Development and Experiment of Elastic-rope Launcher for Small Fixed-wing UAVs

Small and medium-sized fixed-wing UAVs have a lower cost compared to large UAVs. Small and medium-sized tactical UAVs have become increasingly prominent, according to the development of intelligence and miniaturization of sensors and weapons, and the new tactics application including teams, swarm, and loyalty wingmen, which is based on artificial intelligence and network communications. Short-range reliable take-off technology is a major problem for small and medium-sized fixed-wing UAVs to achieve all-terrain applications on vehicle-borne and ship-borne. Elastic-rope launcher is available for small and medium sized fixed wing UAVs, with the advantages of brief structure, convenient operation and strong adaptability to environment. This article systematically reviews the development and characteristics of catapult-based UAV take-off technology. The design method of the elastic-rope launcher method is present, including the catapult distance estimation based on the maximum overload constraints and takeoff speed requirement, determination of the initial length of elastic rope according to the launcher geometric configuration and deformation ratio constrains, and the parameters calculation with energy conservation principle. An example UAV launcher is designed and experimental verification is taken. Work in this paper could be in favor of the development of short-range take-off technology for small and medium-sized UAV.