260 likes | 448 Views
INTERFERENCE CHECKING. BY Paul Thurber. When is a ½” not a ½”. What do you do if it does not fit Who is responsible for the parts and pieces. History of Drafting. Traditional Paper Drafting Artwork Hard to update Hard to Store . The CAD Revolution. Computerized drafting
E N D
INTERFERENCE CHECKING BY Paul Thurber
When is a ½” not a ½” • What do you do if it does not fit • Who is responsible for the parts and pieces
History of Drafting • Traditional Paper Drafting • Artwork • Hard to update • Hard to Store
The CAD Revolution • Computerized drafting • Faster Drafting • Easier Updating • Easy To Store • Instant Drawings Available
Drafting Practices • Drafter responsible for making parts fit • To insure proper fit tolerances were used • The more accurate the parts the closer the tolerances were required • Locations of features were none standard
Interference Was Engineers Responsibility • Drafters made drawings • Only did some drawings • Complete Assembly • Overall Performance
Tolerance Stacking a Problem • An accumulation of many tolerances a problem • With multiple drawings careful checking needed
No Clear Standards • The World Economy but no World Standards • How TO Convert from Measuring Systems • Quality was Hard to Maintain
Change to Geometric Tolerances • Drafting practices changed • Geometric tolerances were developed • Consistent Drawing Features increases accuracy
Interference Checking • Drafter was now responsible • New standards aided interference • Shop tolerances became standardized
The New 3D CAD • Can now draw in three diminsion • Growing ability to see how parts fit • Multiple views for one part • Solid modeling becomes reality
Animation and CAD • The next revolution was part animation • Exploding parts could be put together • Overall planning and part manufacturing is part of the computer world
CAD/CAM • Computer Aid Design Becomes Computer aid Machining • Drawings become machining programs • Drawings used to automate ordering
Larger Role For CAD • CAD becomes a Major engineering tool • Automation of stresses and design Interference
From the Drawing Into Shop Floor Management • Interference checking goes beyond parts • Shop floor management begins at the design stage • The checking of tolerances is only a small part of the total capabilities
Assembly and Design • Drafting parts with Design Becomes Art Work • Optimization of assembly through animation • Complete Assembly Drawings
Assembly Is Automated • The new CAD/CAM • Becomes point of assembly • Interference checking is automated
Boeing Aircraft • Drafting becomes modular • Can check out designs without parts manufacturing • Computer drafting becomes shop floor management
Tsinghua University • Developed AOPDO • Can make parts to optimize profits • Complete package for Manufacturing
Interference Checking in Assembly • The new programs aid in assembly • Assembly functions can be automated • Each Step is part of whole
Interference Checking Is Quality • The better the fit the higher the quality • Quality is designed into the part • Quality becomes a driving force
Quality is Automated • Interference of Quality needs reduced • Quality is Automated
Winning Customers • Faster modular designs • Customer needs addressed • What is next
Conclusions • Old fashioned is hard to understand • The next step is hard to understand • Can we truly automate manufatcuring
References • “An integrated Framework for the Assembly Oriented Product Design and Optimization” by Qiang Su Ph.D. School of Economics & Management Tsinghus University • “Geo-Metrics II” by Lowell W. Foster • Boeing Aircraft Design Web Page