Optical Communication Terminal For Mobile Robots

Abstract

Optical wireless communication is the promising technology for mobile platforms high-speed data exchange. Technology has already demonstrated applications in different fields and for different platforms: from satellites to trains and unmanned aerial vehicles. The technology has several valuable advantages comparing to existing radio frequency solutions: communication terminal and antenna are smaller; connection is more secured and energy efficient. However, to achieve the mass, power and communication parameters optimal ratio it is required to provide the highly accurate laser beam pointing. This can be achieved using the visual system as a feedback and high-speed control loop. Even though there are several approaches for the laser terminal design for mobile platforms, development of an alternative high-frequency tracking system and its implementation using the visual feedback remains relevant for applications on mobile robotic systems. Current work is dedicated to study a gimbal-based optical terminal and pointing system for mobile robots communication. Based on the previously derived requirements for the optical terminal, a pointing and tracking system architecture is developed. The mathematical model of a two-axes gimbal including the mutual influence of the pointing system drives and platform is derived together with the model of control system. System stability and accuracy are evaluated considering several scenarios and parameters of the optical terminal are discussed.