A major technological impediment to increasing productivity in the manufacturing sector is the relative absence of automation at most stages of the product design process. One such stage involves the translation of no...
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The difficulties in devising reliable assembly strategies result from tlie complexity and the uncertainties of the assembly process and its environments such as imperfect knowledge of the parts being assembled as well...
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advanced genetic algorithms (GAs) are used to automatically carry out the fine-tuning of the parameter settings of classical PID (proportional plus integral plus derivative) controllers. The basic concept and working ...
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advanced genetic algorithms (GAs) are used to automatically carry out the fine-tuning of the parameter settings of classical PID (proportional plus integral plus derivative) controllers. The basic concept and working principle of GAs are introduced and compared with those of traditional optimization techniques. An advanced GA which can rapidly optimize the parameter auto-tuning process of classical PID controllers is designed based on the GA theory, the authors' experience, and different performance indices, including nonlinear or multiple criteria. The computer implementation of this GA has been accomplished and tested against some benchmark examples. Simulation results demonstrate the efficiency and effectiveness of the proposed tuning technique.< >
The design of a performance constrained stable system is discussed in this paper. The analysis of performance constrained stabilization (PCS) problem is presented with the results obtained through Lyapunov direct meth...
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The design of a performance constrained stable system is discussed in this paper. The analysis of performance constrained stabilization (PCS) problem is presented with the results obtained through Lyapunov direct method. The performance measurement of the process is incorporated with the stability of the system in order to guide the design of the systems under the perturbations and disturbance.
An optical in situ method for simultaneous film thickness and temperature measurements is discussed. Multiple-wavelength pyrometric interferometry (MWPI) is capable of high resolution (0.5 nm for thickness and 0.05 K ...
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An optical in situ method for simultaneous film thickness and temperature measurements is discussed. Multiple-wavelength pyrometric interferometry (MWPI) is capable of high resolution (0.5 nm for thickness and 0.05 K for temperature) and real-time data evaluation. It can be used for processcontrol as well as in situ quality inspection without time delay or additional handling mechanisms and is suitable for monitoring single films as well as multilayer structures. MWPI is insensitive to vibration, rotation and misalignment of the wafer. Due to its optical basis it is also insensitive to hostile environments like high temperature and/or chemically reactive gases. The physical basis of MWPI is outlined as well as the necessary steps of the evaluation procedure. Simultaneous film thickness and temperature measurement during the thermal oxidation of Si is presented. The potential technical impact of MWPI on automation, reliability and long-term performance of semiconductor manufacturing is discussed.< >
The authors propose a synthesis methodology for high-performance pipelined instruction set processors. Designing instruction set processors and constructing their compilers are mutually dependent tasks. Piper is a hig...
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The authors propose a synthesis methodology for high-performance pipelined instruction set processors. Designing instruction set processors and constructing their compilers are mutually dependent tasks. Piper is a high level synthesis tool of the advanced Design automation System (ADAS) which controls the hardware-software interactions at the micro-architecture level. The key function of Piper is to perform pipeline scheduling with any fixed instruction-latency, and generate a reorder table for a back-end compiler to resolve potential pipeline hazards existing in the design. Models for performance and cost of both hardware and software are developed to characterize the design space. A synthesis example of a simple instruction set processor illustrates Piper's synthesis capabilities and how the performance and cost of hardware and software are estimated.< >
The software industry is painfully realizing that a software reuse effort, if not carefully planned and properly carried out, oftentimes becomes an inhibitor rather than a catalyst to software productivity and quality...
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The software industry is painfully realizing that a software reuse effort, if not carefully planned and properly carried out, oftentimes becomes an inhibitor rather than a catalyst to software productivity and quality. Despite numerous ar ticles in the areas of domain analysis, component classification, automated component storage/retrieval tools, reuse metrics, etc., only a handful have managed to address the economics of software reuse. In order to be successful, not only must a reuse program be technically sound, it must also be economically worthwhile. After all, reducing costs and increasing quality were the two main factors that drove software reuse into the software mainstream. This paper presents a number of reuse economics models used to perform an economic assessment of a reuse effort on a large-scale Ada project: the United States Federal Aviation Administration's advancedautomation System (FAA/AAS). Reuse economics models, cost/benefit tracking methods, and reuse catalystslinhibitors are addressed.
F/sub A/TE, an online task-level planning system for an advanced assembly robot consisting of two manipulators and a set of different sensors such as an overhead camera and force-torque sensors, is presented. The plan...
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F/sub A/TE, an online task-level planning system for an advanced assembly robot consisting of two manipulators and a set of different sensors such as an overhead camera and force-torque sensors, is presented. The planning system takes an implicit description of the assembly task, plans a sequence of explicit robot commands and monitors the execution by the real-time robot control system. Because it runs completely online, the planning process is highly reactive using sensor information about the robot's present environment. This planning integrates as a key feature a dynamic mapping of assembly subtasks ready for execution onto the manipulators available at the moment. The system was implemented in Prolog on a SUN 4/75 SPARCstation running Unix.< >
As we move to the point where established techniques are incapable of squeezing out the last few percent of the potential efficiency that needs to be achieved, processautomation has to look towards a new range of con...
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As we move to the point where established techniques are incapable of squeezing out the last few percent of the potential efficiency that needs to be achieved, processautomation has to look towards a new range of control philosophies. Plants are necessarily becoming more and more complex, and that the handling of this complexity presents major challenges. Expert systems are among the few tools coming out of the AI world which offer potential for incorporation into control systems and for supporting the overall structure of supervisory control systems. The technology is at an early stage, and we are really only just beginning to understand its consequences. We must not be intimidated by the technology, but should simply regard it as just another way of programming our computers! This paper addresses the question of using the technology in hard real-time situations. To provide a background to this, an introduction is given to the 'real' requirements of real-time systems. These requirements are matched to expert systems in particular, and some pointers are given as to how current systems are being modified. However, radically new architectures are, of necessity, having to be developed.< >
Summary form only given. The authors point out that a tracked robot (intrabay) system that uses adaptive hardware to reliably load conventional shovel-type cantilevers as well as the Atmoscan-type has been implemented...
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Summary form only given. The authors point out that a tracked robot (intrabay) system that uses adaptive hardware to reliably load conventional shovel-type cantilevers as well as the Atmoscan-type has been implemented into production. In addition, a networked VAX software package has been deployed that controls and gathers data from the furnace controller via its SECS-II interface, making the operation of the furnace and its automation completely seamless to the production end-user. The technical aspects of this automated furnace loading system are summarized. Functional design and operation of the system are presented, with particular emphasis on the proprietary tooling and software used to detect and compensate for variances in Atmoscan- and shovel-type cantilevers. The system's impact on particle reduction compared to nonautomated furnaces is also discussed. Cost savings resulting from increased efficiencies in Atmoscan tube maintenance, process consistency, automated data collection, and product/operator safety are considered.< >
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