CN107680359B - An integrated IoT smart manhole cover - Google Patents

Abstract

The invention discloses an integrated IoT smart manhole cover, which comprises a manhole cover body and a functional circuit system installed on the manhole cover body; the functional circuit system includes a manhole cover position sensor, a controller, a LoRa module and a power supply module; the controller adopts Bluetooth The system-on-chip BLE SoC includes a Bluetooth wireless transceiver interface and a UART interface. The Bluetooth wireless transceiver interface is connected to a Bluetooth antenna, the UART interface is connected to the LoRa module, and the LoRa module is provided with a wireless transceiver antenna; the power module is a manhole cover position sensor, controller and LoRa module to provide working power; the manhole cover body is provided with an antenna installation window, the upper part of the antenna installation window is provided with a plurality of reinforcing ribs with both ends fixed in the manhole cover body, and a glass fiber reinforced plastic baffle is arranged under the reinforcing ribs, and the LoRa module The wireless transceiver antenna is fixed under the glass fiber reinforced plastic baffle, and is located between the vertical projections of two adjacent reinforcing ribs. The invention utilizes the LoRa Internet of Things technology to realize the Internet of Things networking and real-time monitoring of the manhole cover, and has the advantages of low power consumption, low cost and excellent real-time performance.

Description

An integrated IoT smart manhole cover

technical field

The invention relates to the technical field of manhole covers in municipal public facilities, in particular to an integrated IoT intelligent manhole cover.

Background technique

At present, with the acceleration of the urbanization process, the construction of municipal public facilities has developed rapidly, and the number of underground pipes to manhole covers in urban water supply, drainage, gas, heat, real estate, electricity, telecommunications, radio and television and other departments is huge and widely distributed. Due to the lack of effective real-time monitoring and management methods, crimes such as prying open manhole covers, stealing cables or stealing manhole covers, damage, and rainwater washing away manhole covers often occur, which not only affects the normal operation of related lines or pipelines, but also causes huge direct Or indirect economic losses, and the loss of the wellhead of the manhole cover will also cause great harm to vehicles and pedestrians on the road, resulting in injury or death. Therefore, it is of great practical significance to implement digital and intelligent management of manhole covers, realize effective supervision of public facilities resources, and ensure social stability and people's personal safety.

The existing manhole cover monitoring is generally realized by adding a manhole cover monitoring device, mainly by monitoring the movement or tilting state of the manhole cover, judging whether the manhole cover is stolen or washed away, and then directly alarms on-site through sound/light warning, or through the corresponding wireless The communication network generates an alarm to the remote control center monitoring system, and the specific implementation methods are different, resulting in large differences in the manufacturing cost, operation and maintenance cost and engineering practicality of the device. In addition, due to the wide distribution of manhole covers, most of the rainwater and sewage manhole covers have no mains supply line, so the power supply mode and communication method of the manhole cover monitoring device need to be considered; The effective real-time judgment of the moving state of the manhole cover needs to be considered in the design of the manhole cover.

At present, smart manhole covers mainly have the following shortcomings:

1) The cost of the device is high and it is not suitable for large-scale applications

The existing smart manhole covers partly use ultrasonic sensors, tilt sensors, and pressure sensors to detect the movement of the manhole cover. In the normal state, it is necessary to maintain power supply to the sensor, and the cost of the sensor and the corresponding detection circuit is relatively high. In addition, ultrasonic sensors, tilt sensors or disconnection detection sensing circuits are prone to misjudgment and alarm when the vehicle is rolling over the manhole cover, which affects the anti-theft application;

2) The power consumption of the device is high, and the performance is not practical

The main purpose of manhole cover monitoring is to detect the presence or absence of the manhole cover (whether it is stolen or washed away). Some smart manhole covers have added the function of water level monitoring, and the function of closing and opening the manhole cover remotely. However, the practical value is not large, and the power consumption of the device will increase, which will also increase the trouble for the field personnel to open the manhole cover. In addition, in order to save power consumption, some manhole covers do not work in normal state, and only work when an abnormality (stolen or washed away) occurs. The monitoring system cannot know the daily state of the device, and cannot judge whether the device itself has failed;

3) Using GPRS communication, the operation and maintenance cost is high

The existing intelligent manhole covers and monitoring systems mostly use GPRS communication or Beidou communication, which requires payment. When the number of manhole covers is large, the daily operation cost is a big burden to the management department; in addition, GPRS communication or Beidou communication The high power consumption of the communication module will inevitably lead to the need to configure a large-capacity power supply or use mains power, which further increases the system cost and construction and installation cost;

4) Insufficient IoT functions

Intelligent manhole cover monitoring is an integral part of a smart city. For some important monitoring locations, the manhole cover management department will arrange special personnel to conduct inspections. The intelligent manhole cover should be able to provide a convenient way of interconnecting with the inspection personnel, that is, the connection between people and things; On the one hand, citizens, as users of municipal facilities, should provide a convenient way for citizens to inquire about manhole cover information (such as installation information and maintenance management information), so as to facilitate users to accurately provide repair report information to the management agency when they find that the manhole cover is damaged, so as to improve citizens' understanding of manhole covers. Municipal management participation;

5) Insufficient functional expansion

Smart manhole covers are mainly considered from the perspective of safety, focusing on monitoring the presence or absence of manhole covers; in addition, for some specific measurement points, such as the concentration of biogas in the pipelines in densely populated areas, it is easy to cause explosion threats, and biogas monitoring is required; important rainwater pipelines , some measuring points need to monitor the water level; or due to environmental supervision considerations, some measuring points need to monitor water quality, etc.; therefore, in addition to the comprehensive monitoring of the manhole cover, the smart manhole cover should also be easily extended to connect to other smart transmitters. To make full use of existing facilities and resources to build a smart city.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide an integrated IoT intelligent manhole cover, which utilizes the IoT technology to realize real-time monitoring of the manhole cover, with low power consumption, low cost and excellent real-time performance.

The technical scheme adopted by the present invention is: an integrated IoT intelligent manhole cover, comprising a manhole cover body and a functional circuit system installed on the manhole cover body;

The functional circuit system includes a manhole cover position sensor, a controller, a LoRa module and a power module;

The controller adopts a Bluetooth system-on-chip BLE SoC, which includes a Bluetooth wireless transceiver interface and a UART interface. The Bluetooth wireless transceiver interface is connected to a Bluetooth antenna, and the UART interface is connected to the LoRa module. The LoRa module is provided with a wireless transceiver antenna. The power module is the position of the manhole cover. Sensors, controllers and LoRa modules provide working power;

The manhole cover body is provided with an antenna installation window, the upper part of the antenna installation window is provided with a plurality of reinforcing ribs whose ends are fixed in the manhole cover body, and a light-transmitting baffle is arranged below the reinforcing ribs, and the wireless transceiver antenna of the LoRa module is fixed on the Below the light-transmitting baffle, and between the vertical projections of two adjacent reinforcing ribs.

When the present invention is applied, the bluetooth wireless communication between the manhole cover and the external mobile terminals such as mobile phones and tablet computers can be realized through the bluetooth antenna, which is convenient for real-time monitoring and early warning of the manhole cover. The LoRa module can realize low-power IoT networking between multiple manhole covers.

Further, the present invention further includes an RS485 interface circuit module, the controller further includes a second UART interface, and the controller is connected to the RS485 interface circuit module through the second UART interface, and then connected to an external function expansion module. It can make the present invention have rich functions and strong expansibility.

Preferably, the wireless transceiver antenna on the LoRa module of the present invention is a rod antenna, the reinforcing ribs on the antenna installation window are arranged on the same plane and parallel to each other, and the distance between adjacent reinforcing ribs is slightly larger than the width of the rod antenna. The use of the rod antenna 4 instead of the PCB antenna is to enhance the signal strength of signal transmission and reception, and to maintain a long distance for wireless communication, thereby facilitating the installation and deployment of the smart manhole cover.

Preferably, the reinforcing ribs on the antenna installation window are steel bars, and the light-transmitting baffle is made of light-transmitting glass fiber reinforced plastic. The strength of the manhole cover body can be not damaged while ensuring the transceiver performance of the antenna.

Further, the power module includes a solar panel, a rechargeable battery and a charging management circuit unit; the solar panel is installed under the light-transmitting baffle of the antenna installation window; the charging management circuit unit controls the charging of the solar panel to the rechargeable battery, and can Power output for rechargeable batteries. Preferably, the rechargeable battery is a single-cell rechargeable 18650 lithium battery. Charge management of rechargeable batteries is state of the art.

Preferably, the rechargeable battery and the charging management circuit unit in the controller, the LoRa module and the power module are integrated in a sealed box and installed under the manhole cover body. The pins in the controller, LoRa module and power module are led out through waterproof connectors, which can protect the functional circuit part from water, sludge, etc. Even if the manhole cover is soaked in water, the entire circuit device can still work.

Preferably, the manhole cover position sensor includes travel switches respectively installed at the edge of the manhole cover, the travel switch includes a driving ball that can abut between the edge of the manhole cover and the side wall of the wellhead, and the change of the pressure state of the driving ball can drive the travel switch. When the state of the contact changes, the signal output end of the travel switch is connected to the controller. Preferably, the controller further includes a wake-up pin, and the signal output end of the travel switch is connected to the wake-up pin. When the manhole cover leaves the manhole, the travel switch is closed, the wake-up pin 101 of the system-on-chip 1 detects the interrupt signal, and immediately enters the working state from the wake-up state, thus ensuring the real-time monitoring.

Preferably, the manhole cover is provided with an opening hole, and the included angle between the line connecting the travel switch to the center of the manhole cover and the line connecting the opening hole and the center of the manhole cover is between 8° and 15°. When someone uses the opening hole to open the manhole cover, the design of the angle range of the present invention can enable the travel switch to sense the displacement of the manhole cover more sensitively and quickly.

Further, the manhole cover position sensor also includes a reflective photoelectric switch installed at the edge of the well cover, and the connection line between the reflective photoelectric switch and the travel switch passes through the center of the manhole cover; the reflective photoelectric switch senses the reflective photoelectric switch by utilizing the reflection effect of the edge of the wellhead The distance information from the edge of the wellhead is transmitted to the controller. Preferably, at the edge of the well cover, a light-transmitting baffle is further provided between the reflective photoelectric switch and the edge of the wellhead. The partition can be made of light-transmitting glass fiber reinforced plastic, which does not affect the transmission of reflected light, and can protect the reflective photoelectric switch from the influence of external sludge and rainwater.

beneficial effect

Compared with the prior art, the present invention has the following advantages and advancements:

1. The present invention comprehensively utilizes LoRa technology, BLE technology and photoelectric sensing technology. The overall design has few components and high integration, and uses low-power devices with low device prices. On the one hand, it ensures the overall construction of the system. Low cost, suitable for large-scale promotion and application; on the other hand, the daily power consumption of the entire device can be controlled within 20uA, and a single 18650 rechargeable lithium battery can be used to power the device, without the need for commercial power or large-capacity batteries, which promotes well cover In addition, the design of the RS485 interface circuit is easy to connect to other intelligent transmitters or integrate itself into other data acquisition stations, which can realize the monitoring of various physical quantities of the manhole pipeline, and the expandable functions Many, strong integration;

2. The present invention adopts the scheme of jointly monitoring the presence or movement of the manhole cover through the travel switch and the reflective photoelectric switch. The advantages are: in terms of price, compared with other schemes such as ultrasonic sensors, tilt sensors, etc. The price of the photoelectric switch is low, the function is simple and reliable, and the environmental requirements are low. In terms of functions, on the one hand, it can ensure the real-time and accuracy of the missing manhole cover or mobile monitoring, reduce false alarms and improve practicability; power consumption;

3. The present invention uses LoRa technology to build a remote manhole cover monitoring network. Compared with the commonly used GPRS or Beidou communication methods, LoRa has low power consumption and works in free frequency bands; More than 10 kilometers, so it is the preferred way for battery-powered low-power IoT applications. In addition, the use of BLE to build on-site communication methods conforms to the current mainstream short-range communication methods of mobile terminals such as smartphones or tablet computers, which provides great convenience for managers and the public to communicate with manhole covers and facilitates inspections. or maintenance and other daily operation management;

4. The present invention adopts an integrated structure design, the component composition is simple, and the overall cost can be controlled within 200 yuan. Through the application of steel bar array and light-transmitting FRP, on the one hand, the wireless communication of rod antenna can be realized. Compared with PCB antenna, the wireless communication distance is far, which has practical value, and can also take into account the auxiliary application of solar panels; Compared with the design of encapsulating the circuit in the groove in the middle of the manhole cover that is in direct contact with the ground, the structural design of the present invention ensures the strength of the manhole cover, avoids the damage of the manhole cover caused by the rolling of vehicles, and also avoids the direct transmission of the rolling force to the circuit device. part, affecting the service life of the product.

Description of drawings

Fig. 1 shows the schematic block diagram of the functional components of the present invention;

Fig. 2 shows the schematic diagram of the application system of the present invention;

FIG. 3 is a schematic diagram showing the structure of the manhole cover of the present invention.

Detailed ways

The following is further described in conjunction with the accompanying drawings and specific embodiments.

1 to 3, the integrated IoT smart manhole cover of the present invention includes a manhole cover body 01 and a functional circuit system installed on the manhole cover body 1;

The functional circuit system includes a manhole cover position sensor, a controller 1, a LoRa module 3 and a power supply module;

The controller 1 adopts a Bluetooth system-on-chip BLE SoC, which includes a Bluetooth wireless transceiver interface 104 and a UART interface 106, wherein the Bluetooth wireless transceiver interface 104 is connected with a Bluetooth antenna 2, and the UART interface 106 is connected to the LoRa module 3, and the LoRa module 3 is provided with a wireless Transceiver antenna 4; the power module provides working power for the manhole cover position sensor, controller 1 and LoRa module 3;

The manhole cover body 01 is provided with an antenna installation window, the upper part of the antenna installation window is provided with a plurality of reinforcing ribs 04 with both ends fixed in the manhole cover body 01, and a light-transmitting baffle 05 is arranged below the reinforcing ribs 04, and the LoRa module 3 The wireless transceiver antenna 4 is fixed under the light-transmitting baffle 05 and located between the vertical projections of two adjacent reinforcing ribs 04 .

Referring to FIG. 2 , when the present invention is applied, the bluetooth wireless communication between the manhole cover and external mobile terminals such as mobile phones and tablet computers can be realized through the bluetooth antenna 2, which is convenient for real-time monitoring and early warning of the manhole cover. The LoRa module can realize low-power IoT networking between multiple manhole covers.

Example 1

The present invention also includes an RS485 interface circuit module 7, and the controller 1 further includes a second UART interface 102. The controller 1 is connected to the RS485 interface circuit module 7 through the second UART interface 102, and then connected to an external function expansion module. It can make the present invention have rich functions and strong expansibility.

The Bluetooth antenna 2 of the present invention adopts a Bluetooth PCB antenna, the wireless transceiver antenna 4 on the LoRa module 3 is a rod antenna, the reinforcing ribs 04 on the antenna installation window are arranged in parallel to each other on the same plane, and the distance between the adjacent reinforcing ribs 04 is slightly greater than The width of the rod antenna 4 . The use of the rod antenna 4 instead of the PCB antenna is to enhance the signal strength of signal transmission and reception, and to maintain a long distance for wireless communication, thereby facilitating the installation and deployment of the smart manhole cover.

The reinforcing ribs 04 on the antenna installation window are steel bars, and the light-transmitting baffle 05 is made of light-transmitting glass fiber reinforced plastic. The strength of the manhole cover body can be not damaged while ensuring the transceiver performance of the antenna.

1 and 3, the power module includes a solar panel 10, a rechargeable battery 8 and a charge management circuit unit 9; the solar panel 10 is installed under the glass fiber reinforced plastic baffle 05 of the antenna installation window; the charge management circuit unit 9 controls the solar panel Charging of rechargeable batteries, and power output of rechargeable batteries. The rechargeable battery adopts a single-cell rechargeable 18650 lithium battery. Charge management of rechargeable batteries is state of the art.

Referring to FIG. 3 , the rechargeable battery and charging management circuit unit in the controller 1 , the LoRa module 3 and the power module are integrated on a circuit board 08 and placed in the sealing box 6 , and installed under the manhole cover body 01 . The pins in the controller, LoRa module and power module are led out through the waterproof connector 07, which can protect the functional circuit part from the influence of water, sludge, etc. Even if the manhole cover is soaked in water, the entire circuit device can still work .

The manhole cover position sensor includes travel switches 5 respectively installed at the edge of the manhole cover. The travel switch 5 includes a drive ball that can abut between the edge of the manhole cover and the sidewall of the wellhead. The change of the pressure state of the drive ball can drive the contact point of the travel switch. When the state changes, the signal output end of the travel switch is connected to the controller. The controller also includes a wake-up pin 101, and the signal output end of the travel switch is connected to the wake-up pin. When the manhole cover leaves the manhole, the travel switch is closed, the wake-up pin 101 of the system-on-chip 1 detects the interrupt signal, and immediately enters the working state from the wake-up state, thus ensuring the real-time monitoring.

The manhole cover is provided with an opening hole 03, and the included angle between the line connecting the travel switch 5 to the center of the manhole cover and the line connecting the opening hole 03 to the center of the manhole cover is between 8° and 15°. When someone uses the opening hole to open the manhole cover, the design of the angle range of the present invention can enable the travel switch to sense the displacement of the manhole cover more sensitively and quickly.

The manhole cover position sensor also includes a reflective photoelectric switch 6 installed at the edge of the manhole cover. The connection between the reflective photoelectric switch 6 and the travel switch 5 passes through the center of the manhole cover; The distance information from the edge of the wellhead is transmitted to the controller. At the edge of the well cover, a light-transmitting baffle 14 is also provided between the reflective photoelectric switch and the edge of the wellhead. The partition can be made of light-transmitting glass fiber reinforced plastic, which does not affect the transmission of reflected light, and can protect the reflective photoelectric switch from the influence of external sludge and rainwater.

Example 2

Referring to Figure 1, the present invention selects a low-power bluetooth system-on-chip BLE SoC. The system-on-chip 1 is used as an integrated circuit chip and is used as the main control CPU of the intelligent manhole cover circuit. And interface resources are rich, integrated with wake-up pin 101, general UART interface 102, voltage AD conversion pin 103, Bluetooth wireless transceiver circuit 104, and general UART interface 106 and so on.

The Bluetooth wireless transceiver circuit 103 and the Bluetooth PCB antenna 2 in the system-on-chip 1 realize the Bluetooth wireless communication between the device and external mobile terminals such as mobile phones and tablet computers; the system-on-chip 1 and the LoRa module realize the low-power consumption IoT group of the present invention The purpose of using the rod antenna 4 instead of the PCB antenna is to enhance the signal strength of signal transmission and reception, so that the wireless communication can maintain a long distance, which is conducive to the installation and deployment of the smart manhole cover.

In terms of detecting the presence or absence or movement of the manhole cover, in order to ensure the real-time and accuracy of monitoring, and to ensure the low power consumption application of the device, the present invention adopts a travel switch light 5 and a reflective photoelectric switch 6 . Among them, the travel switch 5 is mechanical, has no power consumption, is installed on the edge of the manhole cover body, and is usually in a closed state, and its on-off state signal is connected to the wake-up interrupt pin of the system-on-chip 1; the reflective photoelectric switch 6 is an integrated It is composed of infrared light-emitting diodes and NPN silicon phototransistors, which are small in size and cheap in price. The device has low requirements on the reflective surface, and non-transparent materials such as iron and cement can be used as the reflective surface. The reflective photoelectric switch 6 is installed on the edge of the manhole cover body, and is distributed at 180° relative to the travel switch 5, with the edge of the manhole as the reflective surface.

Under normal conditions, the system on chip 1 is in a dormant state, and the overall power consumption of the system is within 10uA; once the manhole cover is removed from the manhole, the travel switch is closed, and the wake-up pin 101 of the system-on-chip 1 detects an interrupt signal, and immediately enters the working state from the wake-up state. To ensure real-time monitoring; at the same time, in order to prevent possible misjudgments caused by vehicle rolling or vibration, and to ensure the accuracy of monitoring, after the system-on-chip 1 enters the working state, it immediately supplies power to the photoelectric reflective switch 6 through the controlled power supply, and Measure the current signal output by the photoelectric reflection switch 6 through the voltage AD conversion pin 103; if the measurement result is less than the set threshold, it means that there is no emission surface or the reflection surface is far away, indicating that the edge of the manhole cover opposite to the installation position of the travel switch is also detached After checking the manhole, it is confirmed that the manhole cover is detached and may be stolen or washed away; after confirmation, the system-on-chip 1 immediately sends the status, time and alarm information to the monitoring center system through the LoRa module 3.

In the aspect of networking of the Internet of Things, the present invention adopts the low-power bluetooth technology BLE to realize the short-distance connection with the terminal equipment (mobile phone or PAD) held by the personnel, and adopts the LoRa wireless technology to realize the interconnection network with the monitoring center. Among them, LoRa is one of the Low Power Wide Area Network (LPWAN) communication technologies, and is an ultra-long-distance wireless transmission scheme based on spread spectrum technology adopted and promoted by Semtech in the United States. This solution changes the previous compromise between transmission distance and power consumption, and can provide users with a simple sensor network and system that can achieve long distance, long battery life, and large capacity. LoRa technology has the characteristics of long distance, low power consumption (long battery life), multi-node, low cost, and supports ranging and positioning, making LoRa technology very suitable for applications requiring low power consumption, long distance, a large number of connections, and positioning tracking. IoT applications. Compared with ZigBee/WIFI in local area network, it has the advantage of long communication distance; compared with GPRS/4G in mobile wide area network, it has the advantages of low power consumption and no need to pay for use. At present, LoRa technology and Narrowband Internet of Things technology (NB-IoT) are the two most promising low-power wide area network communication technologies, but NB_IoT relies on the network construction of mobile communication operators and has not yet been fully commercialized. Therefore, the present invention applies the LoRa technology to the monitoring of the intelligent manhole cover, which is technically advanced.

In terms of the functional scalability of the device, the present invention mainly monitors the presence or absence of the manhole cover, and then uses the UART interface 102 of the system-on-chip 1 to connect with the external RS485 interface circuit 7, and the RS485 communication bus is reserved to connect with the externally expanded intelligent transmitter or other data acquisition systems. For example, if the manhole cover of some manholes needs to monitor the water level or monitor the biogas content, the corresponding water level sensor or biogas sensor together with the corresponding measurement circuit can be packaged into a smart transmitter with an RS485 communication interface, and the smart manhole cover can communicate with the smart transmitter. Obtain the corresponding measurement information and report it to the monitoring center together. On the other hand, the smart manhole cover can also send its own status information to other data acquisition systems such as the corresponding water level observation station through the RS485 bus. Way.

In terms of the power supply design of the device, through the above-mentioned device selection and overall design, the device consists of fewer chips, and the overall power consumption is low. The device is in a dormant state most of the time, and can report the current state of the manhole cover to the monitoring center several times a day according to the set frequency, so that the management party can confirm that the device is in good operating condition. At the same time, it also supports the monitoring center to call and wake up the device; When the manhole cover is missing, under the action of the external interrupt wake-up pin, the device wakes up, starts acquisition and communication, and maintains high-frequency measurement communication to ensure that the alarm information is sent to the monitoring center, and the lost manhole cover can be located through LoRa positioning. According to the overall design, the power consumption of the device in the sleep state is within 20uA. Therefore, a single-cell rechargeable 18650 lithium battery 8 (capacity is generally about 2000mAH) can be used as the main power supply of the system, and the device can be guaranteed to work for 3 years; In order to further realize the maintenance-free power supply of the device, a small solar panel 10 and a rechargeable management circuit 9 are designed. When the manhole cover is integrated in the design, light-transmitting glass fiber reinforced plastic is reserved, which is convenient for use in places with better lighting conditions. It should be noted that due to the harsh environment of the manhole cover, dust, sludge, etc. will affect the effect of the solar panel receiving sunlight. Here, the solar power supply is only used as auxiliary charging.

In the specific application process of the present invention, the schematic diagram of the intelligent manhole cover Internet of Things application system is shown in FIG. 2 . The IoT application system of the present invention mainly includes a smart manhole cover 01, a LoRa gateway 12, a cloud server 13, various types of servers 14, a smart phone 15, a tablet 16, and related personnel 17, and the like. In the comprehensive application process, the smart manhole cover 01 of the present invention is used as a data monitoring terminal to form the LoRa local Internet of Things through the LoRa gateway 12; the LoRa gateway 12 reports data to the cloud server 13 through its own mobile communication network such as Ethernet or 4G ; Various types of servers 14 include application servers, data centers, and WEB servers that form the monitoring center, which can all perform data communication, data computing, and other specific functional operations with the cloud server. Relevant personnel 17 include manhole cover managers and the general public. They can use mobile terminals (smartphone 5 or tablet 16 ) installed with corresponding APP applications, and can also exchange data with cloud servers through mobile communication networks, query information or receive cloud server pushes various information.

In addition, at the application site of the manhole cover, relevant personnel 17 (inspectors or the public), such as pipeline inspection personnel, can use mobile terminals to inspect the status of the smart manhole cover and the collected data through the low-power Bluetooth communication BLE. Read; or, if the public finds that the manhole cover is abnormal (for example, although there is, but it is seriously damaged), it can connect with the smart manhole cover through the corresponding APP application, query the manufacturing information and operation and maintenance management information of the manhole cover, and click the APP in the APP. Click to report the abnormal situation, which is convenient for the management agency to replace the manhole cover in time, and further reduces the risk of problems with the manhole cover. Through the application of LoRa technology and BLE technology, the invention optimizes and improves the Internet of Things function of the manhole cover, and the information interaction between people and the manhole cover is more convenient.

The invention not only optimizes and innovates the circuit and function design, and realizes the low cost and high performance of the device, but also carries out the corresponding integrated design in the structure, which ensures the cost controllability, quality reliability and convenient installation of the device. performance and engineering practicability.

As shown in Figure 3, the integrated intelligent manhole cover is mainly composed of manhole cover body 01, manhole cover hinge 02, opening hole 03, travel switch 5, waterproof connector 07, sealing box 06, single 18650 lithium battery 8, circuit board 08, steel bar array 05. Translucent FRP 05, rubber rod antenna 4, solar panel 10, reflective photoelectric switch component 6 and translucent FRP 09. The manhole cover body 01, the manhole cover hinge 02 and the opening hole 03 are the standard components of the manhole cover, and the present invention is mainly for the design of other components.

Specifically, in order to solve the key problem that the antenna is shielded by the cast iron manhole cover, the present invention adopts the area of the steel bar array 05 arranged in parallel (the spacing between the steel bars is slightly wider than that of the rod antenna), so that the rod antenna 4 can pass through the gap between the two steel bars. , Receive external LoRa signals, maximize the wireless communication distance, and ensure that the strength of the manhole cover is not affected, avoid damage to the manhole cover caused by vehicle rolling, and ensure product quality; The bottom of 05 is followed by rod antenna 4 and solar panel 10; through this design, the outside of the manhole cover facing the ground is isolated from the internal rod antenna 4 and solar panel 10, so as to avoid affecting dust, sewage, etc. directly with rod antenna 4 and solar panel. 10 contact will affect the service life of the product; the light-transmitting FRP 10 can transmit electromagnetic waves and light, so that the rod antenna 4 and the solar panel 10 can work normally as designed.

As shown in Figure 3, in terms of real-time monitoring of the movement or absence of the manhole cover, the travel switch 5 and the reflective photoelectric switch 6 are both installed on the edge of the manhole cover body, distributed at 180°, and distributed at an angle of about 10° with the opening hole 3 . The travel switch 5 is in contact with the edge of the manhole through the sphere at the top, and is usually in a pressurized state; in normal times, even if the vehicle is rolled, it is generally the vibration of the up and down direction of the manhole cover, and the side vibration is small, so as to avoid the wrong status of the travel switch when the vehicle is rolled. Judgment; the reflective photoelectric switch relies on the reflection of light from the edge of the manhole to measure the distance from the switch to the edge of the manhole. By taking the above measures, once

Someone opens the manhole cover through the opening hole 03, the pressure of the travel switch 5 disappears, returns to a free state, and immediately gives a changing electrical signal, through the interrupt pin, wakes up the dormant main control circuit and starts to work. The light-transmitting glass fiber reinforced plastic 09 is installed in front of the reflective photoelectric switch 6, which does not affect the reflection effect of the edge of the manhole, and the reflective photoelectric switch 6 is isolated from the outside to avoid sludge and rainwater from affecting the normal use of the reflective photoelectric switch 6. .

The length and width of the circuit board 08 are the same as the size of a single 18650 lithium battery 8, and they are packaged in a sealed box 6. The corresponding core wires are drawn out through the waterproof connector 07, which is connected with the travel switch 5, the reflective optical switch 6, and the solar panel. 10 Make corresponding connections to ensure that the entire circuit device can still work when the manhole cover is soaked in water.

The above structural design is suitable for cast iron manhole covers and steel fiber cement manhole covers; for manhole covers using new composite materials, it is more convenient to carry out an integrated design, and the corresponding light-transmitting composite materials can be directly used to place the circuit device in the inner cavity. in the body. The above structural design, compared with ordinary manhole covers, in addition to lower circuit cost and one-time mold opening cost, the material cost does not increase significantly, which ensures the controllability of the product cost.

To sum up, the present invention proposes an innovation based on the low-power wide area network communication technology LoRa, low-power Bluetooth communication technology BLE, photoelectric sensing technology, low-power consumption technology, etc. An integrated IoT smart manhole cover is developed, which mainly solves the following technical problems:

1) The cost and engineering practicability of the manhole cover monitoring device: fully consider the application environment of the manhole cover, adopt low-power consumption design technology from the overall scheme, and improve and innovate in terms of power supply, wireless communication mode, antenna arrangement, and functional device composition. Solve the drawbacks of the high cost of the current installation and the high cost of postage freight.

2) The effectiveness and real-time performance of the manhole cover monitoring device: Through the photoelectric sensing technology and integrated structure design, the normal state of the manhole cover can be periodically uploaded to the monitoring system according to the setting, and the movement and change of the manhole cover can be accurately judged and can be real-time. Upload to the monitoring system and give an alarm.

3) The Internet of Things function of the manhole cover monitoring device: using LoRa and BLE technology to build a complete Internet of Things monitoring network, not only provides comprehensive monitoring functions for the manhole cover management organization, but also provides on-site and manhole covers for inspection personnel and residents. Communication interconnection , to provide personal query function and status reporting function of manhole cover information status, improve the public's participation and convenience in manhole cover management, and better serve the management of smart cities.

The device of the invention has low manufacturing cost, convenient integrated installation, low daily operation and maintenance cost, strong communication interaction function, and good monitoring real-time performance, and mainly solves the cost and engineering practicability problems of manhole cover monitoring and the Internet of Things linking problem of manhole cover management. It is advanced in overall design and has strong feasibility in project implementation.

The above are only the preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, without departing from the technical principle of the present invention, several improvements and modifications can also be made. These improvements and modifications It should also be regarded as the protection scope of the present invention.

Claims (6)

1. An integrated Internet of things intelligent well lid is characterized by comprising a well lid body and a functional circuit system arranged on the well lid body;

the functional circuit system comprises a well lid position sensor, a controller, a LoRa module and a power supply module;

the controller adopts a Bluetooth system on a chip (BLE SoC) which comprises a Bluetooth wireless transceiving interface and a universal asynchronous receiver/transmitter (UART) interface, wherein the Bluetooth wireless transceiving interface is connected with a Bluetooth antenna, the UART interface is connected with an LoRa module, and the LoRa module is provided with a wireless transceiving antenna; the power supply module provides a working power supply for the well lid position sensor, the controller and the LoRa module;

the manhole cover comprises a manhole cover body, and is characterized in that an antenna installation window is arranged on the manhole cover body, a plurality of reinforcing ribs with two ends fixed in the manhole cover body are arranged on the upper portion of the antenna installation window, a light-transmitting baffle is arranged below each reinforcing rib, and a wireless transceiving antenna of a LoRa module is fixed below each light-transmitting baffle and positioned between vertical direction projections of two adjacent reinforcing ribs;

the well lid position sensor comprises a travel switch arranged at the edge of the well lid, the travel switch comprises a driving ball which can be abutted between the edge of the well lid and the side wall of the well mouth, the change of the pressed state of the driving ball can drive the change of the contact state of the travel switch, and the signal output end of the travel switch is connected with the controller;

the controller also comprises a wake-up pin, and the signal output end of the travel switch is connected with the wake-up pin;

the manhole cover is provided with an opening hole, and an included angle between a connecting line from the travel switch to the center of the manhole cover and a connecting line from the opening hole to the center of the manhole cover is 8-15 degrees;

the well lid position sensor also comprises a reflection-type photoelectric switch arranged at the edge of the well lid, and the connection line of the reflection-type photoelectric switch and the travel switch passes through the center of the well lid; the reflective photoelectric switch senses the distance information between the reflective photoelectric switch and the edge of the wellhead by utilizing the reflection action of the edge of the wellhead and transmits the distance information to the controller;

when the well lid is separated from the well mouth, the pressure state of the driving ball changes to close the travel switch, and the controller wakes up the pin to detect an interrupt signal and enters a working state;

after the controller enters a working state, measuring a current signal output by the reflection-type photoelectric switch: if the measurement result is smaller than the set threshold value, the existence of no reflecting surface or the separation of the reflecting surface is judged, and the detachment of the well cover is confirmed.

2. The intelligent well lid of integration thing networking of claim 1, characterized by also includes RS485 interface circuit module, and the controller still includes the second UART interface, and the controller passes through second UART interface connection RS485 interface circuit module, and then connects external function extension module.

3. The intelligent well lid of integration thing networking of claim 1, characterized by, the wireless transceiver antenna on the loRa module is rod antenna, and the strengthening rib on the antenna installation window is the coplanar mutual parallel arrangement, and the distance between the adjacent strengthening rib is slightly greater than rod antenna's width.

4. The intelligent well lid of integration thing networking of claim 1, characterized by, the strengthening rib on the antenna installation window is the reinforcing bar, and the printing opacity baffle adopts printing opacity glass steel material.

5. The intelligent well lid of integrated thing networking of claim 1, characterized in that, the power module includes solar panel, rechargeable battery and charge management circuit unit; the solar panel is arranged below the light-transmitting baffle of the antenna mounting window; the charging management circuit unit controls the solar panel to charge the rechargeable battery and controls the power supply output of the rechargeable battery.

6. The intelligent well lid of integration thing networking of claim 1, characterized by, well lid edge is equipped with the printing opacity baffle, and the printing opacity baffle is located between reflection type photoelectric switch and well head edge.

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