Flight Testing of a Fully Adaptive Algorithm for Autonomous Fixed Wing Aircrafts Landing

Abstract

This paper presents the flight test results of a fully adaptive algorithm for autonomous fixed wing aircrafts landing developed by CIRA, the Italian Aerospace Research Centre. The algorithm is designed and implemented in the framework of a complete autonomous guidance system, worked out by CIRA, able to allow autonomous way-points navigation, autonomous landing and autonomous collision avoidance for fixed wing aircrafts. The algorithm presented in the paper is designed to perform a fully adaptive autonomous landing starting from any point of the three dimensional space, based on the use of the DGPS/AHRS technology. Main features of the autolanding system based on the implementation of the proposed algorithm are: on line landing trajectory re-planning, fully autonomy from pilot inputs, weakly instrumented landing runway, ability to land starting from any point in the space and autonomous management of failures and/or adverse atmospheric conditions. The flight tests have been conducted at an airfield in Caserta, in the south of Italy, close the CIRA. The paper is structured into several paragraphs describing the algorithm designed for the autolanding maneuver, the control system architecture and the methodologies developed in order to safely manage the possible presence of failures and/or unfavorable weather conditions, the preliminary results of the real time validation with hardware in the loop simulation and, finally, the performances achieved by using the CIRA experimental flying platform, with reference to the real flight experiments. Nomenclature X = position along X-Runway axis ) ( X V X = inertial velocity profile along X-Runway axis ) ( X V Z = inertial velocity profile along Z-Runway axis ) ( X H = position profile along Z-Runway axis 0 H = initial position along Z-Runway axis 0 X = initial position along X-Runway axis 0 X V = initial inertial velocity profile along X-Runway axis F H = desired final position along Z-Runway axis F X = desired final position along X-Runway axis XF V = desired final inertial velocity profile along X-Runway axis ZF V = desired final inertial velocity profile along Z-Runway axis

Adaptive Algorithm for Fixed Wing UAV Autolanding on Aircraft Carrier

“…Alignment and Pre-Touch Down phases are identical to the ones descripted in the previous work already cited 10 , so their description is here omitted for the sake of brevity (nevertheless, some information about the Alignment phase has been provided in the previous section II), while the approach and flare phases have been modified to enable an autolanding on a carrier.…”

“…The trajectory structure, involving the phases of ramp and flare, adopted as nominal case is shown in Figure 3. The nominal trajectory is elaborated during the phases preceding the ramp and the formal equations utilized for the trajectory are similar to that already formulated in a previous work 10 .…”

“…This algorithm, successfully tested by means of several both real time hardware in the loop simulations 8 and flight tests 9 , had still the limitation that the trajectory was generated only once, remaining the same until the touch down without adaptive features. In order to overcome this limitation and to make safer the system, CIRA developed also a fully adaptive autonomous landing algorithm 10 algorithm proposed in the cited work 10 were: on line landing trajectory real time re-planning, full autonomy from pilot's inputs, ability to use weakly instrumented landing runway, ability to land starting from any point in space and autonomous management of failures and/or adverse atmospheric conditions.…”

Evolution of the Tactical Separation System to support the Integrated Mission Management System in the COAST project

“…The possibility to have relevant results in the near term was allowed by the extensive knowledge already gained by the COAST partners, thanks to their background. The TSS, in particular, has been designed by CIRA, whose background already included extensive knowledge in the field of RPAS (Remotely Piloted Aircraft Systems), having CIRA successfully performed several research and development activities about methodologies and technologies for: automatic landing [2], Self-Separation ([3]- [8]) and Collision Avoidance ([6]- [11]), ADS-B (Automatic Dependent Surveillance -Broadcast) exploitation ([6]- [8], [12]- [13]), and automatic trajectory generation ([14]- [16]). Based on such background, CIRA developed in COAST the TSS, reaching the TRL 6 in 2021, based on the successful results of the dedicated flight test campaign.…”

Enabling SAT single pilot operations: tactical separation system design advancements in the COAST project

“…Each one of the consortium partners gathered specific competences and excellent cooperation skills. For what concerns CIRA, the relevant background included automatic landing systems, especially for RPAS (Di Vito et al , 2007; De Lellis et al , 2012), self-separation (Filippone et al , 2015; Di Vito and Torrano, 2021a) and collision avoidance systems (Di Vito and Torrano, 2020; Fasano et al , 2016), ADS-B applications (Di Vito and Torrano, 2020; Di Vito and Torrano, 2021b, 2021a; Orefice et al , 2014, 2015a), automatic trajectory generation (Platts et al , 2007; Di Vito et al , 2009).…”