，从而将构件的描述展开为一棵刻面描述树。通过研究刻面描述树，将构件描述和构件检索间的匹配模型转化为树型结构化描述之间的匹配模型，并给出其实现算法。针对检索适配后，多个可行的系统选择方案，提出适应性分析模型，并首次将模糊层次分析法应用于构件系统方案的适应性分析中，并通过实例分析其有效性。由此建立了可重构数控系统集成开发环境原型。5、基于上述工作并为验证之，研制了水射流数控系统和线束机数控系统。更多还原

【Abstract】 The reconfigurable manufacturing system (RMS) is a direction of future manufacturing system. It includes system-level reconfiguration and machine-level reconfiguration. Computerized numerical controlled (CNC) machines are the main parts of manufacturing system. It is possible to realize RMS if a CNC machines has the capability of reconfiguration. This capability has become one of the performance indexes to modem CNC machines.With the development of semiconductors technologies, the embedded micro-processor is becoming the mainstream of the post PC market. It is high-speed, small, powerful, multi functional, and integrates high performance core with a rich set of peripheral functions focused on communication. These advantages greatly satisfy the development of the modem CNC machines. Besides some embedded operating systems, such as embedded Linux, uCOS, based on GNU software,is robust and open sources, provide widely application space for CNC machines controller based on embedded system. As the beginning step based on embedded system at home and abroad, most CNC systems have been developed according to their specific request, together with the resource limit and platform relativity of the embedded system, which make development hard, long time and reconfiguration impossible.This thesis emphasizes on CNC system reconfiguration and its key technology based on embedded system. It analyses the architecture of embedded reconfigurable CNC system from the point of view of the methodology. Then study the software and multi-task schedule algorithm of the reconfigurable CNC system, and a prototype of reconfigurable CNC system IDE (Integrated Development Environment) is built up. In the end the water-jet CNC system and wiring harness CNC system have been developed to verify the research result. The details are organized as follows:The current architecture and complexity of the CNC system have been researched, with the result that the architecture is the fundament of the reconfigurable CNC system. Based on the research of the methodology, the exact polices to solve the complexity of the CNC system have been put forward. With these polices, the thesis analyzes the structure, the communication, the behavior and the connection of the CNC system, and bring forward a light software bus architecture based on activity object. Then a brief description about reconfigurable process has been given.Analyzing current standard component models, and considering the software and hardware characteristic of embedded system, such as limited source, great difference between platforms, high requirement of dependability, ECRNC (Embedded Component for Reconfigurable Numerical Controller) a component model used for embedded reconfigurable numerical controller is proposed in this thesis. The elements of the ECRNC, description of the component and the implement also have been researched. And according the characteristic of the software bus, some key technologies about realization have been given.Analyzing the particularity of multi-task schedule in CNC system, this thesis provides a hierarchical scheduling algorithm of real-time tasks. The algorithm guarantees that the deadlines of real-time tasks will not be missed by using DRM strategy on the first level and makes good use of bandwidth by applying the dynamic programming and greedy strategy to the scheduling of the optional components of real-time tasks on the second level. The algorithm overcomes the difficulties of the traditional hybrid scheduling algorithms such as the restriction of processor utilization, the high system overhead and the long responsive time.Researching the representing methods of software components, the representing method based on facet model for embedded CNC system is suggested. So a method based on tree inclusion is proposed to retrieve reusable components classified in faceted scheme, which combines the theory of tree matching and the feature of faceted classification scheme. And aim at multi schemes from tree matching, an adaptability analyzing model based fuzzy analytic hierarchy process (FAHP) is brought forward to choose optimal adaptability selection. An example is given to demonstrate the feasibility and effectiveness of this model. And a prototype of NC system IDE is built up.Based on the achievements mentioned above, a water-jet CNC system and wiring hamess CNC system with reconfigurable architecture have been developed successfully.更多还原