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81.
CAM(内容可寻址存储器)是一种快速匹配存储器件,在通信、雷达等许多领域有着广泛的应用。在介绍CAM基本原理的基础上,例举了一种基于CAM实现关联比较器的设计方法,通过仿真验证了设计的正确性,基本上实现了雷达信号的纯硬件快速预分选,达到了实时性和可靠性要求。  相似文献   
82.
描述了以CAD/CAM软件Pro/E及注塑模分析软件为平台,采用系统集成的方式,并运用Pro/E的二次开发工具Pro/TOOLKIT,按并行工程思想,对注塑模CAD/CAM/CAE系统的设计和开发进行的分析和研究.  相似文献   
83.
Though there are already a variety of models for complex surfaces, they are not so convenient as needed in practice. A hierarchical model and the principle of decomposition and reconstitution for complex surfaces have been proposed, which have the potential to enhance the support of automated design systems on creative work intelligently Then the progress made is discussed involving the applications of the new principle in the following three areas:conjugation surface calculation, tool path generation in numerically controlled machining, and machining process innovation by re-recognition  相似文献   
84.
以OOEDB为核心的集成化CAD/CAPP/CAM 系统GS-ICCC的设计与实现   总被引:7,自引:0,他引:7  
GS-ICCC是一个以自行研制开发的面向对象工程数据库管理系统OSCAR为核心的集成化CAD/CAPP/CAM系统,它的主要特点是按照STEP标准在全局产品数据模型基础上实现CAD,CAPP,CAM的信息集成,本文围绕着这一原则介绍了GS-ICCC的系统总体结构,OSCAR功能组织,全局产品数据建模框架以系统集成的设计与实现。  相似文献   
85.
PDE造型方法在复杂曲面设计中的应用   总被引:4,自引:0,他引:4  
马岭  朱心雄 《计算机学报》1998,21(Z1):357-362
研究了偏微分方程曲面造型方法在飞机外形设计中的应用.该飞机模型的机翼具有边条,因而给曲面造型带来一定的困难.本文应用周期PDE曲面片,构造出了机身与机翼之间G1光滑拼接的过渡面.同时,用PDE方法构造出机身与前小翼及尾翼间的过渡面.实践表明,PDE方法在光滑拼接过渡面的设计中简便实用.  相似文献   
86.
This paper presents the development of a collaborative CAD/CAM system (COCADCAM). COCADCAM extends an existing single-location CAD/CAM system to a multi-location CAD/CAM application so that two geographically dispersed CAD/CAM users can work together on a three-dimensional CAD-geometry coediting and CAD-related tasks collaboratively and dynamically. COCADCAM dynamically supports CAD data communication that are not available in traditional single-location CAD/CAM. The dynamic data communication is achieved through the development of networking algorithms and CAD/CAM functions in this paper. The networking algorithms based on UNIX Interprocess Communication (IPC), the Network File System (NFS), and a connection-oriented client and server model under the Transmission Control Protocol/Internet Protocol (TCP/IP) suite. The CAD/CAM functions included surface modelling, simulation of a milling toolpath, and post-processing of an NC program following collaborative CAD-geometry coediting, which are directly or indirectly supported by the Application Programming Interface (API) of the CAD/CAM software. The networking algorithms and CAD/CAM functions together can facilitate an environment for CAD-geometry coediting and related tasks such as design, analysis and manufacture. COCADCAM has been successfully implemented through local area network (LAN) and the Internet; a remote machining cell is also linked so that the generated NC program based on a coedited free-form surface can be used for the physical machining operation. The algorithm proposed by COCADCAM can be referenced for the extension of other single-location CAD/CAM systems to multi-location applications.  相似文献   
87.
型腔高速铣削刀轨生成算法研究   总被引:3,自引:2,他引:3  
在常规的环切刀轨生成算法基础上,设计了型腔高速铣削加工刀轨生成算法.对刀轨的拐角进行了平滑处理,实现了相邻刀轨环之间的光滑曲线过渡,避免了刀具运动方向的急剧变化,可使切削性能得到改善.  相似文献   
88.
Design formalism for collaborative assembly design   总被引:1,自引:0,他引:1  
Joints in product design are common because of the limitations of component geometric configurations and material properties, and the requirements of inspection, accessibility, repair, and portability. Collaborative product design is emerging as a viable alternative to the traditional design process. The collaborative assembly design (AsD) methodologies are needed for distributed product development. Existing AsD methodologies have limitations in capturing the non-geometric aspects of designer's intent on joining and are not efficient for a collaborative design environment. This paper introduces an AsD formalism and associated AsD tools to capture joining relations and spatial relationship implications. This AsD formalism allows the joining relations to be modeled symbolically for computer interpretation, and the model can be used for inferring mathematical and physical implications. An AsD model generated from the AsD formalism is used to exchange AsD information transparently in a collaborative AsD environment. An assembly relation model and a generic assembly relationship diagram are to capture assembly and joining information concisely and persistently. As a demonstration, the developed AsD formalism and AsD tools are applied on a connector assembly with arc weld and rivet joints.  相似文献   
89.
针对传统泣塑模CAD系统的缺陷,提出并分析了新型注塑模系统的总体设计方案和3DMCAD/CAM系统构建语言,由此实现了柔性化注塑模CAD系统,包括模架、抽芯机构、浇口套等机构及其孔型的信息获取、自动生成、更新和删除。  相似文献   
90.
Once a machining process is finished, an inspection process is carried out to check whether the part is within dimensional tolerances. A coordinate measuring machine (CMM) is a general metrological device for assessment of dimensions on the shop floor. It cannot be ignored, however, that CMM measurements require significant resources in operating time and cost, which has led to many studies into on-machine measurement (OMM) systems. This study aims to develop an OMM system with a noncontacting laser displacement sensing apparatus and a computer-aided design (CAD) model for ease of operation, improved operating speed, and free form profiling. The system is composed of two software modules, one for sensor alignment with the machine tool and the other for measurement based on CAD/CAM (computer-aided machining). Consequently, the system was verified on the shop floor at a numerical control (NC) machining center.  相似文献   
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