PowerPointPrsentation

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Case Based, Self Learning Assistant for FEM
Analysis in the Design Process Industry and
Research Project CADFEM Usermeeting 2002 Peter
Binde
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Content
- Dr. Wallner Group - Motivation for a new
Assistant System - Concepts for Knowledge
Reuse - Analysis of Cases from Industrial
Applications - Concept for the Assistant
System - Integration with an CAD/FEM/PDM-System
- State of the Project and open Issues
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Dr. Wallner Group
Consulting and Service around CAD, CAE,
PDM Competences - Process-analyses and
-syntheses - Trainings and workshops -
User-support and hotline - FEA / MKS analysis and
design - Integration-solutions and
software-development
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Dr. Wallner Group
30 Persons, 10 Years Experience Focus on
Unigraphics, iMAN Locations Bremen Wies
baden Stuttgart München
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Motivation for a new Assistant System
Present Situation - More and more FEA becomes
the designers daily work
Deficits - Often special-knowledge is
necessary - Use of different methods for same
problems - Knowledge stays in the heads of
specialists and key users - Examples and
summarised methods are only static - Databases
organize data, but do not know about the content
Solution - Store and reuse knowledge from
existing FEM analysis cases
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Concepts for Knowledge Reuse

• Classification of Systems
• Product configuration systems
• intelligent assembly structures
• Intelligent parts
• Intelligent FEM-models
• Process modellers and wizards
• Guide through a special process
• Systems providing the actual knowledge in context
  to the actual stage of design
• Automatically documenting of included knowledge

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Concepts for Knowledge Reuse Knowledge
Management using Semantics and Features Features
model design characteristics
Example Feature Weld point included
information - Group of involved elements -
Connectivity to geometry - Strength
requirements - Tolerances - Costs - Manufacturing
processes ...
Advantage Weld point can be processed as a weld
point.
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Concepts for Knowledge Reuse Knowledge
Management using Semantics and Features We try
to build up models only by use of features This
method automatically captures knowledge
CAD Features (1) Sketch (2) Revolved (3)
Pocket (4) Pocket (5) Hole (6) Threads
FEM Features Fixed Face Centrifugal
Load Concentrated Mass Stress Tool Fatigue Tool
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Concepts for Knowledge Reuse Rule based versus
case based approaches
Rule based Case based Content
Rules Cases Solving Applying / Finding,
interpreting combining rules and adapting
most similar case Learning Applying new
rules Applying new cases
Novice Applies rules
Expert Applies experience from past cases
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Concepts for Knowledge Reuse Case based
Method Case Based Reasoning (CBR)
Storing a solution in the case base
Focus today
Retrieval of relevant cases
Case Base
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Analysis of Cases from Industrial
Applications About 100 cases are analysed for
their characteristics Goal - Find a way to
classify FEA cases - Find a way to store case
knowledge - Find a similarity measure -
Prove transferability of case knowledge Results
- Classification by design characteristics -
Features describe design characteristics
Hierarchy of design characteristics -
Similarity can be found by comparison of
features - Case knowledge can be
transferred - Result depends strongly on the
use of semantics and features
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Concept for the Assistant System Concept for
the Information-model
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Integration with an CAD/FEM/PDM-System Storing
an analysis case in the case base
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Integration with an CAD/FEM/PDM-System
Retrieving similar cases from the case
base Example Problem Characteristic
Convection on a exhaust pipe 1) User defines the
problem as far as he can by use of CAD / FEM
features, 2) He selects the
interesting characteristics, 3) He asks for
similar cases.
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Integration with an CAD/FEM/PDM-System
Retrieving similar cases 4) The system
searches for similar characteristics in the case
base 5) It shows the datasets of the found
cases in a folder
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State of the Project and open Issues At
present - State of initial Implementation -
Users are limited to consultants of Dr. Wallner
Group - Client server model, based on an
iMAN-Web Portal - Users are allowed to
retrieve cases as well as providing new cases
via the www. Future - Use for
FEM-trainings - Opened for customers
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VIELEN DANK!