Patent ID: 7255008

Claim:
A vibration-testing system, comprising: a vibration table ( 4 ) on which a material to be tested is placed to implement a vibration test; horizontal vibration shakers disposed on both sides of the vibration table ( 4 ) in opposite to each other and for vibrating the vibration table ( 4 ); a means ( 70 a ) for moving vertically at least one of the horizontal vibration shakers; a sensor for detecting a rotational mode (M) appearing in the vibration table ( 4 ); and a control means ( 55 ) for moving vertically the at least one horizontal vibration shaker by the vertical moving means ( 70 a ) based on a detection signal of the rotational mode (M) derived from the sensor, whereby a positional difference is produced on a horizontal vibration axis ( 63 ) in the opposed horizontal vibration shakers, and in addition, vibration forces of the horizontal vibration shakers are controlled to suppress the rotational mode (M).