Logical layout for an integrated terminal aircraft control system using linear and relay controllers

Control and navigation systems


Lebedev G. N.*, Vu X. H.**

Moscow Aviation Institute (National Research University), 4, Volokolamskoe shosse, Moscow, А-80, GSP-3, 125993, Russia

*e-mail: kaf301@mai.ru
**e-mail: vuxuanhuong1984@gmail.com


This research is discussing a terminal aircraft control system of improved performance.
The aim was to develop the necessary logical structure for an integrated terminal aircraft control system, including linear and relay-based controllers.
Methodology: the tasks of guiding a vessel to a terminal point has always been a subject of primary interest in aircraft control. From the point of view of variation calculus, these tasks may be decomposed into a fixed and a mobile endpoints terminal control task. In the most common case, there is an endpoint with several undefined coordinates or with some additional constraints. This paper addresses one of these tasks — the problem of landing an aircraft on a given point of the runway, which is especially important for small allowable landing roll distances, and the problem of mooring an airship to a mast with a zero terminal velocity.
Achievements: this work proposes a structure for a terminal control system of higher performance, composed of a logical and an executive part. The logical part consists of a bloc estimating the remaining flight time, also in charge of the coordinated control in the lateral and longitudinal channels, and of two logic analyzer, tracking sign coincidences of deviations in position and velocity for lateral and longitudinal control channels. The executive part contains of two linear and two relay controllers, the first pair is used to assure cautious and soft docking, and the second pair — to improve the performance of significant deviation tracking.
Area of application: on aircrafts, expected to perform frequent landings.
Conclusions: The resulting control system structure is applicable on airships, where it’s important to shorten the time of approach to a desired endpoint, as well as on aircrafts, expected to perform landings in similar challenging conditions.


jet, airship, logic, terminal point, optimal control, linear regulator, relay regulator, mooring, landing


  1. Lukomskiy Yu.A., Korchanov V.M. Upravlenie morskimi podvizhnymi obektami (Control of marine movable objects), Saint Petersburg, Elmor, 1996, 318 p.
  2. Grishanin Yu.S., Lebedev G.N., Lipatov A.V., Stepanyants G.A. Teoriya optimalnykh sistem (The theory of optimal systems), Moscow, MAI, 1999, 317 p.
  3. Pontryagin L.S. Printsip maksimuma v optimalnom upravlenii (The maximum principle in optimal control), Moscow, Nauka, 1989, 62 p.
  4. Bellman R. Dinamicheskoe programmirovanie (Dynamic programming), Moscow, IIL, 1961, 400 p.
  5. Letov A.M. Matematicheskaya teoriya protsessov upravleniya (The mathematical theory of control processes), Moscow, Nauka, 1981, 255 p.
  6. Lebedev G.N., Vu X.H. Elektronnyi zhurnal “Trudy MAI”, 2013, no. 63, available at: http://www.mai.ru/science/trudy/published.php?ID=36114 (accessed 08.02.2013)


mai.ru — informational site MAI

Copyright © 2000-2024 by MAI