Development of a Testing Device for Measuring the Functional Parameters of UAV Recovery Systems

In the context of the increasingly dynamic development of Unmanned Aerial Vehicles (UAVs) and the fields in which they are used, as well as by the increasingly restrictive legislative requirements, there is a need to implement a recovery system in the event of hardware or software malfunctions. This system is necessary in order to limit the damage that can occur to the onboard equipment, as well as to the goods and people on the ground. In addition to the classic electronic fail-safe systems, currently implemented at the software level in most flight algorithms used for autopilots, the last barrier to their recovery is the classic parachute recovery system. Our goal was to test and optimize a classic parachute recovery system having two types of veils, a cruciform one (surface of 2.26 sqm) and a spherical one (surface of 2.75 sqm). Our testing device developed in order to acquire the functional parameters of the recovery systems let us measure: optimal launch speed, minimum opening speed, maximum opening speed, shock at opening, opening time, oscillation after opening. The purpose of the experiments was to reduce the descending speed of a UAV with a mass of 3 kg up to a speed of 5 m/s. All of the functional parameters are necessary in order to choose the optimum wing shape, the folding mode, the need to implement the folding bag, the use of the extractor parachute, as well as determining how the UAV's fuselage elements can interfere with the opening process.