Design and Application of Pan and Tilt Servo Gimbals in Pointing, Acquisition, and Tracking

Abstract

Directional wireless communications systems are fast becoming an essential part of the world's broadband network infrastructure. When using these types of transceivers in reconfigurable networks, it becomes necessary to point them rapidly and accurately to different locations, or even to targets that may be in motion. The most efficient way of doing this is through the use of two-axis pan and tilt motion stages, also known as gimbals. This paper presents the motivation for, design and construction of, and testing of a pair of multipurpose servo gimbals, usable for both RF and laser transceivers. The gimbals are tested in terms of pointing error, movement speed, and response time. For the network portion, relink times as a function of angular rotation are examined, as well as the angular offset vs. data rate. The gimbal is also tested as part of a remote surveillance network, evaluating its ability to track moving objects.