ELIMINATING KEYHOLE PROBLEMS IN AN X-Y GIMBAL ASSEMBLY

摘要

The present invention provides two approaches for eliminating a keyhole problem associated with a directive payload mounted on an X-Y gimbal system (10) which occurs when the payload (55) is required to be pointed at a direction which is close to co-linear to the gimbal s Y axis (25). One embodiment provides for a limited rotation around the Z axis (36) of both the X and Y gimbals as the target (60) approaches a predetermined proximity to co-linearity with the Y axis. Another embodiment provides for a predetermined tilting of the gimbals on the Y axis. Both inventive embodiments provide uninterrupted tracking of a target without expensive slip-rings and rotary joints.