Vibration mapping for NVH testing
This application note demonstrates how Ommatidia’s Q2 multibeam Laser RADAR extends classic laser Doppler vibrometry into dense, full field automotive body vibration mapping. The Q2 simultaneously acquires 65 points across the full structure.
Application overview
Q2 enables non-contact car body vibration analysis for automotive NVH testing. Using multibeam Laser Doppler Vibrometry and Laser RADAR, it measures vibration velocity from 65 simultaneous laser points and scans the vehicle body to create dense vibration maps. Engineers can visualize resonances, transmission paths and operational deflection shapes without accelerometers, cabling or mass loading. The result is faster, cleaner insight into how panels, glazing, trims, tires and structures behave under real conditions.
Application Context
NVH teams need to know where vibration comes from, which components amplify it and how the response changes with frequency. Doors, mirrors, glazing, tires, trims and windscreen bonding can all contribute to cabin noise and perceived quality issues. Contact sensors remain useful, but they add setup time and can disturb lightweight structures. Q2 provides full-field, non-contact vibration measurement linked to vehicle geometry, supporting troubleshooting, design validation and FEM correlation.
How it works
Place Q2 a few meters from the vehicle or component. The system first checks optical return with an intensity scan, then captures 3D geometry with a metrology scan. Vibrometry acquisition follows: 65 points are measured simultaneously while scanning builds a vibration map of the target area. Ommatidia software supports spectrum analysis, peak extraction, waveforms, operational deflection shapes, cross-correlation maps, STFT and HDF5 export for post-processing.
Operational benefits
Q2 reduces NVH test preparation by replacing large accelerometer arrays with optical, multi-point measurement. It avoids mass loading, preserves real boundary conditions and captures spatial vibration patterns that isolated sensors can miss. Engineers can compare frequencies, identify local or global vibration modes, detect weakly constrained areas and validate damping, bonding or trim changes. Geometry-linked vibration data also supports FEM correlation, model validation and faster design decisions.
Proof points
In an automotive test, Q2 measured vibration over 65 simultaneous points at up to 40 kHz. The workflow captured sufficient optical return from dark bodywork and tires, generated 3D geometry, and produced frequency-resolved vibration maps. Results showed global body movement at 28 Hz, localized tire response at 42 Hz, and localized activity around tires, doors and mirrors at 85 Hz. This demonstrates Q2’s value for real-vehicle NVH diagnostics and vibration mapping.
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