Video extensometer

We use the non-contact video extensometer from the German manufacturer LIMESS to measure the elongation of material samples. This is integrated into our electronics via a serial interface. The non-contact measurement of elongation is not only important for steel or plastics, but also where contact with a specimen is not possible, such as films or paper. The measuring range is not dependent on the sample length and is up to 1000% elongation. Image fields of a few millimeters up to several meters are possible - thus also strain-controlled tests.

Technical description:

Camera RTSSCAM2.4MP

DCMU 2.4 MP, 2.4Megapixel (2000 x 1200 Pixel), 2/3“ Image sensor, USB3

For high measuring accuracy in dynamic tests
Accuracy class 1.0 with 100mm field of view
1µm resolution with 100mm image field width
Longitudinal strain: resolution up to 0.002% strain
Transverse strain over sample cross-section
Measuring rate up to approx. 1500Hz
Scope of delivery: Camera, USB3-cable 5m

Fixed focal length lens

Compact quality lens with fixed focal length.
Standard focal lengths: 12, 25, 35, 50, 75, 80 mm.
Optics are selected according to the application.

The RTSS (Real Time Strain Sensor) video extensometer is a non-contact strain measurement system based on a high-resolution digital camera and real-time image processing. It is mainly used automatically with tensile testing machines. Component deformation is measured with sub-pixel accuracy between two or more line markings. It is also possible to measure the movement of a marker during bending tests and for certification/calibration. The system is used for image fields of approx. 10mm to 2000mm.

Typical applications are the determination of material parameters [E-modulus, transverse contraction coefficient, etc.], strain-controlled tensile tests, crack tracking, cyclic tensile tests, dynamic and high-speed tests, vibration analysis, etc.

The data is transferred to external software and devices via a digital or analog interface. RTSS is 100% compatible with common tensile testing machines such as Instron, MTS, Zwick, Schenk, etc.

Features:

Video extensometer for use on (tensile) testing machines.
Measuring rate typically 100 Hz (optionally up to 4KHz with special camera)
Measurement of
- Longitudinal strain over 2 sample markings.
- Distance of the sample marker (calibration).
- Measurement of transverse strain via sample geometry.
- Constriction over sample cross-section.
- Width of the sample over the sample cross-section (calibration).
Multiple marker detection: For a spatially resolved strain measurement, up to 20 line markers can be detected simultaneously.
Measuring accuracy approx. 0.002% for longitudinal elongation (HR version)
Saving images during the test. The images can be converted into an AVI using RTSS. The strain distribution can be measured using digital image correlation (optional at extra cost).
Available interfaces: Serial, ASCII file, DOLI controller, DLL, Optional: Analog via DAQhw (2 channels, ±10V, 16bit).
A modern, configurable and intuitive user interface
Use of templates for various measurement tasks
The thread-optimized kernel supports multi-core processors for a low processor load
This allows, for example, installation on the control computer of the testing machine
Scope of delivery: Software license, installation CD, online manual and short operating instructions.