RU2225636C2 - Device of single-channel control over longitudinal motion of light baffle plane - Google Patents

Abstract

FIELD: automatic flight control systems. SUBSTANCE: invention can be employed to decrease deviation of flight altitude of baffle plane from balancing value and to reduce time of transient process of baffle plane by altitude and pitch angle. Technical result of invention consists in decreased deviation of reference flight altitude and balancing value of pitch angle under action of disturbance and in reduced time of return of baffle plane to reference flight altitude and to balancing value of pitch angle after termination of disturbance by formation of signal of nonlinear control. Device of single-channel control over longitudinal motion of light baffle plane has transmitter of pitch angle, transmitter of angular velocity, transmitter of angular acceleration, first adder, rudder assembly, former of nonlinear control signal containing unit computing modulus, amplifier, second multiplier with relay unit, first multiplier, inverter, third multiplier and second adder. EFFECT: decreased deviation of reference flight altitude and balancing value of pitch angle. 5 dwg

Description

 The invention relates to automatic flight control systems and can be used to reduce the deviation of the ekranoplane flight altitude from the balancing value, as well as to reduce the time of transient ekranoplan operations by pitch angle and height.

A device is known for two-channel control in the longitudinal movement of an ekranoplan using the elevator channel and the flap channel (Diomidov VB Automatic control of the ekranoplan movement. - SPB: SSC RF - Central Research Institute "Elektropribor", 1996) - [1, p.174]. It contains an angle sensor for obtaining a pitch angle value, an angular velocity sensor for determining the angular velocity ω _z , a radio altimeter for receiving a signal H proportional to the flight altitude above the underlying surface, amplifiers for generating control signals and steering units acting on the elevator and flaps respectively.

 The known device of two-channel control in the longitudinal movement of the ekranoplan is applicable mainly to ekranoplanes of large sizes, the flight of which is carried out at sufficiently high altitudes. Due to the fact that the error in measuring the current flight altitude by radio altimeters designed for ekranoplanes is about 0.1 m in the altitude range 0-15 m (A. Nebylov Measurement of flight parameters near the sea surface, SPbGAAP. St. Petersburg, 1994) - [ 2, p. 79], such a measurement error is unacceptable for light ekranoplanes flying at altitudes of 0.3-1 m above the surface.

 The two-channel control scheme is not always acceptable, since light winged wagons may not have flaps designed to directly control the flight altitude (with the ability to deviate in opposite directions from the neutral). The introduction of a two-channel control scheme is also limited by the requirements of mass and dimensional indicators for lightweight ekranoplanes.

 For a comparative analysis with the claimed invention, a single-channel pitch angular motion control device was used (used in the AP-15T autopilot), containing a pitch angle sensor, the output of which is connected to the first input of the adder, an angular velocity sensor connected to the second input of the adder, an angular acceleration sensor connected to the third input of the adder, serially connected amplifier, the input of which is connected to the output of the adder, and the steering unit (On-board flight control systems. / Ed. by Yu.V. Bayborod on - M .: Transport, 1975) - [3, p. 254].

будет достаточно мала. Но при наличии большого демпфирования относительно поперечной оси экраноплан будет медленнее возвращаться к балансировочному значению угла тангажа. Следовательно, более длительное время будет существовать вертикальная скорость центра масс экраноплана

, что вызовет большее отклонение экраноплана по высоте после окончания действия возмущения. Для уменьшения отклонения экраноплана по высоте после прекращения действия возмущения на этапе возвращения экраноплана к балансировочному значения угла тангажа желательно иметь меньшее значение коэффициента демпфирования.The specified single-channel control device can also be directly used on a light winged craft. At the same time, due to the ekranoplan’s own property, it will return to the reference flight altitude, and stabilization of the reference altitude will be carried out indirectly, the value of which is uniquely determined by the flight speed and balancing deviation of the elevator. But with this method and control device, there will be sufficiently large deviations of the winged wing from the reference altitude and the balancing value of the pitch angle under the action of perturbations. To reduce the deviations of the ekranoplan from the balancing (reference) flight altitude and the balancing value of the pitch angle under the action of disturbances, it is possible, without changing the structure of the autopilot, by increasing the damping coefficient of the ekranoplan relative to the transverse axis. In this case, the perturbations acting relative to the transverse axis (wave impact) will not cause a large deviation of the pitch angle relative to the balancing position, and therefore the winged wing will deviate little from the reference flight altitude, since the vertical speed due to the relation

will be small enough. But in the presence of large damping relative to the transverse axis, the ekranoplan will slowly return to the balancing value of the pitch angle. Therefore, for a longer time there will be a vertical velocity of the center of mass of the winged craft

, which will cause a greater deviation of the ekranoplan in height after the end of the disturbance. To reduce the deviation of the ekranoplan in height after the termination of the disturbance at the stage of the return of the ekranoplan to the balancing pitch angle, it is desirable to have a lower damping coefficient.

 The goal is to reduce the deviation from the reference flight altitude and the balancing value of the pitch angle under the action of a disturbance and to reduce the time of the return of the winged wing to the reference altitude and to the balancing value of the pitch angle at the end of the perturbation by generating a non-linear control signal.

 This object is achieved by the fact that in a single-channel control device in the longitudinal movement of the winged wing containing a pitch angle sensor, the output of which is connected to the first input of the first adder, an angular velocity sensor, an angular acceleration sensor connected to the third input of the first adder, the steering unit, the input of which is connected with the output of the first adder, a nonlinear control signal generating unit is additionally introduced, the first input of which is connected to the output of the pitch angle sensor, the second input is connected to the output m, the angular velocity sensor and the output of which is connected to the second input of the first adder, containing the module calculation unit, the amplification unit, and the second multiplication unit with the relay unit, the first multiplication unit, an inverter, the input of which is connected to the output of the first multiplication unit, the first and second the input of which is connected respectively to the outputs of the amplification unit and the relay unit, the first input of the third multiplication unit is connected to the inverter output, the output of the third multiplication unit is connected to the first input of the second adder a, the second input of which is connected to the second input of the third multiplication unit and the second input of the second multiplication unit, which are the second input of the non-linear control signal generating unit, the first input of the non-linear control signal generating unit is the input of the module calculation unit, connected to the first input of the second multiplication unit, and the output of the non-linear control signal generating unit is the output of the second adder.

 The invention is illustrated in figures 1 and 2.

 Figure 1 presents a block diagram of a single-channel control device in the longitudinal movement of a light winged craft; figure 2 is a block diagram of an implementation of the block forming a nonlinear control signal.

The device contains:
1 - pitch angle sensor;
2 - angular velocity sensor;
3 - angular acceleration sensor;
4 - block forming a nonlinear control signal;
5 - the first adder;
6 - steering unit.

- сигнал, снимаемый с датчика углового ускорения 3;
φ_в - угол поворота руля высоты.The following notation is accepted:
k _ν ν is the signal taken from the pitch angle sensor 1;
i _ω ω _z - signal taken from the angular velocity sensor 2;

- signal taken from the angular acceleration sensor 3;
φ _in - angle of elevator.

 The output of the pitch angle sensor 1 and the output of the angle acceleration sensor 3 are respectively connected to the first and third inputs of the first adder 5. The first and second input of the non-linear control signal generating unit 4 are connected to the outputs of the pitch angle sensor 1 and the angular velocity sensor 2, respectively. The output of the non-linear control signal generating unit 4 is connected to the second input of the first adder 5. The output of the first adder 5 is connected to the input of the steering unit 6.

Block forming a nonlinear control signal (figure 2) contains:
7 - unit calculation unit;
8 - gain block;
9 - the first block of multiplication;
10 - the second block of multiplication;
11 - relay block;
12 - inverter;
13 - the third block of multiplication;
14 - second adder.

 The non-linear control signal generating unit contains a series-connected calculation unit of module 7, a gain unit 8, and a second multiplication unit 10 with a relay unit 11, a first multiplication unit 9, an inverter 12, the input of which is connected to the output of the first multiplication unit 9, the first and second inputs of which connected respectively to the outputs of the amplification unit 8 and the relay unit 11, the first input of the third multiplication unit 13 is connected to the output of the inverter 12, the output of the third multiplication unit 13 is connected to the first input of the second adder 14, the second input of which of the second is connected to the second input of the third multiplication unit 13 and the second input of the second multiplication unit 10, which are the second input of the non-linear control signal generating unit 4, the first input of the non-linear control signal generating unit 4 is the input of the module 7 calculation unit, connected to the first input of the second multiplying unit 10 and the output of the non-linear control signal generating unit 4 is the output of the second adder 14.

 The operation of the device is as follows.

где М - некоторый постоянный коэффициент; ϑ - текущее значение угла тангажа.When a perturbation appears, acting relative to the OZ axis of an ekranoplan, the angular velocity ω _z appears. A signal proportional to the angular velocity ω _z is taken from the output of the sensor 2 and fed to the second input of the non-linear control signal generating unit 4. The action of the disturbance will also cause the pitch angle to deviate from the balancing value. The signal from the output of the sensor 1, proportional to the deviation of the pitch angle from the balancing value, is fed to the first input of the first adder 5 and to the first input of the non-linear control signal generating unit 4. In the presence of angular acceleration, the sensor 3 generates a signal arriving at the third input of the first adder 5. Block forming a non-linear control signal 4 generates a signal of the form
i $\genfrac{}{}{0ex}{}{\text{*}}{\text{ω}}$ ω _z = i _ω (lk) ω _z ,
where i _ω is the calculated value of the damping coefficient in a linear system, ω _z is the angular velocity;

where M is a constant coefficient; ϑ is the current value of the pitch angle.

 The formation of a nonlinear control signal occurs as follows.

 A signal proportional to the current value of the angular velocity from the second input of the non-linear control signal generating unit 4 is fed to the second input of the second multiplication unit 10, the second input of the third multiplication unit 13 and to the second input of the second adder 14. The signal proportional to the pitch angle is fed to the input of the unit the calculation of module 7 and the first input of the second multiplication block 10. The calculated module of the current value of the pitch angle from the output of block 7 enters through the amplification block 8 with a gain of M at the first input of the first block intelligently 9. From the output of the second multiplication block 10, the product of signals proportional to the current values of the pitch angle and angular velocity is fed to the input of the relay unit 11. The relay unit 11 generates a signal equal to either zero or unit value, depending on the signs of the current values of the pitch angle and angular velocity. From the output of the relay unit 11, the signal is supplied to the second input of the first multiplication unit 9. Depending on the signal value at the output of the relay unit 11, the coefficient K at the output of the first multiplication unit 9 takes either a zero value or a value proportional to the current value of the pitch angle. From the output of the first block of multiplication 9 through the inverter 12, the signal is supplied to the first input of the third block of multiplication 13. From the output of the third block of multiplication 13, the signal is supplied to the first input of the second adder 14. From the output of the second adder 14, the generated control signal is supplied to the second input of the first adder 5.

 At the first adder 5, the control signals coming in with their gains are added. From the output of the first adder 5, the received signal is fed to the input of the steering unit 6. The steering unit directly affects the elevator and deflects it in the direction of counteracting external disturbance.

 Thus, the single-channel control device in the longitudinal movement of the light winged wing reduces the deviation of the winged wing from the reference altitude caused by a disturbance and reduces the time of return to the reference altitude due to the introduction of nonlinear control of the damping coefficient. This statement is confirmed by the transient graphs shown in FIGS. 3-5. These graphs were obtained as a result of mathematical modeling of the Ekranoplan - Control System system using a computer. Wave shock and vertical wind are accepted as typical disturbing influences.

 In FIG. Figure 3 shows the change in pitch angle when exposed to a vertical speed of 5 m / s. The number 1 indicates the transient process when using the non-linear control signal generating unit, and the number 2 indicates the transient process with the linear control method. The decrease in the deviation of the pitch angle value from the balancing value is clearly seen in the case of using the non-linear control signal generating unit. When using the non-linear control signal generating unit, the pitch angle deviation from the balancing value is more than halved. With a perturbation in the form of a vertical gust of wind at a speed of 5 m / s, the transient process with respect to the relative flight height when using the non-linear control signal generating unit does not differ significantly from the transient process when using the linear control system.

 In FIG. 4 shows pitch transients under the influence of a disturbance in the form of an angular velocity of 5 deg / s. The angular velocity is caused by the impact of an ekranoplan against an agitated water surface. The number 1 indicates the transient process when using the non-linear control signal generation unit, and the number 2 indicates the transient process with the linear control method. Noticeable is the decrease in the deviation under the action of the perturbation, as well as the reduction in the return time to angles close to the balancing value when using the non-linear control signal generating unit.

 Figure 5 presents the transients in relative flight altitude when exposed to disturbances in the form of an angular velocity of 5 deg / s. The number 1 indicates the transient process when using the non-linear control signal generation unit, and the number 2 indicates the transient process with the linear control method. When using the non-linear control signal generating unit, both the deviation due to the disturbance and the reduction of the return time to the reference flight altitude are reduced.

 The device includes easy-to-implement circuits, consisting of publicly available elements, and is characterized by small overall dimensions and low power consumption.

 This device can be used not only on light winged planes, but also on aircraft, when controlling angular movement and flight altitude, where the introduction of a non-linear control signal generating unit will also be effective.

Claims (1)

A single-channel control device in the longitudinal movement of a light winged craft containing a pitch angle sensor, the output of which is connected to the first input of the first adder, an angular velocity sensor, an angular acceleration sensor connected to the third input of the first adder, a steering unit, the input of which is connected to the output of the first adder, characterized in that an additional block for generating a nonlinear control signal is introduced, the first input of which is connected to the output of the pitch angle sensor, the second input is connected to the output of the angle sensor the new speed and the output of which is connected to the second input of the first adder, containing series-connected module calculation unit and amplification unit, as well as a second multiplication unit with a relay unit, a first multiplication unit, an inverter, the input of which is connected to the output of the first multiplication unit, the first and second inputs which are connected respectively to the outputs of the amplification unit and the relay unit, the first input of the third multiplication unit is connected to the inverter output, the output of the third multiplication unit is connected to the first input of the second adder, w the swarm input of which is connected to the second input of the third multiplication unit and the second input of the second multiplication unit, which are the second input of the non-linear control signal generating unit, the first input of the non-linear control signal generating unit is the input of the module calculation unit connected to the first input of the second multiplication unit, and the output of the unit forming a non-linear control signal is the output of the second adder.

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