RU2465558C1 - Apparatus for determining aircraft mass - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: apparatus for determining aircraft mass has series-connected piezoelectric pressure sensors fitted at points where the landing gear unit is mounted, a processor and a display device in the crew cabin. The apparatus also includes a transmitting device, an AND element, two signal selectors, an altitude sensor and a dispatcher receiving channel, which consists of a receiving device, an OR element, a display and a memory unit.

EFFECT: higher flight safety.

2 cl, 3 dwg

Description

The invention relates to aircraft, in particular to on-board computer information systems of the aircraft, and can be used to determine the mass of the aircraft.

Closest to the invention is a device for determining the mass of an aircraft, which consists of series-connected pressure sensors, a processor and a display device in the cockpit, the processor made in the form of a microcontroller, the display device in the cockpit made in the form of a display, pressure sensors made in the form of piezoelectric sensors and are located in the places of attachment of the landing gear with the design of the aircraft, while in the pressure sensors when exposed to the mass of the flying signals are formed in the form of electromotive forces (EMF), which are transmitted to the microcontroller, where they are converted into numerical values of the mass of the aircraft and the position of its center of mass relative to the longitudinal and transverse axes, and then these signals are transmitted to the cockpit to a display device made in a display that displays information about the mass of the aircraft and the position of its center of mass before take-off, as well as the issuance of a signal to prohibit the departure of the aircraft in case the current the beginning of the mass of the aircraft is greater than the permissible value and the position of its center of mass before take-off does not correspond to the permissible values [1].

The disadvantage of this device is the lack of control by the mass controller of the aircraft during takeoff.

The technical result of the invention is to improve flight safety due to additional control of the mass of the cargo of the aircraft by the dispatcher.

The technical result of the invention is achieved by the fact that in the device for determining the mass of the aircraft, which consists of series-connected pressure sensors, a processor and a display device in the cockpit, the processor is made in the form of a microcontroller, the display device in the cockpit is made in the form of a display, pressure sensors are made in the form of piezoelectric sensors and are located in the places of attachment of the landing gear with the design of the aircraft, while in the pressure sensors when acting on to them, the masses of the aircraft form signals in the form of electromotive forces (EMF), which are transmitted to the microcontroller, where they are converted into numerical values of the mass of the aircraft and the position of its center of mass relative to the longitudinal and transverse axes, and then these signals are transmitted to the cockpit to the display device, made in the form of a display on which information is displayed on the mass of the aircraft and the position of its center of mass before take-off, as well as on the issuance of a departure prohibition signal if the current value is e the mass of the aircraft is greater than the permissible value and the position of its center of mass before takeoff does not correspond to the permissible values, an additional memory block, a transmitting device, an AND element, a first and second signal setter, an OR element, a receiving channel of a dispatcher are introduced, while the output of the microcontroller is connected to the first the input of the memory unit, the first input of the OR element, the second and third inputs of which are connected respectively to the outputs of the first and second signal setters, and the output is connected to the input of the transmitting device, in The second input of the memory unit is connected to the output of the And element, the first and second inputs of which are connected to the output of the height sensor and the output of the second master, the output of the transmitting device via a contactless line connected to the input of the receiving channel of the dispatcher, which consists of a receiving device, an OR element, a display, and a memory unit, while the outputs of the receiving device are connected to the inputs of the OR element, the output of which is connected to the inputs of the display and the memory unit.

New elements with significant differences in the device are the memory unit, the first and second signal generators, the AND element, the OR element, the transmitting device and the receiving communication channel between known and new elements.

The invention is illustrated by drawings.

Figure 1 presents a diagram of the action of forces on an aircraft when it is on the ground. Figure 2 is a structural diagram of a device for determining the mass of the aircraft. Figure 3 - structural diagram of the receiving channel of the dispatcher.

The aircraft (Fig. 1) has gravity G applied at its center of mass (CM). The center of mass is located inside the fuselage 1. From the bottom to the fuselage are the landing gear: the main struts 2 and 3 and the front strut 4. Gravity G is balanced by the reactions from the ground acting on the main struts N _Ch. and front strut N _lane. . The reaction to the main racks consists of two components: acting on the left main rack N _hl and on the right main strut H _gl.pr. .

On each landing gear, between the fuselage and the strut, pressure sensors 5, 6 and 7 are installed, for example piezoelectric sensors. When pressure is _applied to them, they generate signals With _h. , With _h.pr. and C _lane respectively, from sensors on the main left, on the main right and on the front struts in the form of voltage (EMF). The chassis base (the distance between the axles of the wheels of the main struts and the axis of the front wheel) is denoted by L. The distance from the center of mass to the axles of the wheels of the main struts is denoted by l ₁ , and to the axis of the front wheel by l ₂ . The gauge (the distance between the axes of the main struts) is indicated by "a" (type A, figure 1). The distance from the center of mass to the axis of the main left pillar is indicated by "a ₁ ", and to the axis of the main right pillar - by "a ₂ ".

In _figure 2, pressure sensors 5, 6 and 7 are denoted by D _h.pr. , D. _gl. and D _per. sensors respectively on the main right and left on the main front racks, from which receives signals respectively C _gl.pr. , With _hl and C _lane .

The device for determining the mass of the aircraft contains the first 5, second 6 and third 7 sensors, a microcontroller 8, a display 9, a memory unit 10, a transmitting device 11, an element 12, the first 13 and second 14 signal adjusters, a matching device 15, a receiving channel 16 dispatcher, while the outputs of the first 5, second 6 and third 7 sensors are connected respectively to the first, second and third inputs of the microcontroller 8, the output of which is connected to the input of the display 9, the first input of the memory unit 10, the first input of the OR element 15, the second and third inputs whose are connected respectively to the outputs of the first 13 and second 14 signal sources, and the output is connected to the input of the transmitting device 11, the second input of the memory unit 10 is connected to the output of the element And 12, the first and second inputs of which are connected to the output of the height sensor and the output of the second 14 of the controller, output the transmitting device is contactlessly connected to the receiving channel 16 of the controller, which consists of a receiving device 17, an OR element 18, a display 19 and a memory unit 20, while the outputs of the receiving device 17 are connected to the inputs of the OR element 18, the output to It is connected to the inputs of the display 19 and the memory unit 20.

The device operates as follows.

On the ground, when the aircraft does not move, then the sum of the projections of all the forces on each of the coordinate axes and the sum of their moments relative to these axes are zero [3]. The projections of the forces acting on the aircraft will only be on the U axis. On the other axes, these projections will be zero. The sum of the projections of the forces on the Y axis corresponds to the expression:

Σ _Fiy = 0; N _Ch. + N _per. -G = 0;

N _Ch. = N _gl. + N _gl.

Then N _Ch. + N _gl. + N _per. -G = 0.

Or

Thus, the mass G of the aircraft is determined in accordance with the expression (1).

The moments will act only with respect to the X and Z axes, and with respect to the Y axis they will be equal to zero.

The sum of the moments relative to the X axis is determined in accordance with the expression:

Σm _x = 0; -N _hl · _A1 + N _gl.pr. A ₂ = 0

From here

The distance “a” is known (track gauge).

Then a ₂ = aa ₁ .

Substitute in (2) and get:

N _gl. (aa ₁ ) = N _gl. A ₁ .

Or N _Ch. A-N _gl. A ₁ = N _hl A ₁ .

Or N _{Ch. Aa 1} (N _gl . _Apr. + N _gl . _L. ).

Or N _Ch. · A = a ₁ · N _Ch. .

From here

Those. the position of the center of mass in the transverse direction is determined by the formula (3).

The sum of the moments relative to the Z axis is determined as follows:

Σ _mz = 0; -N _ch. L ₁ + N _per. L ₂ = 0;

From here

The chassis base L is known. Then l ₂ = Ll ₁ .

Substitute in (4) and get:

N _lane (Ll ₁ ) = N _Ch. L ₁ .

Or N _per. · LN _per. · L ₁ = N _gl. L ₁ .

Or N _per. L = l ₁ (N _lane + N _gl. ).

From here

Equation (5) determines the position of the center of mass in the longitudinal direction of the aircraft.

Thus, using equation (1), the mass of the aircraft M (gravity G) is determined. Values of the reactions M _gl. , N _gl. and N _per. determined by the magnitude of the signals (EMF) With _hl , With _h.pr. and C _lane with pressure sensors 5, 6 and 7. This mass should be less than or equal to its limit value M _before. (G _prev. ), I.e. M≤M _prev. (G <G _prev. ) Or N _gl. + N _gl. + N _per. ≤G _prev . The value of G _prev. for each aircraft is known.

Equation (5) determines the position of the center of mass along the longitudinal axis of the aircraft. The value of l ₁ must be less than L, i.e. l ₁ <L. If the position of the center of mass extends beyond the base of the chassis, then longitudinal stability is violated during take-off.

Equation (3) determines the position of the center of mass in the transverse direction. It is desirable that the value of "a ₁ " be close to half the value of "a", i.e.

otherwise roll appears.

The device operates as follows. As the pressure sensors 5, 6 and 7 (D _{gl.pr., gl.l.} D, L _per.) Shot signals (EMF) C _gl.pr. , With _hl and C _lane (Fig.2), proportional to the forces acting on these sensors (proportionally to N _gl.pr. , N _gl.l. and N _per. ), which are proportional to the mass of the aircraft (its gravity): the greater the mass of the aircraft, the more signals With _h.pr. , With _hl , With _per. . These signals are fed to the microcontroller 8, which converts them to the signals "mass of the aircraft M", "Center of mass l ₁ " (position of the center of mass on the longitudinal axis of the aircraft), "Center of mass a ₁ " (position of the center of mass on the transverse axis of the aircraft ) according to the following algorithm.

1. Each signal With _h.pr. , With _hl , With _per. converted to mass m ₁ , m ₂ , m _3, respectively.

2. All masses are summed, forming the mass of the aircraft M = m ₁ + m ₂ + m ₃ + m _w , where m _w is the mass of all landing gear (it is known in advance).

3. A signal “Aircraft mass M” is generated and is fed to a display 9 located in the cockpit. If M> M is permissible, then it is forbidden to fly out with such a mass. The red signal lights up on the display - departure is prohibited.

4. Formula (5) is converted to the formula:

5. The signal "Center of mass l ₁ " is generated and served on the display 9, located in the cockpit.

If l ₁ <L, then l _{1 is} displayed in green.

с точки зрения продольной устойчивости летательного аппарата на разбеге (и пробеге, если посадка с грузом), т.е.

.Most favorable value

from the point of view of the longitudinal stability of the aircraft on take-off run (and mileage if landing with a load), i.e.

.

If l ₁ is close to 0.1 L or less or 0.9 L or more, then the crew should pay special attention to the possibility of departure with such an arrangement of the center of mass or increased attention to control in these modes. If l ₁ ≤0 · L or l ₁ > L, then a departure with such an arrangement of the center of mass is impossible: the probability of a catastrophe is very high. The red signal lights up on the display - departure is prohibited.

6. Formula (3) is converted to the formula:

7. The signal "Center of mass a ₁ " is generated and fed to the display 9, located in the cockpit.

, т.е. центр масс находится в плоскости, продольной оси летательного аппарата, и крена в этом случае не будет при отрыве летательного аппарата от земли. Если a₁<0·a или a₁>a, то вылет с таким расположением центра масс запрещается, так как случайное попадание одной из стоек шасси в яму или на бугорок может накренить летательный аппарат на разбеге и привести к катастрофе. Если 0,5a<a ₁<0,5a, то летчик должен быть готов парировать крен при отрыве летательного аппарата от земли.The most favorable position of the center of mass when

, i.e. the center of mass is in the plane of the longitudinal axis of the aircraft, and there will be no roll in this case when the aircraft is off the ground. If a ₁ <0 · a or a ₁ > a, then departure with such an arrangement of the center of mass is prohibited, since an accidental hit of one of the landing gears in a pit or on a hill can cause the aircraft to bank on the take-off run and lead to disaster. If 0, 5a < a ₁ <0,5 a , then the pilot should be ready to fend off the roll when the aircraft is off the ground.

If a ₁ <0 · a and a ₁ > a, a red signal lights up on display 9 - departure is prohibited.

Thus, before departure, the pilot presses the corresponding button on the display to find out the mass of the aircraft and the location of its center of mass. If M> M is permissible, l ₁ ≤0 · L or l ₁ ≥L, a ₁ <0 · a or a ₁ > a, then the red signal lights up on the display (for which of the above reasons, the pilot will determine by the numerical value of M, l ₁ , a ₁ ). In other cases, the values of these quantities are displayed in a different (not red) color, and the pilot, being in the cockpit of the aircraft, receives this information. Information about the mass of the aircraft and the location of the center of mass is additionally received in the memory unit 10 and through the OR element to the input of the transmitting device 11.

The transmitting device 11 provides the transmission of information about the number of the aircraft, its mass and the location of its center of mass, about the transmission time to the dispatcher.

The first 13 signal generator generates a signal corresponding to the number of the aircraft, and the second 14 generator generates a signal corresponding to the time of information transmission, these signals are fed to the second and third inputs of the OR element 15, the first input of which receives a signal corresponding to the mass and location of its center of mass .

The receiving device 17 receives these signals and through the element OR 18 transmits them to the display 19 and to the memory unit 20 for storage.

The dispatcher, depending on this information, makes a decision to ban or allow the take-off of the aircraft.

In addition, in block 10 of the memory is the summation of the transported cargo and the fixation of the take-off time of the aircraft.

When the aircraft takes off from the height sensor, the signal enters the first input of the And 12 element, the second input of which receives the signal from the output of the second 14 of the master. From the output of the element And 12, the signal goes to the second input of the memory unit 10.

Thus, the flight safety is improved due to additional control by the mass dispatcher and cargo centering.

Information sources

1. RF patent No. 2400405, dated September 27, 2010

3. Targ S.M. Short course of theoretical mechanics. - M .: Nauka, 1970 .-- p.117.

4. Yavorsky B.M., Seleznev Yu.A. A reference guide to physics for applicants to universities and for self-education. - M .: Nauka, 1989 .-- S. 42, 51-53.

Claims (2)

1. The device for determining the mass of the aircraft contains series-connected pressure sensors, a processor and a display device in the cockpit, and the processor is made in the form of a microcontroller, the display device in the cockpit is made in the form of a display, pressure sensors are made in the form of piezoelectric sensors and placed in places mounting the landing gear with the design of the aircraft, while in the pressure sensors when exposed to the mass of the aircraft, signals are generated in the form of an electric driving forces (EMF), which enter the microcontroller, where they are converted into numerical values of the mass of the aircraft and the position of its center of mass relative to the longitudinal and transverse axes, and then these signals are transmitted to the cockpit on a display device made in the form of a display on which information about the mass of the aircraft and the position of its center of mass before takeoff, and the prohibition of departure if the current value of the mass of the aircraft is greater than the permissible value and the position of its center of mass Red take-off does not correspond to permissible values, characterized in that a memory block, a transmitting device, an AND element, a first and second signal pickups, an OR element, a dispatcher receiving channel are inserted, while the output of the microcontroller is connected to the first input of the memory unit, the first input of the OR element, the second and third inputs of which are connected respectively to the outputs of the first and second signal setters, and the output is connected to the input of the transmitting device, the second input of the memory unit is connected to the output of the And element, the first and second inputs of which o connected to the output of the height sensor and the output of the second signal generator, the output of the transmitting device via a contactless line is connected to the input of the receiving channel of the dispatcher, which consists of a receiving device, an OR element, a display and a memory unit, while the outputs of the receiving device are connected to the inputs of the OR element whose output is connected to the inputs of the display and the memory unit. 2. The device for determining the mass of the aircraft according to claim 1, characterized in that the microcontroller’s functioning algorithm consists in converting the signals from the outputs of the pressure sensors C _gl.pr , C _gl.l , C _per microcontroller, respectively, into signals m ₁ , m ₂ , m ₃ , determination of the mass of the aircraft is based on the summation of all mass values M = m ₁ + m ₂ + m ₃ + m _w , where m _w is the mass of all landing gear, the position of the center of mass relative to the longitudinal and transverse axes of the aircraft, the formation of the signal "Mass flyer apparatus M ”and displaying it on the display located in the cockpit, comparing the current mass of the aircraft with an acceptable value, issuing a departure prohibition signal for M> M acceptable, determining the coordinate of the center of mass along the longitudinal axis of the aircraft in accordance with the expression

where L is the base of the aircraft chassis, generating the signal “Center of mass l ₁ ” and issuing it to the display located in the cockpit, comparing the obtained value with the value of L, issuing recommendations to the crew about the possibility of take-off, provided that the position of the center of mass along the longitudinal axis less than the chassis base of the aircraft l ₁ <L, while the position of the center of mass of the aircraft is optimal in the case of

, the value l _{1 is} displayed on the green color, if l ₁ is close to 0.1 L or less or 0.9 L or more, the crew should pay special attention to the possibility of a departure with such an arrangement of the center of mass or increased attention to control on In these modes, issuing recommendations to the pilot is prohibited if l ₁ ≤0 or l ₁ > L, the color red lights up on the display, determining the coordinates of the center of mass along the transverse axis of the aircraft in accordance with the expression

where a is the track of the aircraft chassis, generating the signal “Center of mass a ₁ ” and displaying it on the display located in the cockpit, comparing the obtained coordinate with the value a, issuing recommendations to the pilot about the possibility of take-off provided that a ₁ <a and the display shows the value of a _{1 is} green, while the value of the position of the center of mass along the transverse axis is most optimal provided

if 0,5a <a ₁ <0,5a, the pilot should be ready to fend off the roll by tearing off the aircraft by the pilot zemli, issuing recommendations on the impossibility vzleta, if a <0·a ₁ or a _1> a, and the display lights up Red color.

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