Abstract: A flying apparatus is provided that comprises a airfoil (1) with a streamlined profile for generating an aerodynamic lift force vector (L) acting on the flying apparatus when being exposed to an apparent air flow. The flying apparatus also comprises at least three drive units (4, 42; 5, 51; 6, 61) being adapted to generate a resulting thrust force vector acting on the flying apparatus, the thrust force vector being alignable essentially in parallel with the aerodynamic lift force vector (L). For controlling the aerodynamic pitch of the flying apparatus, the flying apparatus comprises at least one control surface (31, 11). Furthermore, the flying apparatus has an aerodynamic neutral point (NP) that lies, along the longitudinal centre axis (10) and in the direction from the leading edge (17) to the trailing edge (18) of the airfoil (1), behind the centre of gravity (CG) of the flying apparatus.
Type:
Grant
Filed:
October 13, 2015
Date of Patent:
May 12, 2020
Assignees:
TwingTec AG, EMPA Eidg. Materialprüfungs- und Forschungsanstalt
Abstract: Conventionally, CdTe solar cells are grown in superstrate configuration where the light enters the photovoltaic device through a transparent substrate. Still, efficiencies of CdTe solar cells grown in substrate configuration have so far been considerably lower than those grown in superstrate configuration. This invention discloses a photovoltaic device (0) in substrate configuration and a process of making thereof with which efficiencies approaching those of superstrate devices can be reproducibly achieved. Furthermore, long term stability is expected to be better than in state of the art devices. This method is advantageous because the growth in substrate configuration offers several advantages like the growth on metal foils and a more precise control of the junction.