Advanced Video Extensometer
The Advanced Video Extensometer is a non-contact optical strain measurement system designed to deliver accurate, real-time data without clips, arms, or markers touching the specimen. Using Digital Image Correlation (DIC) technology, it tracks surface patterns frame by frame to measure elongation, extension, deflection, and deformation during tensile, compression, and flexural testing. Since there is no physical contact with the specimen, the system can continue measuring strain through fracture, making it well suited for quality control, materials research, and R&D applications alongside a universal testing machine.
Built on the Quantum-3D platform, the video extensometer measures axial and lateral strain simultaneously without additional senso![]()
rs. This provides transverse strain data and enables Poisson's ratio measurement within the same test. Each test is recorded as a sequence of images, allowing engineers to replay test events, change the virtual gauge length, reposition measurement points, and recalculate strain without repeating the test. For many materials, no paint or artificial markers are required because the system can detect natural surface texture, including textured steel surfaces with mill scale.
The Advanced Video Extensometer is suitable for destructive testing as well as applications involving extreme temperatures or hazardous test environments. Its non-contact design allows operators to remain away from the load frame while measurements are captured remotely. With no physical components attached to the specimen, the system helps reduce errors caused by slippage, misalignment, and incorrect gauge-length positioning associated with contact extensometers.
Analog and digital input/output channels provide connectivity with universal testing machines and third-party equipment, supporting synchronized data acquisition and real-time test analysis. With high-resolution optical measurement, DIC-based strain tracking, and flexible post-test analysis, the Advanced Video Extensometer provides a versatile solution for precise material deformation and strain measurement.
Video Extensometer (Advanced) Applications
The Advanced Video Extensometer provides non-contact strain measurement for a wide range of materials, specimen geometries, and demanding test environments. Its optical DIC technology can capture deformation without physically loading or interfering with the specimen, making it suitable for metals, plastics, rubber, composites, reinforcing steel, and advanced materials.
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Metals and Tensile Testing: Measures axial strain, elongation, yield behavior, necking, and elongation at break for metal specimens in accordance with ISO 6892 and ASTM E8/E8M.
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Plastics and Films: Measures deformation and strain in thin, flexible, delicate, and stretchable plastics and films according to ISO 527 and ASTM D638, without adding physical load from a contact gauge.
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Rubber and Elastomers: Tracks the high elongation of rubber and elastomer specimens according to ISO 37 and ASTM D412, maintaining measurement through the complete tensile test and up to fracture.
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Composites and Advanced Materials: Captures full-field strain across stiff, low-strain composite materials in tests such as ASTM D3039, reducing the risk of specimen interference associated with contact extensometers.
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Rebar and Prestressing Strand: Measures strain and total elongation along reinforcing bars and prestressing strands using full-length specimen tracking.
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Round and Flat Specimens: Provides axial and lateral strain measurements for both round-bar and flat specimens, supporting material characterization and qualification testing.
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High-Temperature and Hazardous Testing: Captures strain inside furnaces, environmental chambers, and other challenging test environments while allowing operators to remain at a safe distance from the test area.
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Research and DIC Strain Mapping: Generates 2D and 3D strain maps for advanced materials research, with capabilities for crack-length measurement, bending analysis, torsion evaluation, and detailed deformation analysis.
Standards
The Advanced Video Extensometer supports a broad range of international standards for extensometer calibration, tensile testing, strain measurement, and material characterization. It is suitable for laboratories performing routine and advanced testing across metals, plastics, rubber, and composite materials.
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ISO 9513 – Metallic materials: calibration of extensometer systems used in uniaxial testing, including Class 0.5 extensometer classification.
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ASTM E83 – Standard Practice for Verification and Classification of Extensometer Systems.
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ISO 6892-1 – Metallic materials: tensile testing, Part 1, test method at room temperature.
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ASTM E8/E8M – Standard Test Methods for Tension Testing of Metallic Materials.
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ISO 527-1 – Plastics: determination of tensile properties, Part 1, general principles.
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ASTM D638 – Standard Test Method for Tensile Properties of Plastics.
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ISO 37 – Rubber, vulcanized or thermoplastic: determination of tensile stress-strain properties.
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ASTM D412 – Standard Test Methods for Vulcanized Rubber and Thermoplastic Elastomers in Tension.
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ASTM D3039 – Standard Test Method for Tensile Properties of Polymer Matrix Composite Materials.
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ASTM E111 – Standard Test Method for Young's Modulus, Tangent Modulus, and Chord Modulus.
Video Extensometer (Advanced) Key Features
The Advanced Video Extensometer combines Digital Image Correlation (DIC), non-contact optical measurement, dual-axis strain tracking, and flexible post-test analysis in a single system. It provides reliable strain data while reducing common measurement errors associated with physical extensometers.
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Non-Contact DIC Strain Measurement: Measures strain optically without physical contact with the specimen, helping eliminate slippage, gauge interference, operator influence, and specimen damage during fracture.
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Accurate Elongation at Break: Tracks the specimen throughout the complete test and maintains the virtual gauge length across the fracture area for accurate elongation-at-break measurements.
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Simultaneous Axial and Lateral Strain: Captures axial and transverse strain at the same time, providing data for transverse deformation and Poisson's ratio without requiring additional sensors.
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Natural Surface Tracking: Detects the natural surface texture of many materials, reducing the need for paint, dots, or other artificial markings before testing.
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Replayable and Re-Analyzable Test Data: Records test images for later analysis, allowing users to adjust virtual gauge lengths, reposition measurement points, and recalculate strain without repeating the test.
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Full-Field Strain Analysis: Provides detailed deformation data across the specimen surface, helping identify localized strain, necking, cracks, and other changes during material testing.
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Flexible Material Testing: Suitable for metals, plastics, rubber, composites, films, and other materials where contact measurement may affect test results.
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Versatile Measurement Tools: Supports single-point measurements for displacement, stroke, and bending deflection; two-point measurements for conventional extensometer applications; and full-length specimen tracking. Additional tools support crack-length measurement, torsion, bending, and 2D/3D strain mapping.
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Adjustable Gauge Length and Wide Measurement Range: Provides configurable gauge lengths from 5 mm to less than 250 mm, with a measurement area covering most of the 260 mm field of view for flexible specimen analysis.
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Safe for Demanding Test Environments: Allows operators to remain away from the load frame during destructive testing and can measure strain during extreme-temperature tests when the specimen remains within the camera's visible range.
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Low-Maintenance, Long Service Life: With no physical components that need to be attached to or removed from the specimen, the system reduces wear, maintenance requirements, and calibration-related concerns.
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Analog and Digital I/O Connectivity: Delivers real-time measurement data through analog output, serial communication, or TCP/IP, while accepting third-party signals for synchronized testing and combined data analysis.
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Dual Shortwave Illumination: Provides consistent lighting across the measurement area to support stable surface-pattern detection and reliable DIC tracking throughout the test.
Theory and Method
Digital Image Correlation (DIC) measures strain by tracking changes in a specimen's surface pattern as it deforms. The system captures an initial image as the reference frame, identifies the geometric center of selected surface patterns, and tracks their movement frame by frame as the specimen stretches, compresses, or bends. Each pattern consists of distinguishable points with varying gray levels, allowing the software to identify and follow specific areas much like distinguishing a constellation against the surrounding sky. By comparing subsequent images with the reference image, pixel displacement is converted into calibrated physical displacement and strain.
A high-speed camera combined with dual shortwave illumination captures the specimen at frame rates from 22 Hz to 100 Hz. Calibration establishes the relationship between image pixels and real-world dimensions, allowing the software to calculate accurate deformation measurements. If a tracked pattern moves outside the field of view or its deformation exceeds the defined confidence level, the latest suitable image can become a new reference frame. This helps maintain tracking during large deformation and high-strain tests.
The system can analyze axial and lateral deformation simultaneously, providing transverse strain data and enabling Poisson's ratio calculations from a single test. This dual-axis measurement capability eliminates the need for separate sensors when both longitudinal and transverse strain are required.
Elongation at Break Measurement
For accurate elongation-at-break measurement, the system divides the specimen's parallel length into multiple virtual tracking points rather than relying on two fixed physical gauge marks. During the test, the software identifies areas experiencing the highest strain and determines the likely fracture location. It then positions the virtual gauge length (Le) around the relevant measurement region so that fracture occurs within the measured zone.
This approach allows the video extensometer to continue monitoring deformation through fracture, unlike contact extensometers that may need to be removed before the specimen breaks. The complete test is also saved as image data, allowing engineers to modify the virtual gauge length or measurement location after testing and recalculate strain without running another specimen.
Video Extensometer (Advanced) Technical Specifications
| Parameter |
Specification |
| Model |
Video Extensometer |
| Measurement Method |
Non-contact, Digital Image Correlation (DIC) |
| Field of View (FOV) |
260 mm (vertical range visible to the camera) |
| Accuracy |
Class 0.5 (0.5%) per ISO 9513, at FOV ≤ 260 mm |
| Frame Rate |
22 Hz to 100 Hz (higher on request) |
| Working Distance |
≥ 400 mm (customizable) |
| Gauge Length (Le) |
5 mm ≤ Le < 250 mm |
| Measuring Range |
260 mm – Le |
| Strain Directions |
Axial and lateral, measured simultaneously |
| Included Tools |
Single-point tracking (bending deflection / displacement / stroke); two-point tracking (conventional extensometer); full free-length / parallel-length tracking (locates the break within Le); others on request |
| Lighting |
Dual shortwave lights |
| Communication |
LAN |
| Output |
Analog signal; digital via serial port or TCP/IP |
| Input |
Analog and digital (third-party device signals) |
