CN201314953Y - Ultrasonic ranging system - Google Patents

Ultrasonic ranging system Download PDF

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Publication number
CN201314953Y
CN201314953Y CNU2008201228212U CN200820122821U CN201314953Y CN 201314953 Y CN201314953 Y CN 201314953Y CN U2008201228212 U CNU2008201228212 U CN U2008201228212U CN 200820122821 U CN200820122821 U CN 200820122821U CN 201314953 Y CN201314953 Y CN 201314953Y
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China
Prior art keywords
ultrasonic
ultrasound wave
receiving
reception module
module
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Expired - Fee Related
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CNU2008201228212U
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Chinese (zh)
Inventor
张爱军
曹伟
徐兴建
吴建军
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BEIJING JINGYEDA DIGITAL SYSTEM TECHNOLOGY Co Ltd
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BEIJING JINGYEDA DIGITAL SYSTEM TECHNOLOGY Co Ltd
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Abstract

The utility model discloses an ultrasonic ranging system. The technical scheme comprises an ultrasonic transceiver module and a singlechip-controlled operation module, wherein the ultrasonic transceiver module is used to transmit ultrasonic waves to a measured obstacle and receive the reflected waves returned by the measured obstacle; and the singlechip-controlled operation module which is connected with the ultrasonic transceiver module is used to control the ultrasonic transceiver module to receive and transmit ultrasonic waves, acquire the time elapsed from the transmission to reception of ultrasonic waves and compute the distance between the ultrasonic transceiver module and the measured obstacle according to the time and a configured temperature parameter. After the technical scheme is adopted, the distribution of vacant parking spaces in a parking lot can be obtained, so that parking resources can be reasonably allocated and utilized, and thereby, traffic pressure can be eased to a certain degree.

Description

A kind of ultrasonic ranging system
Technical field
The utility model relates to the ultrasonic sensor technical field, is specifically related to a kind of ultrasonic ranging system.
Background technology
At present, people's living standard improves constantly, and the owning amount of vehicle is also in continuous increase, so supporting parking facility is also in constantly increase and perfect.Like this, the demand to intelligent transportation, parking management is a hot issue.The means of parking stall statistical management are also along with demand is constantly upgraded in the parking lot, but can in time count in the parking lot, and the method for each parking stall parking situation is also few.In parking stall statistical system few in number, more commonly, when vehicle enters the parking lot, an electronic card is got in the capital, the vehicle management personnel judge by the quantity of card whether untapped vacant parking stall is arranged in the parking lot, but there is certain drawback in the managing parking field by this method, because the driver is before driving the parking lot into, only know and also leave room (because if Occupied in the parking lot, then do not issue electronic card), but the particular location that can not accurately know vacant parking stall where, just needs own Bian Kaibian to look for, and will waste a lot of time like this.
The utility model content
In view of above-mentioned existing in prior technology problem, the purpose of this utility model provides a kind of ultrasonic ranging system, can in time grasp the vacant parking stall distribution situation in parking lot, the utilization of reasonable distribution parking resource, thus alleviate certain traffic pressure.
The purpose of this utility model is achieved through the following technical solutions:
A kind of ultrasonic ranging system comprises: be used for to tested barrier emission ultrasound wave, receive the ultrasonic transmission/reception module of the reflection wave that returns from tested barrier; Link to each other with described ultrasonic transmission/reception module, be used to control described ultrasonic transmission/reception module transmitting-receiving ultrasound wave, gather ultrasound wave from being transmitted into the time that reception is experienced, and calculate the Single-chip Controlling computing module of distance between ultrasonic transmission/reception module and the tested barrier according to the temperature parameter in described time and the ranging parameters that configures.
Further, described system also comprises: link to each other with described Single-chip Controlling computing module, be used for the distance between described ultrasonic transmission/reception module and the tested barrier is sent to the data transmission module of central controller.
Further, described ultrasonic transmission/reception module specifically comprises: be used for sending and receiving hyperacoustic ultrasonic probe; Link to each other with described ultrasonic probe, be used to drive described ultrasonic probe and launch hyperacoustic ultrasonic emitting driving circuit to tested barrier; Be used for reflection wave that described ultrasonic probe is received, convert the ultrasound wave receiving circuit of the life time signal that described Single-chip Controlling computing module can receive to.
Further, described ultrasonic probe adopts transmitting-receiving integrated ultrasonic probe, perhaps adopts the split type ultrasonic probe of transmitting-receiving.
Further, described ultrasound wave receiving circuit adopts infrared receiving demodulation circuit.
Further, described Single-chip Controlling computing module specifically comprises: link to each other with described ultrasonic transmission/reception module, be used to drive the emission driver element of described ultrasonic emitting driving circuit; Be used to receive receiving element through the life time signal after the described ultrasound wave receiving circuit conversion; Be used for real-time measures ambient temperature, and adjust the thermostat unit of the temperature parameter in the ranging parameters according to environment temperature; Be used to gather described ultrasound wave from being transmitted into the time that reception is experienced, and calculate the metrics calculation unit of distance between ultrasonic transmission/reception module and the tested barrier according to the described time in conjunction with the temperature parameter in the described ranging parameters.
Further, described thermostat unit adopts the DS18b20 digital temperature sensor.
The beneficial effects of the utility model:
1, the technical scheme that provides by above-mentioned the utility model as can be seen, system applies described in the utility model is in the parking lot, whether according to the vertical range of the device that collects and ground or roof, thereby it is occupied to judge this parking stall; And the parking information of each parking stall gathered, promptly obtain the distribution situation of whole empty vehicle parking position of parking lot, thus wagon flow inside and outside the parking lot is carried out correct guidance, improve traffic administration intelligent degree, alleviate certain traffic pressure;
2, ultrasonic ranging system adopts the ultrasonic transmission/reception circuit, has guaranteed the stable of range finding, and circuit structure simply is easy to produce in batches;
3, ultrasonic ranging system is integrated temperature sensor can the real-time regulated ranging parameters, makes native system can use indoor and outdoor parking lot under the various environment temperatures.
Description of drawings
Fig. 1 is the simplified structure synoptic diagram of system described in the utility model;
Fig. 2 is the ultrasonic transmit circuit schematic diagram of system described in the utility model;
Fig. 3 is the ultrasound wave receiving circuit schematic diagram of system described in the utility model;
Fig. 4 is the signal processing flow in the ultrasound wave receiving circuit of system described in the utility model;
Fig. 5 is the oscillogram at A, B in the signal processing flow in the ultrasound wave receiving circuit of system described in the utility model, C, D place;
Fig. 6 is the workflow diagram of Single-chip Controlling computing module in the system described in the utility model;
Fig. 7 is the circuit theory diagrams of data transmission module in the system described in the utility model.
Embodiment
A kind of ultrasonic ranging system described in the utility model as detection means, produces and receives ultrasound wave by ultrasonic sensor with ultrasound wave.Ultrasonic sensor is to utilize the principle of piezoelectric effect that electric energy and ultrasound wave are transformed mutually, and promptly when emission was hyperacoustic, converting electrical energy was launched ultrasound wave; When receiving echo, convert ultrasonic vibration to electric signal.It is the mechanical wave of 40kHZ that the utility model adopts frequency, launch by ultrasonic sensor, after bumping against barrier (ground or roof), form reflection wave, after reflection wave is received by ultrasonic sensor, the mistiming that transmits and receives by calculating, obtain the distance of ultrasonic sensor and barrier, judge in proper order whether the parking stall in the parking lot uses.
As shown in Figure 1, a kind of ultrasonic ranging system of the utility model embodiment comprises: be used for to tested barrier emission ultrasound wave, receive the ultrasonic transmission/reception module S11 of the reflection wave that returns from tested barrier; Link to each other with described ultrasonic transmission/reception module, be used to control described ultrasonic transmission/reception module transmitting-receiving ultrasound wave, gather ultrasound wave from being transmitted into the time that reception is experienced, and calculate the Single-chip Controlling computing module S12 of distance between ultrasonic transmission/reception module and the tested barrier according to the temperature parameter in described time and the ranging parameters that configures.
This system also comprises: link to each other with described Single-chip Controlling computing module, be used for the distance between described ultrasonic transmission/reception module and the tested barrier is sent to the data transmission module S13 of central controller.
The ultrasonic transmission/reception module specifically comprises: be used for sending and receiving hyperacoustic ultrasonic probe S111; Link to each other with described ultrasonic probe, be used to drive described ultrasonic probe and launch hyperacoustic ultrasonic emitting driving circuit S112 to tested barrier; Be used for reflection wave that described ultrasonic probe is received, convert the ultrasound wave receiving circuit S113 of the life time signal that described Single-chip Controlling computing module can receive to.
This ultrasonic sensor S111 can adopt the split type ultrasonic probe of transmitting-receiving; Also can adopt transmitting-receiving integrated ultrasonic probe.But transmitting-receiving integrated ultrasonic probe has certain inertia, and transmission also leaves certain remained shock after finishing, and this remained shock produces voltage signal equally through transducer, and return signal is caught by the system that upset, thus influence range finding result.Adopt the split type ultrasonic probe of transmitting-receiving can effectively avoid the problem of inertia.So the utility model is is preferably received and dispatched split type ultrasonic probe.
Ultrasonic emitting driving circuit S112 (as shown in Figure 2): utilize single-chip microcomputer IO mouth to send 40kHzTTL (life span) signal and drive PNP triode Q1, carry out electric current and amplify the lifting driving force, drive an inductive transformer by Q1 afterwards, carry out the adjustment of voltage amplitude, finally drive ultrasonic sensor transmitting terminal (Transmiter among the figure), produce the ultrasound wave of the 40kHz of certain intensity.
The parameter of ultrasonic transmit circuit, will be in the scope that the ultrasonic probe parameter allows, cooperate the sensitivity of receiving circuit to carry out careful adjustment, to guarantee that emissive power can not ether by force or too: the invalid signals that can cause sound wave repeatedly to reflect to form too by force, disturb the reception of normal echo to handle; Then can not guarantee too normal finding range (echo before returning receiving transducer just in the propagation medium air decay serious, cause the ultrasonic sensor receiving end can't reliable reception, the reliable triggering, thereby influence stability even do not have received signal.
The utility model embodiment is through repeatedly experiment, the circuit parameter shown in the preferred table 1.Table 1 is that described system adopts transmitting-receiving split probe, model NU40C16T/R-1, and concrete electric parameter is as follows:
Part number (dash number) NU40C16T-1 NU40C16R-1
Construction (structure) Open structure type Open structure type
Using Method (using method) Transmitter Receiver
Center frequency (centre frequency) 40.0±1.0KHz 40.0±1.0KHz
Sound pressure level (sound pressure level) 114dB min. ----------------
Sensitivity (sensitivities) ---------------- -68dB min.
Capacitance (electric capacity) 2500Pf±20% 2500Pf±20%
Maximum input voltage (maximum input voltage) 20Vrms 20Vrms
Directivity (directivity) 60°±15°(-6dB) 60°±15°(-6dB)
Operating temperature (working temperature) -20℃~+70℃ -20℃~+70℃
Storage Temperature (storing temperature) -40℃~+85℃ -40℃~+85℃
Above-mentioned parameter can guarantee reliably working in the investigative range of 3 meters of range measurement systems, and the sound wave that transmission range surpasses 6 meters (3 meters * 2) can effectively decay, and avoids repeatedly the influence of reflection wave to system.
The parameter of ranging parameters shown in the table 1 except Operating temperature (working temperature) and Storage Temperature (storing temperature) by the decision of circuit hardware parameter, determined in design process; Will be for ranging parameters Operatingtemperature relevant (working temperature) and Storage Temperature (storing temperature) by adjusting after the real-time measures ambient temperature with temperature.
This ultrasound wave receiving circuit S113 adopts infrared receiving demodulation circuit.This ultrasound wave receiving circuit S113 (as shown in Figure 3): the millivolt level feeble signal that reception ultrasonic sensor receiving end need be exported be amplified, filtering (getting rid of 40kHz undesired signal in addition), detection again, integration, shaping afterwards, form the TTL signal that single-chip microcomputer can receive at last, thereby obtain the time that echo arrives.In the ultrasound wave receiving circuit flow process of signal Processing as shown in Figure 4, Fig. 5 is the waveform at node A, B among Fig. 4, C, D place; Through processing the low level among the waveform D obtain, be the useful signal that finally obtains, formally according to this low level, record and computing that the moment that echo is arrived carries out.
System described in the utility model is when using, owing to design the receiving circuit more complicated voluntarily, can adopt the infrared receiving demodulation circuit similar to the ultrasound wave receiving circuit, finish a series of functions that receive ultrasound wave and handle, preferred model is the infrared receiving demodulation chip of CX20106 in the application.There are certain similarity in infrared receiving demodulation circuit and ultrasound wave receiving circuit, all are to carry out a series of processing to the feeble signal about 40kHz, finally obtain the useful signal on the 40kHz carrier wave.Concrete principle is as shown in Figure 3: among the figure in the left side Receiver on limit be the receiving end of ultrasonic sensor, U3 is the infrared receiving demodulation chip of CX20106, final TTL trigger pip has the Pin7 output of U3, " 40kHz R " signal on the right of just the last figure.
Described Single-chip Controlling computing module S12 specifically comprises: link to each other with described ultrasonic transmission/reception module, be used to drive the emission driver element S121 of described ultrasonic emitting driving circuit; Be used to receive receiving element S122 through the life time signal after the described ultrasound wave receiving circuit conversion; Be used for real-time measures ambient temperature, and adjust the thermostat unit S123 of the temperature parameter in the ranging parameters according to environment temperature; Be used to gather described ultrasound wave from being transmitted into the time that reception is experienced, and calculate the metrics calculation unit S124 of distance between ultrasonic transmission/reception module and the tested barrier according to the described time in conjunction with the temperature parameter in the described ranging parameters.
Described metrics calculation unit S124 adopts transit time method TOF (time of flight) to calculate the distance between ultrasonic sensor and the barrier.At first measuring ultrasound wave runs into barrier and returns the time of being experienced from being transmitted into, multiply by hyperacoustic speed again and just obtain two times sound source and the distance D between the barrier, formula is: D=vt/2, v are that propagation rate (with the environment temperature relevant) computing formula of sound wave in medium is as follows:
v t = v 0 T 273.15 = v 0 1 + t 273.15 ;
Wherein, v 0=331.45m/s, T are environment absolute temperature, and t is relative temperature (unit be degree centigrade).
Described thermostat unit S123 can adopt DS18b20 digital temperature sensor measures ambient temperature when using.This sensor bulk little (triode size), effectively temperature-measuring range is-55~125 ℃, and can guarantee in-10~85 ℃ temperature range ± 0.5 ℃ precision, satisfies the requirement of system fully.
Shown in Figure 6, be Single-chip Controlling arithmetic element workflow diagram: before each range finding, master routine all will be measured environment temperature, to adjust and range finding associated temperature parameter.Because system described in the utility model is applied in underground, open parking ground, belongs to outdoor environment.In the north, various places, each season, outdoor range of temperature can reach-20~50 ℃, and at this moment the variation range of the velocity of sound is 319~360.51m/s.As seen, be absolutely necessary according to the adjustment ranging parameters.
The circuit of described data transmission module S13 is as shown in Figure 7: utilize 485 bussing techniques, each ultrasonic ranging terminal can be range finding result separately, is sent to the central controller outside the hundreds of rice to 1000 meter accurately, carries out unified processing.The communications protocol that matching design is rigorous under the communication speed at 9.6kbps, can be finished gathering of 1000 range finding end messages in 5 seconds.In addition, each range finding terminal is before inserting 485 buses, and transient state stabilivolt (TVS pipe) also in parallel is over the ground protected, and has effectively avoided interference that long bus brings and the thunderbolt destruction that may occur.
The above; it only is the preferable embodiment of the utility model; but protection domain of the present utility model is not limited thereto; anyly be familiar with those skilled in the art in the technical scope that the utility model discloses; the variation that can expect easily or replacement all should be encompassed within the protection domain of the present utility model.Therefore, protection domain of the present utility model should be as the criterion with the protection domain of claim.

Claims (7)

1, a kind of ultrasonic ranging system is characterized in that, comprising: be used for to tested barrier emission ultrasound wave, receive the ultrasonic transmission/reception module of the reflection wave that returns from tested barrier; Link to each other with described ultrasonic transmission/reception module, be used to control described ultrasonic transmission/reception module transmitting-receiving ultrasound wave, gather ultrasound wave from being transmitted into the time that reception is experienced, and calculate the Single-chip Controlling computing module of distance between ultrasonic transmission/reception module and the tested barrier according to described time and the temperature parameter that configures.
2, system according to claim 1, it is characterized in that, described system also comprises: link to each other with described Single-chip Controlling computing module, be used for the distance between described ultrasonic transmission/reception module and the tested barrier is sent to the data transmission module of central controller.
3, system according to claim 1 is characterized in that, described ultrasonic transmission/reception module specifically comprises: be used for sending and receiving hyperacoustic ultrasonic probe; Link to each other with described ultrasonic probe, be used to drive described ultrasonic probe and launch hyperacoustic ultrasonic emitting driving circuit to tested barrier; Be used for reflection wave that described ultrasonic probe is received, convert the ultrasound wave receiving circuit of the life time signal that described Single-chip Controlling computing module can receive to.
4, system according to claim 3 is characterized in that, described ultrasonic probe adopts transmitting-receiving integrated ultrasonic probe, perhaps adopts the split type ultrasonic probe of transmitting-receiving.
5, system according to claim 3 is characterized in that, described ultrasound wave receiving circuit adopts infrared receiving demodulation circuit.
According to claim 1 or 3 described systems, it is characterized in that 6, described Single-chip Controlling computing module specifically comprises: link to each other with described ultrasonic transmission/reception module, be used to drive the emission driver element of described ultrasonic emitting driving circuit; Be used to receive receiving element through the life time signal after the described ultrasound wave receiving circuit conversion; Be used for real-time measures ambient temperature, and adjust the thermostat unit of the temperature parameter in the ranging parameters according to environment temperature; Be used to gather described ultrasound wave from being transmitted into the time that reception is experienced, and calculate the metrics calculation unit of distance between ultrasonic transmission/reception module and the tested barrier according to the described time in conjunction with the temperature parameter in the described ranging parameters.
7, system according to claim 6 is characterized in that, described thermostat unit adopts the DS18b20 digital temperature sensor.
CNU2008201228212U 2008-09-27 2008-09-27 Ultrasonic ranging system Expired - Fee Related CN201314953Y (en)

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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101870295A (en) * 2010-06-24 2010-10-27 武汉理工大学 Derailing detector for large road maintenance vehicle
CN103262575A (en) * 2010-12-20 2013-08-21 Nec卡西欧移动通信株式会社 Oscillator device and electronic instrument
CN105629215A (en) * 2014-10-27 2016-06-01 同致电子科技(厦门)有限公司 Vehicle ultrasonic sensor correction method and system
CN107748365A (en) * 2017-09-15 2018-03-02 南京轩世琪源软件科技有限公司 A kind of real-time update indoor locating system based on ultrasonic ranging
CN108535733A (en) * 2018-03-08 2018-09-14 芜湖泰领信息科技有限公司 Ultrasonic evadible system
CN109932723A (en) * 2019-03-28 2019-06-25 国网新疆电力有限公司喀什供电公司 Inside transformer structure detection device and application method
WO2019119655A1 (en) * 2017-12-22 2019-06-27 重庆物奇科技有限公司 Depth sensor, detection system, and method for controlling transmission power of sensor
CN110749888A (en) * 2019-12-20 2020-02-04 广州赛特智能科技有限公司 Distance measurement method based on ultrasonic distance measurement system
CN110940986A (en) * 2019-12-25 2020-03-31 广东奥迪威传感科技股份有限公司 Ultrasonic detection device and ultrasonic detection system
CN113900106A (en) * 2021-09-01 2022-01-07 淮南师范学院 Scanning type distance measurement obstacle avoidance system based on LabVIEW

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101870295A (en) * 2010-06-24 2010-10-27 武汉理工大学 Derailing detector for large road maintenance vehicle
CN103262575A (en) * 2010-12-20 2013-08-21 Nec卡西欧移动通信株式会社 Oscillator device and electronic instrument
CN103262575B (en) * 2010-12-20 2017-05-31 日本电气株式会社 Oscillator device and electronic instrument
CN105629215A (en) * 2014-10-27 2016-06-01 同致电子科技(厦门)有限公司 Vehicle ultrasonic sensor correction method and system
CN105629215B (en) * 2014-10-27 2018-09-25 同致电子科技(厦门)有限公司 A kind of vehicle ultrasonic sensor bearing calibration and system
CN107748365A (en) * 2017-09-15 2018-03-02 南京轩世琪源软件科技有限公司 A kind of real-time update indoor locating system based on ultrasonic ranging
WO2019119655A1 (en) * 2017-12-22 2019-06-27 重庆物奇科技有限公司 Depth sensor, detection system, and method for controlling transmission power of sensor
CN108535733A (en) * 2018-03-08 2018-09-14 芜湖泰领信息科技有限公司 Ultrasonic evadible system
CN109932723A (en) * 2019-03-28 2019-06-25 国网新疆电力有限公司喀什供电公司 Inside transformer structure detection device and application method
CN110749888A (en) * 2019-12-20 2020-02-04 广州赛特智能科技有限公司 Distance measurement method based on ultrasonic distance measurement system
CN110940986A (en) * 2019-12-25 2020-03-31 广东奥迪威传感科技股份有限公司 Ultrasonic detection device and ultrasonic detection system
CN113900106A (en) * 2021-09-01 2022-01-07 淮南师范学院 Scanning type distance measurement obstacle avoidance system based on LabVIEW

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CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20090923

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