A modal test method of casing was proposed based on scanning laser Doppler vibrometry (SLDV)
and the 3D full-field vibration measurements of thin-wall casing were completed by studying laser Doppler vibrometry (LDV) measurement principle. A 3D laser measurement method for measuring each part of casing independently and a modal splicing technique were established
the data measured by 3D laser was processed and the modal parameters of casing were identified accurately. Modal correlation between SLDV measurement modes and conventional acceleration sensor measurement modes was analyzed. Results showed that normalized cross orthogonality (NCO) values were about 0.9 and the frequencies difference was very small
validating the feasibility and advantage of using the SLDV to measure the 3D full-field vibration of thin-wall casing.