TWO AXIS MOUNT POINTING APPARATUS

摘要

The invention is directed toward a pointing apparatus for use in a target tracking system wherein a device (1) is continually pointed in the direction of a target in order to track the target. The pointing apparatus is mountable on a moving body in order to implement a tracking system on a moving body. The tracking system has at least one sensor that generates a signal indicating the orientation of the moving body relative to the target. The pointing apparatus includes a base mounted on the moving body, a pointing arm (2) for carrying the device and a universal joint supported by the base. The pointing arm is rotatably mounted within the universal joint for rotation about first and second control axes, the universal joint being constructed and arranged so as to enable rotation of the pointing arm through greater than 180 degrees but less than 360 degrees about each of the first and second control axes while suffering no singularities of control. The universal joint is further constructed and arranged so that the orientation of the first control axis varies as the pointing arm is rotated about the second control axis, and so that the orientation of the second control axis varies as the pointing arm is rotated about the first control axis. The pointing apparatus further includes a control means, responsive to the at least one sensor, for rotating the pointing arm about the first and second control axes when moving body changes its orientation relative to the target so that the device is continuously pointed in the direction of the target.