Transcript Appication of PHG - Torsten Braeuer.ppt

Unternehmung
WENDELSTEIN
7-X
Photogrammetry at WENDELSTEIN 7-X
Max-PlanckInstitut für
Plasmaphysik
Application of Photogrammetry
during Construction of W7-X
T. Bräuer
Content: How Photogrammetry works?
Photogrammetry Equipment at IPP Greifswald
Examples of Photogrammmetry
Summary, Conclusion
Torsten Bräuer
Meeting with NCSX, Greifswald, 10.10.2007
1
Unternehmung
WENDELSTEIN
7-X
Photogrammetry at WENDELSTEIN 7-X
Max-PlanckInstitut für
Plasmaphysik
How Photogrammetry works?
Part 1: Principle
Position 1
Position 2
Position 3
1. Taking a picture from a first camera position
2. Calculation of first camera position from
points known (4 pieces; green lines) in the
initial co-ordinate system (blue)
3. Calculation of line of sight to New-Points (red
lines)
4. Taking pictures from additional camera
positions
5. Repetition of step 2 & 3 for the additional
camera positions
6. Calculation of the cross section of the line of
sights to a New-Point and calculation of the 3D co-ordinate
7. Finally: Bundle Block Adjustment
Torsten Bräuer
Meeting with NCSX, Greifswald, 10.10.2007
2
Unternehmung
WENDELSTEIN
7-X
Photogrammetry at WENDELSTEIN 7-X
Max-PlanckInstitut für
Plasmaphysik
How Photogrammetry works?
Part 2: Marking of Points
Surface point: Retro reflex foil
Ø=10mm
• Signalization is made by
retro reflex targets
• Surface points: retro
reflective foils (sticky foil)
Ø=10mm
Adapter for fitted holes
Ø=8mmH7 with retro reflex target
Torsten Bräuer
• Primitive geometries:
Adapter for
• Fitted holes
• edges
• corners
• …
Meeting with NCSX, Greifswald, 10.10.2007
Photogrammtry camera
with ring flash
Example picture of retro
reflective targets with its
very high contrast
3
Unternehmung
WENDELSTEIN
7-X
Photogrammetry at WENDELSTEIN 7-X
Max-PlanckInstitut für
Plasmaphysik
How Photogrammetry works?
Part 3: Identify target points with numbers
• Each object point has to has the
same number in all pictures!
• Coded points are recognized by
software image processing
• Starting from a minimum of 6
coded points per picture it is
possible to name all New-Points of
a picture unique
Torsten Bräuer
Meeting with NCSX, Greifswald, 10.10.2007
4
Unternehmung
WENDELSTEIN
7-X
Photogrammetry at WENDELSTEIN 7-X
Max-PlanckInstitut für
Plasmaphysik
Photogrammetry-Equipment at IPP Greifswald
Measurement system:
• 2 x Camera Nikon DX1
with ring flash
24mm lense
20mm lense
• 1 x initial cross
• 2 x scale bars 1390mm
• 512 x coded targets
Targets:
• Sticky foil Ø=10mm for surface
• Targets for Ø=8H7 holes
Software:
• AICON 3D-Studio with
• Image analysis and coordinate calculation
• Deformation analysis
Torsten Bräuer
Meeting with NCSX, Greifswald, 10.10.2007
HUBBs-targets
Crossing point
with Offset (usually 25mm)
vector-targets
ball-targets
3-point-targets
feature-targets
1.5”-CCR-equivalent
5
Unternehmung
WENDELSTEIN
7-X
Photogrammetry at WENDELSTEIN 7-X
Max-PlanckInstitut für
Plasmaphysik
Installation of
Photogrammetry
targets
Examples of Photogrammetry
Part 1: Incoming inspection of a coil
Ca. 150 New-Points per coil
Standfuß 1
Comparison Photogrammetrie
and Laser-Tracker:
• 12 reference points
• RMS = 0.118 mm
Montagestütze 1 u. 2
Messpunkte
Ca. 3.5m
Druckstütze 2
Zentralstütze 1 u. 2
Planarstütze 1
Standfuß 2
Coil and its Ref.-points
Torsten Bräuer
Survey of coil with
Photogrammetry
and Laser.Tracker
Meeting with NCSX, Greifswald, 10.10.2007
6
Unternehmung
WENDELSTEIN
7-X
Photogrammetry at WENDELSTEIN 7-X
Max-PlanckInstitut für
Plasmaphysik
Examples of Photogrammetry
Part 2: Survey of coils in assembly stand
• ≈ 480 pictures necessary
• 83% resp. 95% of points of a coil
are visible
• Transformation into assembly
stand resp. coils co-ordinate
system
RMS = 0.13 mm
• Maximum position deviation
< 1.2 mm
• proof, that measurement
accuracy required can be
reached
• proof, that adjustment accuracy
required can be reached
Torsten Bräuer
Meeting with NCSX, Greifswald, 10.10.2007
7
Unternehmung
WENDELSTEIN
7-X
Photogrammetry at WENDELSTEIN 7-X
Max-PlanckInstitut für
Plasmaphysik
Summery / conclusion
• Repetition measurement uncertainty of Photogrammetry is better than
0.1…0.15mm in a volume of 5x5x5m³
• Photogrammetry is appropriated for complex components with a high
number of target points
• A high number of target points on a component means a high
probability to get enough lines of sight
• Photogrammmetry do not need rigid stand points for the measurement
system
• For 4 or more coils assembled in assembly stand Photogrammetry
needs less on-line time for a survey than other survey technique (for
instant Laser-Tracker)
-----------------------------------------------------------------------------------------------• Photogrammmetry needs off-line post processing time
• Adjustment off components using Photogrammetry needs a lot of
affords or is impossible
Torsten Bräuer
Meeting with NCSX, Greifswald, 10.10.2007
8