Ultra-long tunnel health data distributed acquisition system and method thereof

Abstract

The invention relates to an ultra-long tunnel health data distributed acquisition system and method, and the system comprises a data acquisition module which comprises a lifting device disposed on the inner side wall of a tunnel, a lifting frame disposed on the lifting device, and a second control module disposed on the lifting frame, and also comprises a sensor acquisition array unit which is disposed on the same section in the tunnel, the second control module is in communication connection with the acquisition array unit; the positioning identification module is arranged under the lifting device and is used for positioning the corresponding data acquisition module; the data collection robot is used for identifying the positioning identification module and is in communication connection with the second control module; the working base station is arranged beside a tunnel entrance, electrically connected with a tunnel power supply system and in communication connection with the upper control terminal, the working base station is used for routing inspection task distribution, data transmission and energy supplement of the data collection robot, and the problem that when an existing super-long tunnel collects health data, the corresponding networking and power supply building cost is high is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of tunnel health monitoring, and in particular to a distributed collection system and method for health data of an ultra-long tunnel. Background Art

[0002] In tunnel construction and operation and maintenance, real-time monitoring of tunnel structural health is a core technical requirement for ensuring construction safety and operational quality. As transportation infrastructure evolves toward deep, long tunnels, traditional centralized monitoring systems are gradually facing technical bottlenecks. Existing tunnel health monitoring systems typically employ detection modules such as strain gauges, displacement gauges, and pressure cells deployed within the tunnel walls or surrounding rock. These systems utilize wired or wireless networking technologies to establish data transmission channels and utilize centralized power supply systems for continuous monitoring. Although this technical system can realize basic data collection functions, the difficulty of building its technical architecture is very high, and the cost will increase significantly with the length of the tunnel. Specifically, when the tunnel length exceeds 3 kilometers, the traditional bus-type networking solution faces technical bottlenecks such as signal attenuation and transmission delay, resulting in a sharp decline in data transmission stability; secondly, the centralized power supply system needs to lay cables along the entire tunnel. As the tunnel length increases, the line loss increases exponentially, and the power supply reliability is difficult to guarantee; then, when a local fault occurs in the monitoring network, the existing system lacks a rapid positioning mechanism, and fault troubleshooting requires inspection section by section along the tunnel, resulting in low maintenance efficiency. Finally, its cost will also increase exponentially. Therefore, it is urgent to design a health data collection solution for ultra-long tunnels to solve the above problems. Summary of the Invention

[0003] An embodiment of the present invention provides a distributed health data collection system and method for ultra-long tunnels. By arranging data collection modules in a distributed manner, each data collection module is independent of each other. Inspection robots are set up to carry out inspections to obtain data from each data collection module and summarize the data. A working base station is set up at the tunnel entrance to process and report the data, thereby solving the problem of high costs for setting up the corresponding network and power supply when collecting health data in existing ultra-long tunnels.

[0004] A distributed health data collection system for ultra-long tunnels, comprising:

[0005] The data acquisition module includes a lifting device disposed on the inner side wall of the tunnel, a lifting frame disposed on the lifting device, a second control module disposed on the lifting frame, and a sensor acquisition array unit disposed on the same cross section in the tunnel, the second control module being in communication with the acquisition array unit;

[0006] A positioning identification module is provided directly below the lifting device and is used to locate the corresponding data acquisition module;

[0007] A data collection robot, configured to identify the positioning identification module and communicate with the second control module;

[0008] The working base station is set up next to the tunnel entrance, electrically connected to the tunnel power supply system, and communicatively connected to the upper control terminal. The working base station is used for inspection task allocation, data transmission and energy replenishment of the data collection robot.

[0009] Furthermore, the lifting frame includes a channel steel frame composed of two parallel channel steels, and a guide rail is provided on the right side of each channel steel frame, and a rack is provided at a position relative to the front channel steel and the other channel steel. The channel steel frame is set on the tunnel wall, and its top extends to one side of the tunnel top. Two limit frames are provided below the top of the channel steel frame, and a pressure sensor is provided on the limit frame.

[0010] Furthermore, a slider is provided on the right side of the lifting frame, and the slider is slidably set on the guide rail. A mounting groove is provided on the front side of the lifting frame, and a protective cover is detachably provided on the top. The second control module is provided in the mounting groove. A drive motor is provided at the lower right side of the lifting frame. The output shaft of the drive motor passes through the lifting frame, and a transmission gear is provided at its end, which engages with the rack. A power supply module is also provided in the mounting groove, which is used to supply power to the drive motor and the second control module.

[0011] Furthermore, two blocks are provided on the right side of the lifting frame near the top, and a first fixed frame is provided on the left side of the lifting frame near the top. A magnetic plug is provided on the first fixed frame, and the magnetic plug is electrically connected to the second control module. A hub is provided on the top of the channel steel frame near the tunnel wall, and the access end of the hub is connected to the data output end of the sensor acquisition array unit. A second fixed frame is provided between the two limit frames, and a magnetic socket is provided on the second fixed frame. The data output end of the hub is connected to the magnetic socket. When the lifting frame moves to the top end of the channel steel frame, the two blocks respectively conflict with the adjacent limit frames, and at this time the magnetic plug is connected to the magnetic socket.

[0012] Furthermore, the data collection robot includes:

[0013] Multimodal positioning module, used to locate and identify the positioning identification module and obtain the communication port data of the data acquisition module;

[0014] The wireless communication module establishes a communication connection with the data acquisition module based on the communication port data and obtains the detection data;

[0015] The mechanical motion control module is used for the movement control of the data collection robot and the control of the corresponding components of the multimodal positioning module, including the camera.

[0016] Furthermore, the positioning identification module includes a QR code and a UWB positioning beacon.

[0017] Furthermore, the working base station includes:

[0018] Data transmission module, connected to the upper terminal via wire;

[0019] The battery life supplement module is used to charge and extend the battery life of the data collection robot;

[0020] The first control module is used to receive data from the data collection robot and integrate and compress the data.

[0021] In a second aspect, an embodiment of the present invention provides a method for distributed collection of health data in an ultra-long tunnel, comprising the following steps:

[0022] S1, each data acquisition module and positioning identification module is a group, and a group is set every 30-50m in the tunnel;

[0023] S2, the information entered by the positioning identification module includes the location information of the data acquisition module in the tunnel and the communication port data of the data acquisition module;

[0024] S3, setting the inspection task of the data collection robot in the working base station, so that it can inspect according to the task instructions;

[0025] S4, the data collection robot moves to any positioning identification module, performs positioning identification and obtains communication port data;

[0026] S5, sending a wake-up pulse to the second control module based on the communication port data, thereby obtaining health data of the tunnel section;

[0027] S6, repeatedly acquire all data acquisition modules, and return to the working base station after completion;

[0028] S7, transferring the data to the first control module by wireless transmission and replenishing the power;

[0029] S8, the first control module processes the original data, sorts the data based on the location data in the positioning identification module, and finally compresses the data to form a single tunnel detection data packet;

[0030] S9, sends the data packet to the upper control terminal at regular intervals every day.

[0031] The beneficial effects of the above technical solutions provided by the embodiments of the present invention include at least:

[0032] By deploying independent data acquisition modules at intervals in the tunnel, each module integrates multi-type sensor arrays and near-field communication units. Each data acquisition module corresponds to a positioning identification module, which integrates QR codes and UWB beacons to facilitate the inspection robot to determine the location information corresponding to each data acquisition module. The inspection robot is equipped with a multimodal positioning system. When moving autonomously along the tunnel, it locates the target module through visual recognition or ultra-wideband signals, and then uses wireless communication to wake up the corresponding acquisition unit. This process realizes the decoupling of each positioning identification module and the data acquisition module. Any failure will not affect the overall data collection. After the data acquisition is completed, it returns to the working base station at the tunnel entrance. The base station integrates and compresses the raw data in time and space, and finally forms a standardized data packet and uploads it to the control center. This distributed architecture breaks through the limitations of traditional bus-type networking. Each module operates independently to avoid the spread of single-point failures, reduce the wiring cost of the entire line, and effectively solve the technical bottlenecks faced by ultra-long tunnel monitoring, such as signal attenuation, power supply difficulties and inefficient maintenance.

[0033] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purposes and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings.

[0034] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0036] Figure 1 This is a schematic structural diagram of Example 1 disclosed in the embodiments of the present invention;

[0037] Figure 2 A schematic diagram of the structure of a working base station and a data collection robot disclosed in an embodiment of the present invention;

[0038] Figure 3 This is a structural diagram of a data acquisition module disclosed in an embodiment of the present invention from a first perspective;

[0039] Figure 4 This is a structural diagram of a data acquisition module from a second perspective disclosed in an embodiment of the present invention;

[0040] Figure 5 A schematic structural diagram of a data acquisition module from a third perspective disclosed in an embodiment of the present invention;

[0041] Figure 6A communication block diagram disclosed in an embodiment of the present invention;

[0042] Figure 7 This is a flow chart of the method disclosed in an embodiment of the present invention.

[0043] Reference numerals:

[0044] 10. Working base station; 11. Data transmission module; 12. Endurance supplement module; 13. First control module; 20. Data collection robot; 21. Multimodal positioning module; 22. Wireless communication module; 23. Mechanical motion control module; 30. Data acquisition module; 31. Lifting frame; 3101. Slider; 3102. Drive motor; 3103. Block; 3104. First fixed frame; 32. Second control module; 3201. Near-field communication unit; 33. Power module; 34. Lifting device; 3401. Channel steel frame; 3402. Rack; 3403. Limiting frame; 34031. Second fixed frame; 3404. Pressure sensor; 35. Magnetic plug; 36. Magnetic socket; 37. Hub; 38. Sensor acquisition array unit; 40. Positioning identification module. DETAILED DESCRIPTION

[0045] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0046] Example 1

[0047] like Figure 1 As shown, an embodiment of the present invention provides a distributed health data collection system for ultra-long tunnels, comprising:

[0048] The data acquisition module 30 includes a lifting device 34 installed on the inner side wall of the tunnel. The lifting device 34 is equipped with a lifting frame 31, and the lifting frame 31 is equipped with a second control module 32. It also includes a sensor acquisition array unit 38. The sensor acquisition array unit 38 includes several types of sensors (such as concrete strain gauges, static level gauges, multi-point displacement gauges, convergence meters, earth pressure gauges, piezometers, etc.) pre-buried in the tunnel or installed on the tunnel side wall. These sensors are installed on the same cross-section in the tunnel and communicate with the acquisition array unit through the second control module 32. The data from these sensors is summarized, which represents the health data of the tunnel section.

[0049] It should be noted that the second control module 32 has a near field communication unit 3201 , and its maximum communication distance is 5-10 m.

[0050] like Figure 3-5 As shown, the lifting frame 31 includes a channel steel frame 3401 composed of two parallel channel steels, and a guide rail is provided on the right side of each channel steel frame 3401, and a rack 3402 is provided at a position relative to the other channel steel on the front side. The channel steel frame 3401 is set on the tunnel wall, and its top extends to one side of the tunnel top. Two limit frames 3403 are provided below the top of the channel steel frame 3401, and a pressure sensor 3404 is provided on the limit frame 3403. The pressure sensor 3404 is electrically connected to the third controller.

[0051] In this embodiment, a slider 3101 is provided on the right side of the lifting frame 31, and the slider 3101 is slidably set on the guide rail. A mounting slot is provided on the front side of the lifting frame 31, and a protective cover is detachably provided on the top. When the protective cover is opened, a second control module 32 is provided in the mounting slot, and a power supply module 33 is also provided inside. The power supply module 33 is used to supply power to the second control module 32. A drive motor 3102 is provided at the lower right side of the lifting frame 31 (i.e., below the mounting slot). The output shaft of the drive motor 3102 passes through the lifting frame 31, and a transmission gear is provided at its end. The transmission gear is engaged with the rack 3402, and the second control module 32 is electrically connected to the drive motor 3102.

[0052] In this embodiment, two blocks 3103 are provided on the right side of the lifting frame 31 near the top, a first fixing frame 3104 is provided on the left side near the top, a magnetic plug 35 is provided on the first fixing frame 3104, a through hole is provided on the front side of the lifting frame 31, a data line extends from the third controller through the through hole and is connected to the magnetic plug 35, a hub 37 is provided on the top side of the channel steel frame 3401 near the tunnel wall, the access end of the hub 37 is connected to the data output end of the sensor acquisition array unit 38, since the sensor acquisition array unit 38 has many sensor types, the corresponding ports are also different, and the sensor line type selected is determined based on the selected sensor line type. A hub 37 that matches the system ensures convenient wiring between the third control unit and several sensors. A second fixing frame 34031 is set between the two limit frames 3403, and a magnetic socket 36 is set on the second fixing frame 34031. The data output end of the hub 37 is connected with the magnetic socket 36. When the lifting device 34 needs to move to the end, the drive motor 3102 is controlled to rotate, so that it moves upward based on the action of the transmission gear and the rack 3402. When the two blocks 3103 conflict with the limit frames 3403, the pressure sensor 3404 transmits a signal to the second control module 32 to stop the drive motor 3102. At this time, the magnetic plug 35 is connected to the magnetic socket 36.

[0053] In this solution, the data acquisition module 30 is set to a structure that can be raised in height mainly to avoid being set close to the ground and easily scratched by non-staff or vehicles, causing equipment damage and casualties. Secondly, compared with a fixed setting on the top of the tunnel, it is not convenient for subsequent maintenance.

[0054] like Figure 1 As shown, the positioning identification module 40 is arranged directly below the lifting device 34 and is used to locate the corresponding data acquisition module 30. It includes a QR code and a UWB positioning beacon. The data identified by these three identification units all contain the communication port data corresponding to the near-field communication unit 3201 in the second control module 32.

[0055] like Figure 2 As shown, the data collection robot 20 is used to identify the positioning identification module 40 and communicate with the second control module 32, specifically including:

[0056] The multimodal positioning module 21 is used to locate and identify the positioning identification module 40 and obtain the communication port data of the data acquisition module 30;

[0057] The wireless communication module 22 establishes a communication connection with the data acquisition module 30 based on the communication port data and obtains the detection data;

[0058] The mechanical motion control module 23 is used for the movement control of the data collection robot 20 and the control of the corresponding components of the multimodal positioning module 21, including the camera.

[0059] Specifically, the data collection robot 20 moves to the vicinity of the positioning identification module 40, and mainly relies on the camera to identify the QR code or ultra-wideband identification UWB positioning beacon on the target positioning identification module 40, thereby parsing the message data therein, and then parsing and obtaining the communication port data. At this time, the wireless communication module 22 sends a detection packet to the communication port data, and then wakes up the second control module 32 to execute the data transmission protocol. When the data transmission is completed, the data collection robot 20 moves to the next positioning identification module 40 and repeats the operation. After all data synchronization is completed, it returns to the working base station 10.

[0060] In this solution, the exception handling mechanism is that if the detection packet is timed out three times, it means that the data acquisition module 30 at that location is faulty, so the data is marked as abnormal.

[0061] In this embodiment, the working base station 10 is located near the tunnel entrance, is electrically connected to the tunnel power supply system, and is in communication with the upper control terminal. The working base station 10 is used for patrol task allocation, data transmission, and energy replenishment of the data collection robot 20. Specifically, it includes:

[0062] The data transmission module 11 preferably uses a wired connection mode for communication, as most tunnels are located in mountainous areas with weak wireless signals, and wired connection mode is more stable for data transmission;

[0063] The battery life supplement module 12 is used to charge the data collection robot 20 for battery life, mainly using wireless charging;

[0064] The first control module 13 is used to receive data from the data collection robot 20 and integrate and compress the data.

[0065] Example 2

[0066] The embodiment of the present invention also discloses a distributed collection method for health data of ultra-long tunnels, such as Figure 2 , including the following steps:

[0067] S1, each data acquisition module 30 and positioning identification module 40 is a group, and a group is set every 30-50m in the tunnel;

[0068] S2, the information entered by the positioning identification module 40 includes the location information of the data acquisition module 30 in the tunnel and the communication port data of the data acquisition module 30;

[0069] S3, setting the inspection task of the data collection robot 20 in the working base station 10, so that it inspects according to the task instructions;

[0070] S4, the data collection robot 20 moves to any positioning identification module 40, performs positioning identification and obtains communication port data;

[0071] S5, sending a wake-up pulse to the second control module 32 based on the communication port data, thereby obtaining the health data of the tunnel section;

[0072] S6, repeatedly acquire all data acquisition modules 30, and return to the working base station 10 after completion;

[0073] S7, transferring the data to the first control module 13 by wireless transmission and replenishing the power;

[0074] S8, the first control module 13 processes the original data, sorts the data based on the location data in the positioning identification module 40, and finally compresses the data to form a single tunnel detection data packet;

[0075] S9, sends the data packet to the upper control terminal at regular intervals every day.

[0076] It should be understood that the specific order or hierarchy of steps in the disclosed processes is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process can be rearranged without departing from the scope of the present disclosure. The accompanying method claims present elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy described.

[0077] In the foregoing detailed description, various features are grouped together in a single embodiment to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that embodiments of the claimed subject matter require more features than are expressly recited in each claim. On the contrary, as reflected in the appended claims, the invention comprises less than all the features of any individual disclosed embodiment. The appended claims are therefore hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

[0078] Those skilled in the art will also appreciate that the various illustrative logic blocks, modules, circuits, and algorithmic steps described in conjunction with the embodiments herein may be implemented as electronic hardware, computer software, or a combination thereof. In order to clearly illustrate the interchangeability between hardware and software, the various illustrative components, blocks, modules, circuits, and steps described above are generally described around their functions. Whether such functions are implemented as hardware or software depends on the specific application and the design constraints imposed on the entire system. A skilled person may implement the described functions in an adaptable manner for each specific application, but such implementation decisions should not be interpreted as departing from the scope of protection of this disclosure.

[0079] The steps of the methods or algorithms described in conjunction with the embodiments herein may be directly embodied as hardware, software modules executed by a processor, or a combination thereof. The software module may be located in a RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, register, hard disk, removable disk, CD-ROM, or any other form of storage medium well known in the art. An exemplary storage medium is connected to the processor so that the processor can read information from the storage medium and write information to the storage medium. Of course, the storage medium may also be an integral part of the processor. The processor and storage medium may be located in an ASIC. The ASIC may be located in a user terminal. Of course, the processor and storage medium may also be present in a user terminal as discrete components.

[0080] For software implementation, the techniques described in this application can be implemented using modules (e.g., procedures, functions, etc.) that perform the functions described in this application. These software codes can be stored in a memory unit and executed by a processor. The memory unit can be implemented within the processor or external to the processor. In the latter case, it is communicatively coupled to the processor via various means, which are well known in the art.

[0081] The foregoing description includes examples of one or more embodiments. Of course, it is not possible to describe all possible combinations of components or methods for the purposes of describing the above embodiments, but one of ordinary skill in the art will recognize that the various embodiments may be further combined and arranged. Therefore, the embodiments described herein are intended to encompass all such changes, modifications and variations that fall within the scope of the appended claims. Furthermore, to the extent the term "comprising" is used in the specification or claims, the term is intended to be encompassed in a manner similar to the term "including," as if "including" were used as a transitional word in the claims. Furthermore, any use of the term "or" in the specification of the claims is intended to mean a "non-exclusive or."

Claims

1. A distributed health data collection system for ultra-long tunnels, characterized by: include: The data acquisition module includes a lifting device disposed on the inner side wall of the tunnel, a lifting frame disposed on the lifting device, a second control module disposed on the lifting frame, and a sensor acquisition array unit disposed on the same cross section in the tunnel, the second control module being in communication with the acquisition array unit; A positioning identification module is provided directly below the lifting device and is used to locate the corresponding data acquisition module; A data collection robot, configured to identify the positioning identification module and communicate with the second control module; The working base station is set up next to the tunnel entrance, electrically connected to the tunnel power supply system, and communicatively connected to the upper control terminal. The working base station is used for inspection task allocation, data transmission and energy replenishment of the data collection robot.

2. The ultra-long tunnel health data distributed collection system according to claim 1, characterized in that: The lifting frame includes a channel steel frame composed of two parallel channel steels, and a guide rail is provided on the right side of each channel steel frame. A rack is provided at the position relative to the front channel steel and the other channel steel. The channel steel frame is set on the tunnel wall, and its top extends to one side of the tunnel top. Two limit frames are provided below the top of the channel steel frame, and pressure sensors are provided on the limit frames.

3. The ultra-long tunnel health data distributed collection system according to claim 2, characterized in that: A slider is provided on the right side of the lifting frame, and the slider is slidably set on the guide rail. A mounting slot is provided on the front side of the lifting frame, and a protective cover is detachably provided on the top. The second control module is provided in the mounting slot. A drive motor is provided at the lower right side of the lifting frame. The output shaft of the drive motor passes through the lifting frame, and a transmission gear is provided at its end. The transmission gear is engaged with the rack. A power supply module is also provided in the mounting slot, which is used to power the drive motor and the second control module.

4. The ultra-long tunnel health data distributed collection system according to claim 3, characterized in that: Two blocks are provided on the right side of the lifting frame near the top, and a first fixed frame is provided on the left side of the lifting frame near the top. A magnetic plug is provided on the first fixed frame, and the magnetic plug is electrically connected to the second control module. A hub is provided on the top of the channel steel frame near the tunnel wall. The access end of the hub is connected to the data output end of the sensor acquisition array unit. A second fixed frame is provided between the two limit frames, and a magnetic socket is provided on the second fixed frame. The data output end of the hub is connected to the magnetic socket. When the lifting frame moves to the top end of the channel steel frame, the two blocks respectively conflict with the adjacent limit frames, and at this time the magnetic plug is connected to the magnetic socket.

5. The ultra-long tunnel health data distributed collection system according to claim 1, characterized in that: Data collection robots include: Multimodal positioning module, used to locate and identify the positioning identification module and obtain the communication port data of the data acquisition module; The wireless communication module establishes a communication connection with the data acquisition module based on the communication port data and obtains the detection data; The mechanical motion control module is used for the movement control of the data collection robot and the control of the corresponding components of the multimodal positioning module, including the camera.

6. The ultra-long tunnel health data distributed collection system according to claim 1, characterized in that: The positioning identification module includes a QR code and a UWB positioning beacon.

7. The ultra-long tunnel health data distributed collection system according to claim 1, characterized in that: The working base station includes: Data transmission module, connected to the upper terminal via wire; The battery life supplement module is used to charge and extend the battery life of the data collection robot; The first control module is used to receive data from the data collection robot and integrate and compress the data.

8. A method for distributed collection of health data in ultra-long tunnels, using the distributed collection system for health data in ultra-long tunnels according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1, each data acquisition module and positioning identification module is a group, and a group is set every 30-50m in the tunnel; S2, the information entered by the positioning identification module includes the location information of the data acquisition module in the tunnel and the communication port data of the data acquisition module; S3, setting the inspection task of the data collection robot in the working base station, so that it can inspect according to the task instructions; S4, the data collection robot moves to any positioning identification module, performs positioning identification and obtains communication port data; S5, sending a wake-up pulse to the second control module based on the communication port data, thereby obtaining health data of the tunnel section; S6, repeatedly obtain all data acquisition modules, and return to the working base station after completion; S7, transferring the data to the first control module by wireless transmission and replenishing the power; S8, the first control module processes the original data, sorts the data based on the location data in the positioning identification module, and finally compresses the data to form a single tunnel detection data packet; S9, sends the data packet to the upper control terminal at regular intervals every day.

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