Benefiting from advances in feature technology for design and manufacture can not be expected before a formal methodology is established. This paper makes attempt to establish a definition formalism of machining featu...Benefiting from advances in feature technology for design and manufacture can not be expected before a formal methodology is established. This paper makes attempt to establish a definition formalism of machining features in design for manufacturability from two aspects: formal definition and manufacturability analysis. Some definitions for machining feature based upon the selection and sequencing of material removal operations for component in accordance with the design geometry are presented and a framework of feature based design for manufacturability is outlined correspondingly. The proposed scheme contributes to several aspects of feature based CAD/CAM integration, especially to encourage potentially a more generic approach to the automation of design.展开更多
The TangShan Research Institute of Group Technology has been engaged in the develop- ment of GT for the light industry machinery building factories since 1980.Under its overall supervision more than 8 factories have a...The TangShan Research Institute of Group Technology has been engaged in the develop- ment of GT for the light industry machinery building factories since 1980.Under its overall supervision more than 8 factories have applied GT to drawing control and process planning,while 4 of them reorga- nized their machine shops into GT cells and the throughput capabilities were raisd immediately by 15 to even 49%. Since the existing GT coding systems predict only the global characteristics of machine parts,their application alone is unable to transfer all the information needed for the CAD/CAM integration in a CIM environment.From the very beginning of 1989,we started to study the feasibility of introducing concepts of Functional Form Features into GT codes.Based on the exhaustive study of nearly 100,000 part drawings from machineries for making pottery and porcelain appliances,cigarette,paper pulp, glass bottles,plastics moulding,beer and beverage filling etc.,a new GT/FFF coding system was worked out and a corresponding set of standard drawings assembled from FFF primitives Was formulat- ed which can cover up to 65—75% of existing parts from light industry machineries.FFF based GT codes greatly facilitate the standardization control of released drawings,accelerate the engineering de- sign and process planning,and certainly will play an important role in the future CIM organization.展开更多
The world has entered an era featured with fast transportation, instant communication, and prompt technological revolution, the further advancement of which all relies fundamentally, yet, on the development of cost-ef...The world has entered an era featured with fast transportation, instant communication, and prompt technological revolution, the further advancement of which all relies fundamentally, yet, on the development of cost-effective energy resources allowing for durable and high-rate energy supply. Current battery and fuel cell systems are challenged by a few issues characterized either of insufficient energy capacity or of operation instability and, thus, are not ideal for highly-demanded applications, such as electrical vehicles and portable electronic devices. Inefficient mass transfer in energy conversion/storage devices has been the key factor leading to these aforementioned challenges.展开更多
文摘Benefiting from advances in feature technology for design and manufacture can not be expected before a formal methodology is established. This paper makes attempt to establish a definition formalism of machining features in design for manufacturability from two aspects: formal definition and manufacturability analysis. Some definitions for machining feature based upon the selection and sequencing of material removal operations for component in accordance with the design geometry are presented and a framework of feature based design for manufacturability is outlined correspondingly. The proposed scheme contributes to several aspects of feature based CAD/CAM integration, especially to encourage potentially a more generic approach to the automation of design.
文摘The TangShan Research Institute of Group Technology has been engaged in the develop- ment of GT for the light industry machinery building factories since 1980.Under its overall supervision more than 8 factories have applied GT to drawing control and process planning,while 4 of them reorga- nized their machine shops into GT cells and the throughput capabilities were raisd immediately by 15 to even 49%. Since the existing GT coding systems predict only the global characteristics of machine parts,their application alone is unable to transfer all the information needed for the CAD/CAM integration in a CIM environment.From the very beginning of 1989,we started to study the feasibility of introducing concepts of Functional Form Features into GT codes.Based on the exhaustive study of nearly 100,000 part drawings from machineries for making pottery and porcelain appliances,cigarette,paper pulp, glass bottles,plastics moulding,beer and beverage filling etc.,a new GT/FFF coding system was worked out and a corresponding set of standard drawings assembled from FFF primitives Was formulat- ed which can cover up to 65—75% of existing parts from light industry machineries.FFF based GT codes greatly facilitate the standardization control of released drawings,accelerate the engineering de- sign and process planning,and certainly will play an important role in the future CIM organization.
文摘The world has entered an era featured with fast transportation, instant communication, and prompt technological revolution, the further advancement of which all relies fundamentally, yet, on the development of cost-effective energy resources allowing for durable and high-rate energy supply. Current battery and fuel cell systems are challenged by a few issues characterized either of insufficient energy capacity or of operation instability and, thus, are not ideal for highly-demanded applications, such as electrical vehicles and portable electronic devices. Inefficient mass transfer in energy conversion/storage devices has been the key factor leading to these aforementioned challenges.