CN202486313U - Ultrasonic ranging sensor - Google Patents
Ultrasonic ranging sensor Download PDFInfo
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- CN202486313U CN202486313U CN2012201084617U CN201220108461U CN202486313U CN 202486313 U CN202486313 U CN 202486313U CN 2012201084617 U CN2012201084617 U CN 2012201084617U CN 201220108461 U CN201220108461 U CN 201220108461U CN 202486313 U CN202486313 U CN 202486313U
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Abstract
The utility model discloses an ultrasonic ranging sensor. The ultrasonic ranging sensor comprises a central processing unit (CPU) module, a signal processing module and a receiving-sending ultrasonic transducer which are mutually connected. The ultrasonic ranging sensor adopts general-purpose devices, after a series of amplifying, compensating, filtering and shaping ultrasonic ranging signals and the like through the signal processing module which is internally designed, and the ultrasonic ranging sensor can enable an ultrasonic fault detection precision to achieve a millimeter range and a detection distance to be enlarged under the circumstance of not using an expensive special ultrasonic ranging chip. In addition, stability of products is improved by circuit design, and therefore the ultrasonic ranging sensor has good application prospect.
Description
Technical field
The utility model relates to field of measuring technique, is specifically related to a kind of ultrasonic ranging sensor.
Background technology
In recent years, the ultrasonic sensor technology had been widely used in industrial automation range finding, correction, measurement of discharge, survey wind speed etc.Because traditional ultrasonic ranging sensor precision under bad working environment is low, stability and poor reliability can't be applied to the automatic control field of high request.At present external special-purpose ultrasonic ranging chip can be worked under the rugged environment situation, and precision is high, and stability and reliability are high, but be difficult to buying and cost too high, be difficult for realizing.
The utility model content
The purpose of the utility model is low in order to overcome ultrasonic ranging sensor traditional in prior art precision under bad working environment, and stability and poor reliability can't be applied to the automatic control field of high request.At present external special-purpose ultrasonic ranging chip can be worked under the rugged environment situation, and precision is high, and stability and reliability are high, but be difficult to buying and cost too high, be difficult for the problem that realizes.
In order to solve the problems of the technologies described above, the technical scheme that the utility model adopted is:
A kind of ultrasonic ranging sensor comprises CPU module, signal processing module and transceiver ultrasonic transducer; Said CPU module comprises CPU and second source circuit; Each circuit is connected in said second source circuit and the CPU module; It is characterized in that: said CPU module also comprises schmidt trigger circuit, echoed signal output driving circuit, ultrasonic emitting driving circuit and automatic gain control Driver Circuit; The trigger pip output terminal of outside range measurement system main frame is connected with the trigger pip input end of the schmidt trigger circuit of CPU module; The output terminal of said schmidt trigger circuit is connected with the first external interrupt port of CPU; The echoed signal output terminal of CPU is connected with the echoed signal input end of outside range measurement system main frame through the echoed signal output driving circuit; The gain control signal output terminal of CPU is connected with automatic gain control circuit in being arranged on signal processing module through the automatic gain control Driver Circuit, and the ultrasonic emitting drive signal output terminal of CPU is connected with transducer booster driving circuit in being arranged on signal processing module through the ultrasonic emitting driving circuit.
Aforesaid ultrasonic ranging sensor; It is characterized in that: said signal processing module also comprises impedance matching and pre-amplification circuit, secondary bandpass filtering amplifying circuit, active full-wave rectifier filter circuit and wave shaping comparator circuit; The terminals of said transceiver ultrasonic transducer are connected with the input end of impedance matching and pre-amplification circuit and the output terminal of transducer booster driving circuit respectively; The output terminal of impedance matching and pre-amplification circuit is connected through the input end of said automatic gain control circuit with secondary bandpass filtering amplifying circuit; The output terminal of secondary bandpass filtering amplifying circuit is connected with the input end of active full-wave rectifier filter circuit; The output terminal of active full-wave rectifier filter circuit is connected with the input end of wave shaping comparator circuit, and the output terminal of wave shaping comparator circuit is connected with the second external interrupt port of said CPU.
Aforesaid ultrasonic ranging sensor; It is characterized in that: said signal processing module also is provided with emitter follower type mid-point voltage driving circuit, said emitter follower type mid-point voltage driving circuit respectively with impedance matching and pre-amplification circuit, secondary bandpass filtering amplifying circuit and active full-wave rectifier filter circuit in the in-phase input end of operational amplifier be connected.
Aforesaid ultrasonic ranging sensor is characterized in that: the said automatic gain control circuit that is arranged in the signal processing module, and between said impedance matching and pre-amplification circuit and secondary bandpass filtering amplifying circuit.
Aforesaid ultrasonic ranging sensor; It is characterized in that: the said wave shaping comparator circuit that is arranged in the signal processing module is provided with comparer; The triggering reference voltage terminal of said comparer is connected with the positive pole of diode, and the negative pole of said diode is connected with the output terminal of said emitter follower type mid-point voltage driving circuit.
The beneficial effect of the utility model is: the utility model still adopts general-purpose device; Signal processing module through autonomous Design to the ultrasonic ranging signal amplify, after a series of processing such as compensation, filtering, shaping; Under the situation of the ultrasonic ranging chip that does not use the high special use of price; Can make the ultrasonic listening precision reach millimeter level, detection range increase, also improve the stability and the reliability of product, have a good application prospect through circuit design.
Description of drawings
Fig. 1 is the system chart of the ultrasonic ranging sensor of the utility model.
Fig. 2 is the software design process flow diagram of the ultrasonic ranging sensor of the utility model.
Fig. 3 is the ultrasonic ranging sensor of the utility model and the interface schema of outside range measurement system main frame.
Fig. 4 is the signal timing diagram that the outside range measurement system host analysis of the utility model obtains.
Fig. 5 is the circuit theory diagrams of the signal processing module of the utility model.
Fig. 6 is the circuit theory diagrams of the CPU module of the utility model.
Embodiment
To combine Figure of description below, the utility model will be further described.
As shown in Figure 1; A kind of ultrasonic ranging sensor; Comprise CPU module, signal processing module and transceiver ultrasonic transducer; The trigger pip output terminal Clock port of outside range measurement system main frame is connected with the input end Clock port of the schmidt trigger circuit of CPU module; The output terminal of said schmidt trigger circuit is connected with the first external interrupt INT0 port of CPU; The echoed signal output terminal out3 port of CPU is connected with the input end of echoed signal output driving circuit; Echoed signal output driving circuit output terminal Echo port is connected with the echoed signal input end Echo port of outside range measurement system main frame, and the gain control signal output terminal out2 port of CPU is connected with the input end of automatic gain control Driver Circuit, and the output terminal of automatic gain control Driver Circuit is connected with the interior automatic gain control circuit of signal processing module; The ultrasonic emitting drive signal output terminal out1 port of CPU is connected with the input end of ultrasonic emitting driving circuit, and the output terminal of ultrasonic emitting driving circuit is connected with the interior transducer booster driving circuit of signal processing module.
The terminals of said transceiver ultrasonic transducer respectively with signal processing module in impedance matching and the input end of pre-amplification circuit and the output terminal of transducer booster driving circuit be connected; The output terminal of impedance matching and pre-amplification circuit is connected with the input end of automatic gain control circuit; The output terminal of automatic gain control circuit is connected with the input end of secondary bandpass filtering amplifying circuit; The output terminal of secondary bandpass filtering amplifying circuit is connected with the input end of active full-wave rectifier filter circuit; The output terminal of active full-wave rectifier filter circuit is connected with the input end of wave shaping comparator circuit, and the output terminal of wave shaping comparator circuit is connected with the second external interrupt INT1 port of CPU.
Said signal processing module also is provided with the emitter follower type mid-point voltage driving circuit and first power circuit; Said emitter follower type mid-point voltage driving circuit respectively with impedance matching and pre-amplification circuit, secondary bandpass filtering amplifying circuit and active full-wave rectifier filter circuit in the in-phase input end of operational amplifier be connected, first power circuit is connected with each circuit in the signal processing module.
The said automatic gain control circuit that is arranged in the signal processing module is between impedance matching and pre-amplification circuit and secondary bandpass filtering amplifying circuit.
The said wave shaping comparator circuit that is arranged in the signal processing module is provided with comparer; The triggering reference voltage terminal of said comparer is connected with the positive pole of diode, and the negative pole of said diode is connected with the output terminal of said emitter follower type mid-point voltage driving circuit.
Wherein the CPU module is used for the input and output of the various signals of control and treatment; Ultrasonic transducer is used to send ultrasonic signal and receives the ultrasonic echo signal; The second source circuit is used for each circuit of ultrasonic ranging sensor provides WV; Schmidt trigger circuit is used for the range finding trigger pip that outside range measurement system main frame sends is carried out shaping; Because the range finding trigger pip level that the outside range measurement system main frame of different manufacturers sends is also inconsistent; Dying is designed to Schmitt trigger circuit the mode of operation of wide logic level, and promptly incoming level is higher than 2/3U
BBe high level, incoming level is lower than 1/3 U
BBe low level, U
BSupply voltage for this ultrasonic ranging sensor; Schmitt trigger circuit is made up of the precision comparator chip, and its associated electrical resistance obtains through accurate calculating; The ultrasonic emitting driving circuit adopts triode or mos pipe that the ultrasonic emitting signal that CPU exports is amplified; Be used for the ultrasonic transducer booster driving circuit in the drive signal processing module, guarantee that the transceiver ultrasonic transducer can send ultrasonic signal; The transducer booster driving circuit adopts miniature transformer that ultrasonic emitting ripple signal is boosted to several hectovolts; The ultrasonic transducer that drives transceiver sends ultrasonic signal; The power supply of miniature transformer primary side need have good Filtering Processing, guarantees that the ultrasound wave of launching is stable; The automatic gain control Driver Circuit is controlled the automatic gain control Driver Circuit by CPU according to the pairing detection range in different time territory; Near more according to detection range; Signal attenuation is big more; The low more principle of gain is exported the base stage of the triode in the automatic gain control circuit of different level in the signal processing module, thus the gain amplifier of control echoed signal; The driving force of considering CPU is limited; And echo output signal polarity will meet this 2 factors that require of outside range measurement system main frame; Driving element in the echoed signal output driving circuit adopts withstand voltage triode or mos higher, that output current is bigger to manage; With the Echo echo-pulse input end of ultrasonic echo signal conveys, improve reliability of products to outside range measurement system main frame.
Said signal processing module is provided with impedance matching and pre-amplification circuit, automatic gain control circuit, secondary bandpass filtering amplifying circuit, active full-wave rectifier filter circuit and wave shaping comparator circuit, and said impedance matching and pre-amplification circuit, automatic gain control circuit, secondary bandpass filtering amplifying circuit and active full-wave rectifier filter circuit, wave shaping comparator circuit are connected successively.Said impedance matching and pre-amplification circuit adopt the linear discharge circuit of anti-phase input form, and its input signal is given by the transceiver ultrasonic transducer, and the signal after amplifying outputs to automatic gain control circuit.Though the impedance matching property of this circuit and transceiver ultrasonic transducer is poor slightly; But common-mode rejection ratio is high, can effectively suppress the fluctuation of supply voltage, improves the precision of measurement data; Loss as for the signal amplification factor that causes because of impedance matching property difference can remedy in follow-up circuit; Here the operational amplifier of selecting for use is put and is selected low noise for use, the linear amplifier of wide bandwidth, and the cutoff frequency of amplifier decuples frequency of operation.
Said automatic gain control circuit is because whole ultrasonic ripple distance measuring sensor signal processing module is very big to the enlargement factor of echoed signal; Automatic gain control circuit residing position in whole signal processing circuit seems very important; It directly has influence on the signal to noise ratio (S/N ratio) and the stability of whole signal processing circuit, and it is best that automatic gain control circuit is positioned between impedance matching and pre-amplification circuit and the secondary bandpass filtering amplifying circuit effect.The input signal of automatic gain control circuit comes from the output terminal of impedance matching and pre-amplification circuit; Ultrasonic echo signal after circuit adopts triode common emitter (or mos pipe common source) circuit to impedance matching and pre-amplification circuit amplification carries out voltage division processing; Its damping capacity to signal is controlled by CPU; Signal after automatic gain control circuit is handled outputs to secondary bandpass filtering amplifying circuit to carry out frequency-selecting and amplifies, and automatic gain control circuit can effectively reduce the blind area of finding range.
Said secondary bandpass filtering amplifying circuit adopts the multiple feedback active filter of linear amplifier as unlimited gain amplifier; Characteristics are that wave filter frequency, bandwidth and gain are prone to transfer; And adopt two-stage can improve the signal gain amplifier of whole signal processing circuit greatly at frequency of operation point; Effectively improve antijamming capability and the increase detection range of circuit to other sound wave; Its input signal comes from the output of automatic gain control circuit, and the output signal offers active full-wave rectifier filter circuit and carries out the full-wave rectifier filter signal Processing.
Said active full-wave rectifier filter circuit is made up of accurate full-wave rectifying circuit and π type RC filtering circuit, can make circuit avoid diode dead band voltage and indicial response to the influence of rectification output, has realized accurate full-wave rectification and high sensitivity.The input signal of this circuit comes from secondary bandpass filtering amplifying circuit, and the output signal connects the signal input part of the wave shaping comparator circuit of back.
Said wave shaping comparator circuit is that the end at comparer promptly triggers reference voltage and adopts the mode from the mid-point voltage of motion tracking amplifier; Be used as the triggering reference voltage of ultrasonic echo signal by diode substantially constant characteristics of pressure drop when the forward conduction; In case the triggering reference voltage of this end of comparer was also followed change automatically when the mid-point voltage of amplifier produced fluctuation because of certain reason; Thereby make the ultrasonic echo voltage of signals through active full-wave rectifier filter circuit is remained unchanged with the difference that triggers reference voltage, improved the distance accuracy of entire circuit.
In-phase input end need provide a 1/2Vcc mid-point voltage ability operate as normal (Vcc is the WV of linear amplifier) when said emitter follower type mid-point voltage driving circuit was worked owing to the operational amplifier of single power supply in this circuit; Whether stablizing of mid-point voltage is most important; For stability and the distance accuracy that improves entire circuit; Can improve the load capacity of its mid-point voltage again through one emitter follower circuit to the 1/2Vcc behind the electric resistance partial pressure; Thereby guaranteed the stability of mid-point voltage, improved the stability and the distance accuracy of entire circuit.
In conjunction with shown in Figure 2; The concrete engineering process of the ultrasonic ranging sensor of the utility model is following: when outside range measurement system main frame provides the Clock port of an initial range finding trigger pip to schmidt trigger circuit; After the schmidt trigger circuit level conversion, send the first external interrupt INT0 port of the CPU processor of CPU module to; CPU controls the ultrasonic emitting driving circuit after receiving this signal at once, and the ultrasonic transducer that drives transceiver sends a string ultrasonic signal, and CPU controls automatic gain control circuit through the automatic gain control Driver Circuit simultaneously; Controlling automatic gain control circuit according to the pairing detection range in different time territory decays to echoed signal; Detection range is near more, and signal attenuation is big more, and it is low more to gain., ultrasound wave produces echo when running into object; Echo is detected by the ultrasonic transducer of transceiver; The echoed signal that detects triggers the second external interrupt INT1 port of the CPU of CPU module after signal processing module is handled; CPU promptly produces the pulse signal (being the ultrasonic echo response signal) of a fixed pulse width, and the Echo end through the echoed signal output driving circuit outputs to outside range measurement system main frame Echo input end again, supplies outside range measurement system main frame to use.The mistiming computed range of range finding Clock trigger pip that outside range measurement system main frame sends according to himself and the ultrasound wave Echo echoed signal returned by the ultrasonic ranging sensor.
The principle of work of the echoed signal that above-mentioned signal processing module is handled is following: the feeble signal by ultrasonic transducer detected is at first amplified echoed signal through impedance matching and pre-amplification circuit; The signal of microvolt level is zoomed into the signal of millivolt level; Send into automatic gain control circuit then; Automatic gain control circuit is actual to be a signal attenuator that receives CPU control in the CPU module; Concrete control method is: the damping capacity to signal is inversely proportional to detected hyperacoustic echo distance, and promptly the nearlyer damping capacity of ultrasonic echo signal distance is big more.The ultrasonic echo signal is through arriving secondary bandpass filtering amplifying circuit behind the automatic gain control circuit, this circuit amplifies the filtering clutter to carrying out frequency-selecting to the ultrasonic echo signal.Ultrasonic echo signal after frequency-selecting is amplified is sent into the envelope signal that active full-wave rectifier filter circuit extracts the ultrasonic echo signal again, sends out the ultrasonic echo interrupt trigger signal that a CPU in the CPU module can discern through the wave shaping comparator circuit at last.Detailed process is following: a termination of the comparer of wave shaping comparator circuit triggers reference voltage; Comparator toggles when the intensity of ultrasonic echo signal surpasses this triggering reference voltage; Export the external interrupt INT1 port of the CPU of a control signal in the CPU module; CPU promptly produces the pulse signal (being the ultrasonic echo response signal) of a fixed pulse width; Echo end through the echoed signal output driving circuit outputs to outside range measurement system main frame Echo input end again, supplies outside range measurement system main frame to use.As shown in Figure 3, the ultrasonic ranging sensor of the utility model and the interface of outside range measurement system main frame, wherein+U
B,-U
BPort is the supply voltage of this ultrasonic ranging sensor; The Clock port is the range finding trigger pip that outside range measurement system main frame sends; The Echo port is the ultrasonic echo signal of ultrasonic ranging sensor output; The signal timing diagram that its analysis obtains is as shown in Figure 4, and outside range measurement system main frame comes computed range according to the mistiming echo time of the Echo ultrasonic echo signal that himself sends Clock range finding trigger pip and returned by the ultrasonic ranging sensor.
Fig. 5 is the circuit theory diagrams of practical implementation of the signal processing module of the utility model, and Fig. 6 is the circuit theory diagrams of the practical implementation of CPU module.
In sum; The utility model still adopts general-purpose device; Signal processing module through autonomous Design amplifies, after a series of processing such as compensation, filtering, shaping, under the situation of the ultrasonic ranging chip that does not use the high external special use of price, can make the ultrasonic listening precision reach millimeter level (below 1 millimeter), detection range increases the ultrasonic ranging signal; Also improved the stability of product, had a good application prospect through circuit design.
More than show and described ultimate principle, principal character and the advantage of the utility model.The technician of the industry should understand; The utility model is not restricted to the described embodiments; The principle of describing in the foregoing description and the instructions that the utility model just is described; Under the prerequisite that does not break away from the utility model spirit and scope, the utility model also has various changes and modifications, and these variations and improvement all fall in the utility model scope that requires protection.The utility model requires protection domain to be defined by appending claims and equivalent thereof.
Claims (5)
1. the ultrasonic ranging sensor comprises CPU module, signal processing module and transceiver ultrasonic transducer; Said CPU module comprises CPU and second source circuit; Each circuit is connected in said second source circuit and the CPU module; It is characterized in that: said CPU module also comprises schmidt trigger circuit, echoed signal output driving circuit, ultrasonic emitting driving circuit and automatic gain control Driver Circuit; The trigger pip output terminal of outside range measurement system main frame is connected with the trigger pip input end of the schmidt trigger circuit of CPU module; The output terminal of said schmidt trigger circuit is connected with the first external interrupt port of CPU; The echoed signal output terminal of CPU is connected with the echoed signal input end of outside range measurement system main frame through the echoed signal output driving circuit; The gain control signal output terminal of CPU is connected with automatic gain control circuit in being arranged on signal processing module through the automatic gain control Driver Circuit, and the ultrasonic emitting drive signal output terminal of CPU is connected with transducer booster driving circuit in being arranged on signal processing module through the ultrasonic emitting driving circuit.
2. ultrasonic ranging sensor according to claim 1; It is characterized in that: said signal processing module also comprises impedance matching and pre-amplification circuit, secondary bandpass filtering amplifying circuit, active full-wave rectifier filter circuit and wave shaping comparator circuit; The terminals of said transceiver ultrasonic transducer are connected with the input end of impedance matching and pre-amplification circuit and the output terminal of transducer booster driving circuit respectively; The output terminal of impedance matching and pre-amplification circuit is connected through the input end of said automatic gain control circuit with secondary bandpass filtering amplifying circuit; The output terminal of secondary bandpass filtering amplifying circuit is connected with the input end of active full-wave rectifier filter circuit; The output terminal of active full-wave rectifier filter circuit is connected with the input end of wave shaping comparator circuit, and the output terminal of wave shaping comparator circuit is connected with the second external interrupt port of said CPU.
3. ultrasonic ranging sensor according to claim 1 and 2; It is characterized in that: said signal processing module also is provided with emitter follower type mid-point voltage driving circuit, said emitter follower type mid-point voltage driving circuit respectively with impedance matching and pre-amplification circuit, secondary bandpass filtering amplifying circuit and active full-wave rectifier filter circuit in the in-phase input end of operational amplifier be connected.
4. ultrasonic ranging sensor according to claim 1 and 2 is characterized in that: the said automatic gain control circuit that is arranged in the signal processing module, and between said impedance matching and pre-amplification circuit and secondary bandpass filtering amplifying circuit.
5. ultrasonic ranging sensor according to claim 3; It is characterized in that: the said wave shaping comparator circuit that is arranged in the signal processing module is provided with comparer; The triggering reference voltage terminal of said comparer is connected with the positive pole of diode, and the negative pole of said diode is connected with the output terminal of said emitter follower type mid-point voltage driving circuit.
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| CN2012201084617U CN202486313U (en) | 2012-03-21 | 2012-03-21 | Ultrasonic ranging sensor |
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| CN2012201084617U CN202486313U (en) | 2012-03-21 | 2012-03-21 | Ultrasonic ranging sensor |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106526599A (en) * | 2016-11-21 | 2017-03-22 | 重庆兆洲科技发展有限公司 | Ultrasonic ranging system, echo signal receiving method and device |
| CN107765235A (en) * | 2016-08-16 | 2018-03-06 | 合肥科盛微电子科技有限公司 | The ultrasonic ranging algorithm extracted based on digital filtering, digital envelope |
| CN110703235A (en) * | 2019-10-29 | 2020-01-17 | 南京俊禄科技有限公司 | Ultrasonic measurement system and method thereof |
| CN112192561A (en) * | 2020-08-25 | 2021-01-08 | 国科微城市智能科技(南京)有限责任公司 | Action deviation rectifying system and method for robot |
-
2012
- 2012-03-21 CN CN2012201084617U patent/CN202486313U/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107765235A (en) * | 2016-08-16 | 2018-03-06 | 合肥科盛微电子科技有限公司 | The ultrasonic ranging algorithm extracted based on digital filtering, digital envelope |
| CN106526599A (en) * | 2016-11-21 | 2017-03-22 | 重庆兆洲科技发展有限公司 | Ultrasonic ranging system, echo signal receiving method and device |
| CN110703235A (en) * | 2019-10-29 | 2020-01-17 | 南京俊禄科技有限公司 | Ultrasonic measurement system and method thereof |
| CN112192561A (en) * | 2020-08-25 | 2021-01-08 | 国科微城市智能科技(南京)有限责任公司 | Action deviation rectifying system and method for robot |
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Granted publication date: 20121010 Termination date: 20150321 |
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