CN107390668B - Determine that antiskid brake control device adds the method for tight reliability test sectional plane - Google Patents
Determine that antiskid brake control device adds the method for tight reliability test sectional plane Download PDFInfo
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- CN107390668B CN107390668B CN201710490988.8A CN201710490988A CN107390668B CN 107390668 B CN107390668 B CN 107390668B CN 201710490988 A CN201710490988 A CN 201710490988A CN 107390668 B CN107390668 B CN 107390668B
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B23/00—Testing or monitoring of control systems or parts thereof
- G05B23/02—Electric testing or monitoring
- G05B23/0205—Electric testing or monitoring by means of a monitoring system capable of detecting and responding to faults
- G05B23/0259—Electric testing or monitoring by means of a monitoring system capable of detecting and responding to faults characterized by the response to fault detection
- G05B23/0283—Predictive maintenance, e.g. involving the monitoring of a system and, based on the monitoring results, taking decisions on the maintenance schedule of the monitored system; Estimating remaining useful life [RUL]
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Abstract
A kind of determining antiskid brake control device adds the method for tight reliability test sectional plane, determines proof stress with the data of same numbers circuit antiskid brake control device Highly Accelerated Life Test, is formed and add tight reliability test sectional plane.Proof stress in the present invention plus tight test profile not only includes the extremum conditions of environmental test, it also include the case where being greater than environment extremum conditions, according to the invention plus tight test profile carries out reliability test, determines and correct the potential faults of the antiskid brake control device.The present invention utilizes the antiskid brake control device with computer control, it has been formulated by the method for improving proof stress magnitude and has added tight test profile, to improve the ability for exciting the product failure hidden danger, the reliability test of exemplar in kind is gradually substituted, resource and energy consumption are reduced.
Description
Technical field
The present invention relates to civil aircraft electronic products to develop field, specifically determines antiskid brake control using computer technology
Device reliability processed adds the method for tight test profile, adds tight data source in the physical testing data of antiskid brake control device,
Here it is the origins of semi-physical simulation.
Background technique
The reliability test of existing civil aircraft electronic product is all not added sternly, and test applies true timing under power on condition
Temperature, humidity, vibration integrated stress.It is cutd open using the test that computer technology carries out the section and exemplar in kind of reliability test
Face is identical, is also not added tight.Described plus tight refer to passes through raising temperature, vibration and electric stress numerical value, to improve the effect of excitation failure
Fruit.
Foreign current situation:
Reliability test accepted standard has: IEC60300-3-5 " reliability test ", Unite States Standard MIL-STD-781
《Reliability Testing for Engineering Development,Qualification,and
Production ", the amplitude and application time of proof stress are calculated according to the data that test obtains；Testing program is using index point
Cloth is formulated.When carrying out reliability test using model of the computer technology to electronic product, test profile and exemplar in kind
It is identical.
Present status in China:
1) accepted standard has: referring to the GB/T5080.1 " reliability test " of IEC60300-3-5 authorizing standard, logical
Apply temperature, vibration, humidity synthetic chemistry laboratory under electric condition, what the amplitude and application time of proof stress were obtained according to test
Statistical data calculates.When carrying out reliability test using model of the computer technology to electronic product, test profile and material object
Exemplar it is identical.
2) the acceleration reliability test method of 201110443565.3 airplane antiskid braking control devices is invented by anti-skidding brake
The working stress of truck control device is included in test profile and GB/T5080.1, GJB899 reliability test standard do not apply work
Stress is compared, and has the effect of obviously exciting failure, verifying product quality.
The defect of the domestic and international prior art
1) according to analyzing both at home and abroad using data, determine that the reliability test sectional plane of electronic product excites using existing standard
The dynamics of failure is insufficient, there is the fact both at home and abroad: test all passes through, but failure is more in use, and reason test is answered
Power applies deficiency, excites the effect of failure bad.
2) invention 201110443565.3 solves the problems, such as to apply working stress in reliability test sectional plane, but not
Consider high magnitude environmental stress and power supply characteristic, it cannot be in the weak link of deeper time excitation electronic product.
Summary of the invention
It, cannot be in deeper time excitation electronic product to overcome the effect of excitation failure existing in the prior art bad
The deficiency of weak link, the invention proposes a kind of methods that determining antiskid brake control device adds tight reliability test sectional plane.
Detailed process of the invention is:
Step 1, the mathematical model of antiskid brake control device is established.The digital mould for establishing antiskid brake control device
Type includes model of failure distribution, high temperature model, low-temperature model and the model of vibration of the antiskid brake control device.
Step 2, the mission profile of the antiskid brake control device is determined:
The mission profile of the antiskid brake control device includes:
Vibration stress in I mission profile:
Vibration stress in the mission profile includes the maximum vibration stress numerical of landing braking moment, landing rear brake
The vibration stress numerical value in the vibration stress numerical value and ground taxi in vehicle and starting heats stage differential brake stage；The land brake
The maximum vibration stress numerical of moment is 20Grms, and landing rear braking and the vibration stress numerical value in starting heats stage are
15Grms, the vibration stress numerical value in ground taxi differential brake stage are 10Grms.
High-temperature temperature in II mission profile and add it is tight after high-temperature temperature:
High temperature stress in the mission profile includes high-temperature temperature and plus tight high-temperature temperature；Determining high temperature 70
℃；Adding tight high-temperature temperature is 115 DEG C；High-temperature duration with plus tight maximum temperature duration be 70min.
Cryogenic temperature in III mission profile and plus it is tight after cryogenic temperature
The gentle low temperature determined in the mission profile is -55 DEG C；Adding tight cryogenic temperature is -65 DEG C；When low temperature continuous
Between with plus tight cryogenic temperature duration be 70min.
Temperature shock stress in IV mission profile and add it is tight after temperature shock
The temperature shock stress determined in the mission profile is 30 DEG C/min~40 DEG C/min.
Humidity in V mission profile
The humidity modification determined in the mission profile occurs in ground hot stage, and the humidity modification is dew point
Temperature t, t >=31 DEG C.
VI determines supplied character
The supply voltage over-voltage of the stable state determined in the mission profile and under-voltage range are 20V~32V.
So far, it is determined that the antiskid brake control device mission profile.
Step 3, the room temperature numerical value added in tight test profile is determined
Determining room temperature numerical value is 25 DEG C.
Step 4, the vibrating numerical added in tight test profile is determined
In adding tight test profile, other than humidification periods section, remaining time is all vibrated.
The maximum vibration magnitude is 24Grms；It takes off, the vibration magnitude during landing braking is 15Grms, ground turn
Vibration magnitude during curved is 10Grms.
Step 5, it formulates and adds tight test profile
The first step, temperature and humidity add tight test profile
The temperature refer to high temperature and add it is tight after high temperature between variation.
Described plus tight temperature is 115 DEG C, continues 70min.- 65 DEG C are cooled to the rate of temperature fall of 40 DEG C/min.- 65
DEG C keep 70min.70 DEG C are warming up to the heating rate of 40 DEG C/min.In 70 DEG C of holding 70min.With the cooling speed of 40 DEG C/min
Rate is cooled to -55 DEG C.115 DEG C are warming up to the heating rate of 40 DEG C/min.In 115 DEG C of holding 70min.With the drop of 40 DEG C/min
Warm rate is cooled to -65 DEG C.In -65 DEG C of holding 70min.25 DEG C are warming up to the heating rate of 40 DEG C/min.It is kept at 25 DEG C
Time 120min.115 DEG C of n are warming up to the heating rate of 40 DEG C/min.
The humidity applies in the 295.2min~365.2min for adding tight test profile, dew-point temperature t >=31 DEG C.
Tight test profile is added to be input in the mathematical model of antiskid brake control device determining temperature and humidity.
Second step determines vibration plus tight test profile
Identified vibration plus tight test profile are that the start time point setting vibration stress of Cong Jiayan test profile is
24Grms, time of vibration are set as 70min.Will vibration magnitude fall to 10Grms, since 70min time point vibration to
147.9min.Magnitude up-regulation will be vibrated to 24Grms at 147.9min time point, since 147.9min time point vibration to
217.9min.217.9min time point by vibrate magnitude be lowered to 15Grms, since 217.9min time point vibration to
295.2min.Magnitude up-regulation will be vibrated to 24Grms at 295.2min time point, since 295.2min time point vibration to
365.2min.365.2min time point by vibrate magnitude be lowered to 15Grms, since 365.2min time point vibration to
442min.It is lowered to 10Grms by magnitude is vibrated at 442min time point, is vibrated since 442min time point to 565.5min.
Determining vibration plus tight test profile are input in the mathematical model of antiskid brake control device.
Third step determines that line under-voltage/over-voltage adds tight test profile.
Identified line under-voltage/over-voltage adds tight test profile to be that supply voltage is arranged from the start time point of test profile
For 32V, when application a length of 70min.20V is set by voltage at 70min time point, applies duration and proceeds to 147.9min.?
Voltage is set 32V by 147.9min time point, applies duration and proceeds to 217.9min.Voltage is set at 217.9min time point
It is set to 20V, applies duration and proceeds to 295.2min.32V is set by voltage at 295.2min time point, applies duration and proceeds to
365.2min.20V is set by voltage at 365.2min time point, applies duration and proceeds to 442min.At 442min time point
32V is set by voltage, applies duration and proceeds to 565.5min.By the under-voltage/mistake plus tight pressure under the conditions of determining voltage stabilization
Test profile is input in the mathematical model of antiskid brake control device.
So far, the work that determining antiskid brake control device adds tight reliability test sectional plane is completed.
In the prior art, since low amounts value proof stress is difficult to inspire the weak link of electronic product profound level, so
The present invention utilizes the antiskid brake control device with computer control, has been formulated and has been added by the method for improving proof stress magnitude
Tight test profile gradually substitutes the reliability test of exemplar in kind, reduces money to improve the ability for exciting the product failure hidden danger
Source and energy consumption.
In the present invention, add the proof stress in tight test profile not only and include the extremum conditions of environmental test, also comprising big
In the environment extremum conditions the case where, this point is different from existing standard, provides in GJB899 4.3.1: " the ring of reliability test
Border condition is different from the extremum conditions of environmental test, and what it answered that the simulation Device under test of timing undergoes in use most important answers
Power, the order of priority of identified sign are as follows: a) measured stress ...." due to the statistics in existing domestic and international reliability test standard
Stress is not counted in the stress more than extreme value environmental condition, but these conditions do not count on only, when occurring in use,
Product will break down.Being included in higher than the proof stress of extreme value is for more significant excitation failure.In the present invention:
1) according to HB5830.8 high temperature, high temperature extreme value is 70 DEG C；Apply operating current test according to 201310169039.1
The method of the antiskid brake control device high temperature limit, the high temperature limit of the antiskid brake control device is 115 DEG C~
125 DEG C, high temperature magnitude range of the invention are as follows: more than or equal to 70 DEG C~less than or equal to 125 DEG C.
3) according to HB5830.9 low temperature, cryogenic extremes are -55 DEG C, according to a kind of 201310169901.9 antiskid brake controls
The method of device low temperature step test, the low temperature damage limit of the antiskid brake control device are -70 DEG C~-80 DEG C, the present invention
Low temperature magnitude range are as follows: be less than or equal to -55 DEG C~be more than or equal to -80 DEG C.
4) room temperature temperature setting is 25 DEG C, for being exposed to the potential faults ejected under high temperature, cryogenic conditions.
5) according to a kind of 201310169895.7 methods of antiskid brake control device flutter failure limit test of invention, vibration
Momentum value value range: greater than measured value is less than the limit of rupture.
6) according to invention 201310193684.7 using fast temperature variation test antiskid brake control device potential faults
Method, rate temperature change value are as follows: 40 DEG C/min.
7) operating voltage applies over-voltage and the under-voltage numerical value under stable condition referring to GJB181A.
8) testing time: computer iterations calculation times 30000 times, runing time about 1 day.
According to the invention plus tight test profile carries out reliability test, determines and correct the antiskid brake control device
Potential faults.
Proof stress of the invention uses the data of same numbers circuit antiskid brake control device Highly Accelerated Life Test
It determines, is formed and add tight reliability test sectional plane.Test data of the test profile of the present invention referring to following invention:
1) a kind of 201310169901.9 method of antiskid brake control device low temperature step test；
2) 201310169039.1 apply the method that operating current tests the antiskid brake control device high temperature limit；
3) a kind of 201310169895.7 method of antiskid brake control device flutter failure limit test；
4) 201310193684.7 method that antiskid brake control device potential faults are tested using fast temperature variation；
5) 201410312137.0 method for testing antiskid brake control device failure under complex working conditions.
The present invention is with the difference for quoting above-mentioned 5 inventions:
1) difference that exemplar test in kind and computer technology calculate: above-mentioned 5 inventions are controlled using antiskid brake
The test that device products in kind carries out, and the present invention is computation model and the test to computer input antiskid brake control device
Condition calculates the potential faults of antiskid brake control device.
2) profession difference: above-mentioned 5 inventions are respectively used to excitation antiskid brake control device, i.e. antiskid brake control device
Low temperature, high temperature, vibration, the potential faults under the conditions of temperature change and combined stress, be five tests independently carried out, pass through
For the improvement that high temperature, low temperature, vibration, temperature change, combined stress weak link carry out, antiskid brake control device is improved
Development quality.Prior art environmental test standard have the U.S. D0-160 " environmental condition and test procedure of airborne equipment ",
GMW8287 " high accelerated aging, highly accelerated stress screen and sampling observation ", HB5830 " environmental condition of airborne equipment and test side
Method ", can test product work normally at ambient conditions.And the present invention be under the conditions of adding tight reliability test sectional plane,
The weak links of reliability for determining antiskid brake control device, according to GB/5080.1 " reliability test ", GJB899 " reliability
Identification and acceptance test " it provides, reliability test carries out under temperature, humidity, three integrated environments of vibration and power on condition, tries
Test the time, synthetic chemistry laboratory magnitude has strict demand, need to according to the reliability index of product determine, it is special to belong to reliability test
Industry.The present invention, by improving environmental stress magnitude and increasing power supply characteristic, improves on the basis of existing reliability test standard
Excite the effect of potential faults.
3) difference of testing equipment: above-mentioned 5 inventions need to set using reliability enhancement testing equipment, three compbined tests
Equipment that is standby, applying liquid nitrogen cooling.And the antiskid brake control device that the present invention then passes through computer simulation can be realized.
The testing equipment and software that the present invention uses are shown in Table 1.
1 testing equipment of table and software register
| Sequence | Title | Manufacturer | The trade mark or version | Purposes |
| 1 | Computer workstation | Hewlett-Packard Corporation, the U.S. | HPZ800 | It calculates |
| 2 | CITIA | America DS Inc | V5R18 | Drawing 3 D graphics |
| 3 | FLOTHERM | MENTORGRAPHICS company, the U.S. | 8.1 | Heat calculates |
| 4 | NASTRAN | MSC company, the U.S. | 2008r1 | Model analysis |
| 5 | CAVLE PWA | Univ Maryland-Coll Park USA | 5.3.1 | Accident analysis |
Due to adding sternly to test profile, implementation result is produced.Proof stress of the present invention applies duration in test profile
Ratio compared with code test section and be shown in Table 2.
2 antiskid brake control device Standard Task section of table plus tight test profile compare
1, excite the effect of antiskid brake control device failure: test profile determined using the method for the present invention plus tight is carried out
The reliability tests of three antiskid brake control device models, adds the temperature stress magnitude of tight test profile to have: -65 DEG C, -55
DEG C, 25 DEG C, 79 DEG C, 115 DEG C, add the vibration stress magnitude of tight test profile to have: 10Grms, 15Grms, 24Grms, humidity are normal
Rule value: electric leakage temperature t >=31 DEG C.Test result are as follows:
1) No. 001 model is established according to airfreighter antiskid brake control device, is established according to the method for the present invention
Section carries out reliability test in a computer, inspires programmable logic circuit through test and high temperature failure occurs, improved to disappear
In addition to the failure.
2) No. 002 model is established according to passenger airplane antiskid brake control device, is established according to the method for the present invention
Section carries out reliability test in a computer, inspires solid-state relay through test and vibration fault occurs, improved to eliminate
The failure.
3) No. 003 model is established according to feeder liner antiskid brake control device, is established according to the method for the present invention
Section carries out reliability test in a computer, inspires triode through test and low temperature failure occurs, improved to eliminate the event
Barrier.
2, energy consumption and the wasting of resources that exemplar reliability test in kind generates the social benefit generated: do not occur.
3, the reduction of expenditure effect generated, the antiskid brake box reliability index is 3000h in embodiment, presses most short test
Time calculated savings funds effect:
1) exemplar testing expenses in kind: ten thousand yuan of 3000h × 1.1 × 500 yuan/h+2000000=365；1.1 be high wind in short-term
The safety coefficient of dangerous testing program, testing expenses calculate by the hour, and 500 yuan per hour；Every 1,000,000 yuan of tests exemplar expense.
Testing expenses: 3,650,000 yuan.
2) computer calculates expense: for 24 hours × 150 yuan=3600 yuan.
Saving reliability test expense: 3,650,000 yuan -0.36 ten thousand yuan=364.64 ten thousand yuan.
4, time-saving effect: it can complete to determine the work of weak link using the 1 day time of computer technology, prevent
The average time between failures MTBF requirement of sliding braking control device are as follows: 3000h, high risk scheme is tested in short-term according to GJB899
No. 21 scheme of scheme, 1.1 times of test period MTBF, it may be assumed that 1.1 × 3000h=3300h=137.5 days.One product can
Save 136 day time.
5, environmentally friendly prospect: carrying out reliability using computer technology and add tight test, since it does not damage electronic product, does not produce
Raw testing expenses and quick the characteristics of obtaining electronic product potential faults, have significant protection environmental benefit, energy-saving effect
Benefit has significant development prospect.
Detailed description of the invention
Fig. 1 is of the invention plus tight test profile, and t >=31 DEG C are dew-point temperatures in figure.
Fig. 2 is flow chart of the invention.
Specific embodiment
The present embodiment is to determine to add tight reliability test sectional plane, the section to a kind of civil aircraft antiskid brake control device
For carrying out reliability test in a computer.High temperature, low temperature, temperature shock, vibration, power supply spy are incorporated in test profile
Property content of the test, 4 inventions that the numerical value of environmental test stress is quoted referring to the present invention determine that the voltage in supplied character is joined
It is determined according to GJB181A.
Number of the proof stress of the present embodiment referring to same numbers circuit antiskid brake control device Highly Accelerated Life Test
According to determination, is formed and add tight reliability test sectional plane.Test data of the present embodiment referring to following invention:
1) a kind of 201310169901.9 method of antiskid brake control device low temperature step test
2) 201310169039.1 apply the method that operating current tests the antiskid brake control device high temperature limit
3) a kind of 201310169895.7 method of antiskid brake control device flutter failure limit test
4) 201310193684.7 method that antiskid brake control device potential faults are tested using fast temperature variation
The testing equipment and software that the present embodiment is used are shown in Table 1.
1 testing equipment of table and software register
| Sequence | Title | Manufacturer | The trade mark or version | Purposes |
| 1 | Computer workstation | Hewlett-Packard Corporation, the U.S. | HPZ800 | It calculates |
| 2 | CITIA | America DS Inc | V5R18 | Drawing 3 D graphics |
| 3 | FLOTHERM | MENTORGRAPHICS company, the U.S. | 8.1 | Heat calculates |
| 4 | NASTRAN | MSC company, the U.S. | 2008r1 | Model analysis |
| 5 | CAVLE PWA | Univ Maryland-Coll Park USA | 5.3.1 | Accident analysis |
Step 1, the mathematical model of antiskid brake control device is established.
The first step establishes the model of failure distribution of the antiskid brake control device
In the innovation and creation application No. is 201610373928.3, application No. is the invention of 201610373996.X wounds
In making, and application No. is demonstrated respectively in 201610373390.6 innovation and creation antiskid brake control device high temperature,
Low temperature, vibration fault obey Weibull distribution, and the present invention quotes the model of failure distribution, model of failure distribution are as follows:
In formula (1): t is the time；FnIt (t) is the cumulative failure distribution function of antiskid brake control device；M is Weibull point
The form parameter of cloth, the size of m indicate that failure divides spread of distribution；t0For scale parameter, reduces and amplification distribution function is sat
The effect of scale.When iteration improves the antiskid brake control device in calculating process, distribution parameter will change.
The model of failure distribution inputs computer, and Calculation of Reliability is carried out during adding tight reliability test.
Second step establishes the high temperature model of the antiskid brake control device
Using the modeling method of 2016108765157 " methods for determining antiskid brake control device high temperature weak link ".
Used test instrument is shown in Table 2.
2 Thermal test instrument summary sheet of table
| Sequence | Title | Model | Manufacturer | Purposes |
| 1 | Thermal imaging system | TI55 | FLUX company, the U.S. | Acquire thermal signal |
| 2 | Data collecting instrument | ANGILENT34970A | ANGILENT company, the U.S. | Acquire dsc data |
| 3 | Thermocouple | T-type | ANGILENT company, the U.S. | Acquire the temperature of high-temperature device |
The modeling procedure that antiskid brake control device high temperature calculates are as follows:
I, prepare the structural information of the antiskid brake control device
The structural information includes the composition and connection type of the antiskid brake control device.
The antiskid brake control device is made of shell and 2 pieces of circuit boards, and 2 fast-circuit plates are respectively as follows: control panel, record
Plate；It is connected using slot mode with shell.
The information of shell collected includes the shape and size, material, seal form of the shell.
II, prepare the information of all kinds of components
2 pieces of circuit boards include 12 integration modules altogether, model, weight, the size, encapsulation of component on integration module
Form information, as the information for calculating high temperature weak link.
III, draw the three-dimensional geometric shapes of the antiskid brake control device
Using the three-dimensional geometric shapes of the CITIA Software on Drawing antiskid brake control device, it is divided into following 3 partial content:
1) three-dimensional geometric shapes of the antiskid brake control device finished product state；
2) three-dimensional geometric shapes of the antiskid brake control device circuit board；
3) three-dimensional geometric shapes of the integration module of the antiskid brake control device, component.
So far, the preparation of antiskid brake control device high temperature calculating is completed.
IV, following revision is carried out according to the three-dimensional geometric shapes of the antiskid brake control device:
1) remove the hole that diameter is less than 0.65mm；
2) remove the boss that size is less than 0.65mm；
3) connectors such as screw, connector, the cable unrelated with heat analysis are deleted.
V, according to the location information of all components and packing forms, temperature range, the electricity of each type component
Current voltage, plugging mode, weight and outer dimension carry out circuit board modeling.The above- mentioned information of the various types of component are equal
It is obtained by purchasing handbook.
VI, input relevant parameter
Input the power consumption of component of the power consumption more than or equal to 0.05W, case material, antiskid brake control device building ring
Border condition.In the present embodiment, it is:
1) case material: aluminum alloy materials；
2) component power consumption: the component to all power consumptions more than or equal to 0.05W carries out power consumption setting, and power consumption is less than
The component and whole plate power consumption of 0.05W is additional on circuit boards；
3) environmental condition: GJB150 is up to 70 DEG C；Present invention determine that when calculating error less than ± 5%, before 70 DEG C
Terminate to calculate；When error is greater than ± 5%, environmental condition is higher than 70 DEG C, be less than up to reaching calculating error and measurement error ±
5%.
By the gravity direction of antiskid brake control device according to level installation direction setting.
VII, grid dividing: region of the power consumption greater than 0.05W is set as domain grid and is controlled.Position other than the region
It is automatically generated by software.
Third step establishes the low-temperature model of the antiskid brake control device
Using the modeling method of 2016108767805 " methods for determining antiskid brake control device low temperature weak link ".
Used test instrument is shown in table 2 of the present invention.
I, II, III, IV, the V of the same high temperature of the present invention modeling of I, II, III, IV, the V of low temperature modeling.
VI, input relevant parameter
Input the power consumption of component of the power consumption less than 0.05W, case material, antiskid brake control device working environment item
Part.In the present embodiment, it is:
1) case material: aluminum alloy materials；
2) component power consumption: the component to all power consumptions less than 0.05W carries out power consumption setting.Power consumption is greater than 0.05W's
Component and whole plate power consumption are attached on the circuit board where the component；
3) environmental condition: minimum -55 ± 2 DEG C of GJB150 regulation, the present embodiment determines, is less than ± 5% when calculating error
When, terminate to calculate before -55 DEG C；When error is greater than ± 5%, environmental condition is lower than -55 DEG C, calculates error and reality until reaching
It surveys error and is less than ± 5%.By the gravity direction of antiskid brake control device according to level installation direction setting.
4) grid dividing: the region by power consumption less than 0.05W is set as domain grid and controls；Position other than the region
It is automatically generated by software.
4th step establishes the model of vibration of the antiskid brake control device
Using the modeling method of 2016108765104 " methods for determining antiskid brake control device vibration weak link ".
The software of use: drawing three-dimensional geometric figure software: CITIA V5R18；Finite element modeling software: Hypermesh/
10.0；Finite element analysis software: NASTRAN2008r1.
The environmental condition of input: room temperature；Model analysis order: three ranks；Analyze frequency range: 20Hz~2000Hz；Frequency response
Analyze step-length: 20Hz.
I, the condition that antiskid brake control device vibration weak link calculates is determined
1) the vibration magnitude applied in calculating is determined, according to actual measurement, the maximum vibration magnitude of the antiskid brake control device
For 20Grms, minimum 10Grms.Determine the vibration magnitude inputted in calculating process are as follows: 10Grms~20Grms.
2) Position of Vibrating in calculating is determined, the control panel and data board of antiskid brake control device are all by being distributed in four
Screw on a angle is connected with shell.Determine that Position of Vibrating is the screw installation position of control panel, data board.
3) it determines the direction of excitation in calculating, under vibrating conditions, is displaced maximum perpendicular to the direction of circuit board, determines and swash
Direction shake for the direction perpendicular to control panel and data board.
4) determine that the vibration spectral pattern in calculating is HB5830.5E grades of broad-band random vibration spectrums.
5) determine that the constrained and constraint direction of circuit board, the constrained of circuit board are screw position；Constraint direction
For the constraint condition of three translational degree of freedom, three rotational freedoms.
II, the model of vibration of the antiskid brake control device is determined
1) it according to the dimension of picture in the drawing of the antiskid brake control device, component inventory, component handbook, uses
CITIA V5R18 establishes the three-dimensional geometric shapes of the antiskid brake control device.
2) according to the three-dimensional geometric shapes of following rules modification antiskid brake control device: removing the hole that diameter is less than 1mm；
Remove the boss that thickness is less than 0.5mm；Remove the fillet that radius is less than 1mm；The weight for being less than or equal to 2g component is added in electricity
On the plate of road, component of the quality greater than 2g carries out modeling and weight setting, keeps the weight of the antiskid brake control device constant；First device
The quality such as part use, isometric mass block substitution.
III, the parameter of the antiskid brake control device is set
Setting antiskid brake control device shell is aluminum material.The material that antiskid brake control device circuit board is arranged is
FR4 epoxy glass fiber plate.The encapsulation of component summarizes are as follows: Plastic Package, Metal Packaging, ceramic package.
IV, FEM meshing
First using the grid dividing for scanning completion antiskid brake control device；Secondly shell is individually divided；So
Cell size control is carried out to two pieces of circuit boards afterwards；Then region division is carried out to each module；Finally component is carried out independent
It divides.Finally obtained number of grid is 119437, and mesh quality is examined to be clicked using algorithm included in Hypermesh and be completed.
Step 2, the mission profile of the antiskid brake control device is determined
Add tight test profile using stress according in mission profile, excites potential faults.In the test of exemplar in kind
Cheng Zhong adds tight test profile that can damage exemplar, and the consume expense of tests exemplar occurs.Antiskid brake is controlled in a computer and is filled
The model set carries out plus tight reliability test is not related to tests exemplar consume.
GJB451A 2.1.6.5 defines mission profile are as follows: " product was completed in assignment of mission this period, experienced
The description of event and environment." defined according to GJB451A, the mission profile of the antiskid brake control device is aircraft from shutdown
Level ground to take-off line, from take-off line braking reinforcing to starting heats, climb, navigate by water, decline, landing braking, the full mistake for going back to airplane parking area
Journey；Whole process 2h.
According to GJB899 4.3.2 provide, combined environment test condition include: electric stress, vibration stress, temperature stress,
Humidity modification.
The mission profile of the antiskid brake control device includes:
Vibration stress in I mission profile
It is 20Grms, landing rear braking and starting heats rank according to the maximum vibration stress numerical of actual measurement landing braking moment
The vibration stress numerical value of section is 15Grms, and the vibration stress numerical value in ground taxi differential brake stage is 10Grms.Referring to invention
The flutter failure limit of the 201310169895.7 antiskid brake control devices is greater than 24Grms, in order to add tight experimental condition to excite
Potential faults, the maximum vibration magnitude of the present embodiment are 24Grms.
High-temperature temperature in II mission profile and add it is tight after high-temperature temperature；
In-flight actual measurement ground high temperature is 40 DEG C~70 DEG C.Referring to the test data of invention 201310169039.1, this hair
Bright to use 70 DEG C of extreme value high temperature, adding tight maximum temperature is 115 DEG C.
The high temperature limit of the antiskid brake control device is 125 DEG C, determines that maximum temperature is 115 DEG C, more broken than high temperature
The bad limit is 10 DEG C low.HB5830.8 " airborne equipment environmental condition and test method high temperature " provides that high temperature extreme value is 70 DEG C, by 70
One of high temperature scale DEG C as test profile of the present invention；High-temperature duration with plus tight maximum temperature duration be
70min。
Cryogenic temperature in III mission profile add it is tight after cryogenic temperature
In-flight actual measurement ground low temperature is -30 DEG C~-55 DEG C.Referring to the test data of invention 201310169901.9, originally
Invention uses -55 DEG C of extreme value low temperature, and adding tight minimum temperature is -65 DEG C.
The low temperature damage limit of the antiskid brake control device are as follows: -80 DEG C, determine that minimum temperature is -65 DEG C, it is more broken than low temperature
The bad limit is 15 DEG C high.HB5830.9 " airborne equipment environmental condition and test method low temperature " provides that cryogenic extremes are -55 DEG C, will -
55 DEG C of one of lower temperature scales as test profile of the present invention；The low temperature continuous time with plus tight minimum temperature duration be
70min。
Temperature shock stress in IV mission profile and add it is tight after temperature shock；
Process of taking off and climb experience temperature changes from high to low, and landing mission experience temperature changes from low to high.
5 DEG C/min~15 DEG C of observed temperature rate of change/min.The antiskid brake control device is given referring to invention 201310193684.7
The maximum temperature rate of change of application is 30 DEG C/min, in order to excite the potential faults of the antiskid brake control device, this implementation
Example adds tight rate temperature change to be 40 DEG C/min.
Humidity in V mission profile；
Humidity occurs in ground hot stage, and the humidity is dew-point temperature t, t >=31 DEG C.
VI determines supplied character
With reference to GJB181A " aircraft electrical supply parameters ", the ability to bear of electronic product when supplied character is mains fluctuations,
Also it is power supply characteristic.The nominal voltage for being supplied to the antiskid brake control device is 28V, according to GJB181A, the electricity of stable state
Source electric voltage over press and under-voltage range are: 20V~32V.
So far, it is determined that the duration and various parameters of the antiskid brake control device mission profile.
Step 3, the room temperature numerical value added in tight test profile is determined
The purpose of selection room temperature test is to determine the failure ejected in high temperature, low temperature, temperature change test process
Hidden danger, these potential faults often reveal under normal temperature conditions.Room temperature temperature is 25 DEG C.
Step 4, the vibrating numerical added in tight test profile is determined
In adding tight test profile, other than humidification periods section, remaining time is all vibrated.
The vibration magnitude of 20Grms is only in moment of landing according to statistics, and proportion is insufficient in a mission profile
1%, in order to excite the vibration fault of antiskid brake control device, maximum vibration magnitude is increased to 24Grms by the present invention, and
The time of vibration of 24Grms extends.Surveying 15Grms is the vibration magnitude to take off, during landing braking, and actual measurement 10Grms is ground
Vibration magnitude during the turning of face.
Step 5, it formulates and adds tight test profile
The first step, temperature and humidity add tight test profile
The temperature refer to high temperature and add it is tight after high temperature between variation.
Described plus tight temperature is 115 DEG C, continues 70min.- 65 DEG C are cooled to the rate of temperature fall of 40 DEG C/min.- 65
DEG C keep 70min.70 DEG C are warming up to the heating rate of 40 DEG C/min.In 70 DEG C of holding 70min.With the cooling speed of 40 DEG C/min
Rate is cooled to -55 DEG C.115 DEG C are warming up to the heating rate of 40 DEG C/min.In 115 DEG C of holding 70min.With the drop of 40 DEG C/min
Warm rate is cooled to -65 DEG C.In -65 DEG C of holding 70min.25 DEG C are warming up to the heating rate of 40 DEG C/min.It is kept at 25 DEG C
Time 120min.115 DEG C of n are warming up to the heating rate of 40 DEG C/min.
Humidity applies in the 295.2min~365.2min for adding tight test profile, dew-point temperature t >=31 DEG C.
So far, it is determined that temperature and humidity adds tight test profile.
Tight test profile is added to be input in the mathematical model of antiskid brake control device determining temperature and humidity.
Second step determines vibration plus tight test profile
It is greater than 24Grms referring to the flutter failure limit of the 201310169895.7 antiskid brake control devices of invention, in order to
Excited vibrational failure, the maximum vibration magnitude of the present embodiment are 24Grms.
It is 24Grms from adding the start time point of tight test profile that vibration stress is arranged, time of vibration is set as 70min.So
Vibration magnitude is fallen into 10Grms afterwards, is vibrated since 70min time point to 147.9min.
Magnitude up-regulation will be vibrated to 24Grms at 147.9min time point, since 147.9min time point vibration to
217.9min.217.9min time point by vibrate magnitude be lowered to 15Grms, since 217.9min time point vibration to
295.2min.Magnitude up-regulation will be vibrated to 24Grms at 295.2min time point, since 295.2min time point vibration to
365.2min.365.2min time point by vibrate magnitude be lowered to 15Grms, since 365.2min time point vibration to
442min.It is lowered to 10Grms by magnitude is vibrated at 442min time point, is vibrated since 442min time point to 565.5min.
So far, it is determined that vibration plus tight test profile.
Tight test profile is added to be input in antiskid brake control device computation model determining vibration.
Third step determines that line under-voltage/over-voltage adds tight test profile
Under-voltage/over-voltage magnitude referring to GJB181A, when normal voltage is 28V, under the conditions of voltage stabilization are as follows: under-voltage
Voltage is 20V, and over-voltage voltage is 32V.The present invention in order to excite potential faults relevant with voltage, apply under the high temperature conditions by determination
Add overvoltage, applies under-voltage under cryogenic, do not apply normal voltage.Specific requirement are as follows:
Be 32V from the start time point of test profile setting supply voltage, when application a length of 70min.At 70min time point
20V is set by voltage, applies duration and proceeds to 147.9min.32V is set by voltage at 147.9min time point, when application
Length proceeds to 217.9min.20V is set by voltage at 217.9min time point, applies duration and proceeds to 295.2min.?
Voltage is set 32V by 295.2min time point, applies duration and proceeds to 365.2min.Voltage is set at 365.2min time point
It is set to 20V, applies duration and proceeds to 442min.32V is set by voltage at 442min time point, applies duration and proceeds to
565.5min。
So far, it is determined that under-voltage/over-voltage under the conditions of voltage stabilization adds tight test profile.By determining voltage stabilization item
Under-voltage/over-voltage under part adds tight test profile to be input in the mathematical model of antiskid brake control device.
So far, the work that determining antiskid brake control device adds tight reliability test sectional plane is completed.
Claims (5)
1. a kind of determining antiskid brake control device adds the method for tight reliability test sectional plane, which is characterized in that detailed process is:
Step 1, the mathematical model of antiskid brake control device is established；The mathematical model for establishing antiskid brake control device includes should
The model of failure distribution of antiskid brake control device, high temperature model, low-temperature model and model of vibration；
Step 2, the mission profile of the antiskid brake control device is determined:
The mission profile of the antiskid brake control device includes:
Vibration stress in I mission profile；
High-temperature temperature in II mission profile and add it is tight after high-temperature temperature；
Cryogenic temperature in III mission profile and plus it is tight after cryogenic temperature；
Temperature shock stress in IV mission profile and add it is tight after temperature shock；
Humidity in V mission profile；
VI determines supplied character；
So far, it is determined that the antiskid brake control device mission profile；
Step 3, the room temperature numerical value added in tight test profile is determined:
Determining room temperature numerical value is 25 DEG C；
Step 4, the vibrating numerical added in tight test profile is determined:
In adding tight test profile, other than humidification periods section, remaining time is all vibrated；
Maximum vibration magnitude is 24Grms；Take off, vibration magnitude during landing braking is 15Grms, during the turning of ground
Vibration magnitude be 10Grms；
Step 5, it formulates and adds tight test profile:
The first step, temperature and humidity add tight test profile；Tight test profile is added to be input to determining temperature and humidity
In the mathematical model of antiskid brake control device；
Second step determines vibration plus tight test profile；Tight test profile is added to be input to antiskid brake control dress determining vibration
In the mathematical model set；Third step determines that line under-voltage/over-voltage adds tight test profile；
By the under-voltage/mistake plus the tight number for pressing test profile to be input to antiskid brake control device under the conditions of determining voltage stabilization
In model；
So far, the work that determining antiskid brake control device adds tight reliability test sectional plane is completed.
2. determining that antiskid brake control device adds the method for tight reliability test sectional plane as described in claim 1, which is characterized in that
Vibration stress in the mission profile includes the maximum vibration stress numerical of landing braking moment, landing rear braking and takes off
The vibration stress numerical value and the vibration stress numerical value in ground taxi differential brake stage in sliding race stage；The landing braking moment
Maximum vibration stress numerical is 20Grms, and landing rear braking and the vibration stress numerical value in starting heats stage are 15Grms, ground
The vibration stress numerical value for sliding the differential brake stage is 10Grms；
High temperature stress in the mission profile includes high-temperature temperature and plus tight high-temperature temperature；70 DEG C of determining high temperature；Add
Tight high-temperature temperature is 115 DEG C；High-temperature duration with plus tight maximum temperature duration be 70min；
The low temperature determined in the mission profile is -55 DEG C；Adding tight cryogenic temperature is -65 DEG C；The low temperature continuous time with plus
The tight cryogenic temperature duration is 70min；
The temperature shock stress determined in the mission profile is 30 DEG C/min~40 DEG C/min；
The humidity modification determined in the mission profile occurs in ground hot stage, and the humidity modification is dew-point temperature
T, t >=31 DEG C；
The supply voltage over-voltage of the stable state determined in the mission profile and under-voltage range are 20V~32V.
3. determining that antiskid brake control device adds the method for tight reliability test sectional plane as described in claim 1, which is characterized in that
Identified temperature and humidity plus in tight test profile, the temperature refer to high temperature and add it is tight after high temperature between change
Change；
Described plus tight temperature is 115 DEG C, continues 70min；- 65 DEG C are cooled to the rate of temperature fall of 40 DEG C/min；It is protected at -65 DEG C
Hold 70min；70 DEG C are warming up to the heating rate of 40 DEG C/min；In 70 DEG C of holding 70min；It is dropped with the rate of temperature fall of 40 DEG C/min
Temperature is to -55 DEG C；115 DEG C are warming up to the heating rate of 40 DEG C/min；In 115 DEG C of holding 70min；With the cooling speed of 40 DEG C/min
Rate is cooled to -65 DEG C；In -65 DEG C of holding 70min；25 DEG C are warming up to the heating rate of 40 DEG C/min；In 25 DEG C of retention times
120min；115 DEG C of n are warming up to the heating rate of 40 DEG C/min；
The humidity applies in the 295.2min~365.2min for adding tight test profile, dew-point temperature t >=31 DEG C.
4. determining that antiskid brake control device adds the method for tight reliability test sectional plane as described in claim 1, which is characterized in that
Identified vibration plus tight test profile are that the start time point setting vibration stress of Cong Jiayan test profile is 24Grms, vibration
The dynamic time is set as 70min；Vibration magnitude is fallen into 10Grms, is vibrated since 70min time point to 147.9min；?
147.9min time point will vibrate magnitude up-regulation to 24Grms, vibrate since 147.9min time point to 217.9min；?
217.9min time point is lowered to 15Grms for magnitude is vibrated, and vibrates since 217.9min time point to 295.2min；?
295.2min time point will vibrate magnitude up-regulation to 24Grms, vibrate since 295.2min time point to 365.2min；?
365.2min time point is lowered to 15Grms for magnitude is vibrated, and vibrates since 365.2min time point to 442min；?
442min time point is lowered to 10Grms for magnitude is vibrated, and vibrates since 442min time point to 565.5min.
5. determining that antiskid brake control device adds the method for tight reliability test sectional plane as described in claim 1, which is characterized in that
It is 32V that identified line under-voltage/over-voltage, which adds tight test profile to be from the start time point of test profile setting supply voltage, is applied
Added-time a length of 70min；20V is set by voltage at 70min time point, applies duration and proceeds to 147.9min；In 147.9min
Voltage is set 32V by time point, applies duration and proceeds to 217.9min；20V is set by voltage at 217.9min time point,
Apply duration and proceeds to 295.2min；32V is set by voltage at 295.2min time point, applies duration and proceeds to
365.2min；20V is set by voltage at 365.2min time point, applies duration and proceeds to 442min；At 442min time point
32V is set by voltage, applies duration and proceeds to 565.5min.
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