A flight-path reconstruction algorithm for tethered aircraft, which is based on an extended Kalman filter, is presented. The algorithm is fed by the measurements of a set of onboard and ground-based instruments and provides the optimal estimation of the system state-space trajectory, which includes typical aircraft variables such as position and velocity, as well as an estimation of the aerodynamic force and torque. Therefore, it can be applied to closed-loop control in airborne wind energy systems and it is a first step toward aerodynamic parameter identification of tethered aircraft using flight-test data. The performance of the algorithm is investigated by feeding it with real flight data obtained from a low-cost and highly portable experimental setup with a four-line kite. Several flight tests, which include pullup and lateral-directional steering maneuvers with two kites of different areas, are conducted. The coherence of the estimations provided by the filter, such as the kite state-space trajectory and aerodynamic forces and torques, is analyzed. For some standard variables, such as kite Euler angles and position, the results are also compared with a second independent onboard estimator. ; This work was supported by the Ministerio de Economía, Industria y Competitividad of Spain and the European Regional Development Fund under the project ENE2015-69937-R (MINECO/FEDER, UE). G. Sanchez-Arriaga's work is supported by the Ministerio de Economía, Industria y Competitividad of Spain under grant RYC-2014-15357. R. Schmehl was partially supported by the European Union's projects AWESCO (H2020-ITN-642682) and REACH (H2020- FTIPilot-691173). ; Publicado
Flight-path reconstruction and flight test of four-line power kites
2018-12-01
AR/0000023870
Article (Journal)
Electronic Resource
English
DDC: | 629 |