extensometre optique
TRANSCRIPT
Preliminary Information on our New
Vision Extensometer System (ME 46-450)
5.11.2002
Highlights:
• 30% more Pixels to be processed ( = higher accuracy)
• Ease of Multi Sensor Option. Up to four Images of different Cameras can be processed simultaneously at rates between 20Hz- 100Hz on each pattern; Up to 32 Cameras in less time-critical applications (e.g.: Creep-Test)
• Automatic Start programmable (for automatic handling-
systems)
• User-warnings on improper inclination, contrast, focusing etc
• Parameter settings can be called up by application software
of testing machine
• Zoom-function available on both line spectrum (Gray levels) and image of targets
• Up to 11 axis programmable for axial strain ( strain
distribution)
• Independent cursor-function available for both measuring-lines and Gray-level reference
• Display settings and parameters selected accessible even
during test
• Random positioning of lateral strain axis
• Choice of operating system (WIN 2000, NT, XP)
• Choice of dialogue language (English and German standard supply, other languages might filed by user )
• VGA section independent from grabber section
• Reduced price
Be careful with upgrading existing Video extensometers:
• Hardware basis requirements: minimum 1,7 GHz CPU-frequency
• WIN 2000 minimum
• Upgrade must be done in our factory
FIG. 1a TWIN-CAMERA-SOLUTION FOR DIAMETRIC MEASUREMENT TO COMPENSATE OUT-OF-PLANE MOVEMENT. Option EM 55 required.
Dot Matrix (Two-dimensional Deformation)
Bending Tension
Compression COD
FIG. 1 b MONITOR VIEW OF DIAMETRIC –TWIN CAMERA SOLUTION- AXIAL STRAIN MEASUREMENT IN TENSILE TEST. Simultaneous processing of rear and front specimen view.
Equipment requirements: EM 40 ME 46-450 with Options EM 55 and EM 45
FIG. 2a FINE and COARSE STRAIN-MEASUREMENT. TWIN-CAMERA-SOLUTION (Including automatic -bumbles- Transfer). Recommended for High Extensions (>100 % Le, e.g.: Rubber testing) Equipment requirements: EM 40 ME 46-450 with option EM 55.
FIG. 2b Fine Strain-Measurement on long specimens (Twin Camera Solution). Recommended for high Initial Gauge length (>200 mm) At low tenacity ( e.g.: Testing of Steel cables or Wires) Equipment requirements: EM 40 –ME 46-450 With Option EM 55
FIG. 2c AXIAL AND LATERAL FINE STRAIN-MEASUREMT (TWIN CAMERA SOLUTION). Recommended for High precision R-Value or Poisson’s-Ratio Determination. Equipment requirements: EM 40 ME 46-450 with EM 02 and EM 55.
FIG. 3a COMPRESSIVE STRAIN-MEMEASUREMENT FROM THREE DIRECTIONS. THREE-CAMERA-SOLUTION . Two Options EM 55 required.
.
FIG. 3b ELLIPTIC NECKING MEASUREMENT (Including calculation of a and b). THREE-CAMERA-SOLUTION . Two Options EM 55 required.
FIG. 4 FFT-PROCESSING . Example shown : Total Strain and Strain distribution measurement on Rebars. No marking required. Automatic Symmetry on A5-Region. Options required: EM 60 and –eventually- EM 55 (Second Camera suggested for observed Length lc > 200 mm). Options required: EM 60 and –eventually- EM 55 (Second Camera suggested for observed Length lc > 200 mm).
FIG. 5 LASER SPECKLE EXTENSOMETER EM 71. NO TARGETS REQUIRED. Third and Fourth Camera ( 2x EM 55 ) optional for diametric Strain-Measurement.
FIG 6a HYBRID SETUPS: LASER SPECKLE COMBINED WITH VIDEO. Axial Strain measurement by LASER SPECKLE ( Two Cameras) and lateral Strain / Necking by VIDEO (Third Camera). Equipment-requirements: EM 72+ EM 55 + EM 02
FIG 6b MULTI TASK OPERATING. Simultaneous Processing of coherent – and incoherent –Light Images. Example shown: R-Value Measurement of Steel sheets. Two Cameras employed for axial Strain measurement (Laser-Speckle, Specimen not marked), third Camera for lateral Strain (Video-Profile-Scanning including Necking measurement)
Configuration required: EM 71 , EM 55 and EM 2.
FIG. 7 : SURFACE MIRROR OPTION EM 31-3 (To maintain proper camera distance)
FIG. A1: Single Frame (Camera) processing
FIG. A2: Line Spectrum ( White Light )
FIG. A3: Zoomed Section in Line spectrum
FIG. A 4: Section zoomed to Pixel-Size
NG: Field of View vs. Distance to Object (Valid for Standard 1/3" Camera in ME 46-450 Parameter: FOCAL LENGTH
0
1.000
2.000
3.000
4.000
5.000
6.000
0 100 200 300 400 500
F ield o f View (F OV) [mm]
Dis
tanc
e to
Obj
ect [
mm
]
8 mm
12,5 mm
16 mm
50 mm (standar d)
75 mm
105 mm150 mm
25 mm
FIG. A5: Selection of proper Objective