CN101774336B - Coupling communicator used for real-time monitoring system of tire pressure of airplane - Google Patents
Coupling communicator used for real-time monitoring system of tire pressure of airplane Download PDFInfo
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- CN101774336B CN101774336B CN2010100135655A CN201010013565A CN101774336B CN 101774336 B CN101774336 B CN 101774336B CN 2010100135655 A CN2010100135655 A CN 2010100135655A CN 201010013565 A CN201010013565 A CN 201010013565A CN 101774336 B CN101774336 B CN 101774336B
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- control module
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- controlled oscillator
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Abstract
The invention discloses a coupling communicator used for a real-time monitoring system of the tire pressure of an airplane. A CPU of a control module in an undercarriage is connected with a modulation unit of the control module and a demodulation unit of the control module, the modulation unit of the control module is used for carrying out FSK modulation on a digital signal, the demodulation unit of the control module is used for demodulating an FSK modulation signal, and the modulation unit of the control module and the demodulation unit of the control module are connected with a primary winding of a rotary transformer; and a CPU of a monitoring module in an airplane wheel is connected with a modulation unit of the monitoring module and a demodulation unit of the monitoring module, the modulation unit of the monitoring module is used for carrying out FSK modulation on a digital signal, the demodulation unit of the control module is used for demodulating an FSK modulation signal, and the modulation unit of the monitoring module and the demodulation unit of the monitoring module are connected with a secondary winding of the rotary transformer. The invention can be applied in a hostile environment on the airplane and is easy to meet the requirement of electromagnetic compatibility on the airplane.
Description
Technical field
The present invention relates to a kind of communicator, the magslip coupling communicator in especially a kind of aircraft tire pressure real-time monitoring system.
Background technology
Aircraft tire pressure real-time monitoring system is that a kind of air pressure to inside tires is monitored, the actual pressure of tire is provided to crew or service personnel by data bus and telltale, can alarm the pressure anomaly of tire, and the device that can regulate and control aircraft tyre pressure according to driver command, it is a up-to-date technology that guarantees aircraft safety.In daily attention, this system also can remove from tire pressure is carried out the ground artificial measurement, alleviates the maintenance workload to tire.
In the aircraft tire pressure real-time monitoring system in the wheel monitoring modular be positioned on the wheel with the wheel high speed revolution, work under bad environment need be born harsh conditions such as high low temperature, the salt air corrosion of aqueous vapor burn into, sand and dust, strong vibration, big centnifugal force.Alighting gear inner control module is installed on the undercarriage leg, and monitoring modular communicates in needs and the wheel, but the two can not carry out wired connection, so its reliable communication is a technical barrier.
Communication between slewing and the fixed equipment at present has following several method: 1) adopt slip ring communication; 2) adopt photoelectric communication; 3) adopt technology for radio frequency communication.
Slip ring belongs to slide and electrically contacts category, be to realize the most frequently used a kind of method of communicating by letter between slewing and fixed equipment, but in aircraft tire pressure real-time monitoring system, effects limit such as friction, vibrations, contact sparking and carbon distribution its application.
Photoelectricity transmission is with the carrier wave of light wave as data transmission, comprises infrared light, visible light and ultraviolet light.Because light is subject to the shelter influence, photoelectricity transmission is abominable at environment, the occasion of vulnerable to pollution is difficult to use.
At present, the monitoring automobile tyre pressure technical development is rapid, and it is to adopt technology for radio frequency to communicate, and publication number is the patent " tire pressure monitor and its antenna " of CN 1500662A, has just described a kind of like this technology.The article " research of aircraft tyre pressure monitoring system " that is published in " computer measurement and control " is the technical secondary development of carrying out of the automotive tyre pressure monitoring systems technology scheme that provides in Freescale company, also is the technology for radio frequency that adopts.But, technology for radio frequency is to make the data communication technology of carrier wave with radiowave, its electromagnetic carrier is in the radio-frequency range in the electromagnetic spectrum, have bigger communication bandwidth, very strong penetrating capacity, transmission distance far away, this can cause interference to other equipment on the aircraft, is difficult to satisfy electromagnetic compatibility requirement harsh on the aircraft.
Summary of the invention
In order to overcome the deficiency that prior art can not effectively be used in aircraft tire pressure real-time monitoring system, the invention provides a kind of magslip coupling communicator, rugged environment uses down aboard, and satisfies electromagnetic compatibility requirement harsh on the aircraft.
The technical solution adopted for the present invention to solve the technical problems is: comprise control module part, magslip and monitoring modular part.Wherein control module partly comprises alighting gear inner control module CPU, control module modulating unit, control module demodulating unit and control module coupling capacitance; Monitoring modular partly comprises monitoring modular CPU in monitoring modular modulating unit, monitoring modular coupling capacitance, monitoring modular demodulating unit and the wheel.Alighting gear inner control module CPU link control module modulating unit and control module demodulating unit, the control module modulating unit carries out the FSK modulation to the digital signal of alighting gear inner control module CPU, the control module demodulating unit restores digital signal and exports alighting gear inner control module CPU to the fsk modulated signal demodulation of input; The two ends of two mouth direct connections of control module modulating unit magslip primary winding, one end of an input end direct connection of control module demodulating unit magslip primary winding, another input end connect the other end of magslip primary winding by the control module coupling capacitance; Monitoring modular CPU connects monitoring modular modulating unit and monitoring modular demodulating unit in the wheel, the monitoring modular modulating unit carries out the FSK modulation to the digital signal of monitoring modular CPU in the wheel, the monitoring modular demodulating unit restores digital signal and exports monitoring modular CPU in the wheel to the fsk modulated signal demodulation of input; The two ends of two mouth direct connections of monitoring modular modulating unit magslip secondary winding; One end of an input end direct connection of monitoring modular demodulating unit magslip secondary winding, another input end connect the other end of magslip secondary winding by the monitoring modular coupling capacitance
Apparatus of the present invention adopt frequency shift keying modulation system (FSK), and the carrier amplitude of FSK is constant, and frequency is a variable, by binary digital information control carrier frequency, carrier frequency are changed with the variation of binary message.Because binary digital information only comprises two kinds of different symbols, so modulation signal has two different frequency f
1And f
2, f
1Corresponding numerical information " 1 ", f
2Corresponding numerical information " 0 ".
Described control module modulating unit comprises first voltage controlled oscillator VCO 1, second voltage controlled oscillator VCO 2, data selector and driving circuit.The output of first voltage controlled oscillator VCO 1 and second voltage controlled oscillator VCO 2 is as two inputs of data selector, treat that modulated digital signal passes through data selector, select to represent respectively first voltage controlled oscillator VCO, 1 signal or second voltage controlled oscillator VCO, 2 signals of numeral " 1 " and " 0 ", by driving circuit driven in rotation voltage transformer, the information of carrying out sends.
Described first voltage controlled oscillator VCO 1 and second voltage controlled oscillator VCO, 2 output signal frequencies are respectively 25kHz and 100kHz.
Described monitoring modular modulating unit has and the identical structure and parameter of control module modulating unit.
The communication baud rate of apparatus of the present invention needs less than 2500bps.
The control module demodulating unit comprises the first phase demodulator PD1, the second phase demodulator PD2, filter capacitor C
1And C
2, operational amplifier A MP, pull-up resistor R
L, voltage controlled oscillator VCO, timing resistor R
TWith timing capacitor C
TSignals of rotating transformer is applied to the input end of the first phase demodulator PD1 and the second phase demodulator PD2 respectively through the control module coupling capacitance, and the output of the first phase demodulator PD1 is through filter capacitor C
2Give voltage controlled oscillator VCO after the filtering, the second phase demodulator PD2 is given in the output of voltage controlled oscillator VCO then, and the output of the second phase demodulator PD2 is through filter capacitor C
1Filtering, operational amplifier A MP amplify and pull-up resistor R
LOn just can get digital signal after the demodulation after drawing.Timing resistor R
TWith timing capacitor C
TBe used to cooperate the required frequency signal of generation voltage controlled oscillator VCO.
Described monitoring modular demodulating unit has and the identical structure and parameter of control module demodulating unit.
Apparatus of the present invention are by the magslip coupled communication, realization be a kind of half-duplex operation method.When alighting gear inner control module monitoring modular in wheel sends information, alighting gear inner control module CPU is by the control module modulating unit, digital signal is converted into high-frequency sasser and the driven in rotation voltage transformer of representing digital " 0 " and " 1 ", the monitoring modular demodulating unit carries out demodulation to the high-frequency sasser that the monitoring modular coupling capacitance is coupled to, after send that monitoring modular CPU handles in the wheel; When monitoring modular in the wheel when alighting gear inner control module sends information, monitoring modular CPU is by the monitoring modular modulating unit in the wheel, digital signal is converted into high-frequency sasser and the driven in rotation voltage transformer of representing digital " 0 " and " 1 ", the control module demodulating unit carries out demodulation to the high-frequency sasser that the control module coupling capacitance is coupled to, after send alighting gear inner control module CPU to handle.
The invention has the beneficial effects as follows: apparatus of the present invention are applied in the aircraft tire pressure real-time monitoring system to compare with the traditional communication method and have the following advantages: 1) apparatus of the present invention utilize magslip to communicate, the induction coupling magnetic circuit of traditional transformer is separated, just, secondary winding is wound in respectively on the stator core and rotor core that can rotate mutually, the realization fixed equipment is communicated by letter with the no touch electromagnetic coupled between slewing, therefore, no any contact between the communicating pair, electric insulating to each other, there is not bare exposed conductor to exist, there are not mechanical friction and wearing and tearing, electro spark can not take place yet.And communication media---magnetic field is insensitive to dust, dirt etc., can not influence communication quality, and rugged environment is used down aboard; 2) communication means of apparatus of the present invention realization and common radiocommunication mode are distinguishing, and the latter communicates by letter at a distance by electromagnetic wave propagation, and its signal strength easily externally forms radiation with square decay of distance, causes interference; The former then is the short range transmission that realizes signal by electromagnetic coupled, communication media---magnetic field almost is completely restricted in magslip stator core and rotor core, its signal strength of leakage part seldom is with cube decay rapidly of distance, the interference that externally causes is little, by suitable shielding, can stop the radiated interference that it externally causes fully, electromagnetic compatibility requirement on the aircraft that is content with very little.
The present invention is further described below in conjunction with drawings and Examples.
Description of drawings
Fig. 1 is a magslip coupled communication system architecture.
Among the figure, 1-alighting gear inner control module CPU, 2-control module modulating unit, 3-control module demodulating unit, 4-control module coupling capacitance, 5-magslip, 6-monitoring modular modulating unit, 7-monitoring modular coupling capacitance, monitoring modular CPU in the 8-monitoring modular demodulating unit, 9-wheel.
Control signal and high-frequency ac pulse concerned scheme drawing when Fig. 2 modulated for FSK.
Fig. 3 is a control module modulating unit constructional drawing.
Among the figure, 10-first voltage controlled oscillator (VCO), 11-second voltage controlled oscillator (VCO), 12-data selector, 13-driving circuit.
Fig. 4 is a control module demodulating unit constructional drawing.
Among the figure, 14-first phase demodulator, 15-second phase demodulator, 16-op amp, 17-voltage controlled oscillator (VCO).
The specific embodiment
As shown in Figure 1, the present invention includes the control module part, magslip 5 and monitoring modular part.Wherein control module partly comprises alighting gear inner control module CPU 1, control module modulating unit 2, control module demodulating unit 3, control module coupling capacitance 4; Monitoring modular partly comprises monitoring modular CPU 9 in monitoring modular modulating unit 6, monitoring modular coupling capacitance 7, monitoring modular demodulating unit 8 and the wheel.Alighting gear inner control module CPU 1 link control module modulating unit 2 and control module demodulating unit 3, control module modulating unit 2 is used for digital signal is carried out the FSK modulation, control module demodulating unit 3 is used for the fsk modulated signal demodulation is restored digital signal.2 two mouth direct connections of control module modulating unit magslip, 5 primary windings, 3 one input end direct connections of control module demodulating unit magslip, 5 primary windings, another input end connects magslip 5 primary windings by control module coupling capacitance 4.Monitoring modular CPU 9 connects monitoring modular modulating unit 6 and monitoring modular demodulating unit 8 in the wheel, and monitoring modular modulating unit 6 is used for digital signal is carried out the FSK modulation, and monitoring modular demodulating unit 8 is used for the fsk modulated signal demodulation is restored digital signal.6 two mouth direct connections of monitoring modular modulating unit magslip, 5 secondary winding.8 one input end direct connections of monitoring modular demodulating unit magslip, 5 secondary winding, another input end connects magslip 5 secondary winding by monitoring modular coupling capacitance 7.
The invention process instance communications is half-duplex operation.When alighting gear inner control module monitoring modular in wheel sends information, alighting gear inner control module CPU 1 is by control module modulating unit 2, digital signal is converted into high-frequency sasser and the driven in rotation voltage transformer 5 of representing digital " 0 " and " 1 ", the high-frequency sasser that 8 pairs of monitoring modular coupling capacitances 7 of monitoring modular demodulating unit are coupled to carries out demodulation, after send that monitoring modular CPU 9 handles in the wheel; When monitoring modular in the wheel when alighting gear inner control module sends information, monitoring modular CPU 9 is by monitoring modular modulating unit 6 in the wheel, digital signal is converted into high-frequency sasser and the driven in rotation voltage transformer 5 of representing digital " 0 " and " 1 ", the high-frequency sasser that 3 pairs of control module coupling capacitances 4 of control module demodulating unit are coupled to carries out demodulation, after send alighting gear inner control module CPU 1 to handle.
With reference to Fig. 2, the invention process example adopts frequency shift keying modulation system (FSK), and the carrier amplitude of FSK is constant, and frequency is a variable, by binary digital information control carrier frequency, carrier frequency is changed with the variation of binary message.Because binary digital information only comprises two kinds of different symbols, so modulation signal has two different frequency f
1And f
2, f
1Corresponding numerical information " 1 ", apparatus of the present invention adopt 25kHz, f
2Corresponding numerical information " 0 ", apparatus of the present invention adopt 100kHz.
With reference to Fig. 3, control module modulating unit 2 comprises first voltage controlled oscillator (VCO) (VCO1) 10, second voltage controlled oscillator (VCO) (VCO2) 11, data selector 12 and driving circuit 13.The output frequency of first voltage controlled oscillator (VCO) (VCO1) 10 and second voltage controlled oscillator (VCO) (VCO2) 11 is respectively two inputs of the carrier signal of f1 and f2 as data selector, treat that modulated digital signal selects represent respectively first voltage controlled oscillator (VCO) (VCO1) 10 of digital " 1 " and " 0 " and the signal of second voltage controlled oscillator (VCO) (VCO2) 11 by data selector, by driving circuit 13 driven in rotation voltage transformers 5, the information of carrying out sends.
In this embodiment, first voltage controlled oscillator (VCO) (VCO1) 10 and second voltage controlled oscillator (VCO) (VCO2), 11 output signal frequencies are respectively 25kHz and 100kHz.
Described monitoring modular modulating unit 6 has and control module modulating unit 2 identical structure and parameters.
The communication baud rate of the invention process example is got 1200bps.
With reference to Fig. 4 control module demodulating unit constructional drawing, received signal enters demodulating unit (comprising control module demodulating unit 3 and monitoring modular demodulating unit 8) by capacitive coupling.Demodulating unit inside has comprised two phase demodulator PD1 14 and unit such as PD215, amplifier AMP 16, voltage controlled oscillator VCO 17.Phase demodulator PD1 14 and PD2 15 all adopt two balance simulation multiplier circuits, and under input small-signal situation (about tens mV), it is output as sinusoidal phase characteristic, and under the input large-signal conditions (more than the hundreds of mV), its output changes linear phase characteristic into.The phase-locked loop output signal produces the frequency of free oscillations of voltage controlled oscillator (VCO) 17 and external timing element R by voltage controlled oscillator VCO 17
T, C
TRelational expression be:
Above-mentioned R
T, C
TFor being used for cooperating the timing element that produces voltage controlled oscillator (VCO) (VCO) 17 required frequency signals, this embodiment f
o=25kHz, according to following formula, R
T, C
TMultiple combination is arranged, and a kind of feasible following the example of is: R
TGet 10k Ω, C
TGet 0.01 μ F.
During circuit working, incoming signal in phase demodulator PD1 14 with the output signal phase demodulation of VCO 17, phase difference signal becomes and differs proportional voltage signal after filter circuit filtering, is used to control VCO 17 output frequency f
oThe tracking phase of input signals changes.If frequency input signal drops in the pull-in range of phase-locked loop, loop-locking then when the oscillator output frequency is identical with incoming frequency, has only phase difference between the two and does not have difference on the frequency.
The mode of operation of phase demodulator PD2 15 is slightly different with phase demodulator PD1 14, and it is the signal f that utilizes voltage controlled oscillator (VCO) (VCO) 17 outputs
oCarrying out phase demodulation with incoming signal again after 90 ° of phase shifts, is a quadrature phase detector.Under the loop-locking situation, two incoming signals of PD2 15 differ on phase place and are about 90 °, thereby the output voltage of PD2 15 reaches the maxim in its output area, and are anti-phase through operational amplifier A MP 16 again, in low level of its mouth output.The mouth of operational amplifier A MP 16 is the open-drain way of output, can absorb the outgoing current of maximum 100mA during low level output.The low-level output signal of this port can be converted to voltage signal to be complementary with TTL or CMOS interface circuit by pull-up resistor.
Its overall work characteristic is: when signal input part adding amplitude is that AC signal and frequency more than the 20mV falls into (f
o± when BW) scope was interior, low level detection signal of mouth output utilized this characteristic, realizes the fsk signal demodulation.
The monitoring modular demodulating unit 8 of this embodiment has and control module demodulating unit 3 identical structure and parameters.
Claims (6)
1. coupling communicator that is used for aircraft tire pressure real-time monitoring system, comprise the control module part, magslip and monitoring modular part is characterized in that: control module partly comprises alighting gear inner control module CPU, control module modulating unit, control module demodulating unit and control module coupling capacitance; Monitoring modular partly comprises monitoring modular CPU in monitoring modular modulating unit, monitoring modular coupling capacitance, monitoring modular demodulating unit and the wheel; The control module modulating unit carries out the FSK modulation to the digital signal of alighting gear inner control module CPU and obtains fsk modulated signal one, and the control module demodulating unit restores digital signal and exports alighting gear inner control module CPU to fsk modulated signal one demodulation of input; The two ends of two mouth direct connections of control module modulating unit magslip primary winding, one end of an input end direct connection of control module demodulating unit magslip primary winding, another input end connect the other end of magslip primary winding by the control module coupling capacitance; The monitoring modular modulating unit carries out FSK modulation fsk modulated signal two to the digital signal of monitoring modular CPU in the wheel, and the monitoring modular demodulating unit restores digital signal and exports monitoring modular CPU in the wheel to fsk modulated signal two demodulation of input; The two ends of two mouth direct connections of monitoring modular modulating unit magslip secondary winding; One end of an input end direct connection of monitoring modular demodulating unit magslip secondary winding, another input end connect the other end of magslip secondary winding by the monitoring modular coupling capacitance.
2. a kind of coupling communicator that is used for aircraft tire pressure real-time monitoring system according to claim 1 is characterized in that: described control module modulating unit comprises first voltage controlled oscillator VCO 1, second voltage controlled oscillator VCO 2, data selector and driving circuit; The output of first voltage controlled oscillator VCO 1 and second voltage controlled oscillator VCO 2 is as two inputs of data selector, data selector selects first voltage controlled oscillator VCO, 1 signal or second voltage controlled oscillator VCO, 2 signals by driving circuit driven in rotation voltage transformer, and the information of carrying out sends.
3. a kind of coupling communicator that is used for aircraft tire pressure real-time monitoring system according to claim 2 is characterized in that: described first voltage controlled oscillator VCO 1 and second voltage controlled oscillator VCO, 2 output signal frequencies are respectively 25kHz and 100kHz.
4. a kind of coupling communicator that is used for aircraft tire pressure real-time monitoring system according to claim 1 is characterized in that: described monitoring modular modulating unit has and the identical structure and parameter of control module modulating unit.
5. a kind of coupling communicator that is used for aircraft tire pressure real-time monitoring system according to claim 1 is characterized in that: described control module demodulating unit comprises the first phase demodulator PD1, the second phase demodulator PD2, filter capacitor C
1And C
2, operational amplifier A MP, pull-up resistor R
L, voltage controlled oscillator VCO, timing resistor R
TWith timing capacitor C
TSignals of rotating transformer is applied to the input end of the first phase demodulator PD1 and the second phase demodulator PD2 respectively through the control module coupling capacitance, and the output of the first phase demodulator PD1 is through filter capacitor C
2Give voltage controlled oscillator VCO after the filtering, the second phase demodulator PD2 is given in the output of voltage controlled oscillator VCO then, and the output of the second phase demodulator PD2 is through filter capacitor C
1Filtering, operational amplifier A MP amplify and pull-up resistor R
LOn just can get digital signal after the demodulation after drawing; Timing resistor R
TWith timing capacitor C
TCooperate voltage controlled oscillator VCO to produce required frequency signal.
6. a kind of coupling communicator that is used for aircraft tire pressure real-time monitoring system according to claim 1 is characterized in that: described monitoring modular demodulating unit has and the identical structure and parameter of control module demodulating unit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010100135655A CN101774336B (en) | 2010-01-08 | 2010-01-08 | Coupling communicator used for real-time monitoring system of tire pressure of airplane |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010100135655A CN101774336B (en) | 2010-01-08 | 2010-01-08 | Coupling communicator used for real-time monitoring system of tire pressure of airplane |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101774336A CN101774336A (en) | 2010-07-14 |
| CN101774336B true CN101774336B (en) | 2011-11-16 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2010100135655A Expired - Fee Related CN101774336B (en) | 2010-01-08 | 2010-01-08 | Coupling communicator used for real-time monitoring system of tire pressure of airplane |
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|---|---|
| CN (1) | CN101774336B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110182384B (en) * | 2019-05-27 | 2022-12-02 | 西北工业大学 | Electrical system display simulator and method and aircraft power system comprehensive test system |
| CN114475101A (en) * | 2022-03-09 | 2022-05-13 | 中南大学 | Multi-parameter wireless monitoring system for aircraft tire |
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2010
- 2010-01-08 CN CN2010100135655A patent/CN101774336B/en not_active Expired - Fee Related
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| CN101774336A (en) | 2010-07-14 |
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