外文翻译!!!!!.docx

???Rapid?Prototyping?and?manufacturing??Introduction?????The?term?“rapid?prototyping”?(RP)?is?a?relatively?new?expression?for?the?generation?three-dimensional?models?manufactured?without?the?need?for?machining?or?products?designed?on?a?computer?aided?design?system,?the?first?rapid?prototyping?system?was?introduced?on?to?the?US?market?in?1988?and?gave?the?engineer?the?opportunity?to?produce?3?dimensional?objects?directly?from?Computer?Aided?Design?(CAD)?date?and?succeed?in?the?cost-effective?production?of?patterns?and?moulds?with?complex?surfaces.?????The?principle?advantages?of?using?this?technology?are:??High?speed?at?which?the?solid?model?is?generated.??The?complexity?of?the?model?does?not?form?any?limitation?to?its?production.??The?early?use?of?these?models?was?to?assist?the?designer?in?determining?fitness?and?form.?It?also?provided?the?sales?team?with?a?3?dimensional?object?to?show?to?a?prospective?customer,?this?being?far?better?than?the?traditional?orthographic?drawing?which?many?people?find?difficult?to?nterpret.?The?benefits?of?RP:??1.Converts?3D?CAD?images?into?accurate?physical?models?at?a?fraction?of?the?cost?of?traditional?methods.??2.Improves?design?communication?and?helps?eliminate?design?mistakes.??3.Reduces?“time?to?market”?for?a?new?product.??4.Can?be?used?as?a?powerful?marketing?tool?since?the?prototype?can?be?seen?rather?than?the?drawing.??5..The?development?of?this?technology?has?reached?into?many?of?the?traditional?fields,??attracting?the?interest?of?artisans?whose?skill?any?knowledge?has?led?to?3-D?objects?being?used?directly?and?indirectly?as?patterns?and?model?for?soft?tooling.???6.Production?of?models?by?machining?has?a?number?of?limitations.??7.?Material?removed?during?forming?is?difficult?to?reclaim.???8.Machining?in?the?form?of?drilling?turning?milling?spark?erosion?etc.,?is?limited?by?the?shapes?it?can?produce.??9.In?the?event?of?design?change,?conventional?tooling?such?as?patterns?,core?boxes,?dies,?jigs?etc.?,become?expensive?to?alter?