The Major Strain is shown in this result, along with the section as shown, with greater strain at the thicker base of the specimen

An advanced full-field imaging method using 3D image correlation photogrammetry is being used for measuring the tremendous variations in real biological mechanical systems such as bones, tendons, ligaments, and even tissues such as blood vessels. This measurement method has far greater dynamic range than other full-field imaging technologies, making these measurements possible. In addition, 3D image correlation technology is simpler to use and less expensive to implement. It is also inherently three-dimensional, measuring total deformation of complex objects including their shape, rather than just relative deformation.

The dynamic range of the 3D image correlation technology allows the operator to measure the event that is occurring, rather than modifying the event to meet the requirements of the measurement method. This is critical for sensitive and typically unpredictable biological systems. The events can be in microns to millimeters of deformation, static or dynamic, with no requirement for sub-micron stability. Furthermore, the use of stroboscopic illumination enables dynamic response measurements beyond the capability of pulsed ESPI systems.

These results demonstrated the ability of Aramis to measure the strain on a small 3D specimen undergoing high strain under tensile load. The tendon was half attached to muscle (bottom) the other to bone (top), which provided a wide variety of strains in one field-of-view. It was found that for the applied load, the muscle strained to 12%, while the tendon strained to about 2%. For the full report, follow the link below.

Access Optical Deformation and Strain Measurements in Biomechanics