Use of Non Contact Radar Techniques to Dynamic Measurement Purposes

The use of radar techniques to perform static (slowly moving) structural measurements is a well known task and most radar systems are limited to this kind of measurements. Recent progresses in this kind of techniques, however, have encouraged researchers to study and develop radar systems capable to perform dynamic measurements. The main advantage consists in the fact that this kind of system is a non-contact one. However, several problems may be encountered when using such a system to perform dynamic measurements. The aim of this work is to provide the validation of the prototype of a radar system (GBInSAR) developed by LiSALab, underlining the advantages and limitations in the use of this technique to perform dynamic measurements. The previous version of this system was usable to investigate phenomena with slow dynamics. The new system was tested imposing harmonic movements to a trihedron and measuring the displacements with the radar and with a set of accelerometers. Frequencies up to 20 Hz and displacements up to 10+10 mm were imposed during the tests. The tests were performed using one (shifting) reflecting body and nothing else in the scene and with the shifting reflecting body plus other three static reflecting bodies. A comparison between the results obtained with the two measurement techniques is proposed.