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941.
A geometrical approach to computer-aided process planning for computer-controlled machine tools 总被引:6,自引:0,他引:6
A. M. Luscombe D. J. Toncich 《The International Journal of Advanced Manufacturing Technology》1996,11(2):83-90
This paper documents part of a research program which has been under way at the CIM Centre at Swinburne University of Technology since 1989. The purpose of the research program was to develop an open-architecture machine tool control system and then to see how that system could be used to change the distribution of traditional manufacturing design, planning and control functions. This paper examines one part of that research program and focuses on a methodology which could prove to be useful in the machine tool selection, cutter selection and cutter path generation phases of process planning for cutting operations on workpieces in computer-controlled machine tools.It is suggested that a configuration space transform be used for each cutter/machine tool combination to find the volume that the combination could remove from the uncut workpiece without removing any of the material that will form the final workpiece. A method of comparing these volumes from different combinations is then outlined. The output of this method is a reasonable sequence of machine tools and cutters. Path planning can then be carried out for each of the chosen combinations using a method similar to the one used to find the possible volume to be removed.Possible implementation techniques, and their limitations on existing computer hardware, are discussed and the most promising of these are identified, based upon some properties of configuration space transforms. 相似文献
942.
Hilmi N. Kamhawi Steven R. Leclair C. L. Philip Chen 《Journal of Intelligent Manufacturing》1996,7(1):55-67
This paper addresses the feature sequencing problem in the Rapid Design System (RDS). The RDS is a feature-based design system that integrates product design and process planning. An important issue in feature-based process planning for machined parts is the order in which material is removed to form the resultant part. The order, or sequence, is partially dependent on the geometric relationships between features. The sequence affects the safety, the time it takes to machine the part, and the quality of the finished part. The sequence of material removal depends on two types of relations between features: (1) intersections and (2) interfeature associations. Both types of relations compound the search for an optimal sequence of material removal. Therefore, the research problem has been the discovery and development of a genetic algorithm (GA) that efficiently searches the solution space for all possible sequences and identifies the best sequences in terms of safety, time and quality. 相似文献
943.
Reasoning about change is a central issue in research on human and robot planning. We study an approach to reasoning about action and change in a dynamic logic setting and provide a solution to problems which are related to the Frame problem. Unlike most work on the frame problem the logic described in this paper is monotonic. It (implicitly) allows for the occurrence of actions of multiple agents by introducing non-stationary notions of waiting and test. The need to state a large number of frame axioms is alleviated by introducing a concept of chronological preservation to dynamic logic. As a side effect, this concept permits the encoding of temporal properties in a natural way. We compare the relative merits of our approach and non-monotonic approaches as regards different aspects of the frame problem. Technically, we show that the resulting extended systems of propositional dynamic logic preserve (weak) completeness, finite model property and decidability. 相似文献
944.
945.
大型煤炭建工集团管理信息系统 总被引:3,自引:2,他引:1
介绍了中平能化建工集团管理信息系统的总体设计方案、网络及软件平台架构、子系统功能模块组成等。该系统采用智能客户端网络架构和万向接口平台技术,实现了建工企业的全部专用功能以及各个子系统之间的信息交互,使得各机构之间能够有效地协同运作。 相似文献
946.
针对夜间或恶劣环境下交通事故频发的情况,提出一种在夜间或恶劣环境中辅助驾驶员改善能见度的技术,本技术是采用在FPGA内部对CCD捕获的可见光视频流和红外摄像机捕获的红外视频流进行实时融合、处理以获得极低或极强光照条件下图像信息的新方法;整个系统流程都在FPGA内实时完成,经过处理的视频流直接显示在位于司机前方的平视显示器上,以协助驾驶者在能见度低的环境中安全地行驶,在各种实验条件下经初步验证都取得了不错的效果。 相似文献
947.
948.
949.
针对蓄热式加热炉具有多变量、时变、非线性、耦合、大惯性和纯滞后等特点,当前时于蓄热式加热炉的空燃比控制主要还是人工操作完成的问题,通过对蓄热式加热炉空燃比变化这一复杂的工业过程的分析,提出了一种蓄热式加热炉空燃比控制方法,设计了一个基于智能的空燃比控制系统.用无辨识自适应方法预测热值,用模糊神经网络预测烟气残氧量,解决... 相似文献
950.