SYNERGETIC SYNTHESIS OF A DISTURBANCE OBSERVER FOR THE “FLYING PLATFORM” CONTROL SYSTEM

Abstract

The work is devoted to the synergetic synthesis of the harmonic disturbance asymptotic observer
for the aircraft hierarchical control system. The paper contains the general description of “flying platform”
type vertical take-off & landing aircraft & an asymptotic observer of external disturbing influences
(for example, wind) that have a harmonic dynamics & cause periodic changes in flight height, as
well as in pitch & roll angles. An asymptotic observer must ensure the asymptotic stability of a reserved
system, the implementation of technological invariants, the estimation of unobservable external influences
from the current values of the observed state-space variables, & the absorption of harmonic wind
disturbances. The article also presents an extended mathematical model of the “flying platform” in the
vertical movement mode under external harmonic disturbing influences, including a mathematical description
of the disturbance dynamics, & the upper hierarchy level control algorithms based on the
given technological invariants are synthesized. In addition, the equations of the disturbing influences
asymptotic observer are calculated, which supplement the mathematical model of the “flying platform”
under disturbed motion, & the equations for asymptotic estimates of unobserved variables are calculated,
which are further included in the upper hierarchy level control laws. The possibility of the disturbance
observer synthesis was verified using the observability criterion. Finally, the results of computer
simulation of the upper & the lower hierarchy levels’ nonlinear dynamics under disturbed motion with
suppression of external disturbances by an asymptotic observer are shown, as well as the results of
computer simulation of the vehicle’s nonlinear dynamics under disturbed motion without an asymptotic
observer to allow a visual assessment of the observer’s performance by comparison. The relevance of
the work consists in the necessity of “flying platform” type vertical take-off & landing aircraft creation
to increase the effectiveness of people rescue operations in those disaster areas where helicopters &
other modern means don’t cope with a task. The scientific novelty of the work consists in synergetic
approach application to the design of the vehicle’s spatial position system equipped with an asymptotic
observer to suppress disturbing influences.