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Faculty of Mechanical Engineering and Naval Architecture
Development of a Development of a SSystem for ystem for CConcurrent oncurrent EEngineering ngineering AAssembly ssembly PPlan lan
GGenerationeneration
Zoran KUNICA, Ph.D., Assistant Professor
Professor Božo VRANJEŠ, Ph.D.
Miljenko HRMAN, B.Sc., Postgraduate student -- trainee
University of Zagreb
Croatia
Section:Section:ISMS 2001:ISMS 2001: Processes and SystemsProcesses and Systems
Third International ICSC-NAISOWORLD MANUFACTURING CONGRESS
April 2-5, 2002, Rochester, New York, U.S.A.
INTROINTRO
The most of the products have more than one part... so they must be assembled.
The goal of the research: development of CAE component that would allow more efficient assembly planning in the effort to integrate:
• the product design,• assembly system design.
The motivation of the research:• upgrading the assembly system planning methodology,• development of the computer support for planning.
Recent explorations:• the necessity of assembly and assembly-related knowledge
synthesis, compilation and integration (concurrent engineering);• automatic vs. interactive process/system generation;• variants and combinatorial complexity;• shift of interest to still uncovered aspects of the human process
planning, which is intuitive to a great extent.
22
33
The Production PILOT, still developing suite of products, consists of assembly process design, simulation, and analysis tools, built into 3-D graphical environment, and seems to be good example of future trend of development and practice (SILMA, 2001).
ASSUMPTIONSASSUMPTIONS
44 Assembly process/system planning
a product -- an assembly, exists as CAD model assembly and disassembly are inverse issues a product is a virtual mechanism, that should be recognized during
planning stage an assembly system is a complementary mechanism
non-standard components
PRODUCT (ASSEMBLY)
ASSEMBLY SYSTEM
standard components
mechanism I – assembly paths
mechanism II – components` motions
PLAN GENERATION SYSTEM & ELEMENTS
55
SOME PLAN ELEMENTSSOME PLAN ELEMENTS
For an automatically generated initial disassembly sequence, instead of the criterion distance of the part centre of gravity from the product centre of gravity, the combination of three criteria is used:
• distance of the part centre of gravity from the product centre of gravity,
• the value of y component of the part centre of gravity,
• part volume (mass).
66
One criterion...
The improvedalghorithm – three criteria...
The example of advantages of using combination of criteria for initial disassembly sequence...
the main part
77
EXAMPLES OF PLAN GENERATIONEXAMPLES OF PLAN GENERATION
Microsoft PowerPoint Presentation
99
DEVELOPMENT OF THE ASSEMBLYDEVELOPMENT OF THE ASSEMBLYPLANNING SYSTEMPLANNING SYSTEM
An assembly planning environment should combine tools distributed in two levels:
1. pretools within activities prior to assembly planning,
2. assembly planning CAE component (posttool) that follows product design process.
Assembly planning and activities of product design 1010
Discrepancy in orientation: natural orientation of the part (A), technological orientation (B), orientation required in a product (C)
1111
Origins of orientation definition
1212
Example of definition of plan generation parameters
ASSEMBLY PLAN GENERATIONOPTIONS
ASSEMBLY PLAN GENERATIONOPTIONS
Automatic generation Onof assembly sequence Off Off
Automatic generation Onof assembly sequence Off Off
Connectivity Oncheck Off OffConnectivity Oncheck Off Off
.
.
....
Automatic generation Onof assembly system layout OffOff
Automatic generation Onof assembly system layout OffOff
Product class Product class
1313
Planning procedure should be analysed as a combination of automatically and interactively generated elements.
A concept of the intelligent assembly system development
1414
INTELLIGENT ASSEMBLY SYSTEM DEVELOPER
PROCESS STRUCTURE
DEVICES
CATALOGUEstandard
componentsOPERATIONS
DEVOTERnon-standard components
SYSTEM INTEGRATOR
ADJUSTING OF DEVICE DESIGN
Thompson's examples of variations of living organisms
(1917)
Variants/variations of productsVariants/variations of products
Duerer's examples of variations of living organisms
Two solutions of the same mechanism (Blanding,
1999)
1515
1 Product
2 3 4 5 6
[1, 0, 0, 0, 0
[1, 1, 1, 1, 1
[1, 2, 2, 2, 2
[1, 0, 0, 1, 2
1616
Some of the structures for a product with six parts (Beneath the graphical presentation of each structure the structure’s numerical code is given.)
Variations of assembly processVariations of assembly process
The assembly process can be represented and modelled using generic structures – generic plans.
The structures show the space and time possibility of the assembly process realisation.
xz – horizontal plane
Variants of product`sVariants of product`s initial oinitial orientarientationtion
Hi6Hi6
Hi5Hi5Hi2Hi2
Hi4Hi4
Hi3Hi3
1717
Variants of Variants of pparts’arts’ layoutlayout
Rotary-table(D = 1234,212 mm)
Line assembly(L = 8639,487 mm)
.Hi5
Hi4
Hi2
Hi3
Hi6
z distance Hi5-Hi6:
5924,22 mm
1818
Variants of equipmentVariants of equipment’’s s manufacturermanufacturer
ABB IRB 140
2020
FANUC LR Mate 100i AdeptSix 300
Variants... variants... etc. ...Variants... variants... etc. ...
FURTHER WORKFURTHER WORK
Experiments with concurrent generation of assembly plans.
Modelling of CE planning situations and roles (procedures, protocols and data sharing).
Analysis and optimisation of (dis)assembling paths (directions, lengths).
Simulation of assembly operations and assembly techniques (forces, deformable joints - snap fitting, ...).
Assembly device design and development of a CAD catalogue of devices.
Human planner's mental activities and behavior -- conscience and non-conscience (intuitive) aspects of the planning.
2121
S. FreudS. Freud
&&
Eric Berne`s Eric Berne`s transaction transaction analysisanalysis