Modal Analysis of Honda Civic Chassis

Vehicles go through a lot of stress and vibrations during day to day use. Any vehicle’s frame should be able to take these without deforming and should retain the structural integrity of the vehicle. This project involved performing a modal analysis on a Honda civic body using shaker test to find the first bending, first torsion mode shapes and modes.


Nine triaxial accelerometers were mounted on the BIW to measure the acceleration in X, Y and Z direction. Accelerometers were mounted at each measurement location. An electro-dynamic shaker with a load cell (force sensor) was attached to the left front at the interface of the BIW.


Data from the DAC was processed using Siemens TestLab. The mode shapes for the first bending, torsion were identified. Polymax estimation algorithm was used to identify the first 5 modes and a stabilization diagram generated was analyzed to check the accuracy of selection.