the present invention is embodied in an actuator arm which is mounted to a primary actuator . the primary actuator positions the actuator arm , with a read / write head mounted to the actuator arm , across a data storage disk . the actuator arm comprises an inboard portion , an outboard portion and a pair of bimorph actuators . the inboard portion has a longitudinal axis and is attached to the primary actuator . the outboard portion has the read / write head mounted onto it . the pair of bimorph actuators are deflectable together in a common direction and are connected between the inboard and the outboard portions . upon deflection of the bimorph actuators in the same direction , the outboard portion is translated along an at least nearly straight line transverse to the longitudinal axis of the inboard portion . this transverse motion allows the read / write head to be kept substantially within a plane parallel to the surface of the data storage disk , preventing damage caused by possible contact between slider and the disk surface from rolling the slider due to out - of - plane motions . further , the use of bimorph actuators provide increased displacements of the read / write head . also , since the head displacement is not a function of microactuator &# 39 ; s position along the actuator arm , the actuator arm can be shorter , allowing for use in compact disk drives .