Displacement measurements using 4DVib
The 4DVib unit is set up facing the structure to be inspected.
The 4DVib unit measures the distance between itself and the inspected structure at very high frequency.
Multiple points of the structure are monitored simultaneously and differentiated automatically based on their distance to the 4DVib unit. Measurements are therefore made without the need to access the structure, and can be made with or without dynamic stress.
Under optimum conditions, measurements are accurate to between 2 and 3 microns. High-frequency movement measurements make it easy to calculate displacement velocities (vibration in the same way as a geophone), and the natural frequency modes of the structure.