VIBRATION ACTUATOR FOR SHEAR WAVE ELASTOGRAPHY, SYSTEM AND METHOD

A vibration actuator (10) for mechanically generating a shear wave comprises a plurality of n rotational vibrators (141, 142, 143), an accelerometer (16), and a controller (18). The plurality of n rotational vibrators enables generation of a vibration vector with desired directional behavior selected from a plurality of vibration vectors (34, 36, 38) of different directional behaviors. Each rotational vibrator comprises an independently controllable motor (20) having a drive shaft (22) and an eccentric disk (24). The accelerometer is arranged to detect a vibration vector generated by at least two of the plurality of n rotational vibrators. The controller selectively controls a first set of two rotational vibrators to rotate respective eccentric disks in a first coordinated manner to produce a first vibration vector, and a second set of two rotational vibrators to rotate respective eccentric disks in a second coordinated manner to produce a second vibration vector, with different respective directional behaviors.