High-performance two-axis gimbal system for free space laser communications onboard unmanned aircraft systems

Michael Locke; Mariusz Czarnomski; Ashraf Qadir; Brock Setness; Nicolai Baer; Jennifer Meyer; William H. Semke

doi:10.1117/12.873938

1 March 2011 High-performance two-axis gimbal system for free space laser communications onboard unmanned aircraft systems

Michael Locke, Mariusz Czarnomski, Ashraf Qadir, Brock Setness, Nicolai Baer, Jennifer Meyer, William H. Semke

Author Affiliations +

Proceedings Volume 7923, Free-Space Laser Communication Technologies XXIII; 79230M (2011) https://doi.org/10.1117/12.873938
Event: SPIE LASE, 2011, San Francisco, California, United States

Abstract

A custom designed and manufactured gimbal with a wide field-of-view and fast response time is developed. This enhanced custom design is a 24 volt system with integrated motor controllers and drivers which offers a full 180o fieldof- view in both azimuth and elevation; this provides a more continuous tracking capability as well as increased velocities of up to 479° per second. The addition of active high-frequency vibration control, to complement the passive vibration isolation system, is also in development. The ultimate goal of this research is to achieve affordable, reliable, and secure air-to-air laser communications between two separate remotely piloted aircraft. As a proof-of-concept, the practical implementation of an air-to-ground laserbased video communications payload system flown by a small Unmanned Aerial Vehicle (UAV) will be demonstrated. A numerical tracking algorithm has been written, tested, and used to aim the airborne laser transmitter at a stationary ground-based receiver with known GPS coordinates; however, further refinement of the tracking capabilities is dependent on an improved gimbal design for precision pointing of the airborne laser transmitter. The current gimbal pointing system is a two-axis, commercial-off-the-shelf component, which is limited in both range and velocity. The current design is capable of 360o of pan and 78o of tilt at a velocity of 60o per second. The control algorithm used for aiming the gimbal is executed on a PC-104 format embedded computer onboard the payload to accurately track a stationary ground-based receiver. This algorithm autonomously calculates a line-of-sight vector in real-time by using the UAV autopilot's Differential Global Positioning System (DGPS) which provides latitude, longitude, and altitude and Inertial Measurement Unit (IMU) which provides the roll, pitch, and yaw data, along with the known Global Positioning System (GPS) location of the ground-based photodiode array receiver.

Citation Download Citation

Michael Locke, Mariusz Czarnomski, Ashraf Qadir, Brock Setness, Nicolai Baer, Jennifer Meyer, and William H. Semke "High-performance two-axis gimbal system for free space laser communications onboard unmanned aircraft systems", Proc. SPIE 7923, Free-Space Laser Communication Technologies XXIII, 79230M (1 March 2011); https://doi.org/10.1117/12.873938

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available