Model Driven Intelligent Control of Manufacturing

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Model Driven IntelligentControl of Manufacturing
Martin Hardwick David Loffredo Blair
Downie info_at_steptools.com STEP Tools, Inc. 216
River Street, Troy, NY 12180 [phone] /
[phone] fax http//www.steptools.com
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Milling, Drilling,Turning
EDM
Contouring
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Who we are

• Mission Use STEP to make the development of
  production processes more time and cost efficient
• 35 reduction in process planning time
• 50 reduction in system costs
• 75 reduction in time to data preparation time
• Forerunners in STEP technology since 1991
• Founders working on product data since 1978
• First commercial software tool kit
• First solid model data exchange using STEP
• Software in gt500,000 CAD stations
• Contributors to STEP and STEP-NC
• Contributor to Parts 14, 21, and 28 of STEP
• Editor of AP 238 (STEP-NC)
• Team leader of ISO TC184/SC4 Wg3/T24
  STEP-Manufacturing

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Problems in current method

• Current process is inefficient
• Design sends incomplete data
• Manufacturing makes fixes but does not document
  them
• End result is a control file that can only run on
  one machine at one supplier
• RS274D is more than 40 years old

CNC Control
CAD
CAM
CL File
IGES
RS274D
Manufacturing
Design
Detailing and Path Planning
Post
Extensive CMM to check the geometry of as-built
parts
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Current NC programming using RS274D
The standard for 40 years!
machine-specific part program with axis data
generated by a postprocessor
N05 G54 N10 G00 Z10.000 N15 G91 G0
Z200 N20 T5 D1 WW N30 G90 M5 N35 G00 X0.000
Y-150.000 N40 G00 Z5.000 N45 M08 N50
S3183.000 N55 M03 N60 F1477.000 N65 G00
X60.000 Y-150.000 N70 G00 Z5.000 N75 G00
X60.000 Y-150.000 N80 G01 Z-0.500 ...
vendor-specific extensions of the original
standard
Ideal for Paper Tape!
only primitive motion and switch commands
no standardized data format for spline processing
and sophisticated NC technology
STEP-NC replaces this with a rich, integrated
data format
Courtesy WZL RWTH Aachen
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STEP-NC is machine independent
workpiece
workplan
geometry
S0?
L0?
machining_feature
machining_workingstep
geometry
1
S0?
pocket
plane
region
hole
machining_operation
1
L0?
plane_milling
side_milling
drilling
tool
technology
toolpath
geometry
1
strategy
cutter_contact_trajectory
parameterised_path
cutter_location_trajectory
Courtesy WZL RWTH Aachen
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Key feature of STEP-NC

• STEP-NC describes what not how
• Make this geometry from this stock
• By removing these features
• In this order
• With these tolerances
• And tools that meets these requirements
• And perform these in-process probing operations
• The old standard described how
• Move tool to this location
• Move tool to this location
• And so on for millions of commands

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AP-238 in context - STEP-Manufacturing
Geometric Tolerances (AP-203 ed2)
Nominal Geometry (AP-203)
Manufacturing features tolerances (AP-224)
Manufacturing Operations (AP-238)
Inspection Data and Results (AP-219)
STEP-Manufacturing Integrates more than 10 Object
models
Equipment Models (AP-2XX)
Applications Include Engineering
collaboration Supply chain management Factory
automation Micro-Machining
There are many important relationships between
the object models
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STEP-NC at NASA JPL

• Rapidly manufacture AP-238 models
• Focus on making ordinary parts on multi-axis
  machines
• Default tolerances and finishes set using Crib
  sheets
• Make ordinary machinists with little CAM training
  competitive with experienced machinists with
  extensive CAM training

Detailing
STEP-NC Control
Pro/E
Fadal CNC with GibbsCAM and ST-Machine
ST-Plan Planning
AP-238
AP-203
Modeling
What are the benefits?
See Next Presentation
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Benefits of STEP-NC
http//www.stepnc.com

• Significant process advantages
• Intelligent machines
• Eliminate post processors
• Reduce scrap using in-process probing

CAD
STEP-NC CNC
CAM Planning
STEP
STEP NC
Manufacturing
Design
75 fewer drawings because electronic data can be
read by browsers (Raytheon)
50 faster for small lots by enabling deployment
of faster, better machines (Cincinnati Machine)
35 faster using 3D feature recognition (Lockheed)
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ST-Plan for Manufacturing

• ST-Plan creates machine independent CNC control
  files
• AP-203 in, AP-238 out
• Tolerance, Feature, Process and Tool definition

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ST-Machine for the operator

• ST-Machine generates tool path data
• Machine independent data converted to machine
  specific tool paths
• Plug-in for a CAM system (MasterCAM, GibbsCAM)

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Open Architecture CNC Controller

• Example application
• Measure feature using probe
• Use probe data to modify finishing pass of
  working step
• Compile tool paths
• Continue

Windows based CNC
Supplied by STEP Tools
Supplied by CAM vendor
Tool Path Compiler
STIX Library
Probing Code
Application Logic
Written for application
Supplied by CNC vendor
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STIX - Properties and Relationships

• Open Source functions to access major concepts,
  relations, and parameters
• In-memory indices and backpointers on the STEP
  data for high speed processing.

Project
stock, shape, material, other parameters
Workpiece
setup
Workplan
Feature
placement, orientation, face geometry, and
other parameters
setup info
Workstep
Path, Profile, Taper, Bottom
machining params
Feature Components
component parameters
Tools
tool characteristics
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STEP-NC Implementation Program

• Implementation program participants show STEP-NC
  can be used to make production parts
• Round 1 2.5D feature milling 6/1/02 to 11/30/02
• Round 2 Surface milling 12/1/02 to 5/31/03
• Round 3 Turning 6/1/03 to 11/30/03
• Round 4 EDM? 12/1/03 to 5/31/04
• Round 2 goals for NIST demo on June 4 and 5

• Start processing surfaces
• Definition as foreign regions
• Processing on the control
• Test Probing
• Casting set-up
• In-process Probing

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Super Model Project (1999 2004)
Industrial Review Board

• GE Fanuc
• CNC Data (Mastercam)
• CADKEY
• Alibre
• Boeing
• General Electric
• General Motors
• Gibbs and Associates (GibbsCAM)
• Hurco Companies Inc.
• Lockheed Martin
• IBM
• NASA (GSFC)
• NASA (JPL)
• NCMS
• Northrop Grumman
• LCMS

• Unigraphics Solutions
• Parametric Technology Corp
• DP Technology (Esprit)
• NIST Intelligent Systems
• Caterpillar
• Lawrence Livermore Laboratories
• DaimlerChrysler
• Watervliet Arsenal (Benet)
• Pratt Whitney
• General Dynamics Land Systems
• Cincinnati Machine
• US Army
• EMPT
• Cambridge Valley Machining
• Honeywell
• RPI

NIST ATP (1999-2002) and Industry Funded
(2002-2004)
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Press Interest
Combined circulation gt 1 million
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How to start the migration?

• In the late 80s Postscript Printers were
  invented
• Microprocessors had enough power for layout
  languages
• Adobe invented the postscript language

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Lessons for Manufacturing

• In the early 00s STEP-NC controls are invented
• Microprocessors have enough power for 3D geometry
• ISO invents the STEP-NC language

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The current process and the new process
30 Month

• Methodology
• Continuously enrich data to enable more STEP-NC
  control reduce costs

Conceptual Design
Set design parameters for new product by
modifying old ones.
Functional Parameters
Make 3D model of product and check parameters
using CAE tools.
Analysis Modeling
CAE
3D Model
Make CAD system independent drawings and annotate
with required tolerances.
Drawing Tolerance
CAD
IGES
NC Path Generation
Makes machine specific process plans using CAM
system.
CAM
RS274D
NC Operation
Obtain tooling and check process plan by single
stepping.
CNC
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Conclusion the ongoing achievement
There are more than one million STEP enabled CAD
stations in the world
The next step is CAM and CNC systems and eventual
ISO 10000 Certification