Abstract: A remote valve positioning apparatus is provided in which a valve spool is resiliently loaded at each end to a normal position, hydraulic fluid is delivered selectively to one end or the other of the valve spool at a fixed flow and the valve is positioned by pressure drop caused by the fixed flow over an orifice proportional to the stroke of the valve spool.

Abstract: A two-axis positioning servoactuator includes a support, a movable member arranged adjacent the support for independent pivotal movement relative thereto about each of two perpendicular intersecting axes, a pair of differential piston and cylinder actuators operatively interposed between the support and movable member for effecting such angular movement about each of the axes, an electrohydraulic servovalve for each of the actuators and operatively associated therewith to control the same, and means providing a position feedback signal to the corresponding servovalve for effecting controlled movement of the member about each of the axes.