Abstract: A toolbar with a longitudinal axis and a machining tool for machining a workpiece, the toolbar comprising at least one accelerometer configured to generate an electric signal proportional to the velocity of the toolbar along a direction; at least one piezoelectric actuator; and a control logic unit, operatively connected to the at least one accelerometer and to the at least one piezoelectric actuator, wherein control logic unit is configured to drive the at least one piezoelectric actuator by a driving signal proportional to the velocity derived from at least one accelerometer adapted to compensate the torque and the vibrations on the toolbar.

Abstract: An apparatus for electrical discharge machining process is disclosed. The apparatus comprises adjustable supports, up-on which an elongated workpiece to be machined can be placed and rotated. The adjustable support allows to adjust the position of the workpiece with respect to a base plate. The apparatus further comprises a rotating member, adapted to grip one end of the elongated workpiece to be machined and rotate it around its longitudinal axis. Also disclosed are a method for machining rotor and a monolithic shaft-impeller rotor.