ISSN:0020-7543    

DOI:10.1080/00207548808947969

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

CAD systems and other planning instruments are used more and more in designing manual and partly automated work systems. Ergonomic aspects are often not taken into consideration because of a lack of usable ergonomic design instruments. On the other side, a planning system for the dimensional designing of movement facilities was developed and used with success in West Germany—theVideo Somatography.In connecting the two different systems, a new integrated ergonomic system was created. Thereby workplaces can be planned and designed using ergonomic and technical criteria in an optimal way. Further advantages are expected by integrating ergonomic knowledge into the system. With this, it will be possible for the workplanner to get information about ergonomic and economic conditions (workload, strength, assembly duration, etc.)

ISSN:0020-7543    

DOI:10.1080/00207548808947970

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

The future-oriented concept of computer-integrated, flexibly automated manufacture reveals the first convincing results at present. They indicate a fundamental change of production modes. Due to the transition from order-neutral manufacture to manufacture bound by order, targets are developing that have to be met by flexible solutions of process automation of a new type. Finally, in order to achieve high flexibility of manufacture, monitoring and control strategies of a new type have to be developed. Tool monitoring is the focus of process monitoring. This will be shown by raised technological machine intelligence of flexible automated turning cells with the main components of sensor systems, control concept and process models for monitoring and control strategies. The process invariance to be aimed at for process monitoring now involves the development of such strategies applicable for a maximum value range of a maximum number of process, tool and machine tool parameters. For adaptive control systems at machining cells, the actual available machining time mentioned has to be included into the technological process model as a basis for self-optimization

ISSN:0020-7543    

DOI:10.1080/00207548808947971

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

The typical factory automation system contains a number of programmable automation devices such as robots, automatic storage/retrieval systems (AS/RSs) and automatically guided vehicles (AGVs). Real-time control system software (RTCS) is needed for integrating these devices into a synchronized manufacturing system (SMS). However, development of this RTCS software could be hampered by excessively long software development backlogs which are currently averaging about 30 months in the typical US corporation. This paper presents a structured methodology for the development of the specifications for such software. This methodology is illustrated by applying it to an automated system for producing highway traffic signs. This system consists of an assembly robot with an automatic tool changer, an AS/RS and a reciprocating table

ISSN:0020-7543    

DOI:10.1080/00207548808947972

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

This paper derives two formulae to calculate the average inventory yielded by fixed interval withdrawal Kanban and supplier Kanban, respectively, in a just-in-time production system. By using the formulae, another two formulae to determine the minimum number of Kanbans to be required for the fixed interval withdrawal Kanban and the supplier Kanban are also shown. An algorithm to obtain the optimal order interval is proposed to minimize the total operation cost composed of the inventory cost and the withdrawal cost for the Kanban system

ISSN:0020-7543    

DOI:10.1080/00207548808947973

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

A new active error compensatory method for on-line cutting control has been developed for reduction of the form errors in machining. This approach is a combination of in-process gauging and model active compensatory control. In this approach, there are two features of substantial importance: stochastic modelling and optimum forecasting. Through stochastic modelling, the cutting tool error motions can be represented by a simple model without the necessity of obtaining the complex cause-and-effect relationships between various errors and error sources, and more importantly, it is possible to account for both repeatable and non-repeatable parts of errors. Optimum forecasting is an important prerequisite for a rational control strategy, considering the inevitable time delay associate with sensing, computation and actuation. The proposed control method was implemented for the control of cylindricity in boring operations. Through the controller simulation based on experimental measurements, the improvement in cylindricity accuracy confirms the effectiveness of this proposed strategy

ISSN:0020-7543    

DOI:10.1080/00207548808947974

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Process performance is very dependent upon the unique characteristics of the process equipment and the work/tooling interactions. To address this problem, research has been conducted to explore the feasibility of using an intelligent supervisory controller to build a local process database and provide control for the process. The research concerns the milling process as used in a machining centre. This paper will report on the data analysis, proposed control approaches, and how these results relate to the intelligent supervisory controller

ISSN:0020-7543    

DOI:10.1080/00207548808947975

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

The concept and method of diagnosing the regenerative chatter are discussed in this paper. Both theoretical analysis and experimental results demonstrate that a certain corresponding relationship between the system stability and the phase shift angle ψ in the two wavy surface: one from the previous cut and another from the current cut, and hence, one can identify whether the chatter occurring in the cutting process is a regenerative chatter. The phase shift angle ψ is concerned with the chatter frequency and the rotational speed of the workpiece. In order to improve diagnostic accuracy, digital ZOOM FFT has been applied

ISSN:0020-7543    

DOI:10.1080/00207548808947976

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Production planning in flexible manufacturing requires the updating of work schedules each time a new product order is acquired. To this end, a Production Planning (PP) strategy should be devised by solving two coupled problems, embedded into an iteration: (i) Product Orders Scheduling, (ii) Production Capacity Planning. This paper presents a new algorithm to solve the Production Capacity Planning (PCP) Problem for a complex manufacturing system composed of a network of bufferized time-sharing workshops (i.e. shops able to share their service rates among different part types). The solution procedure developed allows one to minimize the Global Flow Time (GFT), while verifying service and storage capacity constraints, in association with a given future pattern of product orders. An example derived from an existing production process is outlined, to show the effective usefulness of the proposed PCP procedure, and its easy integration with existing scheduling tools

ISSN:0020-7543    

DOI:10.1080/00207548808947977

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

In order to gain better understanding of the effect of pre-aging on the tensile properties of 6201 Al alloy, different TAHA processes have been performed in this study. A 6201 AI alloy was first solution treated, followed by pre-aging at 135°C for 30 minutes (some specimens were without pre-aging). The specimens were then cold rolled to 60, 70 or 80% reduction in thickness followed by final aging at 140, 150 or 160°C for 1 to 20 hours. For specimens of 60% cold reduction, the ultimate tensile strength (UTS) and yield strength (YS) were significantly improved by pre-aging. The improvement in strengths by pre-aging was most (least) significant if the final aging temperature was 140°C (160°C). For specimens of 70% reduction, the improvement in UTS and YS by pre-aging was not as significant. For specimens of 80% cold reduction, lower strengths were found for pre-aged specimens as compared to specimens without pre-aging. Scanning electron microscopy revealed that there was close relationship between the fracture morphology and the resulting tensile properties. Proper combination of pre-aging and cold work led to finer, denser and more uniform distribution of precipitates which resulted in better tensile properties

ISSN:0020-7543    

DOI:10.1080/00207548808947978

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor