Optimal Piezoelectric Actuators and Sensors Configuration for Vibration Suppression of Aircraft Framework Using Particle Swarm Algorithm

Table 4

The first 4 order natural modal frequencies.

The order of vibration modal	1	2	3	4
Frequency (not attaching piezoelectric sheets)/Hz	19.58	33.20	48.87	61.75
Frequency (attaching piezoelectric sheets)/Hz	20.70	34.35	49.70	62.50