CN112903059A - Pavement monitoring terminal and method thereof - Google Patents
Pavement monitoring terminal and method thereof Download PDFInfo
- Publication number
- CN112903059A CN112903059A CN202110328545.5A CN202110328545A CN112903059A CN 112903059 A CN112903059 A CN 112903059A CN 202110328545 A CN202110328545 A CN 202110328545A CN 112903059 A CN112903059 A CN 112903059A
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- induction
- liquid level
- water
- touch
- cavity
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F23/00—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
- G01F23/14—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measurement of pressure
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F23/00—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
- G01F23/22—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water
- G01F23/24—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring variations of resistance of resistors due to contact with conductor fluid
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F23/00—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
- G01F23/22—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water
- G01F23/26—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring variations of capacity or inductance of capacitors or inductors arising from the presence of liquid or fluent solid material in the electric or electromagnetic fields
Abstract
The invention discloses a road surface monitoring terminal and a method thereof, wherein the terminal comprises a shell, the shell is provided with a liquid level detection cavity, the upper end of the liquid level detection cavity is opened, one side of the liquid level detection cavity is provided with an induction cavity, a circuit board is arranged in the induction cavity, the circuit board is provided with a controller, a communication unit, a touch water detection circuit and an induction comparison water detection circuit, the communication unit, the touch water detection circuit and the induction comparison water detection circuit are connected with the controller, and the controller is in communication connection with a remote monitoring platform through the communication unit; the induction comparison water detection circuit comprises a comparator and two electrodes, the two electrodes are arranged on the upper end face of the induction cavity at intervals, the comparator detects the resistance value between the two electrodes, and when the resistance value between the two electrodes is smaller than 2M impedance, the controller judges that water exists on the road surface; the touch water detection circuit comprises a touch chip, an induction gasket of the touch chip is tightly attached to the upper end face of the induction cavity, and the controller judges that water exists on the road surface when the change of the capacitance induction value of the induction gasket is greater than a threshold value; the bottom of the liquid level detection cavity is provided with a liquid level sensor for measuring the liquid level height of the liquid level detection cavity. The invention can more accurately monitor whether the road surface has water, and is convenient for obtaining accurate and real water level value.
Description
Technical Field
The invention relates to the technical field of road monitoring equipment, in particular to a road surface monitoring terminal and a method thereof.
Background
In the prior art, liquid level measurement generally adopts an absolute pressure mode and a static pressure mode to measure the liquid level, the measurement accuracy of the absolute pressure mode is relatively poor, the measurement accuracy of the static pressure mode is relatively high, and the other end of the sensor needs to be communicated with the atmosphere.
In the liquid level measurement of the road surface accumulated water, a related device needs to be buried underground, meanwhile, IP68 protection needs to be considered, and in the application of the technical scene, when the water passes through the equipment, only an absolute pressure mode sensor can be adopted to measure the liquid level. However, the measuring method has the defects that the measuring method is influenced by atmospheric pressure, the measuring precision is influenced by atmospheric pressure fluctuation, the zero drift problem of measurement exists, particularly, the influence on the surface water level meter with a low measuring liquid level range is larger, even the measurement is inaccurate, and the invention is modified and invented aiming at the problem.
Disclosure of Invention
The invention aims to provide a road surface monitoring terminal and a method thereof.
The technical scheme adopted by the invention is as follows:
a road surface monitoring terminal comprises a shell, wherein the shell is provided with a liquid level detection cavity, the upper end of the liquid level detection cavity is opened, one side of the liquid level detection cavity is provided with an induction cavity with a closed upper end surface, a circuit board is arranged in the induction cavity, a controller, a communication unit connected with the controller, a touch water detection circuit and an induction comparison water detection circuit are arranged on the circuit board, and the controller is in communication connection with a remote monitoring platform through the communication unit; the induction comparison water detection circuit comprises a comparator and two electrodes, the two electrodes are arranged on the upper end face of the induction cavity at intervals, the comparator detects the resistance value between the two electrodes, and when the resistance value between the two electrodes is smaller than 2M impedance, the controller judges that water exists on the road surface; the touch water detection circuit comprises a touch chip, the touch chip is electrically connected with an induction gasket, the induction gasket is arranged in a manner of being tightly attached to the bottom surface of the upper end surface of the induction cavity, the touch chip detects the change of an external capacitance induction value of the upper end surface of the induction cavity through the induction gasket, and the controller judges that water exists on the road surface when the change of the capacitance induction value of the induction gasket is greater than a threshold value; the bottom that the casing corresponds the liquid level detection chamber is equipped with level sensor, and level sensor electric connection controller, level sensor survey the liquid level height in liquid level detection chamber and transmit to monitoring platform via the controller when the road surface has water.
Further, as a preferred embodiment, the touch chip is a BS83B04C touch chip, and the sensing pad is connected to a touch pin of the touch chip through a conductive spring.
Further, as a preferred embodiment, the comparator is an SGM321YC5/TR operational amplifier, one electrode is connected to one input terminal of the operational amplifier through a resistor R12 with a resistance of 2M Ω, the other electrode is directly connected to the other input terminal of the operational amplifier, the output terminal of the operational amplifier is connected to the other input terminal of the operational amplifier through a resistor R6, one input terminal of the operational amplifier is grounded through a resistor R21, the other input terminal of the operational amplifier is grounded through a resistor R20, the output terminal of the operational amplifier is respectively connected to one end of a resistor R22 and one end of a capacitor C2, the other ends of the resistor R22 and the capacitor C2 are grounded, a power source VCC is respectively connected to the positive power source and one electrode of the operational amplifier, the power source VCC is grounded through a capacitor C4, the negative power source of the operational amplifier is grounded, the values of the capacitors C2 and C4 are 100nF, the values of the resistors R20 and R21, the value of the resistor R22 is 200K omega.
Further, as a preferred embodiment, the liquid level sensor uses a MAX3488EESA chip.
Further, as a preferred embodiment, the communication unit is a communication circuit based on an NB-IOT chip.
Further, as a preferred embodiment, the monitoring terminal further comprises a matched password gun, wherein the password gun comprises a microprocessor, a touch screen and an electromagnet unit, the touch screen and the electromagnet unit are connected with the microprocessor, the microprocessor acquires a user password through the touch screen and outputs a password square wave based on the user password, the electromagnet unit excites an electromagnet to generate a square wave magnetic field based on the password square wave, a controller of the monitoring terminal is connected with a hall element circuit, the hall element circuit senses the magnetic field intensity change of the electromagnet and outputs a PWM square wave with a linearly changing duty ratio as a decryption square wave, the controller acquires a decryption password based on the decryption square wave, a switch password is arranged in the controller, and the controller controls the monitoring terminal to be switched on and off based on a comparison result of the decryption password and.
A pavement monitoring terminal method comprises the following steps:
further, as a preferred embodiment, in step 1, under the condition of no water, the device automatically performs zero-setting processing on the currently read level value every certain period, so as to ensure that the reading H =0 of the true level value.
Further, as a preferred embodiment, in step 2, when the resistance value between the two electrodes of the induction comparison water detection circuit is smaller than 2M impedance, the controller determines that the road surface has water.
Further, as a preferred embodiment, in step 2, when the variation of the capacitance sensing value of the sensing pad of the touch water detection circuit is greater than the threshold, the controller determines that water is present on the road surface.
Further, as a preferred embodiment, the method further comprises a step 6 of acquiring a current atmospheric pressure value by the monitoring platform, and compensating through the atmospheric pressure to obtain an accurate real water level value for displaying.
By adopting the technical scheme, the magnetic password is received through the Hall switch to be started or shut down, the touch chip and the liquid level sensor are subjected to zero resetting initialization after the starting, and the device can automatically perform zero resetting processing on the currently read liquid level value at certain intervals under the condition of no water (judged by the touch sensor and the induction comparator), so that the reading H =0 of the true liquid level value is ensured;
when the equipment is contacted with water (judged by a touch sensor and an induction comparator), the touch part is awakened, the single chip microcomputer starts comparison induction detection, if the touch detection water and the induction comparator detect the water at the same time, the sensor is started to read the current water level value H2, the current water level value H1 is subtracted, H = H2-H1 is the current true liquid level value, and if the liquid level height reaches a set threshold value, the alarm is uploaded to a platform. Because the liquid level sensor is an absolute pressure sensor, when the liquid level sensor is submerged by water, the reading can change along with the change of atmospheric pressure (the atmospheric pressure change amount can reach 5-10CM in normal weather after 1 day), and the accurate real water level value is obtained by tracking and extracting the local atmospheric pressure change amount through the platform for compensation, and the error can be basically controlled within 1 CM.
Drawings
The invention is described in further detail below with reference to the accompanying drawings and the detailed description;
FIG. 1 is a schematic structural diagram of a pavement monitoring terminal according to the present invention;
FIG. 2 is a schematic top view of a pavement monitoring terminal according to the present invention;
FIG. 3 is a schematic bottom view of a pavement monitoring terminal according to the present invention;
FIG. 4 is a schematic diagram of a circuit of a road surface monitoring terminal according to the present invention;
FIG. 5 is a circuit diagram of a touch water detection circuit of a road surface monitoring terminal according to the present invention;
FIG. 6 is a circuit diagram of an inductive comparison water detection circuit of a road surface monitoring terminal according to the present invention;
fig. 7 is a schematic flow chart of a road surface monitoring method according to the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application.
As shown in one of fig. 1 to 6, the invention discloses a road surface monitoring terminal, which comprises a shell 1, wherein the shell 1 is provided with a liquid level detection cavity 2, the upper end of the liquid level detection cavity 2 is opened, one side of the liquid level detection cavity 2 is provided with an induction cavity 3 with a closed upper end surface, a circuit board 4 is installed in the induction cavity 3, the circuit board 4 is provided with a controller, a communication unit, a touch water detection circuit and an induction comparison water detection circuit, the communication unit, the touch water detection circuit and the induction comparison water detection circuit are connected with the controller, and the controller is in communication connection with a remote monitoring platform through the communication unit; the induction comparison water detection circuit comprises a comparator and two electrodes 5(J3, J4), wherein the two electrodes 5 are arranged on the upper end face of the induction cavity 3 at intervals, the comparator detects the resistance value between the two electrodes 5, and when the resistance value between the two electrodes 5 is smaller than 2M, the impedance controller judges that water exists on the road surface; the touch water detection circuit comprises a touch chip, the touch chip is electrically connected with a sensing gasket 6(J5), the sensing gasket 6 is arranged close to the bottom surface of the upper end surface of the sensing cavity 3, the touch chip detects the change of an external capacitance sensing value of the upper end surface of the sensing cavity 3 through the sensing gasket 6, and the controller judges that water exists on the road surface when the capacitance sensing value change quantity of the sensing gasket 6 is larger than a threshold value; the bottom that casing 1 corresponds liquid level detection chamber 2 is equipped with level sensor 7, and level sensor 7 electric connection director, level sensor 7 survey the liquid level height in liquid level detection chamber 2 and transmit to monitoring platform via the controller when the road surface has water.
Further, as a preferred embodiment, the touch chip is a touch chip of BS83B04C, and the sensing pad 6 is connected to a touch pin of the touch chip through the conductive spring 8.
Further, as shown in fig. 6, as a preferred embodiment, the comparator is an SGM321YC5/TR operational amplifier, one electrode 5 is connected to one input terminal of the operational amplifier through a resistor R12 with a resistance of 2M Ω, the other electrode 5 is directly connected to the other input terminal of the operational amplifier, the output terminal of the operational amplifier is connected to the other input terminal of the operational amplifier through a resistor R6, one input terminal of the operational amplifier is grounded through a resistor R21, the other input terminal of the operational amplifier is grounded through a resistor R20, the output terminal of the operational amplifier is respectively connected to one terminal of a resistor R22 and one terminal of a capacitor C2, the other terminals of the resistor R22 and the capacitor C2 are grounded, a power source VCC is respectively connected to the positive power source and one electrode 5 of the operational amplifier, the power source VCC is grounded through a capacitor C4, the negative power source of the operational amplifier is grounded, the values of the capacitors C2 and C58, the values of the resistors R20 and R21 are 100K Ω, and the value of the resistor R22 is 200K Ω.
Further, as a preferred embodiment, the liquid level sensor 7 is a MAX3488EESA chip.
Further, as a preferred embodiment, the communication unit is a communication circuit based on an NB-IOT chip.
Further, as a preferred embodiment, the circuit board 4 is electrically connected to a battery, which supplies power to the terminal.
Further, as a preferred embodiment, the monitoring terminal further comprises a matched password gun, wherein the password gun comprises a microprocessor, a touch screen and an electromagnet unit, the touch screen and the electromagnet unit are connected with the microprocessor, the microprocessor acquires a user password through the touch screen and outputs a password square wave based on the user password, the electromagnet unit excites an electromagnet to generate a square wave magnetic field based on the password square wave, a controller of the monitoring terminal is connected with a hall element circuit, the hall element circuit senses the magnetic field intensity change of the electromagnet and outputs a PWM square wave with a linearly changing duty ratio as a decryption square wave, the controller acquires a decryption password based on the decryption square wave, a switch password is arranged in the controller, and the controller controls the monitoring terminal to be switched on and off based on a comparison result of the decryption password and.
As shown in fig. 7, the invention also discloses a road surface monitoring terminal method, which comprises the following steps:
further, as a preferred embodiment, in step 1, under the condition of no water, the device automatically performs zero-setting processing on the currently read level value every certain period, so as to ensure that the reading H =0 of the true level value.
Further, as a preferred embodiment, in step 2, when the resistance value between the two electrodes 5 of the induction comparison water detection circuit is smaller than 2M impedance, the controller determines that the road surface has water.
Further, as a preferred embodiment, in step 2, when the capacitance sensing value variation of the sensing pad 6 of the touch water detection circuit is larger than the threshold, the controller determines that water is on the road surface.
Further, as a preferred embodiment, the method further comprises a step 6 of acquiring a current atmospheric pressure value by the monitoring platform, and compensating through the atmospheric pressure to obtain an accurate real water level value for displaying.
The platform atmospheric pressure correction method comprises the following steps: d ═ C- (B-a) × 0.102, where a ═ atmospheric pressure (in units of Pa) is preserved when the upper limit of liquid level alarms for the first time (the upper limit alarms begin to record from 0 to 1); b is the current atmospheric pressure (unit Pa) is regularly pushed by other equipment or a meteorological station; c is the current liquid level height (in mm); d is the new liquid level height (in mm).
By adopting the technical scheme, the magnetic password is received through the Hall switch to be started or shut down, the touch chip and the liquid level sensor 7 are subjected to zero resetting initialization after the starting, and the device can automatically perform zero resetting processing on the currently read liquid level value at certain intervals under the condition of no water (judged by the touch sensor and the induction comparator), so that the reading H =0 of the true liquid level value is ensured;
when the equipment is contacted with water (judged by a touch sensor and an induction comparator), the touch part is awakened, the single chip microcomputer starts comparison induction detection, if the touch detection water and the induction comparator detect the water at the same time, the sensor is started to read the current water level value H2, the current water level value H1 is subtracted, H = H2-H1 is the current true liquid level value, and if the liquid level height reaches a set threshold value, the alarm is uploaded to a platform. Because the liquid level sensor 7 is an absolute pressure sensor, when the liquid level sensor is submerged by water, the reading can change along with the change of atmospheric pressure (the atmospheric pressure change amount can reach 5-10CM in normal weather after 1 day), and the accurate real water level value is obtained by tracking and extracting the local atmospheric pressure change amount through the platform for compensation, and the error can be basically controlled within 1 CM.
It is to be understood that the embodiments described are only a few embodiments of the present application and not all embodiments. The embodiments and features of the embodiments in the present application may be combined with each other without conflict. The components of the embodiments of the present application, generally described and illustrated in the figures herein, can be arranged and designed in a wide variety of different configurations. Thus, the detailed description of the embodiments of the present application is not intended to limit the scope of the claimed application, but is merely representative of selected embodiments of the application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
Claims (10)
1. The utility model provides a road surface monitor terminal which characterized in that: the device comprises a shell, wherein the shell is provided with an induction cavity and a liquid level detection cavity, the upper end of the liquid level detection cavity is provided with an opening, an accommodating cavity is arranged on one side of the liquid level detection cavity of the liquid level cavity in an induction manner, a circuit board is arranged in the cavity induction cavity, a controller, a communication unit, a touch water detection circuit and an induction comparison water detection circuit are arranged on the circuit board, the communication unit, the touch water detection circuit and the induction comparison water detection circuit are connected with the controller, and the controller is in communication connection with a remote monitoring; the induction comparison water detection circuit comprises a comparator and two electrodes, the two electrodes are arranged on the end face of the induction cavity at intervals, the comparator detects the resistance value between the two electrodes, and when the resistance value between the two electrodes is smaller than 2M impedance, the controller judges that water exists on the road surface; the touch water detection circuit comprises a touch chip, the touch chip is electrically connected with an induction gasket, the induction gasket is tightly attached to the inner side of the end face of the induction cavity, the touch chip detects the change of an external capacitance induction value of the upper end face of the induction cavity through the induction gasket, and the controller judges that water exists on the road surface when the change of the capacitance induction value of the induction gasket is greater than a threshold value; the bottom that the casing corresponds the liquid level detection chamber is equipped with level sensor, and level sensor electric connection controller, level sensor survey the liquid level height in liquid level detection chamber and transmit to monitoring platform via the controller when the road surface has water.
2. The pavement monitoring terminal according to claim 1, characterized in that: the touch chip adopts a touch chip of BS83B04C, and the induction gasket is connected with a touch pin of the touch chip through a conductive spring.
3. The pavement monitoring terminal according to claim 1, characterized in that: the comparator adopts an SGM321YC5/TR operational amplifier, one electrode is connected with one input end of the operational amplifier through a resistor R12 with the resistance value of 2M omega, the other electrode is directly connected with the other input end of the operational amplifier, the output end of the operational amplifier is connected with the other input end of the operational amplifier through a resistor R6, one input end of the operational amplifier is grounded through a resistor R21, the other input end of the operational amplifier is grounded through a resistor R20, the output end of the operational amplifier is respectively connected with one end of a resistor R22 and one end of a capacitor C2, the other ends of the resistor R22 and a capacitor C2 are grounded, a power supply VCC is respectively connected with the positive electrode and one electrode of the operational amplifier, the power supply VCC is grounded through a capacitor C4, the negative electrode of the operational amplifier is grounded, the values of the capacitors C2 and C4 are 100nF, the values of the resistors R20 and R21 are 100K omega, and.
4. The pavement monitoring terminal according to claim 1, characterized in that: the liquid level sensor selects a MAX3488EESA chip, and the communication unit is a communication circuit based on an NB-IOT chip.
5. The pavement monitoring terminal according to claim 1, characterized in that: the monitoring terminal comprises a microprocessor, a touch screen and an electromagnet unit, the touch screen and the electromagnet unit are connected with the microprocessor, the microprocessor acquires a user password through the touch screen and outputs a password square wave based on the user password, the electromagnet unit excites an electromagnet to generate a square wave magnetic field based on the password square wave, a controller of the monitoring terminal is connected with a Hall element circuit, the Hall element circuit senses the magnetic field intensity change of the electromagnet and outputs a PWM square wave with a linearly changing duty ratio as a decryption square wave, the controller acquires a decryption password based on the decryption square wave, a switch password is arranged in the controller, and the controller controls the monitoring terminal to be switched on and off based on a comparison result of the decryption password and the built-in switch password.
6. A road surface monitoring method using the road surface monitoring terminal according to any one of claims 1 to 5, characterized in that: the method comprises the following steps:
step 1, after starting up, carrying out zero reset initialization on a touch chip and a liquid level sensor;
step 2, whether the water detection circuit detects that water exists on the road surface or not is detected through touch or induction comparison; if yes, executing step 3; otherwise, the liquid level sensor returns to zero;
step 3, judging whether the touch water detection circuit and the induction comparison water detection circuit simultaneously monitor that water exists on the road surface; if yes, executing step 4; otherwise, executing the step 2 after waiting for the set time;
step 4, starting a liquid level sensor to obtain the current water level value of the liquid level detection cavity and calculating to obtain the true value of the current liquid level;
step 5, judging whether the real value of the current liquid level is larger than a liquid level threshold value; if so, the controller uploads the acquired data to the monitoring platform through the communication unit; otherwise, step 2 is executed.
7. A pavement monitoring method according to claim 6, characterized in that: in step 1, under the condition of no water, the device automatically performs zero-resetting processing on the current reading liquid level value every certain period, so as to ensure that the reading H =0 of the real liquid level value.
8. A pavement monitoring method according to claim 6, characterized in that: and 2, when the resistance value between the two electrodes of the induction comparison water detection circuit is smaller than 2M impedance, the controller judges that water exists on the road surface.
9. A pavement monitoring method according to claim 6, characterized in that: and 2, when the capacitance sensing value variation of the sensing gasket of the touch water detection circuit is greater than a threshold value, the controller judges that water exists on the road surface.
10. A pavement monitoring method according to claim 6, characterized in that: the method further comprises a step 6 of acquiring the current atmospheric pressure value by the monitoring platform, and compensating through the atmospheric pressure to obtain an accurate real water level value for displaying.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110328545.5A CN112903059A (en) | 2021-03-26 | 2021-03-26 | Pavement monitoring terminal and method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110328545.5A CN112903059A (en) | 2021-03-26 | 2021-03-26 | Pavement monitoring terminal and method thereof |
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| Publication Number | Publication Date |
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| CN112903059A true CN112903059A (en) | 2021-06-04 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202110328545.5A Pending CN112903059A (en) | 2021-03-26 | 2021-03-26 | Pavement monitoring terminal and method thereof |
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| Country | Link |
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| CN (1) | CN112903059A (en) |
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2021
- 2021-03-26 CN CN202110328545.5A patent/CN112903059A/en active Pending
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