CN101726743A - Vehicle active collision-preventing and positioning navigation device - Google Patents

Abstract

The invention discloses a vehicle active collision-preventing and positioning navigation device which comprises an ultrasonic ranging module, a GPS positioning navigation module, a main control unit module, a safe alarming module, an LCD display module and a vehicle safe control module, wherein the main control unit module comprises a singlechip A and a singlechip B which are communicated mutually through an interface, the safe alarming module and the LCD display module are connected with the singlechip A, and the ultrasonic ranging module, the GPS positioning navigation module and the vehicle safe control module are connected with the singlechip B. The device starts the brake under an emergence condition, thereby effectively reducing the probability of occurrence of traffic accidents, and ensuring the safety of passengers in vehicles and vehicles per se.

Description

Vehicle active collision-preventing and positioning navigation device

One, technical field:

This device is to gather the surrounding vehicles situation and analyze in the vehicle ' process, can enable protection scheme automatically when emergency condition is arranged, and avoids knocking into the back waiting the electronic product of traffic hazard generation.

Two, background technology:

Present automobile industry has entered the stage of high speed development, but the traffic hazard incidence also increases thereupon, solve safety problem in the running car except the propaganda that strengthens awareness of safety, installing safety device additional also is efficient and simple method, before 10 years, some advanced developed countries such as the U.S., Germany, Japan have begun the research and development to the vehicle active collision-preventing safety feature, but because blockade on new techniques and monopolization, at present China's similar products also seldom and major part be the Passive Defence device.

On distance measuring method ultrasound wave be easy to directional transmissions, good directionality, intensity easy to control, with advantages such as object being measured does not need directly to contact, be used as the desirable means of range finding.In the level gauging of precision, need to reach millimetre-sized measuring accuracy, but domestic ultrasonic ranging special IC all is to have only cm-level accuracy at present.

Three, summary of the invention:

For overcoming the above problems, the present invention has designed a kind of by ultrasonic ranging, the active vehicle safety convenience instrument that the GPS location combines.

The objective of the invention is to realize by following measure:

A kind of vehicle active collision-preventing and positioning navigation device, this device is by ultrasonic distance measuring module, GPS positioning navigation module, main control unit module, security alarm module, LCD display module, wireless communication module and vehicle safety control module constitute, described main control unit comprises by the Chip Microcomputer A of interface mutual communication and single-chip microcomputer B, security alarm module, wireless communication module and LCD display module are connected with Chip Microcomputer A, ultrasonic distance measuring module is connected with single-chip microcomputer B, and GPS positioning navigation module and vehicle safety control module also are connected with single-chip microcomputer B.

The vehicle safety control module comprises a motor, is provided with linkage part between the rotating shaft of this motor and the automobile service brake, and the starting switch of this motor is connected with the control end of single-chip microcomputer B.

This device also is provided with temperature sensor, and this temperature sensor is connected with Chip Microcomputer A by serial ports.

The present invention has following advantage compared to existing technology:

In the vehicle ' process, the data that ultrasonic distance measuring module is obtained, carry out to provide in real time after the compensation of acoustic wave propagation velocity the distance and the relative velocity of own car front vehicles with temperature sensor, and make prediction, the GPS positioning navigation module provides data to measure self position and speed with single-chip microcomputer, be transmitted to the equipment that can receive on every side by wireless device, when compatible mutually device is arranged on every side, can receive this information, by calculating 360 ° nearby vehicle situation, when this installed large-scale popularization use, surrounding vehicles was dodged in the range finding of GPS auxiliary ultrasonic.After this device obtains promoting, the supersonic range finder assistant GPS, early warning when realization will be caused danger, and startup brake in case of emergency, rather than as traditional when accident takes place, just taking measures, thereby effectively reduced the probability of happening of traffic hazard, the safety of member and vehicle itself in the service truck.This device can reach millimeter level measuring accuracy in theory.

Ultrasound wave is meant the vibrations mechanical wave of vibration frequency more than 20KHZ, ultrasound wave not only wavelength weak point, good directionality, can be the ray direction propagation, and run into the interface and just have remarkable reflection.These characteristics help selecting for use ultrasound wave to do medium, measure position, distance even the shape etc. of object.The hardware of the general total system of ultrasonic range finder is by sending part, Return Reception Dept. branch, temperature detection part, and phonological component and distance display and sound and light alarm are partly formed.The ultimate principle of ultrasonic ranging is that ultrasonic transmitter is constantly launched the .40kHz ultrasound wave, runs into barrier back reflection back reflective ripple, and ultrasonic receiver receives reflection wave signal, and changes it into electric signal.Measure the mistiming T that transmits and receives echo, obtain apart from S then.Under the situation of known speed C, be not difficult to draw:

$S=\frac{1}{2}\mathrm{CT}$

In the formula C one by one the ultrasound wave velocity of sound since ultrasound wave also be sound wave, so C is velocity of sound.Velocity of sound is:

$C=\sqrt{\mathrm{rp}/{\mathrm{\ρ}}_o}$

The γ adiabatic volume coefficient of gas (air is 1.4) one by one in the formula

P one by one gas air pressure can (sea level be 1.013x10 ⁶Pa)

(air is 1.29kg/m to gas density one by one ³)

For the 1mol air, quality is m, and volume is v, then density p ₀=m/v, so

$C=\sqrt{\mathrm{rp}/{\mathrm{\ρ}}_0}=\sqrt{\mathrm{rpv}/m}$

Gas for desirable has pV=RT,

R moles of gas Changshu one by one in the formula

T is absolute temperature one by one

Therefore:

Because γ, R, m are known constant, so velocity of sound C is only relevant with temperature T. if temperature-resistant, then sound speed and pressure in air has nothing to do.In 0 ℃ air, C0=331.5m/s.

Under arbitrary temp, have

Promptly

By can getting to the following formula actual analysis, 1 ℃ of the every rising of temperature, the velocity of sound increases to 0.607m/s, so

The experimental formula that can draw the velocity of sound and site environment temperature θ is:

C＝331.5+0.607θ

Like this, as long as record ultrasonic emitting and receive the mistiming T and the site environment temperature of echo, the distance between just can accurately calculating from the launching site to the barrier.

Ultrasonic sensor is installed in the front portion of automobile, and it receives and emission sensor close together, between stronger undesired signal is arranged easily.For prevent to survey phenomenon by mistake, on software, adopt to postpone reception technique, once improve the antijamming capability of system.

System initialization is at first finished the collection to temperature, determines the ultrasonic velocity under this temperature; If operating key is pressed, launch ultrasound wave, the T0 counter is counted simultaneously, receive reflection wave after T0 stop counting, calculate with this and transmit and receive hyperacoustic time interval; Calculate tested distance by numerical processor at last, send LCD display to show.

Apparatus of the present invention have added some new functions on existing brake technology, comprise safe early warning prompting and automatic emergency brake, allow automobile really realize intellectuality and hommization, reduce the generation of traffic hazard better, ensure driver's the personal safety and the safety of vehicle.

The security alarm module: when vehicle travelled on the straight way highway, the distance of front and back two cars can be measured by range finder module, and apparatus system will be judged the spacing that records then.If unsafe condition occurred, when promptly calculating back judgement car certificate less than the minimal security early warning distance according to the speed of a motor vehicle, spacing, apparatus system will be made corresponding indication immediately, and warning lamp lights, and reminds the car owner to make corresponding deceleration measure.

Vehicle safety control module: through remarkable normal reaction the time after (0.7 second-1 second), apparatus system has judged whether the deceleration measure once more, if still be in unsafe condition through judging, system will make the emergency brake order, send signal, finish deceleration, braking by the vehicle safety control module.

The GPS positioning navigation module is accepted each satellite its data, as position, launch time etc. by search of satellite.Because the position of satellite is accurately as can be known, in GPS observation, we can obtain the distance of satellite to receiver, utilize the range formula in the three-dimensional coordinate, utilize 3 satellites, just can form 3 equations, solve observation station the position (X, Y, Z).Navigation can add a falsh storage chip map is stored in the chip, can directly the position of calculating be shown when needing to get final product on map.

Domestic research range to active safety systems of vehicles is narrow; limitation is relatively big; and the vehicle active collision-preventing and positioning navigation device that we researched and developed on technology and protection effect aspect, can be described as the technical renovation that domestic vehicle safety is initiatively protected the field.

Four, description of drawings:

Fig. 1 is the theory diagram of this device;

Fig. 2 is the electrical schematic diagram of this device;

Fig. 3 is the synoptic diagram of vehicle safety control module;

Fig. 4 is the synoptic diagram between many vehicles;

Fig. 5 is the synoptic diagram that two workshop spacings belong to safe range more greatly;

Fig. 6 is the less dangerous hidden danger of two workshop spacings, the A car synoptic diagram that gives the alarm;

Fig. 7 is that two workshop spacings are very little dangerous, and the A car enters braking link synoptic diagram automatically;

Fig. 8 is two car exchange message synoptic diagram;

Fig. 9 is a running software process flow diagram of the present invention.

Five, embodiment:

In Fig. 1: (1) is Chip Microcomputer A, and (2) are single-chip microcomputer B, and the model of Chip Microcomputer A and single-chip microcomputer B is STC89C52; (3) be the LCD display module; (4) be the security alarm module; (5) be wireless communication module; (6) be ultrasonic distance measuring module; (7) GPS positioning navigation module; (8) vehicle safety control module.

Among Fig. 3: M is a gear; N is a motor; H is a pedal; G is a pull bar.

Each module interconnects:

1. in Fundamentals of Mono-Chip Computers figure, all with the CON1-CON7 mark, expression physically is connected on the P1.0-P1.7 of the P2.0-P2.7 of Chip Microcomputer A and single-chip microcomputer B, and two single-chip microcomputers are by this group interface intercom mutually (89c52 that single-chip microcomputer is stc).

2.LCD display module is connected with Chip Microcomputer A by the P1 mouth (8 bit data mouth) of a slice Chip Microcomputer A; Because this product does not need too much display interface, so the liquid crystal display of common 16*2 gets final product (as red sun 1602 series);

3. wireless communication module connects the serial ports of a slice Chip Microcomputer A, and wireless communication module TXD connects the RXD of Chip Microcomputer A, and wireless communication module RXD connects the TXD of Chip Microcomputer A; Wireless communication module supports that serial ports gets final product (as the product of zigbee series)

4. the warning of security alarm module (model ZJ22B) is by sound, light is formed, do not produce the reaction loudspeaker when two condition lines are 00, bulb is not worked, and reduction of speed or acceleration are wanted in the luminous signal of bulb in 01 o'clock, bulb was luminous in 10 o'clock, loudspeaker send the sound, and the situation is critical in signal, 11 o'clock bulb stroboscopics, loudspeaker send the sound, and signal starts the vehicle safety control module;

5.GPS positioning navigation module is connected to the serial ports of single-chip microcomputer B by serial ports; (GPS module TXD connects the RXD of Chip Microcomputer A, and GPS module RXD connects the TXD of single-chip microcomputer B) GPS i.e. on the market the GPS (as vast of heaven HOLUX) of band serial ports, in real time positional information is passed to single-chip microcomputer by crossing serial ports.

6. ultrasonic distance measuring module (model C J1) is connected to the mouth of single-chip microcomputer B with single line, and this module produces for single-chip microcomputer B when emission to interrupt, and single-chip microcomputer B picks up counting, and when receiving reflected signal, gives look-at-me of single-chip microcomputer B once more, stops timing.Ultrasonic wave module is by the ultrasonic emitting end, and the ultrasound wave receiving end is formed, and transmitting terminal sends ultrasonic signal, and receiving end is used to the reflection wave accepting to return.

7. temperature sensor (model DS18B20) connects single-chip microcomputer B with single line, gathers the temperature of external environment.

8. the vehicle safety control module is connected to delivery outlet of single-chip microcomputer with single line, produces a negative edge to the saltus step of this mouthful generation level and give braking in the time will braking, and makes automobile brake by brake when receiving brake signal.

As shown in Figure 3, the vehicle safety control module is installed a pull bar at former brake pedal place, gear and motor, and motor is by the signal controlling of main control unit, pull bar one side is provided with external tooth and gear matched, and gear is installed on the output shaft of motor or through speed reduction unit and is installed on the motor shaft.When main control unit sent the emergency brake signal, motor rotated, motor driven gear, and the gear driven pull bar along the pedal brake direction pedal of leaving behind, is finished the action of emergency brake.When signal relief, pedal rebounds automatically.

As shown in Figure 4, the synoptic diagram between many vehicles:

(1) is wireless transmission

(2) be the ultrasonic reflections synoptic diagram

Fig. 5 is the synoptic diagram that two workshop spacings belong to safe range more greatly

Va is the speed of a motor vehicle of A car;

Vb is the speed of a motor vehicle of B car;

Fig. 6 is the less dangerous hidden danger of two workshop spacings, the A car synoptic diagram that gives the alarm;

Va is the speed of a motor vehicle of A car;

Vb is the speed of a motor vehicle of B car;

Fig. 7 is that two workshop spacings are very little dangerous, and the A car enters the braking link automatically;

Ws: be the Braking mode alarm;

Vb: be the B car speed of a motor vehicle;

Fig. 8 is two car exchange messages;

Fig. 9 is the running software process flow diagram of package unit.

The course of work of vehicle active collision-preventing and positioning navigation device of the present invention:

Among Fig. 1:

At first the mistiming of measuring the pulse emission and accepting,, obtain the outer temperature of car, utilize experimental formula by temperature sensor by ultrasonic distance measuring module

C＝331.5+0.607θ

C is a temperature for velocity of sound θ in the formula

The formulate of range finding is: L=C * T

In the formula L for measure apart from length;

C is the aerial velocity of propagation of ultrasound wave;

T is measuring distance mistiming of propagating (T is transmitted into half of time of reception numerical value).

Draw the velocity of sound under the current environment, and then pass through formula

Vc＝L/td；

Vc is the relative speed of a motor vehicle;

L is two spacings;

Td: be the time interval;

Draw the distance with the place ahead barrier, the difference of getting two times result again draws the relative velocity with barrier, utilizes formula and GPS draws current location by the location by two secondary data:

Vx＝(Sx1-Sx2)/td；

Vy＝(Sy1-Sy2)/td；

Vx: be oneself speed on the latitude direction;

Vy: be oneself speed on longitudinal;

Sx: be the position on self latitude direction;

Sy: be oneself position on longitudinal;

Draw current vehicle speed and direction and outwards propagate with wireless communication module, when compatible mutually equipment is only received can by own GPS Position And Velocity that obtains and the data that receive relatively draw two workshops apart from relative velocity, compatible equipment around this device detects is not for a long time, work with the GPS auxiliary ultrasonic, otherwise, but when doing enough compatible equipments, use the mode of ultrasound wave assistant GPS to work, can draw the travel situations of vehicle in the peripheral 360 degree scopes, carry out mutual coordination between each vehicle by wireless communication module, can prevent and prevent the dangerous situation that may occur.

Among Fig. 5:

Ultrasonic distance measuring module detects the A car and the B car travels in the safe spacing scope, and the data that GPS issues single-chip microcomputer are normal by drawing speed after calculating, and do not send any warning;

Among Fig. 6:

Ultrasonic distance measuring module detect data that the too little but GPS of A car and B following distance issues single-chip microcomputer by after calculating speed is normal, send the too near alarm of distance;

Among Fig. 7:

Ultrasonic distance measuring module detects that spacing reaches hazard level between two cars, and the data that GPS issues single-chip microcomputer by after calculating the speed of a motor vehicle does not have downward trend, this device forces automobile to brake reduction of speed automatically;

Fig. 8 is two workshop radio communications;

Second step is mainly with each parameter zero clearing among Fig. 9; T1 in the 3rd step and the 4th step, T2 obtains by the Timer of single-chip microcomputer inside; The formula that provides in the explanation of V by Fig. 1 in the 5th step draws; The 8th the step in Sn by | Pn-P1| ∠ (Pn-P1) obtains; N is predefined value in the 9th step, draws by test statistics; Program is returned after executing one time, carries out circulation of the 3rd step formation;

The course of work of the present invention may further comprise the steps:

Step 1.

At first GPS, ultrasonic wave module are opened in device energising back, each parameter of temperature detecting module and initialization,

Step 2. receive that ultrasonic distance measuring module sends by the T1 mouth as single-chip microcomputer B first when interrupting, open the timer of single-chip microcomputer B, current time, T1 was designated as 0, and the value of reading temperature sensor is designated as tem, and timing one adds 1 (being used for writing down the single-chip microcomputer time) to variable T

Step 3. is when receiving the interruption that ultrasonic wave module sends for the second time, and single-chip microcomputer reads variable T and saves as T2

By the * (T2-T1)/2 of formula S=(3315+0.6*tem)

Calculate two workshops apart from Sw

Step 4. serial ports by single-chip microcomputer B then reads the data computation that GPS sends and draws current automobile self present position coordinate P1;

Step 5. is opened wireless transport module, Chip Microcomputer A is asked by wireless the transmission towards periphery, the content that receives is given the PORT1 mouth of single-chip microcomputer B by the PORT2 oral instructions, single-chip microcomputer B distinguishes each automobile by the identification code in the content that receives, and the vehicle number n that receives of statistics and they position coordinate P2, P3, P4.....Pn subtract each other respectively at own position P1 vector and draw relative distance S2, S3.....Sn separately.

Step 6. with n and N (value that user oneself sets) relatively when n greater than N be think peripheral most of car all have with this device mutually the distance that obtains by ultrasonic distance measuring module of compatible equipment revise S2 that wireless communication module and GPS module draw the distance of car in the Sn over against oneself, if n is not more than N and then draws S2 distance of car over against oneself in the Sn by wireless communication module and GPS module and revise the distance that ultrasonic distance measuring module obtains, draw the dead ahead car apart from S;

The relative moving speed v that relatively draws two workshops of step 7.S and the S ' that last time collected shows by Chip Microcomputer A S and v with 1206 liquid crystal display;

Step 8. single-chip microcomputer B draws hazard index W gives Chip Microcomputer A with the PORT1 oral instructions PORT2 mouth by v and S, when Chip Microcomputer A receives hazard index relatively it with the size of reference value when discovery w during greater than Ws single-chip microcomputer B send out brake signal to the vehicle safety control module, if w greater than W2 less than Ws by Chip Microcomputer A to the alarm signal of safety alarm module sounding light, if w greater than W3 less than W2, Chip Microcomputer A turns back to step 2 and constitutes circulation to the luminous alarm signal of safety alarm module.

Claims (3)

1. vehicle active collision-preventing and positioning navigation device, this device is by ultrasonic distance measuring module, GPS positioning navigation module, main control unit module, security alarm module, LCD display module, wireless communication module and vehicle safety control module constitute, described main control unit comprises by the Chip Microcomputer A of interface mutual communication and single-chip microcomputer B, security alarm module, wireless communication module and LCD display module are connected with Chip Microcomputer A, ultrasonic distance measuring module is connected with single-chip microcomputer B, and GPS positioning navigation module and vehicle safety control module also are connected with single-chip microcomputer B.

2. vehicle active collision-preventing and positioning navigation device according to claim 1, it is characterized in that: described vehicle safety control module comprises a motor, be provided with linkage part between the rotating shaft of this motor and the automobile service brake, the starting switch of this motor is connected with the control end of single-chip microcomputer B.

3. vehicle active collision-preventing and positioning navigation device according to claim 1 and 2 is characterized in that: this device also is provided with temperature sensor, and this temperature sensor is connected with Chip Microcomputer A by serial ports.

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