CN104442758A - Automobile anticollision system based on ultrasonic ranging device with temperature compensation - Google Patents

Automobile anticollision system based on ultrasonic ranging device with temperature compensation Download PDF

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Publication number
CN104442758A
CN104442758A CN201410736762.8A CN201410736762A CN104442758A CN 104442758 A CN104442758 A CN 104442758A CN 201410736762 A CN201410736762 A CN 201410736762A CN 104442758 A CN104442758 A CN 104442758A
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CN
China
Prior art keywords
module
unit
super sonic
timing
distance
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
CN201410736762.8A
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Chinese (zh)
Inventor
谢敏富
胡清华
高娟
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
SUZHOU OUBORI AUTOMATION TECHNOLOGY Co Ltd
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SUZHOU OUBORI AUTOMATION TECHNOLOGY Co Ltd
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Priority to CN201410736762.8A priority Critical patent/CN104442758A/en
Publication of CN104442758A publication Critical patent/CN104442758A/en
Withdrawn legal-status Critical Current

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Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60QARRANGEMENT OF SIGNALLING OR LIGHTING DEVICES, THE MOUNTING OR SUPPORTING THEREOF OR CIRCUITS THEREFOR, FOR VEHICLES IN GENERAL
    • B60Q9/00Arrangements or adaptations of signal devices not provided for in one of the preceding main groups, e.g. haptic signalling
    • B60Q9/008Arrangements or adaptations of signal devices not provided for in one of the preceding main groups, e.g. haptic signalling for anti-collision purposes
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60TVEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T7/00Brake-action initiating means
    • B60T7/12Brake-action initiating means for automatic initiation; for initiation not subject to will of driver or passenger
    • B60T7/22Brake-action initiating means for automatic initiation; for initiation not subject to will of driver or passenger initiated by contact of vehicle, e.g. bumper, with an external object, e.g. another vehicle, or by means of contactless obstacle detectors mounted on the vehicle
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S15/00Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
    • G01S15/02Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems using reflection of acoustic waves
    • G01S15/06Systems determining the position data of a target
    • G01S15/08Systems for measuring distance only
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S15/00Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
    • G01S15/88Sonar systems specially adapted for specific applications
    • G01S15/93Sonar systems specially adapted for specific applications for anti-collision purposes

Abstract

The invention discloses an automobile anticollision system based on an ultrasonic ranging device with temperature compensation. The automobile anticollision system comprises a microcontroller module, as well as an ultrasonic transmission module, an ultrasonic reception module, a temperature measurement module, a display module, an alarm module, a braking deceleration module and a power supply module which are connected with the microcontroller module, wherein the microcontroller module comprises a timing unit, a computing unit, a parameter comparison unit and a control unit; and the ultrasonic reception module comprises an ultrasonic receiver, an amplifying circuit, a detecting circuit and a comparison shaping circuit which are sequentially connected. The system has low cost and high precision can effectively avoid influence of ambient temperature change on ranging accuracy, greatly improves measurement accuracy of an ultrasonic ranging system and can further effectively avoid traffic accidents by precise calculation of a following distance.

Description

A kind of anti-collision system for automobile of supersonic range finder based on having temperature compensating
Technical field
The present invention relates to a kind of ultrasonic ranging system, particularly relating to a kind of anti-collision system for automobile of supersonic range finder based on having temperature compensating, belonging to automobile collision preventing field.
Background technology
Super sonic is a kind of machinery concussion in elastic medium, and it is that its frequency is at more than 20kHz caused by the concussion source contacted with medium.Because hypracoustic speed is much smaller relative to the light velocity, its interval travel time is just detected than being easier to, and be easy to beam transmission, good directionality, intensity controls well, thus utilize ultrasonic ranging to have very important purposes in a lot of distance measurement application, comprise non-destructive test, process measurement, robot measurement and location, and fluid level measurement etc.
In atmosphere, under normal temperature, hypracoustic propagation speed is 334m/s, but its propagation speed is by the impact of the factor such as temperature, humidity in air, and wherein temperature influence is comparatively large, and as temperature often raises 1 DEG C, the velocity of sound will increase about 0.6m/s.Therefore in identical interval measurement distance, because the wave propagation time is identical, the velocity of sound under different temperatures is different, so finally cause the distance measured unequal, in the exigent situation of range measurement accuracy, must measure temperature and compensate, to avoid temperature on the impact of survey precision.Ultrasonic testing processed often relatively rapidly, convenient, calculating is simple, be easy to realization, and survey precision is high.
Along with expanding economy, transportation is become increasingly prosperous, but is difficult to catch up with due to the hardware such as road condition, transport administration, add drive overtake other vehicles, principle that to go out that car is deserted, mistake estimates spacing etc. subjective, the traffic accident of collision is mutually occurred again and again.The essential measure addressed this problem is to install and can find range from motion tracking to the automobile in advancing, self-stopping device in danger range.
Such as application number is that the one of " 201120488173.4 " is based on hypracoustic car bump protection control system, comprise collision-prevention controller, the ultrasonic range finder be connected with collision-prevention controller, car speed sensor, brake controller and engine controller, the drg be connected with brake controller, the solenoid fuel injection valve be connected with engine controller.This utility model measures the relative distance information and relative velocity that obtain car and preceding object thing in real time by ultrasonic range finder, and in conjunction with speed information, car retardation or braking is controlled after judging, thus greatly reduce the collision probability of car and obstacle, alleviate the impact severity of car and obstacle, effectively ensure that chaufeur and other people life safety, whole system structure is simple, reliability is high, practicality is good, but not yet considers the impact of temperature and survey precision needs to be improved further.
And for example application number is a kind of automobile anti-collision alarm system based on ultrasonic ranging of " 201210178595.0 ".It comprises AT89C2051 control module, ultrasonic distance measuring module, alarm module, display module and power module.AT89C2051 control module is transferred to when the distance detected is converted into level signal by ultrasonic distance measuring module, the signal received carries out processing and compares with the maximum range value of setting by AT89C2051 control module, if this distance is less than the maximum range value of setting, AT89C2051 control module will send instruction to alarm module, make alarm sounds remind driver, distance value is shown by display module simultaneously.This invention meets the requirement of generally closely finding range, and cost is lower, has good cost performance, can be widely used in small distance range finding, robot detects, in vehicle backing radar, but not yet considers the impact of temperature and survey precision needs to be improved further.
Summary of the invention
Technical matters to be solved by this invention provides a kind of anti-collision system for automobile of supersonic range finder based on having temperature compensating for the deficiency of background technology, it has low cost, high precision, and the impact of variation of ambient temperature on range accuracy can be effectively prevent, improve the survey precision of ultrasonic ranging system effectively, and then the generation of traffic accident can be efficiently avoid by accurate Calculation spacing.
The present invention is for solving the problems of the technologies described above by the following technical solutions:
A kind of anti-collision system for automobile of supersonic range finder based on having temperature compensating, comprise micro controller module and connected super sonic transmitter module, super sonic receiver module, temperature-measuring module, display module, alarm module, brake deceleration module and power module, described micro controller module comprises timing unit, calculating unit, parameter comparison unit and control unit, described super sonic receiver module comprise connect successively super sonic Receiver, amplifying circuit, detecting circuit, compare shaping circuit;
Wherein, super sonic transmitter module, sends a timing actuation signal to timing unit for launching super sonic simultaneously;
Super sonic receiver module, for sending a timing danger signal to timing unit when receiving super sonic for the first time simultaneously;
Temperature-measuring module, for Real-time Collection ambient temperature;
Timing unit, is receiving the time between the timing actuation signal of super sonic transmitter module transmission and the timing danger signal of super sonic receiver module transmission for calculating, and then the time will be uploaded to calculating unit;
Calculating unit, for calculating the distance s of distance obstacle according to v=331.4+0.61T, s=vt/2, is shown by display module simultaneously in real time;
Wherein, t is the time difference between the timing actuation signal of super sonic transmitter module transmission and the timing danger signal of super sonic receiver module transmission, and T is actual environment temperature, and v is the velocity of sound under current environment;
Parameter comparison unit, carries out analysis for the distance of distance obstacle that calculates according to calculating unit and setting value and contrasts, if the time in that the distance of distance obstacle being less than safety distance, then send a signal to control unit;
Control unit, gives the alarm for the signal control alarm unit sent according to parameter comparison unit, simultaneously driving brake deceleration unit.
As a kind of further preferred version of anti-collision system for automobile of supersonic range finder based on having temperature compensating of the present invention, the safety distance of described distance obstacle is 30m.
As a kind of further preferred version of anti-collision system for automobile of supersonic range finder based on having temperature compensating of the present invention, described micro controller module is AVR series monolithic.
As a kind of further preferred version of anti-collision system for automobile of supersonic range finder based on having temperature compensating of the present invention, described display module is LCD display.
As a kind of further preferred version of anti-collision system for automobile of supersonic range finder based on having temperature compensating of the present invention, described alarm module is acousto-optic warning unit.
The present invention adopts above technical scheme compared with prior art, has following technique effect:
1, structure of the present invention simple, there is low cost, high precision, cost are lower and survey precision is high;
2, the present invention can effectively avoid variation of ambient temperature on the impact of range accuracy, improves the survey precision of ultrasonic ranging system effectively;
3, the present invention can remind motorist in time by accurate Calculation spacing, efficiently avoid the generation of traffic accident.
Accompanying drawing explanation
Fig. 1 is structure principle chart of the present invention.
Detailed description of the invention
Below in conjunction with accompanying drawing, technical scheme of the present invention is described in further detail:
As shown in Figure 1, a kind of anti-collision system for automobile of supersonic range finder based on having temperature compensating, comprise micro controller module and connected super sonic transmitter module, super sonic receiver module, temperature-measuring module, display module, alarm module, brake deceleration module and power module, described micro controller module comprises timing unit, calculating unit, parameter comparison unit and control unit, described super sonic receiver module comprise connect successively super sonic Receiver, amplifying circuit, detecting circuit, compare shaping circuit;
Wherein, super sonic transmitter module, sends a timing actuation signal to timing unit for launching super sonic simultaneously;
Super sonic receiver module, for sending a timing danger signal to timing unit when receiving super sonic for the first time simultaneously;
Temperature-measuring module, for Real-time Collection ambient temperature;
Timing unit, is receiving the time difference between the timing actuation signal of super sonic transmitter module transmission and the timing danger signal of super sonic receiver module transmission for calculating, and then the time difference will be uploaded to calculating unit;
Calculating unit, for calculating the distance s of distance obstacle according to v=331.4+0.61T, s=vt/2, is shown by display module simultaneously in real time;
Wherein, t is the time between the timing actuation signal of super sonic transmitter module transmission and the timing danger signal of super sonic receiver module transmission, and T is actual temperature, and v is the velocity of sound under current environment;
Parameter comparison unit, carries out analysis for the distance of distance obstacle that calculates according to calculating unit and setting value and contrasts, if the time in that the distance of distance obstacle being less than safety distance, then send a signal to control unit;
Control unit, gives the alarm for the signal control alarm unit sent according to parameter comparison unit, simultaneously driving brake deceleration unit.
Wherein, the safety distance of described distance obstacle is 30m, and described micro controller module is AVR series monolithic, and described display module is LCD display, and described alarm module is acousto-optic warning unit.
In atmosphere, under normal temperature, hypracoustic propagation speed is 334m/s, but its propagation speed is by the impact of the factor such as temperature, humidity in air, and wherein temperature influence is comparatively large, and as temperature often raises 1 DEG C, the velocity of sound will increase about 0.6m/s.Therefore in identical interval measurement distance, because the wave propagation time is identical, the velocity of sound under different temperatures is different, so finally cause the distance measured unequal, in the exigent situation of range measurement accuracy, must measure temperature and compensate, to avoid temperature on the impact of survey precision.Native system selects DS18B20 temperature sensor as temperature survey, error-compensating apparatus, and only need an I/O mouth line with micro controller system exchange message, its power supply can derive from single-chip processor i/o mouth data line, and without the need to additional power supply.Under different temperatures, the temperature variant relation of propagation speed is as follows in atmosphere for super sonic: in v=331.4+0.61T formula, and T is actual temperature (DEG C), and v is the velocity of sound under current environment, and unit is m/s.
Alarm unit: be made up of binary pair, driving circuit and toy trumpet.When following distance is 30m, micro controller system is to binary pair signal, makes binary pair set produce a set of pulses, by driving circuit, makes toy trumpet send chimes of doom, and when being greater than 30m, trigger reset, stops producing pulse.
Brake deceleration unit: be made up of K switch and self-actuating brake speed reduction gearing, when driver thinks that necessity uses self-actuating brake speed reduction gearing, close switch K.When following distance is less than 20m, micro controller system provides a signal, starts self-actuating brake speed reduction gearing, prevents collision.
AVR single chip has prefetched instruction function, namely when an execution instruction, in advance next instruction is got into, and call instruction can be performed within a clock period; Multiple accumulator type, data processing speed is fast; AVR single chip has 32 general purpose working registers, and being equivalent to has 32 overpasss, can fast passing; Response time is fast.AVR single chip has multiple fixing interrupt vector entry address, can respond interruption fast; AVR single chip power consumption is low.For typical power consumption situation, be 100nA when WDT closes, be more suitable for battery powered application apparatus; Minimum 1.8 V of some devices get final product work; AVR single chip security performance is good.
Ultrasonic transmit circuit is sent by micro controller system mouth Direct driver super sonic, and super sonic acceptor circuit mouth is connected with micro controller system, and the mouth of micro controller system is connected with display circuit input end.Micro controller system, in TO moment transmit square waves, starts timer simultaneously and starts timing, and after receiving echo, generation one is negative jumps to singlechip interruption mouth, and micro controller system response interrupt routine, timer stops counting.Computing time, difference can obtain the time t that super sonic is propagated in medium, just can calculate distance thus.
The square wave of 40kHz drives super sonic emitting head to launch super sonic by AVR single chip, the sinusoidal waveform of 40kHz is received after reflection by super sonic Receiver, owing to decaying when sound wave is propagated in atmosphere, so the waveforms amplitude received is lower, through acceptor circuit amplification, shaping, finally export a negative saltus step, input micro controller system.Crystal oscillator due to Single Chip Microcomputer (SCM) system is 12M crystal oscillator, so can only produce the square-wave signal that the semiperiod is 12 μ s or 13 μ s, frequency is respectively 41.67kHz and 38.46kHz.Native system has selected the latter when programming.The signal received be added to BG1, BG2 composition dual-stage amplifier on amplify.The magnification factor of every grade of amplifier is 70 times.Amplifying signal obtains the signal after demodulation by detecting circuit.Used herein is IN4148 detector diode, the direct current signal i.e. capacitance voltage between two diodes of output.This acceptor circuit structure is simple, and better performances, manufacture difficulty is little.
The present invention relates to a kind of anti-collision system for automobile of supersonic range finder based on having temperature compensating, in order to improve the measuring precision and system stability further, hardware adds temperature sensor temperature measurement circuit, take the preset way combined with medium temperature survey of the velocity of sound to revise the velocity of sound, reduce the impact of temperature traverse on range accuracy.Improve the survey precision of ultrasonic ranging system effectively.Motorist can be reminded in time by accurate Calculation spacing, efficiently avoid the generation of traffic accident.
Those skilled in the art of the present technique are understandable that, unless otherwise defined, all terms used herein (comprising technical term and scientific terminology) have the meaning identical with the general understanding of the those of ordinary skill in field belonging to the present invention.Should also be understood that those terms defined in such as general dictionary should be understood to have the meaning consistent with the meaning in the context of prior art, unless and define as here, can not explain by idealized or too formal implication.
Above embodiment is only and technological thought of the present invention is described, can not limit protection scope of the present invention with this, and every technological thought proposed according to the present invention, any change that technical scheme basis is done, all falls within scope.By reference to the accompanying drawings embodiments of the present invention are explained in detail above, but the present invention is not limited to above-mentioned embodiment, in the ken that those of ordinary skill in the art possess, makes a variety of changes under can also or else departing from the prerequisite of present inventive concept.

Claims (5)

1. one kind based on the anti-collision system for automobile of supersonic range finder with temperature compensating, it is characterized in that: comprise micro controller module and connected super sonic transmitter module, super sonic receiver module, temperature-measuring module, display module, alarm module, brake deceleration module and power module, described micro controller module comprises timing unit, calculating unit, parameter comparison unit and control unit, described super sonic receiver module comprise connect successively super sonic Receiver, amplifying circuit, detecting circuit, compare shaping circuit;
Wherein, super sonic transmitter module, sends a timing actuation signal to timing unit for launching super sonic simultaneously;
Super sonic receiver module, for sending a timing danger signal to timing unit when receiving super sonic for the first time simultaneously;
Temperature-measuring module, for Real-time Collection ambient temperature;
Timing unit, is receiving the time between the timing actuation signal of super sonic transmitter module transmission and the timing danger signal of super sonic receiver module transmission for calculating, and then the time will be uploaded to calculating unit;
Calculating unit, for calculating the distance s of distance obstacle according to v=331.4+0.61T, s=vt/2, is shown by display module simultaneously in real time;
Wherein, t is the time difference between the timing actuation signal of super sonic transmitter module transmission and the timing danger signal of super sonic receiver module transmission, and T is actual environment temperature, and v is the velocity of sound under current environment;
Parameter comparison unit, carries out analysis for the distance of distance obstacle that calculates according to calculating unit and setting value and contrasts, if the time in that the distance of distance obstacle being less than safety distance, then send a signal to control unit;
Control unit, gives the alarm for the signal control alarm unit sent according to parameter comparison unit, simultaneously driving brake deceleration unit.
2. a kind of anti-collision system for automobile of supersonic range finder based on having temperature compensating according to claim 1, is characterized in that: the safety distance of described distance obstacle is 30m.
3. a kind of anti-collision system for automobile of supersonic range finder based on having temperature compensating according to claim 1, is characterized in that: described micro controller module is AVR series monolithic.
4. a kind of anti-collision system for automobile of supersonic range finder based on having temperature compensating according to claim 1, is characterized in that: described display module is LCD display.
5. a kind of anti-collision system for automobile of supersonic range finder based on having temperature compensating according to claim 1, is characterized in that: described alarm module is acousto-optic warning unit.
CN201410736762.8A 2014-12-05 2014-12-05 Automobile anticollision system based on ultrasonic ranging device with temperature compensation Withdrawn CN104442758A (en)

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Application Number Priority Date Filing Date Title
CN201410736762.8A CN104442758A (en) 2014-12-05 2014-12-05 Automobile anticollision system based on ultrasonic ranging device with temperature compensation

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104965205A (en) * 2015-05-27 2015-10-07 苏州合欣美电子科技有限公司 Ultrasonic ranging apparatus based on temperature compensation
CN104990715A (en) * 2015-07-14 2015-10-21 南京航空航天大学 Novel tyre sinkage quantity measuring device
CN105522997A (en) * 2015-12-21 2016-04-27 东北大学 Intelligent safe early warning system and method for wagon turning
CN106114214A (en) * 2016-06-16 2016-11-16 成都易云知科技有限公司 A kind of intelligent car-backing CAS

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
王红云: "基于超声波测距的倒车雷达系统设计", 《自动控制与仪器仪表》 *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104965205A (en) * 2015-05-27 2015-10-07 苏州合欣美电子科技有限公司 Ultrasonic ranging apparatus based on temperature compensation
CN104990715A (en) * 2015-07-14 2015-10-21 南京航空航天大学 Novel tyre sinkage quantity measuring device
CN105522997A (en) * 2015-12-21 2016-04-27 东北大学 Intelligent safe early warning system and method for wagon turning
CN106114214A (en) * 2016-06-16 2016-11-16 成都易云知科技有限公司 A kind of intelligent car-backing CAS

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Application publication date: 20150325

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