US 12,189,402 B2
Method and control unit for controlling an overdetermined system, system and aircraft
Burak Yüksel, Mannheim (DE); and Johannes Stephan, Stuttgart (DE)
Assigned to Volocopter GmbH, Bruchsal (DE)
Filed by Volocopter GmbH, Bruchsal (DE)
Filed on Apr. 26, 2022, as Appl. No. 17/729,089.
Claims priority of application No. 102021111104.8 (DE), filed on Apr. 29, 2021.
Prior Publication US 2022/0374028 A1, Nov. 24, 2022
Int. Cl. G05D 1/08 (2006.01); B64C 27/08 (2023.01); B64D 31/06 (2006.01); G05D 1/00 (2006.01)
CPC G05D 1/0825 (2013.01) [B64C 27/08 (2013.01); B64D 31/06 (2013.01); G05D 1/0808 (2013.01); G05D 1/0858 (2013.01); G05D 1/101 (2013.01)] 21 Claims
OG exemplary drawing
 
1. A method for controlling a system, which is overdetermined, with multiple power-restricted actuators, wherein the actuators perform at least one primary task and a number of non-primary tasks, the method comprising:
a) determining a pseudo-control command up∈custom characterp′ based on a physical model of a system, said pseudo-control command represents the torques (L, M, N) and a total thrust force (F) acting on the system,
b) determining a control matrix D, D∈custom characterp′×k according to up=Du, wherein u denotes actuator control commands,
c) dissociating the control matrix D into sub control matrices Di according to

OG Complex Work Unit Math
 q≤p′, so that

OG Complex Work Unit Math
 and up,i=Diu,
wherein the sub control matrices Di and corresponding sub pseudo-control commands up,i for i=1 correspond to the primary task and for i>1 correspond to the at least one non-primary task and wherein a priority of the non-primary tasks decreases with increasing index i,
d) determining actuator control commands for solving the primary task according to u1=D1#up,1, where #denotes a matrix inversion and u1∈custom characterk comprises said actuator control commands which solve the primary task, with u1∈U:={u∈custom characterk|umin≤u≤umax}
e) projecting the non-primary tasks, i>1, into a null space of the primary task, i=1, and into respective null space of all of the non-primary tasks of higher priority, if present, so that Diuj=0, with uj∈custom characterk, j>i, comprises actuator control commands for performing a non-primary task, and
f) providing the actuator control commands from d) and e) at the actuators.