Abstract: An apparatus for retaining the attitude of a platform on an articulated boom is provided. The apparatus includes master-slave piston cylinders for adjusting the attitude of the platform relative to a reference object. The apparatus further includes a pivot plate defining a triangle having first, second, and third mounting locations with a platform being pivotally mounted to the pivot plates at one mounting location. A piston cylinder is pivotally connected to the pivot plates at a second mounting location and is operatably connected to the platform. A pivot means is pivotally connected to the pivot plate at the third mounting location and, at its other end, is connected to the fixed support about which the articulating boom rotates. Rotation of the articulating boom results in the pivot means pivoting the pivot plate in such a way that the platform is maintained at its preset orientation.