XJTUDIC 3D full field deformation and strain measurement system
 

Application Fields
 Material testing(Displacement, Strain, Youngs Modulus, Poisson Ratios)
 Component testing(Displacement, Strain)
  Biomechanics (bone, muscle, blood vessels, etc.)
 Microscope surface and strain measurement
 Fracture mechanics
 FEA validation
 High speed measurement & Vibration analysis
 Failure investigation
 FLC determination

System Features
 3D surface coordinates, 3D surface displacement & surfaces strain
 3D display of measured values
 Applicable to any material
 Fast, easy and accurate calibration
 Flexible measurement range: mm2 to m2
 Strain measuring range: 0.01% up to several 100%
 Flexible and easy to use trigger function
 Frame Rate£º0-12Hz, 24Hz, 480Hz, 960 Hz

Principle of XJTUDIC
XJTUDIC combines stereo vision with digital image correlation. It can measure the 3D coordinates, 3D displacement and surface strain of object by tracking the speckle image of the object surface in the deformation process. XJTUDIC system is portable, fast, high precision and easy to use.

Speckle tracking process

Easy operation
  The system calibration base on photogrammetry is fast, accurate and can adapt to different measurement area. With the lifting frame, one can operate the system easily. Different type of light source can provide well illumination condition. Multi- function control box provides variety of A/D acquisition, D/A out, and camera triggering.
 

Calibration panels for different measuring range

Lifting frame             Control box

Friendly software interface
(1) Supports both 2D and 3D measurement
(2) Flexible camera calibration, and external image series also applicable
(3) Different image acquisition mode
(4) Area of interest, facet size, and step length is adjustable. 
(5) 18 types of deformation and strain measurement results can be obtained.
(6) 3D display of measured results.
(7) Different kinds of post-processing function, including filter, interpolation and so on.
(8) Coordinates transformation function.
(9) Results analysis tools, including section, stage point, point couple, and curving, etc.
(10) Reporting function
(11) Export movie
 

Software interface

Material property testing
XJTUDIC system can provide the characterization of material parameters far into the range of plastic deformation. Its powerful data analysis tools allow the determination of the local and amplitude of maximum strain, which are important functions in material testing.
  

Experiment setup        Stain distribution of steel   

   
Isolines of strain               FLD
 

  
Major strain of aluminum    Isolines of strain

Titanium alloy compress test
The titanium alloy sample is 5mm high and its diameter is 3mm. Universal testing machine is used to compress the sample, and XJTUDIC is used to measure the specimen deformation of the whole process.   

 Application of XJTUDIC in wood mechanics
Experiment content
(1) To get the Youngs modulus and Poissons ratio of wood by compression test
(2) To get the deformation field information of wood in the three points bending test
    

Displacement field  & Ɛx strain field in compression test

Displacement field in three point bending test 

Ɛx strain field in three point bending test

Measured result
Youngs modulus: 14.77GPa
Youngs modulus: 0.7817

Fracture mechanics
XJTUDIC system is also an ideal solution for fracture mechanics investigation. The full-field measurement deliver exact information about local and global strain distribution, crack growth, and can be used for the determination of important fracture mechanics parameters.
  

Fracture growth image

  
Strain distribution in the fracture process

Large measuring volume application
The measuring area of XJTUDIC can vary from several mm2 to several m2. For large measuring area situation, the spray stencil is used to create the point pattern.
    

Spray stencil         Specimen with created point pattern
    

Experiment setup              Measured result

Application of XJTUDIC in civil engineering
The deformation and flow characteristic of sand is a research focus in civil engineering, however can¡¯t be measured easily using traditional method. XJTUDIC which is a non-contacting optical system is ideal for the investigation of sand characteristics.

Technical data

 

Institute of Metal Forming And Die & Mould Technology
Institute of information & Mechatronics Research
School of Mechanical Engineering
Xi'an Jiaotong University,
No.28, Xianning Road ,Xi'an ,Shaanxi province,China,PostCode:710049
TEL£º86-29-82664583,technology ,82669103, 82664366-807
Email: xjtuom@263.net  WEB: www.xjtudic.com