GBS_smartWLI Cylinderinspector 3D

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Product Description
Optical 3d measuring device based on white-light interferometry
• designed for the control of inner cylinder surfaces for the automotive industry
• Speedytec
o massive parallel data processing on GPU’s
o extreme fast scanning
o real time 3d evaluation
o optimized for steep structures
o integrated data quality parameter for sample optimized filtering processes
• single objectives
o manual exchangeable
o magnifications from 2.5x ... 100x
• push button scan and evaluation macros using smartVIS 3D as system- and MountainsMap as
evaluation software
• simplifies handling
• 360° rotation
• manual insertion axis
• optional motorized insertion axis with automated stitching

Intention of the cylinder inspection
Lapping / structuring of inner cylinder running surfaces:
• structures have an essential influence on the friction:
o the oil retaining volume is essential for the necessary lubrication of the friction partners piston and
cylinder surface
o smooth contact areas reduce the wear and friction special on lower revolution speed
o pores can reduce the oil consumption still providing the necessary oil retaining volume for the
lubrication of the friction partners
o honing structures – angle, furrows... have an big influence of the oil transport and the
hydrodynamic lubrication
• the optimization of the structures can reduce the consumption of engines as well as extend the live time
• there are various positive effects as reduction of the environmental pollution and reduction of the
operation costs – this increase the value of cars and has a significant impact on purchase decisions
Typical operation areas of the Cylinderinspector3D
• research and development
o optimization of production processes
o assessment of functional behavior on basis of the 3d structures without extended tests
o wear evaluation after running tests
• quality control
o survey of production processes
o optimization of tool exchanges ... in the production

Technical Product Specification
smartWLI Cylinderinspector 3D
Cylinder Diameter 70 ... 125 mm (standard configuration)
Measurement Technique White-light interferometry
Height resolution / nm 1 nm (all objectives / field of views)
Scanner Precision piezo drive with gauge control
Scan Range 200 µm
Speed up to 20 µm/s
System Software smartVIS 3D / Speedytec on GPU
Evaluation Software MountainsMap with GBS programmed extensions
Array 1624 x 1234 measuring points
Weight app. 12 ... 14 kg
Power Supply 100 to 240 VAC, 50/60 Hz
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Optional configuration
standard
extended
motorized
Insertion System
manual down to app. 188 mm
manual down to app. 270 mm
automated z axis down to app. 200 mm
Optical Configuration
Magnification 5x 10x 20x 50x
Field of View / mm 2.8 x 2.08 1.4 x 1.04 0.7 x 0.52 0.28 x 0.21
Point Distance / µm 1.6 0.8 0.4 0.16
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Modern technologies require a detailed quality control
Aluminum engine blocks*
monolithic quasi - monolithic heterogenous - liner
coated bores
local material
engineering
dry
cast-in pressed in slip-fit
wet
hypereutectic
Al-Si alloy
galvanic Ni-SiC
dispersion
Al matrix
compound
grey iron
machined
grey iron
plasma coating
AlSi/PM
hypereutectic
AlSi
PVD thin layer
TiN, TiAlN
grey iron as
cast with rough
outer surface
galvanic Ni-SiC
dispersion
grey iron
coated
laser alloying
with Si
plasma spayed
AlSi/PM
There are many competitive technologies used (green) new on
the marked (yellow) or under development (red). All technologies
have several production steps and need a sophisticated and
adapted quality control.
*Source Kolbenschmidt 2011 / Al Automotiv manual
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Evaluation parameters for inner cylinder running surfaces
Honing structures:
• Honing angle
• Honing grooves
o directional classification (rising,
falling, across)
o numbers, depth, area, volume
o Distance between groove
o Cross grooves
Plateaus:
• contact roughness
Functional 2D Parameters
• Rk, Rpk, Rvk
Structure evaluation
Surface Roughness
Cavities / pores:
• numbers / distances
• volume
• area
• depth
• distribution of cavities (according
volume, area and depth)
Marbling:
• % over surrounding surface
Functional 3D Parameters
• Sk, Spk, Svk
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Different surfaces and a wide range of priorities for measurements
Technologies get optimized in the same directions:
• lower friction
• wear resistance
• lower oil consumption
• weight reduction
...but measuring devices are use for different purposes...
R&D:
• detailed analysis for technology optimization
Quality control:
• fast survey of predetermined parameters
• different priorities for the used technology
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Scans with various magnifications
2,5 x Objective
10 x Objective
50 x Objective
more structures per scan – more details from each structure
5 x Objective 20 x Objective 100 x Objective
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Sample: many cavities but not enough details of honing structures
Partial area of a single scan using the 2.5x Objective
FOV: 7.2 x 4.5 mm²
time:

Sample: many detail but only a single (large) groove inside
Single scan using the 50x Objective
FOV: 0.28 x 0.21 mm²
time:

Sample: local variation of cavities, multiple scans necessary
mm
2.0
1.5
1.0
FOV: 7,2 x 4,5 mm²
time:

Recommendation for the correct field of view
Check list to select the correct system configuration:
• min. 10x higher resolution in xyz than the feature which should be measured
• min. 10 evaluation features inside the scanning area
• min. 10 measuring positions for statistical analysis
feature parameter reality* required system parameter
seize depth density xy res. z res. area
cavities area 500 µm² > 1 µm 10 / mm² 1 / mm

Robust form filtering
cylinder surface
filtered surface (z-range reduced)
surface with out marked cavities
robust filtered surface (z-range reduced)
Robust filters (polynomial, gaussian and combinations) are the basis for all following evaluation processes.
“Robust” are filters, which eliminate the influence of cavities and avoid local waves on the filtered surface.
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Structure separation
robust filtered cylinder surface
honing
cavities
marbling
Structure characteristics (directional orientation, depth, height, seize) can be used to separate the
structures from each other and evaluate them separately.
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Honing Structure FFT Analysis
mm
1.0
0.8
0.6
µm
1
0
mm
1.0
0.8
0.6
µm
1
0
-1
-2
0.4
0.2
0.0
0.0 0.5 1.0 mm
-1
-2
-3
0.4
0.2
0.0
0.0 0.5 1.0 mm
-3
-4
-5
-6
Parameters Value Unit
Honing Angle - Honing Structure FFT Analysis 18.20 °
Rising Grooves - Honing Structure FFT Analysis 16.20 °
Falling Grooves - Honing Structure FFT Analysis 20.20 °
Rising Structures - Honing Structure FFT Analysis 26.11 %
Falling Structures - Honing Structure FFT Analysis 34.52 %
Cross Structures - Honing Structure FFT Analysis 2.00 %
Closed Structures - Honing Structure FFT Analysis 37.37 %
Parameters Value Unit
Honing Angle - Honing Structure FFT Analysis 18.05 °
Rising Grooves - Honing Structure FFT Analysis 17.20 °
Falling Grooves - Honing Structure FFT Analysis 18.90 °
Rising Structures - Honing Structure FFT Analysis 8.86 %
Falling Structures - Honing Structure FFT Analysis 14.05 %
Cross Structures - Honing Structure FFT Analysis 4.52 %
Closed Structures - Honing Structure FFT Analysis 72.57 %
Comment:
The GBS programmed Honing Structure FFT Analysis allowed a separate analysis of rising and falling structures. The
sample on the right site shows a higher percentage of closed structures because of the cavities (positive) but also more
cross structures. The scan on the left side shows a more falling structures and on the right side more rising structures.
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Key cavities
1.00 µm
Number of islands 44
Threshold 1.00 µm
Parameters Unit Grain #1 Grain #2 Grain #3 Grain #4 Grain #5 Grain #6 Grain #7 Grain #8 Grain #9 Grain #10 Grain #11 Grain #12 Grain #13
Area mm² 0.0056 0.00515 0.00307 0.00291 0.00235 0.0017 0.00169 0.00159 0.00158 0.0013 0.00113 0.000941 0.000933
Aspect ratio 1.53 1.58 3.41 2.92 2.73 3.83 2.02 2.19 4.03 2.42 2.98 2.67 1.91
Volume µm³ 13995 20813 6088 8015 2807 2576 4531 3282 2414 2432 1116 2045 3372
Max height µm 4.74 9.98 4.00 6.73 2.70 4.67 4.54 3.31 2.89 4.36 2.67 4.29 9.11
Height/Surface ratio µm/mm² 847 1937 1304 2310 1148 2740 2688 2086 1831 3358 2365 4557 9767
Status 0 0 0 0 0 0 0 0 0 0 0 0 0
Separated cavities could be counted and statistically
evaluated.
Many classificatory operator – as depth, volume, form
factors ... can be used to analyze many partial aspects
from the cavities.
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Key aspect “marbling”
photorealistic 3d plot
grey coded 3d plot
Marbling – the camera image shows an texture as could be seen on marble surfaces. The black lines are
cracks in the surface. Inner tensions could cause that surface plateaus standing out of the surrounding
areas.
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Key aspect “marbling”
0.20000 µm
NM
Number of islands 23
Threshold 0.20000 µm
Parameters Stat. Value Unit
Area Mean 0.0014092 mm²
Volume Mean 328.36 µm³
Marbling – areas which are standing up can be detected and evaluated.
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Key 2d parameters
µm
5
0
-5
-10
Context Mean Std dev Min Max
ISO 4287
Amplitude parameters - Roughness profile
Rp µm Robust Gaussian filter, 0.8 m … 0.786 0.328 0.332 1.80
Rv µm Robust Gaussian filter, 0.8 m … 3.07 2.73 0.192 14.5
Rz µm Robust Gaussian filter, 0.8 m … 3.86 2.86 0.773 15.5
Rt µm Robust Gaussian filter, 0.8 m … 5.09 2.96 0.873 16.0
Ra µm Robust Gaussian filter, 0.8 m … 0.318 0.269 0.118 1.65
Rq µm Robust Gaussian filter, 0.8 m … 0.587 0.594 0.146 3.50
ISO 13565
ISO 13565-2
Rk µm Robust Gaussian filter, 0.8 m … 0.489 0.0688 0.344 0.809
Rpk µm Robust Gaussian filter, 0.8 m … 0.280 0.155 0.0951 1.03
Rvk µm Robust Gaussian filter, 0.8 m … 1.81 1.73 0.106 11.3
-15
-20
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 mm
Information
Profile
T-axis
honing with cavities > Mirrored (in Z) > Filtered (Median Denoising 5x5) > Resampled (812 points x 617 line…
Y-axis = -0.549 mm
Parameters Value Unit
Length 1.44 mm
All available lines can be analyzed parallel and statistically classified to increase the significance of results.
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Key 3d parameters
Sk
Spk
Svk
0
1
2
3
0 10 20 30 40 50 60 70 80 90 100 %
10.0
Vmp
%
80.0 % Vvc
Vmc
4
5
6
7
8
9
10
Vvv
0 20 40 60 80 100 %
Sr1
Sr2
Information
Filter settings Unfiltered.
Parameters Value Unit
Sk 0.532 µm
Spk 0.313 µm
Svk 2.10 µm
Sr1 10.2 %
Sr2 88.2 %
Sa1 16049 µm³/mm²
Sa2 123864 µm³/mm²
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12
13
14
15
16
µm
Parameters Value Unit
Vmp 0.0147 ml/m2
Vmc 0.187 ml/m2
Vvc 0.264 ml/m2
Vvv 0.138 ml/m2
Parameters as Spk can be used to evaluate the contact roughness.
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Gehring is using the smartWLI’s to optimize production processes
Gehring today:
• Expert for functional surface optimization
• since 1926 worldwide leader for lapping
technologies
• partner for many automotive companies
• worldwide 9 locations with app. 800 employers
• head quarter in Ostfildern near Stuttgart
Technologies:
Technological motivation
EU 2020
95 g CO 2 /km
fuel consumption
optimized
friction
optimized
functional surfaces
honing machines
honing tools
abrasives
Laser systems
Lapping Thermal spraying Laser structuring
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friction coefficient µ
Structures with high retaining volume and reduced oil consumption
Stribeck-curve
the friction will be reduced and the
minimum achieved on lower speed
(revolution) speed / v
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Surfaces with functional optimized laser structures
Spk: 0.19 µm
bearing shells will be fixed on elevated
laser structures (much higher friction
and nearly 20x larger Spk values)
Spk: 3.52 µm
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Rz / nm
Ra / nm
Proven system accuracy
certificate
Rz: 128.4 (113.0 ... 143.8) nm
Ra: 24.1 (21.4 ... 26.8) nm
measurement results:
Rz: 144.6 nm (std. Rz: 3 nm)
Ra: 24.7 nm (std. Ra: 0.7 nm)
field of view: 1.4 x 1.04 mm²
scan time: < 2 s
point density: 0.8 µm
mode:
high resolution
VSI
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27
26
25
24
23
160
155
repetition
0 5 10 15 20 25 30 35
repetition
150
145
140
0 5 10 15 20 25 30 35
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Advantages of the smartWLI technology
General advantages of the smartWLI Cylinderinspector 3D
• easy handling
• short scanning time
• complete software based on MountainsMap with customized evaluation macros and GBS programmed
functional extensions for the evaluation of honing structures
• insertion depth up to 270 mm
Compared to systems based on confocal measuring technologies
• extreme height resolution of 1 nm for all magnification / objectives
• no reduction of the height resolution for larger scanning areas in single scans
• independent height calculation of direct neighborhood points for improved xy resolution
• without limitations as pinhole density of confocal microscopes
• using of high resolution matrix cameras
Compared to competitive systems with based on similar White-light interferometric technology
• Speedytec use the power of high speed graphic cards or FPGA’s and provides always real time
calculation of the point cloud even for high speed high resolution matrix cameras
• improved algorithms using the high speed image processing of graphic cards or FPGA’s provide a lower
noise and better data quality on geometries with steep slopes and samples with extreme black white
differences
„leading company’s recommend the white light interferometry as preferred method
for cylinder inspections...“
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