Increasing Productivity/Quality
through Better Utilization of
Dimensional Data
By
John Reed
www.accurexmeasure.com
Dimensional measurement is accepted as standard
operating procedure
• Geometric Dimensioning and Tolerancing
Geometric Dimensioning and Tolerancing
What do you do with your data after the operator collects it.
Most information is discarded immediately or saved only to be ignored in the future.
Format of the Presentation
•
•
•
•
•
•
Name of the measuring device
Primary Applications
Operating Principle.
System Performance
Typical uses
Example of additional uses
During this presentation we will show examples of output from devices
such as White Light Scanners, Photogrammetry, and data from the
Gap/Mismatch systems. These systems can produce your needed
dimensional measurement information.
We will also use them as examples of how to utilize this data again to
increase productivity and quality
Breuckmann Stereo Scan
GapGun System
TubeInspect
Gap & Flush measuring device
• Primary Applications
Gap/Mismatch Aerospace
Gap/Flush Automotive
Radii & Chamfers
Gap & Flush measuring device
•
Operating Principle.
•
•
•
•
A laser line is projected normal to the surface
Move into operating range
Can use standoffs to center or non-contact mode.
The system will automatically take 16 images of the
laser line using an embedded digital camera.
This line is digitized, the desired calculations made,
nonconforming measurement discarded,
Gap, flush or form displayed and stored
•
•
Gap & Flush measuring device
• System Performance
Operator is shown The measurement is
the correct point to
done.
Measure
Accuracy
Speed
Results displayed
.001” to .004”
Up to 8 features per minute
Result recorded
Gap & Flush measuring device
•
Typical uses.
operator performs the measurement, the results
are shown (green or Red) of PDA and recorded on an Excel spreadsheet
to be viewed. The trend comparison from the last several pieces can be
seen and the data archived.
•
•GapGun sample output
Gap & Flush measuring device
• Example of additional uses
Nissan Motors System is on-line taking between 16
to 32 features. They are using multiple Gap/Flush
measurement devices connected to the same computer
and program.
• The operator gets immediate feedback and results are
put into an SPC pack for long-term evaluation.
• The results for each vehicle will be displayed to the
area assembling components giving them a running
real-time indication (within a few minutes) for the
consistency of the work.
Gap & Flush measuring device
• Example of additional uses
• Lockheed Martin.
Every F35 contains a number of gap/mismatch measurements.
Lockheed developed a system to store all data from every plane. After a number of planes are
manufactured it is possible to look at all the dimensional data on each plane to include
gap/mismatch in an attempt to correlate changes in performance to the dimensional variance.
•
F35 JFS
F35 JFS Checkplan
White Light Scanner
• Primary Application.
Creation of point cloud (2 to 200
million surface points). Free-form shaped parts or parts with many small surface
features. To be used for inspection, comparison to cad or reverse engineering for
small to mid size parts
Scans (unfinished) part
Scans finished
White Light Scanner
•
Operating principle.
Structured light is projected (a series of
lines) onto the surface. There is a known angle and distance between the
projector and the camera(s). This allows triangulation to be used to calculate the
surface points allowing several million surface points created in a few seconds.
Topometric Data Acquisition and Evaluation
Topometrical Setup with
Miniature Projection-Technique ( MPT )
MPT-projector
triangulation angle
Image recording with combined GrayCode- / Phaseshift-technique ( about 1 s )
evaluation of the image sequence
MPT-projector
digital camera
digital camera
calculation of
3D-coordinates
optoTOP-HE
How a White Light Scanner Works
Matching ( STL-data )
GrayCode
Phase image
Example of results
Fringe contrast
White Light Scanner
•
System Performance.
•
The size of each scan can vary from ½ inch square to 60” square.
The scan time (2 seconds) and the number of points remain the
same. The accuracy .0002” to .020” and the resolution will change
as the field of view increases (.1/2” to 60”). Multiple scans can be
merged together to create a point cloud.
White Light Scanner
• Typical applications:
Applications vary widely. It is used in
industrial applications such as turbine blades, dashboards, molds and dies. It is also
used in measuring skin roughness, artifact preservation, art, and in a number of other
industries
reverse engineering projects
engineering projects and feasability studies
Blaser Jagdwaffen - Hunting Weapons
Cultural Heritage
Snecma/IBS/Clever Engineering – Aircraft and Space Engines
Smithsonian Institution / Accurex – Largest Museum Complex Worldwide
Development of an Adaptive Grinding Process
Deer Stones Project in Mongolia
Until now the airfoil area is measured on a multi
tactile measuring machine.
ƒ Measuring of prototype rifle stock
models
ƒ
ƒ
Reverse engineering
Milling out of precious root wood
Thursday, 16 October 2008
www.breuckmann.com
www.breuckmann.com
Reverse Engineering
Thursday, 16 October 2008
www.breuckmann.com
www.breuckmann.com
Inspection of complex parts
Thursday, 16 October 2008
www.breuckmann.com
www.breuckmann.com
Cultural preservation
Mold Measurement Using a
White Light Scanner
• Example of additional uses
•
•
•
•
•
•
Scanning a die.
Both halves of the die are scanned and the results can be
compared.
This information can also be given to an operator to hand repair the
die
For better utilization, use the model and data and analysis in
package such as Polyworks for more options to best fit the data.
For example, the error can be shifted around to permit a decrease
of the hand sanding or the wielding. Another option is to optimize
the work to allow for longer life of the die before it needs be
Next slide for examples
Mold Measurement Using a
White Light Scanner
PolyWorks/Inspector
PolyWorks/Inspector
Process Overview: Left Die vs Draw CAD
Feature-Based Alignment
1
vs
Best-Fit Alignment
Data
Alignment
3
CAD
2
Initial Stage:
Aligned
Data & CAD in two different
coordinate systems
1st: 4-Way Locator
3rd: Reference Points (3) in
2nd: 2-Way Locator
the y axis
Report the results
Comparison
reworked
Hemmer Die Right versus Inner Panel CAD
and Upper Frame CAD
Door after left Die 2-34 versus
Inner Panel CAD
Optimization thru best fit
Color deviation diagrams
Mold Measurement Using a
White Light Scanner
Example of additional uses
•
Another possibility is to output the data to a laser projection system
where it will projects different colors on the sections of the die needing
work, thereby showing the hand grinding operator exactly where and how
much material needs to be removed. This will increase the productivity of
the machinist working on the repair.
Color deviation diagram projected on part
Bent Tube Inspection by a
Photogrammetry System
•
Primary application.
Dimensional Inspection of bent
tubes, hose and attachments made with a CNC bender.
Theoretical tolerance zones of a typical bent tube.
Bent Tube Inspection by a
Photogrammetry System
•
•
•
•
•
•
•
•
•
The operating principles.
Enclosure that houses 8 to 16 CCD cameras
Light table with embedded photogrammetry target.
The bent tube is placed on the table in a free
(unrestrained) state.
Each camera then takes an image in approximately 30
milliseconds.
The system digitizes the profile of the tube
Using the photogrammetry targets, the system merges
all the images together to create a 3D model.
The model is put into a simulated restrained condition
to take out the effects of gravity.
Creates an inspection report.
Bent Tube Inspection by a
Photogrammetry System
Basic Principle
Images from 16 digital cameras
Basic Principle
Work Flow Optical Gauge
Creating 3D model and bending points
The Parts are place in the TubeInspect
Printout of deviation report
Images are merged
Inspection Results
Bent Tube Inspection by a
Photogrammetry System
•
System Performance.
•
•
•
•
Bent tubes or hoses from 1/8” to 8” Diameter
length is unlimited
Accuracy is .001 to .004.
The system can measure an 8 foot tube with
20 bends in 15 seconds.
Sampling rate of thousands of points,
increasing the reproducibility.
•
Bent Tube Inspection by a
Photogrammetry System
•
Typical application.
•
Application in aerospace or automotive tube or tube assemblies
(with hoses) coming from a CNC tube bender are typical
applications
.
Theoretical tolerance zones of a typical bent tube.
Bent Tube Inspection by a
Photogrammetry System
• Example of additional uses
• Take the measurement data, Correction
can be sent to the CNC bender.
Work Flow Bending Program Set Up
Work Flow Bending Program Set-up
Generate correction data
Send set-up data to machine (RS232, TCP/IP)
SERVER
SERVER
tube
info
deviation
values
control
panel for
datatransfer
PBR correction are automatically calculated
Bender
1
Bender
2
Bender
3
Bender
4
Corrections are sent to the CNC bender
Bent Tube Inspection by a
Photogrammetry System
• Example of additional uses
•
•
•
•
•
Typically after the tube is bent, it is measured and the excess length
is hand marked on the tube.
It is then hand trimmed on a saw with the operator positioning each
end as close a possible to the hand marked location.
TubeInspect can use the existing measurement data and
automatically calculate the amount of tube to be removed.
Automatically positions a motorized stop behind the saw in order to
put the tube in the correct location.
The operator then takes the tube out of the TubeInspect, puts the
first end of the tube against the backstop, cuts off the end, and
rotates the tube before repeating on the opposite end.
Basic Single Camera
Photogrammetry
• Primary application.
•
•
•
Create small point clouds
to be used for large or difficult to reach
part measurements
measure deformation on parts due to
temperature, weight or position changes.
Basic Single Camera
Photogrammetry
•
Operating principle. Reflective photogrammetry targets are
placed on the desired measurement object at each location where a
recorded point is needed. A reference bar is placed in the measurement
field with two targets of known distance. A special digital camera is used to
collect the images, which are digitized and downloaded to a computer. A
point cloud of these points is created, which can be used for feature
measurement or compared with an earlier survey to establish deformation
Z
5
4
Y
X
1
Photogrammetry
equipment
2
3
The theory of Photogrammetry
camera positions
Example output
Basic Single Camera
Photogrammetry
•
•
•
System Performance:
1” to several hundred feet.
Accuracy is from .0002” to .010”.
Basic Single Camera
Photogrammetry
• Typical application.
•
•
Measure primarily free-form surfaces or forms on large parts.
Measure deformation due to Gravity or Temperture
Antenna prepared for survey
Color deviation diagram of antenna
Basic Single Camera
Photogrammetry
Additional photogrammetry examples
•Large Fabricated Part
Large round free standing case
Basic Single Camera
Photogrammetry
• Example of additional uses
•
By adding cubic target to your target list you can measure geometric
features much easier. These points can be automatically downloaded to a
software design for easy comparison between the measure data (features)
and the nominal through the use of CAD, which also generates an
inspection report.
Standard flat or paper reflective targets
New style cubic feature target
Closing Summary
• These descriptions of additional usage for dimension
measurement are examples of benefits that can be
achieved with the extra step of utilizing the dimensional
measurement data already collected. The goal of this
paper is to give pertinent examples of how to better
utilize your data. Since applications and requirements
vary widely you may not be able to use these exact
examples. However, it can serve to enable various
problem-solving approaches for uncovering how this
data can improve your production/quality with various
applications and data collection systems.