RU1837033C - Helicopter autopilot - Google Patents

Description

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The invention relates to control and stabilization systems for the angular position of aircraft and can be used as a helicopter autopilot.

The purpose of the invention is to increase reliability by eliminating the mechanical system of the matching mechanism and the accuracy of control.

In FIG. Fig. 1 is a structural diagram of a helicopter autopilot; Fig. 2 is a structural diagram of an object deflector signal shaper.

A helicopter autopilot (see Fig. 1) comprises an object 1 angle sensor, a compensation sensor 2, and a driver. 3 signals of the angle of deviation of the object, driver 4 of the control pulses, the first logical element And 5, the first key b, common bus 7, the device for fetching and storing 8, differentiating element 9, the second 10 key, adder 11, the servo of the control 12, the output of which is the autopilot output. The signal generator of the deflection angle of the object 3 (Fig. 2) has demodulators 13 and 14, a reference voltage source 15, first and second switches 16 and 17, first and second analog-to-digital converters 18 and 19, having reference inputs 20, analog inputs 21, inputs Start 22, analog outputs 23 and outputs End of conversion 24, second and first logical elements AND 25 and 26, logical element OR 27, adder 28.

The autopilot operates as follows.

The angle sensor T provides a signal of the position of the object in space in the form of two AC voltages, modulated in amplitude as a function of the sine and cosine of the deflection angle. On the demodulators 13 and 14, these signals are rectified taking into account the phase voltage of the angle 1. The demodulators 13 and 14 are phase-sensitive rectifiers. The signals from the demodulators 13 and 14 are fed to the analog inputs 21 of the first 18 and second 19 analog-to-digital converters, respectively, and to the make contacts, respectively, of the second 17 and first 16 keys. In the absence of a signal at the control input of keys 16 and 17, the reference inputs 20 of the analog-to-digital converters 18 and 19 receive the reference voltage from the reference voltage source 15 through the closing contacts of the keys 16 and 17. The autopilot operates in the Control and Stabilization modes. In the Control mode, pulses of a given frequency are generated at the second output of block 4. From the second output of the driver of the control pulses 4, a sequence of pulses is fed to the inputs 22 Start analog-digital

converters 18 and 19 and to the input of the first logical element And 25. From the third output of the control pulse generator 4, short pulses disappearing at the input of the sampling and storage device 8

simultaneously with pulses at the second output of the control pulse generator 4, at the first output of which in the Control mode it is a logical zero. When a pulse arrives at the inputs 22 of analog-to-digital converters 18 and 19 (along the leading edge of the pulse), the process of converting the signals coming from demodulators 13 and 14 begins, in proportion to sin a, cos a,

relative to the voltage of the reference voltage source 15 in digital form and their subsequent storage. In this case, the values s.ln a and cos a, which took place at the time the conversion was completed, are stored. Because conversion time. Since the conversion time is very short (no more than 120 μs), the values of the signals from demodulators 13 and 14 practically do not have time to change (the angle remains the same). When the conversion is completed, outputs 24 output signals from the analog-to-digital converters 18 and 19 in the form of pulses arriving at the first and second inputs of the first logical element AND 28. When these pulses coincide, a pulse is generated at its output, which, having passed the OR gate 27, will go to the second input of the second logical element And 25,

at the first input of which at that time there will be a pulse from the second output of the driver of the control pulses 4. The second logical element AND 25 gives out a logical unit at its output; which

. will block the output of the OR gate 27 in a single state when the signals from the outputs 24 disappear. End of conversion of analog-to-digital converters 18 and 19, Output signal

logic gate OR 27 will switch the keys 16 and 17. as a result, the reference input 20 of the first analog-to-digital Converter 18 will be switched from the output of the reference source

voltage 15 to the output of the demodulator 14, and the reference input 20 of the second analog-to-digital converter 19 from the output of the reference voltage source 15 to the output of the demodulator 13. From now on, the analog-to-digital converters 18.19 will perform the functions of a multiplying digital analog converter and at their outputs signals are generated respectively a cos (a + Yes) and CQS a sin (a + Yes), where Yes is the angular mismatch. As a result of (outputting from the adder 28 output, a signal is generated: sin Yes sin a. Cds (a + Yes) - cos а sin (а + Yes), this signal is fed to the information input of the sampling and storage device 8. At the control input the sampling and storage device 8 receives a pulse from the third output of the control pulse generator. The magnitude of the signal increment at the output of the adder 28 passes through the sampling and storage device 8 and through the opening contacts of the key 10 to the second input of the adder 11 and then when the pulse disappears on the control inlet of sampling device and tem Line 8 is stored until the next pulse arrives. The first exit of the adder 11 at that time is connected to the common bus 7. At the same time, the pulse from the output of the second control pulse generator 4 also disappears, as a result of which the keys 16 and 17 return to their original position. The pulse process is repeated.At the second input of the Adder 11c of the sampling and storage device 1, a signal will be generated in the form of a certain sequence of steps in the Case of the presence of the rate of change of signals from the angle sensor 1, i.e. angular velocity of rotation of the object. If the rotation speed of the object is constant, then at the second input of the adder 11 the same signal level will be maintained, since the magnitude of the framing of the output signal for the same period of time will be constant. With a sufficient sampling frequency, a larger incremental output signal V of the sampling and storage system 8 will be proportional to the angular velocity of the object, since before each measurement the signal at the output of the adder 28 is zeroed and increments are fixed in the linear zone sinus characteristics. Thus, in the Control mode, the servo drive 12 receives the sum of the signals of the angular velocity of the object and the compensation sensor 2. In the Stabilization mode, a constant voltage is output from the first and second outputs of the control pulse generator 4 state in the form of a logical unit, at the third output - a logical zero is formed. On the leading edge of the pulse received at

input 22 Start of both analog-to-digital converters 18 and 19 when the stabilization mode is turned on, the process of converting and storing signals 5 starts, similarly as in the Control mode. Upon completion of the conversion, the output of the logical element OR 27 receives the signal in the form of a logical unit at the input of the logical element And 5, at the second input of which 10 the voltage from the first output of the control pulse generator 4 will already be present. The signal from the output of the logical element And 5 will switch the key 6 from the common bus 7 and connects the output of the adder 15 of 28 to the input of the differentiating link 9 and the first input of the adder 11. At the same time, the second input of the adder 11 will be disconnected from the output of the sampling and storage device 8 and connected to the output 0 of the differentiating link 9 using the second key, to the control input of which the signal from the first output of the control pulse generator 4 is received. From this moment, a signal proportional to 5 sin Yes, formed at the output of the adder 28, is supplied to the first input through the closing contacts of the key 6 the adder 1.1, and through the differentiating link 9 and the closing contacts of the key 10 to the second input 0 of the adder 11. Thus, in the stabilization mode, the input of the servo drive 12 receives the sum of signals proportional to the deviation of the object from the given position (Yes) and angular velocity (Yes) 5 of the object, which provide stabilization of the angular position of the object and parry short-period disturbances. The signal of the compensation sensor 2, coming through the adder 11 to the servo drive. 12. provides (0 prints signal compensation, proportional to the displaced angle of deviation of the object when the pilot intervenes in the control. Technical advantages of the proposed device compared to the prototype allow 5 to increase the reliability of the autopilot and improve the accuracy of generating the angular velocity signal, which makes it possible to improve control object.

Claims (2)

SUMMARY OF THE INVENTION 0 1. A helicopter autopilot comprising an aircraft deflection angle sensor, a compensation sensor, a differentiating element, a serially connected adder and a control actuator 5, characterized in that, in order to increase the reliability and accuracy of control, a shaper is additionally introduced into it the signal of the angle of deviation of the aircraft, the first and second inputs of which are connected respectively with the first and second outputs of the sensor of the angle of deviation of the aircraft according to the blue signals of the angle and cosine of the angle, and the device for selecting orcs and storing, the first and second keys, serially connected control pulse shaper, the second output of which is connected to the third input of the shaper of the aircraft deviation angle signal, the third output is the control input of the sampling device and storage, and the logical element And, the second input of which is connected to the second output of the driver of the signal signal of the angle of deviation of the aircraft, and the output is with the control input of the first key, the first output of the driver of the signal of angle o the rotational direction of the aircraft is connected to the input of the differentiator link and the first input of the adder through the make contacts of the first key, the NC contact of which is connected to the common power bus, the output of the differentiator link is connected to the second input of the adder through the make contacts of the second key, the make contact of which is connected to the output of the sampling device and storage, and the control input is with the first output of the control pulse generator, the output of the compensation sensor is connected to the third input of the adder. 2. The autopilot according to claim 1, with the proviso that the drone of the aircraft deflection angle is made in the form of series-connected first demodulator, first analog-to-digital converter and adder, the output of which is first exit driver of the signal of the angle of deviation of the aircraft, serially connected to the first logical element AND and the logical element OR, the output of which is the second output of the signal generator of the signal of the angle of deviation of the aircraft, serially connected to the second demodulator and the second analog-to-digital converter, the output of which is connected to the second inverse input the adder, the first and second keys, the source of the reference voltage, the output of which is connected to the reference inputs of the first and second analog front-panel converters, respectively, through the disconnecting contacts of the first and second keys, the second logical element And, the first input of which is connected to the inputs; The start of the first and second analog-to-digital converters and is the third input of the signal generator - the angle of deviation of the aircraft; the second input is connected to the output logical element OR and control inputs of the first and second keys, and the output is with the second input of the OR gate, the output of the first demodulator is connected to the make contact of the second key, the output of the second demodulator is with the make contact of the first key, the second outputs of the first and second analog-to-digital converters by signal The end of the conversion is connected respectively to the first and second inputs of the first logical element And, the inputs of the first and second demodulators are respectively the first and second inputs of the drift angle signal of the aircraft. , FIG. 2