RU2312793C1 - Aircraft flight automatic control system - Google Patents

Abstract

FIELD: aircraft flight control equipment with processor control sets.

SUBSTANCE: proposed system includes duplicated digital computer, servo units connected in parallel with elevator, aileron and rudder manual control system, auto-throttle actuating mechanism connected in parallel with port and starboard engine manual control system, control panel, control stick and force indicator. Proposed system is engageable with information systems, such as heading vertical, radio altimeter, air data, navigation and landing system, engine electronic control system, electrical trimming mechanisms and warning system. Device for ground checks and monitoring which is component of digital computer makes it possible to indicate area of failure and to display numerical values of parameter selected from total list of parameters of engageable systems and parameters of automatic control system.

EFFECT: enhanced efficiency of diagnosis; ease of operation; enhanced accuracy and reliability of automatic control system.

5 cl, 7 dwg

Description

The claimed invention relates to aerobatic flight equipment with processor control kits and is intended for use in automatic control of an airplane.

Flight control systems are known, for example, systems for civil aircraft of the Airbus family, in particular Airbus 330. This system is designed with a computing part, which includes processors included in the structure of combined information exchange with digital data buses ARINC 429. The digital data bus ARINC 429 is a centralized multi-reception unidirectional data bus and defines a standard for digital data exchange between avionics systems. In the known system for inputting pitch and roll commands, side control knobs located on the side consoles are used, course control is carried out using the rudder pedals [FLIGHT CONTROL SYSTEMS practikal issues in design and implementation, Edited by Roger W. Pratt, IEE Control enginnttring series 57, 2000, p. 34-39].

Other control systems are also known (WO 01/93039 A1, G 06 F 11/16, 12/06/2001; RU 2235042 C1, B64C 13/00, G06F 13/00, 12/12/2003; RU 2235043 C1, B64C 13/00 , G06F 13/00, 11/12/2003), the closest of which, by technical nature, to the claimed one is the aircraft control system described in patent RU 2235043, one of the functions of which is automatic flight control.

The known automatic control system contains a redundant digital computer, steering gears, a command system for controlling engine thrust, a control panel, a control handle, a force indicator and a system operation monitoring device. The automatic control system is interfaced with vertical directional systems, air signals, navigation and landing, a radio altimeter, an electronic engine control system, trim mechanisms and an alarm system.

The device drive control system contains a set of power amplifiers, included with the possibility of amplifying the input signals and issuing control current to the control windings of the electric actuators, as well as amplifiers for receiving and closing the internal contours of the steering drives.

The system control device is configured to search for a failed removable unit, test control, make adjustments and direct parameters to external digital indicators.

The known device for automatic trimming operates on the signal of the output amplifier of the steering machine and includes an electromechanism for trimming when the threshold value of this signal is exceeded for a certain period of time (RU 1548983 A1, B64C 13/00, 11/19/1987).

This automatic control system is characterized by advanced functionality and provides stabilization of the angular position, altitude, instrument speed, altitude and course control, approach, as well as command control of engine thrust through recommendations through the ARO and an indication system of the required engine operation mode.

However, this system, as well as the on-board flight data recording system (RU 2101755 C1, G06F 7/00, 02/04/1992), does not provide for the display of numerical values of parameters, in particular, in the conditions of pre-flight verification, which does not correspond to the on-line diagnostics of the system status automatic control.

The objective of the invention is to eliminate this drawback and provide operational diagnostics, as well as simplifying operation, improving the accuracy and reliability of the automatic control system.

To solve this problem, an automatic control system is proposed, which contains a duplicated digital computer, steering machines, connected in parallel to the manual control system for elevators, ailerons and rudders, an actuator for automatic traction, connected in parallel to the manual control system for the left and right engines, a control panel, control handle and force indicator, coupled with information systems, which are used for vertical direction, radio altimeter, air systems ear signals, navigation and landing, with an electronic engine management system, trim mechanisms and an alarm system.

The solution to this problem is provided by the following private essential features of the invention.

Each of the channels of the duplicated digital computer of the system functionally consists of a receiver of signals of information systems, a converting device of input information, a computing device of control signals, including a device for ground checks and control, a device for the auto-trimmer and a device for converting the device of the calculated control signals to transmit them to steering machines interfaced with the calculator, the actuator of the traction machine and the trimmer electromechanism vania.

The device of ground checks and control is made with the possibility of determining the place of failure accurate to a removable unit, test control and an additional possibility for ground control of displaying on the panel the numerical values of the selected parameter from the general list of parameters of interfaced systems and own parameters of the automatic control system.

An automatic trim device comprising a steering machine connected to a force indicator and a calculator, the output of which is connected to a trim mechanism and an alarm system, is configured to calculate, by the magnitude of the current in the control winding of the steering machine electric motor, the control signals for the trim mechanism, a signal for indicating forces overcome by the steering machine, and a warning signal for the alarm system.

The servo device is digitally controlled and functionally includes a duplicated digital computer and a steering machine, the input of which is connected to the outputs of the computer through a logic device that implements the dependence of the calculated control signal for the engine of the steering machine on one-time signals of turning on simultaneously two or one channel of the computer when disconnecting or the failure of one of the channels, and the output of the steering machine is connected to the inputs of the computers through feedback circuits.

The device of the traction machine of the inventive automatic control system is made with duplicated channels of the actuator with the ability to replace the failed channel with another fully prepared for operation, while maintaining the characteristics and control parameters of the actuator of the traction machine before and after replacing its channels when operating from two or from one of two channels of the duplicated computer.

For ease of control during automatic control of the roll, pitch and heading angles, the control handle is made in the form of separate rotary roll and heading devices having a common axis of rotation, providing pitch control by tilting the rotary devices in a plane parallel to the plane of symmetry of the aircraft.

The invention is illustrated by drawings, where Fig. 1 is a structural diagram of an automatic control system, Fig. 2 is a functional diagram of a digital duplicated computer, Fig. 3 is a block diagram of an automatic trimmer device, and Fig. 4 is a block diagram of a servo device , Fig.5 is a functional diagram of a digital control of the steering servo machine, Fig.6 is a block diagram of a traction machine, Fig.7 is a structural diagram of a control handle.

The automatic control system (Fig. 1) contains a duplicated digital computer 1, steering machines 2, controlling the angular position of the elevator, rudder and ailerons, a duplicated actuator 3 of the traction machine, controlling the angular position of the control levers of the right and left engines (ORE), a remote control 4 for switching on various automatic control modes, a control handle 5 for automatically controlling the angular position of the aircraft and a force indicator 6 informing the pilots about the magnitude and direction of the aircraft Steering gear 2.

The automatic control system is interfaced with duplicated information systems of the 7 avionics kit (heading system, air signals, navigation and landing, radio altimeter), the information of which is used for automatic and director control of the aircraft, as well as with an electronic engine control system (not shown in the drawing), an electromechanism 8 trim and 9 alarm system, informing pilots about emergency situations in flight, including information about unacceptably large efforts, overcome left steering machine in the process of automatic control.

Duplicated digital computer 1 (figure 2) contains two identical channels, each of which functionally consists of a receiving device 10 of the signals of information systems 7, a converting device 11 of the input information, a computing device 12 of the control signals, a converting device 13 of the calculated control signals for transmitting them to mating mechanisms 8 trimmings connected to the computer, steering machines 2 and a traction machine. The calculator 1 also contains a ground control device (not shown in the drawing) made with the possibility of determining the place of failure accurate to a removable unit, a test control and an additional capability for ground control of indicating the numeric values of the selected parameter from the general list of parameters of the interfaced systems and own automatic control system parameters.

The automatic trimming device (Fig. 3) functionally includes a steering machine 2, which is used as a steering machine with a contactless DC motor with an electronic collector, a force indicator 6 and a calculator 1, the output of which is connected to the trimmer electromechanism 8 and to the emergency system 9 alarm.

The servo device (Fig. 4) contains a duplicated calculator 1 and a steering machine 2. The outputs of the converting devices 13 of the calculator 1 are connected via a logic device 14 to the control winding of the engine 15 of the steering machine 2. The outputs of the steering machine 2 are connected via feedback circuits to the inputs of the converting devices 11 calculator 1.

The servo device is digitally controlled by the steering machine. The circuit that implements digital control (figure 5), contains a computing device 12 of the control signals, conventionally represented as an adder, a converting device 13 of the calculated control signals made in the form of a digital-to-analog converter (DAC), a converting device 11 of the input information, made in in the form of an analog-to-digital converter (ADC), and the steering machine 2, presented in the form of a proportional link with a proportionality coefficient K.

The device of the traction machine (Fig.6), providing automatic control of the thrust of the aircraft engines, includes a duplicated computer system 1 and a duplicated actuator 3 of the traction machine (IMAT), made with the possibility of replacing the failed channel with another fully prepared for operation, while maintaining the characteristics and control parameters of the actuator of the traction machine before and after replacing its channels when operating from two or one of the two channels of the duplicated computer 1.

Through each of the two control channels, the rotation of the IMAT electric motor through the gearbox and the irreversible clutch is transmitted to the common planetary gearbox (differential), from which the gears are transmitted to the two output shafts through gearboxes, electromagnetic clutches, and a friction clutch for overpowering.

The communications on the IMAT indicated on the block diagram contain the calculated control and switching signals, and those on the calculator contain signals on the position, speed and torque of the IMAT output shafts.

In order to ensure an operational transition during automatic control from the stabilization mode to the control mode, the system controls are constructed so that on the remote control 4, usually located at the top of the dashboard, are concentrated all the controls except the controls for the angular position of the aircraft. They are concentrated in the control handle 5 (Fig. 7), placed on the plane in a more convenient place for its operational use and allowing separate control of the roll, heading and pitch angles with automatic control.

The control handle 5 includes two rotary devices. The rotary device 16 roll, through which the pilot automatically sets the desired roll with the desired roll, contains a gear wheel for transmitting rotation to the sensor 17 of a given roll and a disk on which a sensor 18 of a given course is fixed. The rotary device 19 of the course contains a gear for transmitting rotation to the sensor 18 of a given course and when rotating the rotary device 16 of the roll rotates with it.

The set course is displayed by the pilot by rotating the rotary device 19 of the course relative to the rotary device 16 roll. The rotary devices 16 and 19 are placed in a frame that can rotate relative to the base along an axis perpendicular to the common axis of the rotary devices. A sensor 20 of a given pitch is mounted on the base of the handle. To control the pitch angle during automatic control, the pilot tilts the rotary devices 16 and 19 along the axis of rotation of the frame, overcoming the tension and compression of the centering springs 21.

All the functions inherent in this automatic control system are performed by the system using the information of the vertical directional system, air signal system, navigation and landing equipment, received via code lines according to GOST 18977-79 and RTM 1495-75 with amendment 3 or according to ARINC-429 in accordance with the protocols of information interaction. Using this and all other information on which the system works, when conducting ground-based built-in control according to the test program, all modes of its operation are checked.

A more detailed idea of automatic control in one mode or another develops during selective viewing on the remote control 4 in ground conditions of the numerical values of the input, output and intermediate parameters of the system and parameters characterizing the conjugation of the entire complex of aircraft systems providing automatic flight control.

With the selected combination and the time of pressing certain buttons of the remote control 4, the code program for viewing the parameter on two digital displays of the set values of the flight level and the course with the display of the serial number of the parameter is set using the flight height dial located on the remote control (not shown in the drawing).

The structure of the parameters includes:

- information parameters of interfaced avionics systems (30),

- parameters of the state of the devices of the automatic control system (40),

- output control parameters (20),

- parameters of the internal state of calculators (70), including intermediate algorithmic signals, echo signals, signals of mathematical models and dynamic characteristics of servos and others.

In parentheses is the rounded number of parameters calculated in each channel of the calculator 1.

Each channel of the calculator 1 performs:

- receiving and converting signals for computing input information,

- calculation of control signals, including ground check devices, auto trimmer, servo drive, traction machine,

- the conversion of the calculated control signals to transmit them in mates with the calculator blocks.

When viewing the parameters, their temporary stability, numerical value, parametric determination of the cause of the negative result of the built-in ground control according to the test program and observations in flight with a positive result of the test control, the mutual correspondence of the parameters of the port and starboard are revealed. Moreover, for the efficiency of checks, the parameters of the left computer and the conjugated avionics systems of the left side are initially displayed, which are replaced by the corresponding parameters of the right computer and the conjugated systems of avionics of the right side for the time that a certain remote control switch 4 is pressed.

The implementation of the code program is ensured by the information exchange between the calculator 1 and the remote control 4. Hardware and software exclude the possibility of including ground test control programs and viewing parameters in flight. Among these tools is the use of the compression signal of the chassis.

As power actuators of the system used steering machines 2 with a non-contact DC motor 15 with an electronic collector. A particular essential feature of the invention defines a device for automatic trimming, built on the basis of the said steering machines.

In idle mode, the motor torque is balanced by the moment of counter-emf resulting from the rotation of the armature in the field of excitation of the engine, and in the braking mode it is balanced by the load moment with maximum current in the control winding of the motor. In intermediate values of the external load under the action of counter-emf current in the control winding decreases. On this basis, a torque signal is provided in the steering machine 2 of the system, proportional to the initial current value in the control winding of the engine.

For automatic trimming and indication of the forces in the cockpit overcome by the steering machine 2, the torque signal of the steering gear is applied through a large-scale resistor to the force indicator 6 located in the cockpit. The same signal enters the computer 1 of the system, in which control signals for moving the trim mechanism 8 are calculated, according to which the aerodynamic steering trimmer is deflected in the direction of decreasing control efforts.

Trimming electromechanism has a relay type of control and moves to one side or another at a constant speed, which is taken into account when developing the structure of control signals.

The device operates as follows. When the signal of the moment of the steering machine 2 increases and this signal exceeds a certain threshold for a certain time, a trim control signal is generated. Moving the trimmer reduces wiring stress and torque signal. The control signal is removed when the torque signal is reduced to a certain level. If this reduction does not occur, then after a certain time, in the calculator 1, a warning command is generated for the alarm system display 9.

Typically, in automatic control systems, servo drives are used, combining an electromechanical steering machine and a servo amplifier, generating its control signal depending on the control signal of the calculator and feedback signals.

A particular essential feature of the invention is the exclusion of the servo amplifier and generation of a steering machine 2 control signal in the digital computer 1. When digitally controlling the actuators, the time quantization of the computing process must be taken into account when implementing the servo.

. Представим контур управления, состоящий из рулевой машины, охваченной единичной отрицательной обратной связью. Передаточная функция контура

.In the very first approximation, the transfer function of the steering machine 2 can be approximated by a proportional link with a transmission coefficient K in dimension

. Imagine a control loop consisting of a steering machine covered by a single negative feedback. Loop transfer function

.

According to the flight parameters in the digital computer 1, a control value X is generated, in proportion to which the value Y of the continuous actuator should be. The system implements the dependence Y _n = K (X _n -Y _n-1 ), while the difference X _n -Y _n-1 , which remains constant for the quantization period T, is then replaced by the difference X _{n + 1} -Y _n .

To determine the transient response of the system, we form a stepwise effect corresponding to an increase from zero to unity of the value Y.

, величина X определяется обратной величиной этого коэффициента или передаточной функции. Величину X будем оставлять неизменной во всех последующих тактах работы цифрового вычислителя.In a system that is initially in zero initial conditions (X ₀ = Δ ₀ = Y ₀ = 0) and taking into account its analog transmission coefficient

, the value of X is determined by the reciprocal of this coefficient or transfer function. The value of X will be left unchanged in all subsequent clock cycles of the digital computer.

The reaction of the system is simply determined taking into account its state in the previous step:

X A = X _n -Y _n-1 Y = KΔ N 0 0 0 0

1 + K one

1-K ² 2

1 + K ³ 3

With a stepwise action, the output value in general is determined by the expression:

Y _n = 1 - (- K) ⁿ .

The reaction of the system is characterized by oscillations with a period of 2T relative to the equilibrium state equal to unity. Oscillation damping occurs only at K <1, which is the stability boundary of the system.

Fulfillment of the requirements for the nature of the transition process of the system has an unambiguous relationship with the value K. For example, if the tolerance of two oscillations before entering the 5% tube is normalized, this requires Y ₅ ≤1.05 or K ⁵ = 0.05. The regulation time in this case is 4T.

, то она может не учитываться, так как в конце такта выходная величина достигает величины управляющего сигнала. При Т больших значениях (

) за счет запаздывания в конце такта управляющий сигнал отрабатывается не полностью, и это обстоятельство можно интерпретировать как снижение коэффициента усиления выходного звена, то есть для целей нашего анализа величина К должна быть представлена произведением, одним сомножителем которого является коэффициент передачи пропорционального звена К_пр, а второй сомножитель численно равен той части управляющего сигнала, которая успевает приблизить заданное значение к текущему в конце такта К_Δ:The foregoing also applies to the case when the proportional link in the system is replaced by an aperiodic link. If the time constant T of the aperiodic link

, then it may not be taken into account, since at the end of the clock the output value reaches the value of the control signal. At T large values (

) due to the delay at the end of the clock, the control signal is not fully processed, and this circumstance can be interpreted as a decrease in the gain of the output link, that is, for the purposes of our analysis, the value of K must be represented by the product, one factor of which is the transmission coefficient of the proportional link K _pr , and the second factor is numerically equal to that part of the control signal that manages to bring the set value closer to the current value at the end of the cycle K _Δ :

K = K _pr · K _a , where

Taking into account the above starting differences in the digital implementation of the servo drive from the known analogue, the maximum permissible slope of the feedbacks, the correcting links in them, and also the clock frequency of calculating the parameters of the servo drives of the system are determined.

In each calculator 12 (Fig. 5), according to the current flight parameters and signals of the steering machine 2, by its position, speed, and moment, a control signal is calculated, which arrives together with the steering machine power-on signal at one of the inputs of the logic device 14. At its output, the logical device 14 generates a control signal and a power-on signal of the steering machine 2. The output of the logic device 14 receives only one of the two control signals, which is accompanied by a power-on signal of the steering machine 2.

Upon receipt of two turn-on signals of the steering machine 2 in the logical device 14, the logical device generates at its output a half-sum of control signals. In each calculator 12, according to the current flight parameters and the position and speed signals of the steering machine 2, as well as the moment signal on the shaft of the steering machine 2, the operation of the servo drive, its accuracy and dynamic characteristics are monitored.

According to the test program before the flight, the operation of the traction machine is sequentially checked first from one, then from another IMAT channel.

When the thrust automaton is switched on in flight, the conformity control of the mathematical model of the actuator mechanism and the mathematical model of the thrust automaton included in the calculator program is continuously monitored. In case of violation of compliance only with the mathematical model of the actuator with the current parameters, the working actuator is switched off and the backup actuator is turned on, checked before the flight and fully prepared for work. Due to irreversible couplings in the actuators, an unambiguous correspondence is ensured between the movement of the engine of the actuator included and the output shafts of IMAT.

The movement of the engine is transmitted only to the output shaft of the differential, because the other input of the differential is jammed by an irreversible clutch of the disconnected engine.

The conjugation of the calculator with IMAT is performed in such a way that each actuator is controlled from two channels of the duplicated calculator, and information from two actuators and IMAT is supplied to each computational channel. The actuator works by the sum of the signals of the channels of the computers. To maintain operability when one of the calculator channels is switched off in a working channel, the steepness of the control signals entering the IMAT doubles.

Based on the foregoing, it is obvious that the set of essential features that characterize the claimed automatic flight control system of the aircraft, and the corresponding implementation of the private essential features provides a technical result, which is expressed in providing operational diagnostics of the system, simplifying its operation, improving accuracy and reliability.

Claims (5)

1. The automatic flight control system of the aircraft, containing a duplicated digital computer, steering machines, connected in parallel to the manual control system of the elevator, ailerons and rudders, an actuator of the traction machine, connected in parallel to the manual control system of the left and right engines, a control panel, a handle control and indicator of effort, coupled with information systems, which are used as a vertical line, radio altimeter, air signal systems, navigation and landing, with an electronic engine management system, trim mechanisms and an alarm system, characterized in that in a duplicated digital computer, each of whose channels functionally consists of a receiver of signals of information systems, a converting device of input information, a computing device of control signals, including a ground check and control device, a self-trimmer device, and a servo drive, a converting device calculated x control signals for transmitting them to steering machines that are interfaced with the calculator, an actuator of the traction machine and an electromechanism for trimming, a ground-based inspection and control device is configured to determine the place of failure with an accuracy of a removable unit, test control and an additional option for ground control indication on the remote control the numerical values of the selected parameter from the general list of parameters of interfaced systems and own parameters of the automatic control system. 2. The system according to claim 1, in which the automatic trimming device comprising a steering machine connected to a force indicator and a calculator, the output of which is connected to the trim mechanism and to the alarm system, is configured to calculate the magnitude of the current in the control winding of the electric motor of the steering machine control signals for the trimmer electromechanism, a signal to indicate the forces overcome by the steering machine, and a warning signal for the alarm system. 3. The system according to claim 1, in which the servo device is digitally controlled and functionally includes a duplicated computer and a steering machine, the input of which is connected to the outputs of the computers through a logic device that implements the dependence of the calculated control signal for the engine of the steering machine on one-time enable signals at the same time two or one channel of the calculator when one of the channels is disconnected or failure, and the output of the steering machine is connected to the inputs of the calculators through feedback circuits. 4. The system according to claim 1, in which the device of the traction machine is made with duplicated channels of the actuator with the ability to replace the failed channel with another fully prepared for operation, while maintaining the characteristics and control parameters of the actuator of the traction machine before and after replacing its channels during operation from two or from one of the two channels of the duplicated computer. 5. The system according to claim 1, in which, for ease of control in the automatic control of the roll, pitch and heading angles, the control handle is made in the form of separate rotary roll and heading devices having a common axis of rotation, providing pitch control by tilting the rotary devices in a plane parallel to the plane of symmetry of the aircraft.

Images