1. Geometric Model Schema
?ラ採庁侏c cadcam 議PS
( Geometric model with CADCAM)
?ラ採庁侏議圻尖c格F
(Principle and Visualization of Model)
?ラ採庁侏議喘I囃
(Application Field with Geometric model)
?ラ採庁塀初c箭
(Introduce to Geometric Model)
2. ラ採庁侏c CADCAM 議PS
CAD PROCESS ON CADCAM SYSTEM
?O庁塀 In a draw :Shape,material,surface condition,
dimensions,manufacturing.
In a diagram:structure,system arrangement
?O庁塀
喘
Design evaluation:form, kinematic ,strength
Manufacturing:Processing planning,NC
program.
?揖化垢殻 Teams,fast change,short lead time,high quality
Computer Aided Design
5. ?1959 定 P. d e C a s t e l j a u 壓 1959 定_兵W壓爆式爆中議O
r麿蚪F廿垢恬
?隈繁 P. B └ z i e r 壓跡Z廿l婢阻 Unisurf 狼y
?60 定旗 J. Ferguson 壓襖咄巷望眉肝紗秘阻O議狼y
?1974 定q麿巒議匯冩貧屎塀∂@I囃Q蕁焔Xo廁ラ採
O
?B-spline 議尖a伏児A麼勣轅 Mansfield 、 de Boor 才 Cox 吉
繁
?70 定旗喇豢 W. Gor don 才 R. Riesenfeld 議冩l聞誼 B-spline
議爆式爆中_兵紗秘 CAD 議ラ採宰伉嶄
?B-spline φ CAD I囃l伏阻載寄議n遙參 B-spline 児A議
凪万尖匆ma伏泌眉叔侘議爆中K (triangular patches) 才爆中蛍
護 (subdivisionsurfaces) 吉
?除ラ定蹌喇豢 NURBS(Nonuniform Rotational B-spine ) 爆中頁匯
掲械挫喘議爆中庁侏侭參參 NURBS 藥A議 CAD/CAM 狼y匆_
兵l婢欺阻 1983 定 NURBS _兵紗秘 IGES(initial
graphicsexchange specification) ク騏弌
ラ採庁侏初 Geometric Model
6. ラ採庁侏初
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? B └ z i e r CURVE
Q岻 Bernstein 謹塀児久
}0|),{( niyxP iii <<=
爆頁喇隈
垢殻 Pierre
Bezier 阻盾Q廿
議LD}
侭戻竃議圭隈 . 凪
豢匯爆議宙峰
圭隈 .
戻竃議圭隈 , 淫凄
cubic
spline , 麗∈老
(parabolic blending),
B-spline 吉 , @乂爆
燕幣隈寄脅鞭
溲怯罹宥^侭嗤
c , 咀緩搆暁
M栽 (curve fitting)
9. ラ採庁侏初
?B └ z i e r Surface
ij
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(m+1)*(n+1) 陣崙c鹿
15. Definition of geometric modelDefinition of geometric model
Definition translatorDefinition translator
Geometric modelGeometric model
Interface algorithmsInterface algorithms
Design and analysis algorithmsDesign and analysis algorithms
Drafting and detailingDrafting and detailing
DocumentationDocumentation
To CAM processTo CAM process
Design change