體應變/內應變測量軟件 

VIC-Volume Digital Volume Correlation (DVC) Software

 

由CSI公司推出的全新Vic-Volume™軟件是VIC數(shù)字圖像相關產品線的一個令人興奮的補充。Vic-Volume利用來自X射線或CT掃描儀等斷層掃描設備的體積圖像來測量施加載荷下試件的內部變形。Vic-Volume™分析獲取的圖像，以創(chuàng)建試件內部行為的三維體積位移和應變數(shù)據(jù)。得到的數(shù)據(jù)是變形數(shù)據(jù)的全場等值線圖，可以查看、動畫展示和提取做FEA驗證。

The new Vic-Volume™ software by Correlated Solutions is an exciting addition to the VIC digital image correlation product line. Vic-Volume utilizes volumetric images from X-Rays or CT-Scanners to measure internal deformation of a specimen under an applied load. Vic-Volume analyzes the acquired images to create three-dimensional volumetric displacement and strain data of the specimen’s internal behavior. The resulting data is a full-field contour plot of the deformation data that can be viewed, animated, and extracted for FEA validation.

 

技術背景 Technology Background

 

數(shù)字圖像相關技術（DIC）因其準確性，穩(wěn)健性，多功能性，靈活性和整體易用性而廣泛流行于的科學家，研究人員和工程師之中。 DIC通常使用白光機器視覺數(shù)碼相機來進行二維和三維表面變形和應變測量。 自1998年以來，CSI公司提供了交鑰匙方式的2D和3D DIC系統(tǒng)，并繼續(xù)為其不斷增長的產品線開發(fā)和添加新的*DIC產品。 最近，CSI開發(fā)了新的軟件，利用X射線或CT掃描儀的實用圖像測量施加靜態(tài)載荷下物體的體積變形(內應變)。

Digital Image Correlation (DIC) has found widespread popularity among scientists, researchers and engineers across the globe due to its accuracy, robustness, versatility, flexibility and overall ease of use. DIC is commonly used to measure 2D and 3D surface deformation and strain utilizing white light machine vision digital cameras. Correlated Solutions has offered turn-key 2D and 3D DIC systems since 1998, and continues to develop and add new advanced DIC products to our growing product line. More recently, Correlated Solutions has developed new software that utilities images from X-Rays or CT scanners to measure volumetric deformation of an object under an applied load.

 

測量設置 Setup

 

CT_inspection_line_detector

上圖顯示了在測試過程中如何采集圖像的典型設置。 斷層掃描儀獲取特定深度坐標處的圖像，然后Vic-Volume分析圖像切片以構建由體素組成的3D體積。 各個體素是子卷的構建塊，其中包含體積圖像關聯(lián)數(shù)據(jù)。

The diagram above displays a typical setup of how the images are acquired during a test. The scanner acquires images at specific depth coordinates, and then Vic-Volume analyzes the image slices to construct a 3D volume made up of voxels. The individual voxels are the building blocks for the sub-volume, which contain the volumetric image correlation data.

 

案例 Example 1

 

puck

橡膠圓盤安裝在兩個夾頭之間，并以已知的增量從CT掃描儀獲取一組參考圖像。 然后分析每個“切片”數(shù)據(jù)以計算靜態(tài)體積測量結果。 在圓盤經受壓縮載荷后，CT掃描儀在相同位置再次獲取圖像。 DIC算法用于計算構成3D體積的每個單獨體素處的體積變化或變形。

A rubber puck is mounted between two grips, and a set of reference images are acquired from a CT scanner at know increments. Each ‘slice’ of data is then analyzed to compute a static volume measurement. After the puck undergoes a compression load, images are acquired again by the CT scanner at the same locations. Digital Image Correlation algorithms are used to calculate the volumetric change or deformation at each individual voxel, which make up the 3D volume.

 

上面的動畫顯示了受壓縮的橡膠圓盤的內部應變（Ezz）。 可以將體積應變(內應變)數(shù)據(jù)作為體積或單個數(shù)據(jù)切片進行查看，分析或提取。 通過該技術，內部壓縮應變可以清楚地看到。

The above  animation displays the internal strain (Ezz) of a rubber puck undergoing compression.  The volumetric strain data can be viewed, analyzed, or extracted as a volume or as individual data slices. The internal compressive strain can clearly be seen.

 

案例 Example 2

RMC-pic

將增強的橡膠基質復合材料安裝在兩個手柄之間，并以已知增量的從CT掃描儀獲取一組圖像做參考。 然后分析每個“切片”數(shù)據(jù)以計算靜態(tài)體積測量結果。 在標本經受拉伸載荷后，通過CT掃描儀在相同位置再次獲取圖像。 數(shù)字圖像相關算法用于計算構成3D體積的每個單獨體素處的體積變化或變形。

A reinforced rubber matrix composite is mounted between two grips, and a set of reference images are acquired from a CT scanner at know increments.  Each ‘slice’ of data is then analyzed to compute a static volume measurement.  After the specimen undergoes a tensile load, images are acquired again by the CT scanner at the same locations.  Digital Image Correlation algorithms are used to calculate the volumetric change or deformation at each individual voxel, which make up the 3D volume.

 

上述動畫顯示了經受張力的增強橡膠基質復合材料的內部應變（Ezz）。 可以將體積應變(內應變)數(shù)據(jù)作為體積或單個數(shù)據(jù)切片進行查看，分析或提取。 如視頻所示，內部張力應變可以清楚地看到。

The above  animation displays the internal strain (Ezz) of a reinforced rubber matrix composite undergoing tension.  The volumetric strain data can be viewed, analyzed, or extracted as a volume or as individual data slices. The internal tension strain can clearly be seen.

 

技術特性 Vic-Volume Software Features

• 通過“Tweening”方法可方便的進行AOI選擇
• 半自動化的初始預測計算
• 針對準確性進行了優(yōu)化，可減少非線性優(yōu)化以減少偏差和插值偽影
• 高度*的內存管理允許分析巨大的體積數(shù)據(jù)集并提高計算效率
• 基于體積3D位移和應變信息

• Convenient AOI selection method through “Tweening’’
• Semi-automatic initial guess computation
• Optimized for accuracy reduce non-linear optimization to reduce bias and interpolation artifacts
• Highly Advanced memory management permits analysis of huge volumetric data sets
• Volumetric 3D displacements & strains