Development of Multitarget Acquisition, Pointing, and Tracking System for Airborne Laser Communication

Cluster unmanned aerial vehicles (UAVs) are widely demanded. To achieve high rate and large capacity communication with cluster UAVs, one of the key but still challenge task is to perform multitarget acquisition, pointing, and tracking (APT) under complex airborne environment. To solve this problem, this paper gives one composite axis APT system for multitarget laser communication with cluster UAVs. The APT system consists of a gimbal mirror and piezoelectric fast steering mirrors (FSMs), which can achieve independent and synchronous control of multiple optical axes. The cascade control scheme is designed for the gimbal mirror and the H$\infty$ controller is designed for the FSM. To further improve the control accuracy, the hysteresis compensator based on least square support vector machines (LS-SVM) is proposed. The pruning error minimization method of LS-SVM is applied to reduce the computational cost. The simulation studies validate the control performance of the multitarget APT system. Finally, the experimental prototype is developed. The experimental results further validate the effectiveness of the proposed multitarget APT system.