CN109443518A - A kind of portable vehicle drag friction noise level monitor and method based on bluetooth - Google Patents
A kind of portable vehicle drag friction noise level monitor and method based on bluetooth Download PDFInfo
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- CN109443518A CN109443518A CN201811228214.9A CN201811228214A CN109443518A CN 109443518 A CN109443518 A CN 109443518A CN 201811228214 A CN201811228214 A CN 201811228214A CN 109443518 A CN109443518 A CN 109443518A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
- G01H11/00—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by detecting changes in electric or magnetic properties
- G01H11/06—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by detecting changes in electric or magnetic properties by electric means
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Abstract
The invention discloses a kind of portable vehicle drag friction noise level monitor and method based on bluetooth, collector fuselage is connect with magnetic support, first sensor is connect by the first A/D conversion module with first microprocessor, first microprocessor and collector bluetooth connection, power supply are connect with first sensor, first microprocessor；LCD screen and key are arranged in display fuselage surface, display fuselage interior includes second sensor, RAM card, display power supply, the 2nd A/D conversion module, the second microprocessor and display bluetooth, display power supply is connect with second sensor, the second microprocessor, second sensor is connect with the 2nd A/D conversion module, and the 2nd A/D conversion module, display bluetooth, RAM card, LCD screen are connect with the second microprocessor.The wireless connection of external noise collection device and display terminal can be achieved in the present invention；Monitoring, storage, differentiation and the early warning of the drag friction noise of achievable various vehicles.
Description
Technical field
The present invention relates to a kind of noise level monitors, and in particular to a kind of portable vehicle drag friction noise based on bluetooth
Detector and method.
Background technique
Drag friction noise is widely present in car, car, lorry, is the important performance assessment criteria of vehicle braking NVH performance
One of.Partial automobile issues grating noise in braking, has seriously affected the comfort of driver and passenger, this phenomenon has occurred
The reason of to be that automotive brake pads or brake disc performance occur abnormal, the raw manufacturer of automobile should be responsible for thus and ask for consumer's solution
Topic.But since brake oil has instantaneity, not reproducible, car owner is difficult to be collected into brake oil, due to absence of proof hardly possible
With to businessman's right-safeguarding.In addition, more for the research work of drag friction noise at this stage, mainly by vehicle road test and
Bench test carrys out simulating brake noise.In comparison, drag friction noise has higher reference during vehicle road test
Value, referentiability is higher, can more support correlative study.But at present in vehicle road test, drag friction Noise Acquisition instrument
Device is erroneous for installation, builds Noise Acquisition device and needs to expend more time, a whole set of noise collection device is sufficiently expensive.Therefore, anxious
A kind of portable brake frictional noise collection device need to be designed.
Noise-monitoring equipment there are many at present, can carry out the acquisition of conventional environment noise, be only able to display noise sound,
But it is unable to complete the storage of noise data, can not also carry out the other prediction of noise pollution level, such device is not able to satisfy braking
The test request of frictional noise.Meanwhile during drag friction noise monitoring, ratio is required to the installation site of Noise Acquisition device
Relatively stringent, most instruments are difficult to reach this requirement；The instrument of drag friction noise testing may be implemented in part, and volume is larger, pacifies
Dress process is cumbersome and price is higher.
Summary of the invention
The portable vehicle drag friction based on bluetooth that in view of the above existing problems in the prior art, the present invention provides a kind of
Noise level monitor and method.
To achieve the goals above, the technical solution adopted by the present invention is that: it is a kind of based on bluetooth portable vehicle braking
Frictional noise detector, including Noise Acquisition device and display terminal, Noise Acquisition device and display terminal pass through bluetooth connection；
Noise Acquisition device includes collector fuselage and magnetic support, and collector fuselage is connect with magnetic support, and collector fuselage interior includes the
One sensor, collector power supply, first microprocessor, the first A/D conversion module and collector bluetooth, first sensor pass through the
One A/D conversion module is connect with first microprocessor, first microprocessor and collector bluetooth connection, power supply and the first sensing
Device, first microprocessor connection；
Display terminal includes display fuselage, LCD screen and key, and LCD screen and key setting are shown in display fuselage surface
Show that device fuselage interior includes second sensor, RAM card, display power supply, the 2nd A/D conversion module, the second microprocessor and shows
Show device bluetooth, display power supply is connect with second sensor, the second microprocessor, second sensor and the 2nd A/D conversion module
Connection, the 2nd A/D conversion module, display bluetooth, RAM card, LCD screen are connect with the second microprocessor.
Further, collector external fuselage is stretched out in described first sensor one end, and the is equipped at the top of the one end stretched out
One hurricane globe, display external fuselage is stretched out in described second sensor one end, and the second hurricane globe is equipped at the top of the one end stretched out.
Further, the display fuselage interior further includes warning module, and warning module is connect with the second microprocessor.
Further, the first sensor, second sensor are condenser type sound pressure sensor.
A kind of vehicle braking frictional noise detection method, the second microprocessor is using the average method of energy, with continuously not
The A sound level of change indicates the sound level of the noise in the period, and noise sound level levels of contamination is divided into serious pollution, light contamination, just
Often, the calculation method of A sound level such as following formula:In formula, Leq--- equivalent continuous A sound level, dB；T——
The exposure duration of noise, s；LA--- the A sound level in time t；LeqIt is serious pollution more than 100dB, assert friction disc wear
Seriously；LeqBe more than 72dB lower than 100dB it is light contamination, assert friction plate mild wear；LeqIt is as normal lower than 72dB.
Second microprocessor carries out spectrum analysis to the drag friction noise signal of acquisition, preset by the second microprocessor
Algorithm carries out Fourier's Fast transforms to brake oil, finds out the dominant frequency of drag friction noise, Predistribution Algorithm calculation formula are as follows:Wherein, N is the sampling number of noise signal, and X [k] is frequency spectrum, and x [n] is one group of input sample；
When drag friction noise dominant frequency is in the section 1~15kHz, then normal brake application frictional noise can be regarded as, is then recognized more than this range
It is set to brake malfunctions.
Further, whenL eqWhen more than 100dB, LCD screen shows serious pollution and splashette, while warning module is alarmed；
WhenL eqWhen being more than 72dB lower than 100dB, LCD screen shows light contamination；WhenL eqWhen lower than 72dB, LCD screen is shown normally.
Compared with prior art, the present invention is a kind of portable vehicle drag friction noise level monitor, is rubbed for vehicle braking
It wipes noise monitoring and the diagnosis of brake fault provides possibility, also provide efficiency test hand for the research of vehicle braking frictional noise
Section.
Firstly, interior sensor realizes the monitoring of drag friction noise from driver's angle, vehicle outer sensor can be received
Collect the drag friction noise firsthand data, the two collaborative perception realizes more objective frictional noise detection, to examine or testing
The NVH performance of vehicle provides solution；It, can be real according to frictional noise, frictional vibration treated information such as frequency, amplitude
Existing drag friction noise failure diagnosis and early warning, improve the safety of driving.
Secondly, this equipment can realize the storage of frictional noise and vibration data, research drag friction noise and vibration are provided
Proficiency data necessary to dynamic.It is the essential tool for carrying out the academic research of drag friction noise for scientific research personnel；To vehicle
For master, acquisition data can be used for the right-safeguarding of brake manufacturer.
Again, noise and vibration sensor is easily installed, and whole system is wirelessly connected, and vehicle can be quick mounting to by being convenient for carrying
Body, the universal of equipment is laid a good foundation thus.
Detailed description of the invention
Fig. 1 is Noise Acquisition device structure chart of the present invention；
Fig. 2 is that the invention shows terminal structure figures；
Fig. 3 is Noise Acquisition device of the present invention and display terminal communication system block diagram；
Fig. 4 is acoustic pressure of the present invention judgement and service life early warning logic chart；
In figure: 1, Noise Acquisition device, the 101, first hurricane globe, 102, first sensor, 103, collector fuselage, 104, magnetic support；
2, display terminal, the 201, second hurricane globe, 202, second sensor, 203, display fuselage, 204, RAM card, 205, LCD screen
Curtain, 206, key；301, collector bluetooth, 302, first microprocessor, 303, collector power supply, the 305, the first A/D modulus of conversion
Block；401, display power supply, 402, warning module, the 405, the 2nd A/D conversion module, the 407, second microprocessor, 408, display
Device bluetooth.
Specific embodiment
The present invention will be further explained below with reference to the attached drawings.
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete
Site preparation description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other
Embodiment shall fall within the protection scope of the present invention.
The present invention includes Noise Acquisition device 1 and display terminal 2, and Noise Acquisition device 1 and display terminal 2 pass through bluetooth connection；
As shown in figures 1 and 3, Noise Acquisition device 1 includes collector fuselage 103 and magnetic support 104, collector fuselage 103 and magnetic support
104 connect, and include first sensor 102, collector power supply 303, first microprocessor 302, first inside collector fuselage 103
A/D conversion module 305 and collector bluetooth 301, first sensor 102 pass through the first A/D conversion module 305 and the first micro process
Device 302 connects, and first microprocessor 302 is connect with collector bluetooth 301, power supply 303 and first sensor 102, first micro- place
Device 302 is managed to connect；
As shown in Figures 2 and 3, display terminal 2 includes display fuselage 203, LCD screen 205 and key 206, LCD screen 205
Be arranged inside 203 surface of display fuselage, display fuselage 203 with key 206 includes second sensor 202, RAM card
204, display power supply 401, the 2nd A/D conversion module 405, the second microprocessor 407 and display bluetooth 408, display electricity
Source 401 is connect with second sensor 202, the second microprocessor 407, and second sensor 202 and the 2nd A/D conversion module 405 connect
It connects, the 2nd A/D conversion module 405, display bluetooth 408, RAM card 204, LCD screen 205 connect with the second microprocessor 407
It connects.
Collector fuselage 103 is micro- to protect circuit and control system, power supply 303 to be responsible for first sensor 102 and first
Processor 302 provides stable voltage output, and first sensor 102 passes through magnetic to collect brake oil, collector fuselage 103
Seat 104 is quickly fixed near brake disc, the analog signal that the first A/D conversion module 305 transmits the acquisition of first sensor 102
Digital data transmission is converted to first microprocessor 302, first microprocessor 302 transmits the acquired device bluetooth 301 of signal
To display terminal 2；
The outer brake disc of vehicle needs to detect brake oil, and same car is also required to detection brake oil, to reflect drag friction noise
Influence to human ear, therefore second sensor 202 is added in display terminal 2, display power supply 401 is respectively second sensor
202 and second microprocessor 407 power, the 2nd A/D conversion module 405 by second sensor 202 acquisition transmission analog signal
Digital data transmission is converted to the second microprocessor 407, meanwhile, display bluetooth 408 transmits the signal of Noise Acquisition device 1
To the second microprocessor 407.
As shown in figure 4, drag friction noise detecting method, the second microprocessor 407 method average using energy, with even
Continuing constant A sound level indicates the sound level of the noise in the period, and noise sound level levels of contamination is divided into serious pollution, slight dirty
Dye, normal, the calculation method of A sound level such as following formula:
In formula, Leq--- equivalent continuous A sound level, dB；The exposure duration of T --- noise, s；
LA--- the A sound level in time t；
LeqIt is serious pollution more than 100dB, assert that friction disc wear is serious；LeqIt is more than 72dB as slight lower than 100dB
Friction plate mild wear is assert in pollution；LeqIt is as normal lower than 72dB；
The drag friction noise signal of second 407 pairs of microprocessor acquisition carries out spectrum analysis, passes through the second microprocessor 407
Predistribution Algorithm carries out Fourier's Fast transforms to brake oil, finds out the dominant frequency of drag friction noise,
Predistribution Algorithm calculation formula are as follows:
Wherein, N is the sampling number of noise signal, and X [k] is frequency spectrum, and x [n] is one group of input sample；Above-mentioned calculation formula meeting
It is converted into code to edit and be downloaded in the second microprocessor 407 in Keil, can obtain drag friction noise master by operation
Frequently, when drag friction noise dominant frequency is in the section 1~15kHz, then normal brake application frictional noise can be regarded as, is more than this range
Then regard as brake malfunctions.Work as LeqWhen more than 100dB, LCD screen 205 shows serious pollution and splashette, while early warning
Module 402 is alarmed；Work as LeqWhen being more than 72dB lower than 100dB, LCD screen 205 shows light contamination；Work as LeqWhen lower than 72dB,
LCD screen 205 is shown normally.
It is obvious to a person skilled in the art that invention is not limited to the details of the above exemplary embodiments, Er Qie
In the case where without departing substantially from spirit or essential attributes of the invention, the present invention can be realized in other specific forms.Therefore, no matter
From the point of view of which point, the present embodiments are to be considered as illustrative and not restrictive, and the scope of the present invention is by appended power
Benefit requires rather than above description limits, it is intended that all by what is fallen within the meaning and scope of the equivalent elements of the claims
Variation is included within the present invention.Any reference signs in the claims should not be construed as limiting the involved claims.
The above, only presently preferred embodiments of the present invention, are not intended to limit the invention, all skills according to the present invention
Art any trickle amendment, equivalent replacement and improvement substantially to the above embodiments, should be included in technical solution of the present invention
Protection scope within.
Claims (6)
1. a kind of portable vehicle drag friction noise level monitor based on bluetooth, which is characterized in that including Noise Acquisition device (1)
With display terminal (2), Noise Acquisition device (1) and display terminal (2) pass through bluetooth connection；
Noise Acquisition device (1) includes collector fuselage (103) and magnetic support (104), and collector fuselage (103) and magnetic support (104) are even
Connect, include inside collector fuselage (103) first sensor (102), collector power supply (303), first microprocessor (302),
First A/D conversion module (305) and collector bluetooth (301), first sensor (102) pass through the first A/D conversion module (305)
It is connect with first microprocessor (302), first microprocessor (302) is connect with collector bluetooth (301), power supply (303) and the
One sensor (102), first microprocessor (302) connection；
Display terminal (2) includes display fuselage (203), LCD screen (205) and key (206), LCD screen (205) and key
(206) setting includes second sensor (202), RAM card inside display fuselage (203) surface, display fuselage (203)
(204), display power supply (401), the 2nd A/D conversion module (405), the second microprocessor (407) and display bluetooth
(408), display power supply (401) is connect with second sensor (202), the second microprocessor (407), second sensor (202)
Connect with the 2nd A/D conversion module (405), the 2nd A/D conversion module (405), display bluetooth (408), RAM card (204),
LCD screen (205) is connect with the second microprocessor (407).
2. a kind of portable vehicle drag friction noise level monitor based on bluetooth according to claim 1, feature exist
In collector fuselage (103) outside is stretched out in described first sensor (102) one end, and it is anti-to be equipped with first at the top of the one end stretched out
Fan housing (101), display fuselage (203) outside is stretched out in described second sensor (202) one end, and is equipped at the top of the one end stretched out
Second hurricane globe (201).
3. a kind of portable vehicle drag friction noise level monitor based on bluetooth according to claim 1, feature exist
In the internal display fuselage (203) further includes warning module (402), warning module (402) and the second microprocessor
(407) it connects.
4. a kind of portable vehicle drag friction noise level monitor based on bluetooth according to claim 1, feature exist
In the first sensor (102), second sensor (202) are condenser type sound pressure sensor.
5. a kind of vehicle braking frictional noise detection method, which is characterized in that
Second microprocessor (407) method average using energy indicates the noise in the period with continuous constant A sound level
Sound level, noise sound level levels of contamination is divided into serious pollution, light contamination, normally, the calculation method of A sound level such as following formula:
, in formula,L eq--- equivalent continuous A sound level, dB；T--- the exposure duration of noise, s；L A--- the A sound level in time t；
L eqIt is serious pollution more than 100dB, assert that friction disc wear is serious；L eqIt is more than 72dB as slight dirty lower than 100dB
Dye assert friction plate mild wear；L eqIt is as normal lower than 72dB；
Second microprocessor (407) carries out spectrum analysis to the drag friction noise signal of acquisition, passes through the second microprocessor
(407) Predistribution Algorithm carries out Fourier's Fast transforms to brake oil, finds out the dominant frequency of drag friction noise,
Predistribution Algorithm calculation formula are as follows:,
Wherein,NIt is the sampling number of noise signal,X[k] it is frequency spectrum,x[n] is one group of input sample；As drag friction noise master
Frequency can then regard as normal brake application frictional noise in the section 1 ~ 15kHz, then regard as brake more than this range and event occurs
Barrier.
6. a kind of vehicle braking frictional noise detection method according to claim 5, which is characterized in that whenL eqIt is more than
When 100dB, the serious pollution of LCD screen (205) display and splashette, while warning module (402) is alarmed；WhenL eqIt is super lower than 100dB
When crossing 72dB, LCD screen (205) shows light contamination；WhenL eqWhen lower than 72dB, LCD screen (205) display is normal.
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| CN201811228214.9A CN109443518A (en) | 2018-10-22 | 2018-10-22 | A kind of portable vehicle drag friction noise level monitor and method based on bluetooth |
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| CN201811228214.9A CN109443518A (en) | 2018-10-22 | 2018-10-22 | A kind of portable vehicle drag friction noise level monitor and method based on bluetooth |
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