TUAV Location Algorithm Based on SINS Data and Airborne Radar Data

For effective use of tethered unmanned aerial vehicles (TUAVs), on-board controls are required to stabilize their position in space. For extended autonomy, SINS (Strap down Inertial Navigation System) data on the TUAV's spatial position must be corrected by “tech-vision” systems. Except at night and in poor visibility conditions, the 4-meter optical-electronic (OE) and infrared (IR) sensor suites used in the vertical takeoff and landing UAV significantly limit the TUAV's operating time at altitudes up to 300 meters. The proposed replacement of the OE/IR sensor data with data from a MIMO-based on-board radar on the position of a radio-contrasting object (reference point) not only eliminates time constraints on the TUAV's operation, but also significantly reduces computational costs, since the radar data is in binary form. The evaluation of the accuracy of the TUAV position data obtained on the basis of the developed algorithm for the specific case of 100 m cable length and 5 degree angular error showed that the largest errors (up to 8 m) in the determination of the TUAV orientation were observed in the horizontal plane for all considered sensor types. Vertically, the largest errors (3 m) occur when SINS angles are inaccurate. Radar generated data can cause errors of approximately 1.2 m vertically.