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Technical Paper

Impact of the Feeder Aerodynamics Characteristics on the Power of Control Actions in Steady and Transient Regimes

2012-10-22
2012-01-2112
In this paper we consider one of the problems in the development of control system for the feeder for MAAT transportation system. This problem is connected with estimation of inboard energy requirements. Traditionally such estimation is made on the basis of static relations. They allow assessing the power required to move a solid body with a constant air speed. However a contribution from aerodynamic forces and moments can vary depending on a regime of motion (value of linear and angular accelerations, angle of attack, etc). Because of that fact, this work investigates the estimation of the total required inboard energy and contribution of aerodynamic forces and moments to it in specified feeder motion regimes. The method of assessment is based on the feeder model, which is built on the equations of the rigid body. This paper contains general structure of feeder mathematical model, which includes equations of statics, dynamics and control mechanisms.
Technical Paper

Synthesis of Time Quasi-Optimal Asymptotically Stable Control Laws

2015-09-15
2015-01-2481
The solution of the both synthesis and implementation problems of high-rapid rates control laws is extremely important for the development of automatic control systems of the aircraft. This is due to the high speed of such vehicles. Along with this, it is imperative that control laws provide that system is asymptotically stable, as the basis for the reliability of their controlled motion. Another important objective of the method of synthesis of control laws for aircraft is compulsory compliance with strict limitations on the values of control inputs at the actuation devices. It is equally important that the control laws provides limitations on the state variables of aircraft, such as velocity, acceleration, etc. Pontryagin's maximum principle is aimed at solving such a time-optimal problem with the limited command variable.
Technical Paper

Airship Positioning Fuzzy Multi-Ballonet Control Study

2014-09-16
2014-01-2146
Airship designers research application versions of systems with several ballonets for adjustment of airship roll and/or pitch as a whole. This requires effective automatic status management of each separate ballonet. But multi-ballonet system control issue encounters the absence of industrially measurable variables of each separate ballonet status. Thus status control issue of the system becomes uncertain. The fact requires the issue studying and shaping new scientific and technical solutions. This publication represents research results implying that fairly simple implementation and effective result can be achieved by application of fuzzy control concept. Its application is built on generating the representative quantity of fuzzy production rules. They are based on present set evaluation of known parameters and measured variables. This results in fuzzy but meaningful image of ballonet system status and airship as a whole. Thus achieving fairly good control over multi-ballonet system.
Technical Paper

Identification of Traction and Power Characteristics of Air-Screw Propulsors in Mathematical Description of Airship

2014-09-16
2014-01-2134
The paper formulated and solved the problem of investigating the traction and power characteristics of air-screw propulsor for airships. The study is performed by constructing a mathematical model relating the steady-state values of the shaft power and traction on the axis of the screw with the velocity of rotation and the actual velocity of the aircraft. Proved design scheme selection of computer simulation of aero-and thermodynamic processes occurring during rotation of the airscrew. Describes plan developed under the experimental task, providing variation in the basic parameters of the airscrew, motion parameters and flight environment The results of computer modeling of the interaction of the airflow with the airscrew at various combinations of these parameters. Results are shown in tabular and graphical form and as a mathematical model of the studied airscrew.
Journal Article

Continuous-Positional Automatic Ballonet Control System for Airship

2013-09-17
2013-01-2236
This paper is devoted to a method of creating of the automated ballonet system for pressure control inside an airship envelope. Along with the study of the effects of the positional control system parameters, the authors develop novel control scheme. It is based on a new hybrid controller, which combines positional approach to forming the output control signal with a contour of continuous correction of input signal, which defines the pressure drop on the surface of the envelope as a function of the flight altitude. This approach allows reducing the effect of self-oscillations of airship envelope internal pressure on the flight altitude. In order to prove the new approach the mathematical model is being obtained. The results of the derivation and simulations of the control system operation are presented in this paper.
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