VIS - Telesensor

The VIS - Speckle tracking Infrasonic Vibrometer - is an instrument for remote measurement of vibrations that characterize the behaviour of structures subjected to dynamic loads.

With a laser emission around 5 mW the device is able to detect target vibrations induced by micro-seismicity, wind, traffic and other human activities.

Unlike other “in situ” sensors, it can be positioned up to 100 meters from the surface to be monitored and does not need to be positioned perpendicular to the target surface, ensuring accurate measurements even in areas that are difficult to access.

Patents

SpacEarth Technology holds the rights to intellectual property and commercial exploitation:

1. Vibration remote sensor based on speckles tracking, which uses an optical-inertial accelerometer and method for correcting the vibrational noise of such a sensor. March 2020(E. Giacomozzi, S. Bianchi, C. Bianchi, V. Romano, A. Tertulliani)
2. Speckle tracking vibration sensor with dual optical receiver and method of correcting the vibrational noise of such a telesensor. August 2023 (S. Bianchi, E. Giacomozzi) 
3. Speckle tracking vibrometer. August 2025 (C. Bianchi, A. Fiorini) 
4. Speckle tracking vibrometer with low light emission power 2025. August 2025 (C. Bianchi, A. Fiorini)

Operating Principle

The main feature that distinguishes VIS from other optical vibration sensors is that it is based on the reception of light scattered from the target surface. When coherent laser light illuminates a rough surface, a random diffraction image is produced, known as a speckle pattern, which is extremely sensitive to microscopic details on the reflecting surface.

Vibrations in the structure change the inclination of the illuminated surface and, consequently, the speckle pattern. The received scattered light beam is adjusted and projected onto optical sensors in order to detect the target spatial shifts, obtaining a description of the frequency vibrational regime.

Technical Specifications

The VIS is a compact, lightweight instrument comprising a laser, an optical system consisting of a distance-adjustable lens and lenses capable of modifying the received light beam, and two optical sensors connected to a minicomputer for acquiring and processing data for vibration analysis. Data transfer to and from the VIS can be done wirelessly through VNC protocol.

See the extraordinary sensitivity of the VIS in action on YouTube

VIS – Speckle tracking Infrasonic Vibrometer YouTube

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