Vibration deflection shape (VDS)

• Uses LDV & PSV software
• Visual interpretation of vibration pattern
• Damage detected in terms of geometric features
• Exact response of the structure is used so accurate
• Good near natural frequency
• Peak point of VDS indicates damage
• Distortion in VDS at damage site

Issues related to VDS

• Correct location of damage not possible
• Easy to obtain data
• In low frequency VDS exact location of damage cannot be predicted
• In high frequency VDs small damage can be located
• Change in excitation point help in damage detection