SU857939A1 - System for control of normal g-load of aircraft with devices for direct control of lift force - Google Patents

Description

pitch speeds connected to the second and third inputs of the amplifier of the adder; an amplifier is inputted, the input of which is connected to the output of the amplifier-accumulator, and the output to the drive of the organs for direct control of the lifting force.

The gain of the amplifier is selected from the condition of compensation of the elevator force of the elevator with the elevating force of the direct lift force control units (LLSS).

FIG. 1 is a block diagram of a normal overload control system / FIG. 2 - plots of stability regions in the plane of the coefficients, amplification of the amplifier-adder according to signals from the integrator T) and the pitch / L angular velocity sensor before and after the introduction of an additional amplifier with a gain factor K through which the control signal passes to the NHPS; in FIG. 3, the graphs of transients of a normal overload control before and after the introduction of an additional amplifier, and also after an increase in the gain factors of the adder amplifier, which becomes possible by expanding the stability regions after the introduction of an additional amplifier.

The normal overload control system (Fig. 1) contains a block 1 comparing the set and current values of the normal overload, the output of which through the integrator 2 is connected to the input of the amplifier-adder 3, to the other two inputs of which the normal overload sensors 4 and the angular velocity sensor 5 are connected, Moreover, to the output of the amplifier of the adder 3, a rudder drive 6 of height connected to the rudder 7 of height and an amplifier 8 is connected, through which the control signal is fed to the input of the drive 9 of the NUMS, which controls the NUPS 10.

The proposed system works as follows.

Traditional normal overload control is accomplished using a elevator. When the elevator is deflected, a lift force arises on it. Due to the fact that the elevator is significantly removed from the center of gravity of the aircraft, its deviation leads to a significant longitudinal aerodynamic moment, under the action of which the aircraft body rotates relative to the trajectory, the angle of attack changes and, consequently, the lifting force. Thus, the elevator acts on the lifting force indirectly through the longitudinal aerodynamic moment created by it. Moreover, when the rudder of the aircraft height of a normal aerodynamic configuration (with the rear tail position) deviates, a lift force arises on it that is opposite to the lift force, which results from a change in the angle of attack. That is why in the known system there is a negative overload on the overload in the initial stage of the transition process (graph 1, fig. 3).

An additional circuit formed by the amplifier 8, the drive 9, and the organs 10 of the NHPS allows to eliminate the influence of the positive feedback caused by the elevating force of the roll 7 of height.

In the proposed system for testing a given overload, the rudder 7 of the height and the 10 NSPS bodies, whose lifting forces are equal in magnitude and opposite in direction, are simultaneously deflected. As a result, the elevator force 7 of the elevator is compensated for by the elevator force of the organs 10 of the NHPS and only the steering moment, generated mainly by the elevator 7, acts on the aircraft. This significantly increases the stability of the system by the integral of the error signal and the signal of the angular velocity of the pitch. This effect is illustrated by the stability regions (Fig. 2), obtained under the assumption that the gain of the amplifier-adder 3 according to the signal from sensor 4 is constant. In this case, curve 1 corresponds to the stability region of the known system, curve 2 corresponds to the mode when the control signal from the output of the amplifier-adder 3 goes to the actuator 9 of the NHPS through the amplifier 8, the gain 1 of which is selected from Conditions for compensating the lifting power of the stabilizer with the lifting power of the organs

Claims (2)

FIG. 2, the graph corresponds to the transition function of the proposed system when the transmission coefficients of the amplifier-adder 3 remain unchanged. The smoother nature of the transition function 2 illustrates the reduction in the oscillation of the normal overload control processes and the absence of a back reaction in the initial stage of the transition process. Since the use of an additional chain of control signal transmissions through aircraft to the aircraft expands the area of stability, it is possible to significantly increase the gain factors and the values to which the stability margin approaches that of a known system. In this case, a significant increase in speed is achieved / that |} is illustrated by curve 3 (Fig. 3), which indicates approximately twice as fast as the proposed system compared to the known, Invention 1. The control system for normal overload of the aircraft with direct control of lift containing a series-connected comparison unit, integrator, amplifier-adder and elevator drive, as well as normal overload and angular velocity sensors connected to watts ORS 1U and the third input amplifier-suppressor, meaning that, in order to increase the dynamic stability and speed of the system, it contains an amplifier, the input of which is connected to the output of the amplifier-suppressor, and the output to the drive of the organs of direct control of lifting force, 2. The system of claim 1, so that the gain factor of the amplifier is chosen from the condition of compensation of the elevating force of the elevator by the force of the organs of direct control of the lifting force. Sources of information taken into account in the examination 1, Topcheev Yu.I. and other systems of stabilization. M ,, Mechanical Engineering, 1974, p. 115. 2, Pashkovsky I.M. Stability and aircraft control. Moscow, Mashinostroenie, 1975, p. 41, 3, Mikhalev I.A., et al. Auto aircraft control systems. M., Mechanical Engineering, 1971, p. 149 (prototype. “U fut.