CN111272149A

CN111272149A - Digital sensor for intelligently measuring depth of bottom mud of river and lake

Info

Publication number: CN111272149A
Application number: CN202010075534.6A
Authority: CN
Inventors: 李国政; 徐军; 许峰; 曹安民
Original assignee: Guizhou Broadcasting & Tv Information Network Co ltd
Current assignee: Guizhou Broadcasting & Tv Information Network Co ltd
Priority date: 2020-01-22
Filing date: 2020-01-22
Publication date: 2020-06-12
Anticipated expiration: 2040-01-22
Also published as: CN111272149B

Abstract

The invention provides a river and lake bottom mud depth intelligent measurement digital sensor which adopts an inductance principle and comprises a rebound shaft, an LVDT iron core and a precision sleeve, wherein the rebound shaft runs in a precision sleeve bearing and is connected with the LVDT iron core. The rebound shaft is contacted with the bottom mud, so that the rebound shaft cuts a magnetic induction line generated by the LVDT iron core in the precise sleeve, and corresponding change of an electric signal is formed along with the magnetic induction line, and the depth of the bottom mud of the river and the lake is represented after the electric signal is subjected to analog-to-digital conversion; the intelligent digital sensor for measuring the depth of the river and lake bottom mud is convenient, rapid and accurate to measure, the service life cost can be greatly increased by adopting the sensor principle and materials, the measurement requirements of different perception scenes can be met, and the intelligent digital sensor for measuring the depth of the river and lake bottom mud is more suitable for large-scale deployment.

Description

Digital sensor for intelligently measuring depth of bottom mud of river and lake

Technical Field

The invention belongs to the technical field of measurement and sensing, and particularly relates to an intelligent digital sensor for measuring the depth of bottom mud in rivers and lakes.

Background

At present, the treatment of black and odorous rivers and water environment of urban inland rivers in China become important parts of economic transformation and civil engineering, and have extremely important practical significance on human health and sustainable development of green water in Qingshan mountains. However, the filth, microorganism, particulate matters and the like in the rivers and the lakes are deposited at the bottoms of the rivers and the lakes to form bottom mud. The sediment can be released repeatedly, which causes secondary pollution to rivers and lakes, so that the sediment quantity has great significance for water environment improvement.

Particularly, aiming at early-stage investigation of dredging, the depth of bottom mud of river and lake bottom mud needs to be clear, and the depth is used for accurately estimating the engineering quantity, deciding the engineering method and the treatment scheme, and bringing immeasurable economic value.

The sediment measuring device on the existing market is a mechanical device commonly used, a digital sensor is not arranged, the indication value of a sediment sampling pipe is required to be read manually, the sediment sampling pipe needs to be cleaned after each measurement, the operation is complicated, and the sampling and measuring efficiency of the whole river and lake is low.

Disclosure of Invention

In view of this, the invention aims to provide an intelligent digital sensor for measuring the depth of river and lake bottom mud, which can accurately detect the depth of the river and lake bottom mud.

A digital sensor for intelligently measuring the depth of bottom mud of rivers and lakes comprises a detecting head (1), a rebound shaft (2), an iron core (3), a sleeve pipe (4), a coil (5) and a signal processing module;

the front end of the rebound shaft (2) is fixedly connected with the probe (1), and the rear end of the rebound shaft is fixedly connected with the iron core (3); the iron core (3) is arranged in the sleeve pipe (4) through a bearing and moves in the sleeve pipe along the axial direction; the coil (5) is arranged outside the sleeve pipe (4); pulse signals are introduced into the coil (5) to be used as excitation signals;

the signal processing module: receiving the electromotive force of the coil (5) in real time, and recording the electromotive force at the moment as E1 when the potential change rate starts to change from keeping unchanged to beginning; when the electromotive force change rate is larger than a set threshold value, recording the electromotive force at this time as E2; the river mud depth Δ l is calculated as:

wherein B represents the magnetic induction intensity of the coil (5), and v represents the moving speed of the sensor.

Preferably, the pulse width p and the time delay T of the excitation signal satisfy p-2 (T-T), and T is the period of the pulse signal.

Preferably, the sleeve tube (4) is made of copper.

The invention has the following beneficial effects:

the invention provides a river and lake bottom mud depth intelligent measurement digital sensor which adopts an inductance principle and comprises a rebound shaft, an LVDT iron core and a precision sleeve, wherein the rebound shaft runs in a precision sleeve bearing and is connected with the LVDT iron core. The rebound shaft is in contact with the bottom mud, so that the rebound shaft cuts a magnetic induction line generated by the LVDT iron core in the precise sleeve, corresponding change of an electric signal is formed, and the depth of the bottom mud of the river or lake is represented after the electric signal is subjected to analog-to-digital conversion. The overall structure includes copper resilience axle, casing and assorted installed part. The intelligent digital sensor for measuring the depth of the river and lake bottom mud is convenient, rapid and accurate to measure, the service life cost can be greatly increased by adopting the sensor principle and materials, the measurement requirements of different perception scenes can be met, and the intelligent digital sensor for measuring the depth of the river and lake bottom mud is more suitable for large-scale deployment.

Drawings

FIG. 1 is a structure diagram of a digital sensor for intelligently measuring the depth of bottom mud in rivers and lakes;

labeled as: 1-a probe head; 2-a rebound shaft; 3-an iron core; 4-a sleeve tube; 5-a coil;

FIG. 2 is a diagram of internal components of a digital sensor for intelligently measuring the depth of bottom mud in a river or lake;

FIG. 3 is a view of a usage scenario of the intelligent measurement digital sensor for the depth of the bottom mud of the river or lake;

Detailed Description

The invention is described in detail below by way of example with reference to the accompanying drawings.

The invention discloses a river and lake sediment depth intelligent measurement digital sensor, which comprises a detection head 1, a rebound shaft 2, an iron core 3, a sleeve pipe 4, a coil 5 and a signal processing module, wherein the detection head is connected with the rebound shaft 2; the rebound shaft 2 is fixedly connected with the detecting head 1 and the rear end is fixedly connected with the iron core 3; the iron core 3 is arranged in a sleeve pipe 4 made of copper through a bearing and moves along the axial direction in the sleeve pipe; the coil 5 is arranged outside the sleeve tube 4; the coil 5 is fed with a pulse signal as an excitation signal, the pulse width p and the delay T of the pulse signal should satisfy that p is 2(T-T), and T is the period of the pulse signal. In the embodiment, the pulse signal period T is set to be 20us, the pulse width p is controlled to be 30us, and the delay T is 5 us.

When the rebound shaft 2 generates displacement change, the iron core 3 is driven to act, and when the iron core 3 moves in the sleeve pipe 4, induced electromotive force generated by the cutting coil 5 is generated; by measuring the magnitude of the induced electromotive force, the signal processing module is used for receiving a voltage signal generated by the coil 5 and calculating the river bottom mud according to externally input data.

As shown in fig. 3, fig. 3 is an embodiment of binding a sensor at the front end of a depth detection stick at a river, lake or ship or a bridge, vertically lowering the digital sensor for intelligently measuring the depth of bottom mud of the river or lake and the depth detection stick, and receiving a voltage signal by a signal processing module, wherein the specific working process is as follows:

the river and lake bottom mud depth intelligent measurement digital sensor vertically touches the bottom of the water through the vertical rod, and the rebound shaft can generate displacement under the resistance action of the water after the water enters the river and lake bottom mud depth intelligent measurement digital sensor, and the displacement is set as x; the rebound shaft drives the iron core to move to cut the magnetic induction lines, so that corresponding change E ═ B x v of the electric potential E is formed therewith. Wherein B represents magnetic induction and v represents sensor speed;

because the damping coefficient of water cannot change along with the change of water depth, the retraction speed of the rebound shaft is uniform, namely the potential also changes at a uniform speed, namely the potential change rate along with time is not changed; when the sensor contacts river mud, the damping coefficients of the river mud and lake water are different, and the damping coefficients are increased along with the increase of the depth of the river mud, so that the retraction speed of the rebound shaft cannot be kept constant and is supposed to be faster and faster, and the potential change rate obtained by the sensor cannot be kept constant, so that whether the lower end of the sensor contacts the river mud or not can be judged according to the potential change rate; the potential change rate begins to be kept unchanged, and when the potential change rate begins to change, the lower end of the sensor begins to contact river mud, and the electromotive force at the moment is recorded as E1;

the sensor continuously moves downwards in river mud, meanwhile, the rebound shaft also gradually retracts, when the rebound shaft touches a river bed, a damping coefficient is suddenly increased, the retraction rate of the rebound shaft also changes suddenly, and the electromotive force change rate also changes correspondingly, according to a plurality of test results, a potential change rate threshold is determined, when the electromotive force change rate is larger than a set threshold, the fact that the lower end of the rebound shaft touches the river bed at the moment is indicated, and the electromotive force at the moment is recorded as E2; then, when the sensor starts to touch the river mud to reach the river bed, assuming that the sensor is displaced in the river mud by Δ l (i.e. the sediment depth) and the potential change detected by the sensor is E2-E1, the river mud depth can be obtained according to the formula: E2-E1 ═ B Δ lv.

The excitation signal is a pulse signal, and the pulse width p and the time delay T of the pulse signal are required to satisfy that p is 2(T-T), and T is the period of the pulse signal. In the embodiment, the pulse signal period T is set to be 20us, the pulse width p is controlled to be 30us, and the delay T is 5 us.

During sensing measurement, the change of an electric signal generated by collecting an excitation signal is controlled to output a 0-5V voltage signal through signal amplification and signal adjustment, the voltage signal is simultaneously output to a 24-bit AD acquisition circuit and converted into a digital signal, the digital signal is input into an MCU, and a standard digital sensor is formed through the MCU and an RS485 modulation circuit.

In summary, the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The digital sensor for intelligently measuring the depth of bottom mud in rivers and lakes is characterized by comprising a detecting head (1), a rebound shaft (2), an iron core (3), a sleeve pipe (4), a coil (5) and a signal processing module;

the signal processing module: receiving the electromotive force of the coil (5) in real time, and recording when the potential change rate starts to change from constant toThe electromotive force at this time was E1; when the electromotive force change rate is larger than a set threshold value, recording the electromotive force at this time as E2; the river mud depth Δ l is calculated as:

2. The digital sensor for intelligently measuring the depth of the river and lake sediment as claimed in claim 1, wherein the pulse width p and the time delay T of the excitation signal satisfy p-2 (T-T), and T is the period of the pulse signal.

3. The digital sensor for intelligently measuring the depth of the bottom mud of the river or lake as claimed in claim 1, wherein the sleeve pipe (4) is made of copper.