Operation Deflection Shapes / ODS
ODS, or Operation Deflection Shapes, belongs to the first approach to vibration measurement, namely vibration diagnostics. It is about making visible the vibrational behavior of the structure under the given operating conditions. Shape means the movement of one point relative to other points. Unlike modal analysis, here we do not know the forces acting on the system. Otherwise, the same technical and software tools are used for data measurement and processing.
The disadvantage is that we do not get the full dynamic model and therefore not even the natural frequencies, modes and damping properties. We cannot even deduce from the measured data what would happen at different frequencies.
They are used to detect:
• How much does the machine move?
• Where and in what direction does it move the most?
• What happens at resonance and what does a given mode look like?
• Where does structure excitation occur?
• How to reduce the vibration level?
The output of the ODS method is an animation of vibrational movement at a certain frequency.
