Node instrument field positioning and tracking method

Abstract

The invention discloses a field positioning and tracking method for a node instrument, which is a method for efficiently positioning and tracking a field Bluetooth type earthquake node instrument by combining an unmanned aerial vehicle, and is characterized in that a technical method for optimizing Bluetooth distance measurement is innovatively transplanted to a field random environment; software and hardware such as an unmanned aerial vehicle, intelligent equipment, a Beidou probe, a ground computer, a CORS positioning service, a distance measurement program, a synchronous monitoring and control program and the like are utilized to construct a ground-air integrated node instrument searching platform. Through full research and test in a plurality of seismic acquisition items, the positioning and tracking technical method is realized, so that the node instrument searching efficiency can be greatly improved, the personnel and searching cost can be saved, the equipment loss risk can be reduced, the integrity and safety of seismic acquisition data can be effectively improved, and the method is suitable for popularization and application. And the industrial and agricultural contradiction is relieved, construction blocking and field risk points are reduced, project safety management improvement is promoted, and a good effect is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of oil and gas exploration, and in particular to a method for field positioning and tracking of a Bluetooth-type seismic node instrument in combination with an unmanned aerial vehicle. Background Art

[0002] At present, wireless node instruments have begun to be widely used in seismic acquisition production, playing an important role in improving quality, speed and efficiency, but there are also the following problems:

[0003] 1) Field nodes are easily lost (tilted, blocked, stolen or hidden, satellite signal lost, etc.)

[0004] 2) Lost nodes are difficult to find (blocked by ground obstacles, limited search range, blocked by worker-farmer relations, etc.);

[0005] 3) Low search efficiency (limited by manual mode, positioning method and efficiency, local coordination, etc.);

[0006] 4) High search costs (input of personnel and vehicles, relationship coordination, handling of conflicts between workers and farmers, delays in collecting teams, etc.);

[0007] 5) If the data cannot be retrieved, the loss will be huge and the risk will be high (integrity and security of seismic data, conflicts between workers and farmers, equipment loss, etc.)

[0008] In order to solve these problems, it is necessary and urgent to study a positioning and tracking technology to achieve fast and efficient search for lost node instruments in the field.

[0009] Given that the current major seismic node instrument products are equipped with low-power Bluetooth functions to wirelessly send device health status information. As long as the node instrument battery is not depleted, even if it cannot provide coordinates and other information in some special circumstances (such as tilt, occlusion, etc. causing satellite signal loss), it can still transmit Bluetooth wireless signals and continue to work for a long time. Based on this feature of Bluetooth, a method for fast and efficient positioning and tracking of lost node instruments in the field was studied. Summary of the invention

[0010] The present invention provides a method for field positioning and tracking of Bluetooth-based seismic node instruments, which is used to solve the problems of low efficiency and high cost in manually searching for lost node instruments in the field. Technical solution:

[0011] Step 101: Optimize Bluetooth ranging technology using radio wave propagation loss and measured correction model, use filtering algorithm to reduce Bluetooth signal multipath interference, independently write Bluetooth ranging software, and load it into smart devices with Super Bluetooth, and then use Beidou probe antenna and CORS positioning service of Qianxun Location Company;

[0012] Step 102: Using a drone equipped with the smart device, design a straight line route in any direction in an area where a node meter may exist, hereinafter referred to as the first route, to search for the Bluetooth signal of the target node meter in the air and continuously measure the distance;

[0013] Step 103: The ground monitoring station synchronously observes and controls, and the Bluetooth distance of the target node instrument on the first route will change from "far-near-far". The operator guides the UAV to fly to the point where the Bluetooth signal is the strongest (i.e., the closest point);

[0014] Step 104: Control the drone to turn 90 degrees in the air at this point and continue searching along the vertical route. The Bluetooth distance of the target node will also change from "far-near-far". Find the point with the strongest Bluetooth signal (i.e. the closest point) again, that is, reach directly above the target node.

[0015] Step 105: The ground monitoring station controls the ranging program to record the coordinates of the point and send them to the ground personnel. The ground personnel use the coordinates to navigate to the point and track the target node instrument.

[0016] Furthermore, the algorithm formula of the radio wave propagation loss and measured correction model in step 101 is:

[0017] Path loss L (dB) = 32.45 + 20logD (km) + 20logF (MHz) + C.

[0018] Where: F is the operating frequency, unit is MHz, Bluetooth is generally 2400MHz or 5000MHz; D is the transmission distance, unit is km, C is the local measured correction number, unit is dB.

[0019] In addition, based on the analysis of the shortest line segment principle in the same plane, the false signal generated by the Bluetooth multipath effect has a longer propagation path, a weaker signal, and a larger calculated distance. Therefore, the method of taking the minimum value of multiple groups of observations in a short time can be implemented using the function MIN(D1, D2...), and the program repeatedly uses this algorithm to filter out obvious jump values ​​and false values ​​and reduce multipath interference. The smart devices involved, such as mobile phones and tablets, must contain X-BT super Bluetooth chips to ensure a communication distance of more than 80 meters, and can install Bluetooth ranging programs / algorithms (including radio wave propagation loss and measured correction models, as well as filtering algorithms), read the MAC address and ranging of the target node instrument, and then match the Beidou probe antenna and CORS positioning service to ensure their own positioning accuracy.

[0020] Furthermore, the step 102 of using a drone to carry a smart device specifically includes:

[0021] Multi-rotor drones (such as M300RTK) are preferred. The smart device equipped with the Bluetooth ranging program should be correctly and firmly mounted on the drone. The drone's radar and satellite antenna sensors should not be blocked to avoid affecting their performance. The Bluetooth ranging software should be installed on the smart device and run normally. Both the smart device and the ground monitoring station computer should provide 4G network conditions. Use remote control programs such as Airdroid, and use ground computers to connect to the network and remotely manage the aerial smart device, so as to achieve synchronous observation and control of the ground monitoring station, so as to monitor the real-time situation of aerial node ranging and various operations such as program switching, data acquisition, and sending.

[0022] Further, in step 103, the Bluetooth ranging corresponding signal strength change of the target node instrument on the first route specifically includes:

[0023] According to the radio wave propagation loss and measured correction model, when the drone equipped with smart devices approaches the target node instrument, the measured Bluetooth signal distance will become smaller, and vice versa, it will become larger, corresponding to the increase and decrease of the Bluetooth signal strength. Although the target node instrument is not necessarily on the first route, according to the radio theory and spatial analytic geometry mathematical principles, the Bluetooth ranging data of the target node instrument has a corresponding relationship with the signal strength. Based on this, finding the strongest signal point on the first route completes the first step of tracking and positioning the target node instrument.

[0024] Further, in step 104, the search is continued along the vertical route at the location where the signal of the first route is the strongest, specifically including:

[0025] Through mathematical calculation and derivation, the vertical route of the first route is set at the point where the Bluetooth distance measurement of the target node instrument is closest (corresponding to the point where the Bluetooth signal is the strongest) on the first route, that is, at this point the drone turns 90 degrees in the air to continue searching, and the target node instrument is theoretically on this route. The Bluetooth distance measurement for this node instrument will also change from "far-near-far" (corresponding to the Bluetooth signal is "weak-strong-weak"), and the closest point (that is, the point where the Bluetooth signal is the strongest) is found again, that is, it reaches directly above the target node instrument.

[0026] Further, in step 105, the ground monitoring station records the coordinates of the point and sends them to the ground personnel, which specifically includes:

[0027] Utilizing the remote real-time synchronous observation and control function of the ground monitoring station, technicians can instantly analyze the ranging information of the intelligent devices on the drone, acquire, store and transmit the data during the search process at any time, and transmit the coordinate data to ground support personnel, so that dispatchers can quickly and efficiently complete the node positioning and tracking work.

[0028] Beneficial Effects of the Invention

[0029] The present invention provides a method for field positioning and tracking of Bluetooth-type seismic node instruments. By optimizing Bluetooth ranging and reducing multipath interference, the technology is innovatively transplanted into a random field environment, and a ground-to-air node instrument search platform is built by using multi-rotor drones, smart devices with super Bluetooth chips, Beidou probes of Qianxun Location Company, ground computer monitoring stations, mobile CORS positioning services, self-written ranging programs, and ground-to-air synchronous monitoring and control programs and other software and hardware. Through sufficient research, experiments and tests in multiple seismic acquisition projects, the positioning and tracking technical method has been realized, solving the problems of low efficiency, high cost, and great safety hazards of traditional manual search, and the effect is obvious in project production practice.

[0030] 1) Improved efficiency, reduced personnel, reduced costs and equipment risks.

[0031] Through the test and comparison of the full manual mode and the new search mode of a project in Jiangsu Province, the "triangulation orientation + cross positioning method" is 6.67 times more efficient than the full manual mode. After the project is promoted, it can reduce 70% of search personnel and save 81.4% of search costs, and the effect of technology empowerment is significant. In addition, as of the end of March 2024, in the process of testing this method in the project, 240 node instruments of various types that could not be detected manually on the ground have been recovered, with a total equipment value of about 650,000 yuan. The application of new technology reduces the risk of equipment loss.

[0032] 2) Improved the integrity and security of seismic acquisition data and reduced quality risks.

[0033] By recovering the lost nodes, the important acquisition data attached to them was saved, the number of effective acquisition channels was increased, the data integrity and security were improved, and the project quality risk was reduced. For example, during the project technical testing process, the 240 lost nodes recovered corresponded to 180,000 non-repeated channels of a project in northern Jiangsu, which can increase the data integrity rate (or recovery rate) by 0.13%, which is of great significance to the improvement of seismic acquisition data quality.

[0034] 3) It eases conflicts between workers and farmers, reduces construction obstruction incidents, and is also beneficial to environmental protection.

[0035] The new node positioning and tracking technology uses drones to search for nodes from the air, which can reduce the activities of ground search personnel and avoid damage to crops and vegetation in the fields. It effectively eases the conflicts between workers and farmers, is also beneficial to environmental protection, and thus reduces the number of incidents of villagers obstructing earthquake construction, promotes the efficient operation of the project, and also has a positive impact on the later series of construction work in the oil field.

[0036] 4) Reduced risk points in the field and promoted improved safety management.

[0037] During the seismic production process, every person and every vehicle in the field is a safety risk point. The use of new node positioning and tracking technologies reduces the number of people and vehicles searching for nodes in the field, promotes the improvement of field safety management of seismic projects, helps the safety management of oil fields, and highlights the safety responsibility of enterprises. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 Schematic diagram of the process of a node device positioning and tracking method according to an embodiment of the present invention.

[0039] Figure 2 Schematic diagram of the operation of the node instrument positioning and tracking method according to an embodiment of the present invention.

[0040] Figure 3 A schematic diagram of a target node on the first route side according to an embodiment of the present invention

[0041] Figure 4 A schematic diagram of a target node meter directly below a route according to an embodiment of the present invention DETAILED DESCRIPTION

[0042] The present invention will be further described below in conjunction with embodiments, but the protection scope of the present invention is not limited thereto:

[0043] The execution subject of this embodiment is the positioning and tracking of the outdoor Bluetooth node instrument.

[0044] Combination Figure 1 and Figure 2 The present invention provides a method for field positioning and tracking of a node instrument, comprising:

[0045] Step 101: Optimize the Bluetooth ranging technology using radio wave propagation loss and measured correction models, use filtering algorithms to reduce Bluetooth signal multipath interference, independently write Bluetooth ranging software, and load it into a smart device with Super Bluetooth (preferably, a smart Android device), and then use it with the Beidou probe antenna and CORS positioning service of Qianxun Location Company.

[0046] Specifically, the radio wave propagation loss model is optimized, and the correction number C is obtained by using local measured data. For example, the distance of the known ground target node instrument is 10, 50, and 100 meters, and a local environmental correction model is established. The difference between the measured theoretical model and the actual distance is calculated, and the correction number C is obtained by deduction, and the theoretical formula is added to improve the ranging accuracy. The minimum value filtering method is a scheme that uses the minimum value of multiple groups of distance observation values ​​in a short period of time. For example, 5 groups of Bluetooth ranging data in a short period of time can be taken, and the minimum ranging value and the corresponding drone position coordinates are taken to participate in the calculation to reduce multipath interference. The DJI M300RTK drone is preferred, and its ability to search for the Bluetooth signal of the ground node instrument for a long time is used. Smart Android mobile phone devices with X-BT super Bluetooth chips are preferred to ensure sufficient signal reception distance (more than 80 meters) so that the drone can avoid most ground obstacles. The Beidou probe and CORS positioning service of Qianxun Location Company are preferred to provide centimeter-level positioning for smart devices and improve ranging accuracy. The above work provides a guarantee for the construction of a node instrument search platform.

[0047] Step 102: Using a drone equipped with the smart device, design a straight line route in any direction in an area where a node meter may exist, hereinafter referred to as the first route, to search for the Bluetooth signal of the target node meter in the air and continuously measure the distance.

[0048] Specifically, various software and hardware are integrated into the drone platform, such as installing Beidou probes and self-developed Bluetooth ranging programs on smart devices, opening CORS positioning services, and securely mounting smart devices on drones. Be careful not to block the drone's satellite antenna and various sensors such as radars to prevent affecting their performance. Both smart devices and ground monitoring station computers are connected to the 4G network environment, and remote control programs such as Airdroid are installed. Ground computers are used to connect to the network and remotely manage aerial smart devices to monitor the real-time changes in the ranging of aerial nodes on the first route, as well as to start and close the program, record data, share and send, and other operations, so as to achieve synchronous observation and control by the ground monitoring station.

[0049] Step 103, the ground monitoring station synchronously observes and controls, and the Bluetooth distance of the target node instrument on the first route will change from "far-near-far". The operator guides the UAV to the point where the Bluetooth signal is the strongest (i.e., the closest point).

[0050] Specifically, as the Bluetooth signal distance measurement for the same target node is continuously carried out, the ground monitoring station will observe regular data changes. If the distance data is connected, a parabola will be formed, and its shape will be inversely proportional to the parabola formed by the DB value data. The lowest point of the distance data parabola, corresponding to the highest point of the DB data parabola, is the strongest point of the Bluetooth signal, which is also the closest point to the target node.

[0051] According to the mathematical principles of spatial analytic geometry, such as Figure 2 On the first-line route and the vertical route, the point with the strongest Bluetooth signal is found according to the changes in the "far-near-far" Bluetooth ranging of the target node instrument, and finally the positioning and tracking of the node instrument is realized. The two routes cross vertically to form a cross, and the symmetrical points with equal signal strength on the first-line route on both sides of the point form an isosceles triangle with the position of the node instrument, just like an arrow pointing to the position of the node instrument. Therefore, this technical method is summarized as "triangle orientation + cross positioning method".

[0052] Its basic positioning principle comes from the flexible application of the edge (distance) intersection method in space geometry. The schematic diagram and proof algorithm are as follows: Figure 3 and Figure 4 First, we use the two known coordinate points A and B on the first route, which are at the same distance from the drone to the node instrument point P (that is, the same Bluetooth signal strength) (the coordinates can be obtained in real time from smart Android mobile devices. Since smart devices are equipped with Beidou probe antennas and CORS positioning services of Qianxun Location Company, centimeter-level positioning accuracy can be achieved), and use the cosine theorem to calculate the angle A:

[0053]

[0054] Let: u=a cosA

[0055]

[0056] Then the coordinates of the target node point P can be calculated:

[0057] x p =x A +u cosa AB +v sina AB

[0058] y p =y A +u sina AB -v cosa AB

[0059] Note: In the above formula, point P is on the left side of line segment AB (A, B, and P form a triangle counterclockwise). If the point P to be determined is on the right side of line segment AB (A, B, and P form a triangle clockwise), the formula is adjusted to:

[0060] x p =x A +u cosa AB -v sina AB

[0061] y p =y A+u sina AB +v cosa AB

[0062] From the analysis, we know that if there are only two known points, A and B, there are two position solutions for point P calculated using the distance intersection method (symmetrically distributed on both sides of the first route). Therefore, it is necessary to set the vertical route OP or PO of the first route on the perpendicular bisector PO of the isosceles triangle PAB, and fly from point O in the direction of OP. If the Bluetooth distance measurement is getting closer (the signal becomes stronger), it proves that the direction is correct. Otherwise, it should fly in the opposite direction of PO. In the actual UAV flight process, the Bluetooth distance measurement program will continuously re-measure the distance, and combined with the continuously obtained UAV positioning data, guide the operator to continuously approach the target position.

[0063] Step 104: Control the drone to turn 90 degrees in the air at this point and continue searching along the vertical route. The Bluetooth distance of the target node will also change from "far-near-far". Find the point with the strongest Bluetooth signal (i.e. the closest point) again, that is, reach directly above the target node.

[0064] Specifically, after finding the closest point to the target node on the first route, the drone is controlled to adjust the heading by 90 degrees and continue searching along the vertical route. Through mathematical derivation and calculation, the target node is theoretically on this vertical route, and the Bluetooth distance measurement for this node will also have a parabolic change of "far-near-far" (corresponding to the Bluetooth signal is "weak-strong-weak"), and the closest point is found again (that is, the strongest point of the Bluetooth signal on the vertical route), that is, it reaches directly above the target node.

[0065] Step 105: The ground monitoring station controls the ranging program to record the coordinates of the point and send them to the ground personnel. The ground personnel use the coordinates to navigate to the point and track the target node instrument.

[0066] Specifically, the technicians at the ground monitoring station can use the Bluetooth ranging program to obtain the coordinates of the target node instrument. Since the UAV route is designed according to the terrain simulation flight, the elevation of this point is generally 80 meters different from the ground. After the coordinate data is sent to the ground support personnel, they can find the target node instrument by using its plane coordinates for navigation and tracking.

[0067] Although the present invention has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced by equivalents without departing from the scope of the present invention. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there is no logical conflict. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A method for field positioning and tracking of node instruments, characterized in that Combined with drones, it can track the Bluetooth node instrument when satellite positioning is unavailable in the field, including: Step 101: Select a smart device with Super Bluetooth, and match it with Beidou probe antenna and CORS positioning service; the smart device is loaded with a Bluetooth ranging algorithm, and the Bluetooth ranging algorithm includes a radio wave propagation loss and a measured correction model, as well as a filtering algorithm; Step 102: Using a drone equipped with the smart device, design a straight line in any direction as the first route in an area where a node meter may exist, search for the Bluetooth signal of the target node meter in the air and continuously measure the distance; Step 103: The ground monitoring station synchronously observes and controls, and the Bluetooth distance of the target node instrument on the first route will change from "far-near-far". The operator guides the UAV to the point where the Bluetooth signal is the strongest, that is, the closest point; Step 104: Control the drone to turn 90 degrees in the air at this point and continue searching along a vertical route perpendicular to the first route. The Bluetooth distance of the target node will also change from "far-near-far". Find the point with the strongest Bluetooth signal, which is the closest point, and reach the top of the target node. Step 105: The ground monitoring station records the coordinates of the point and sends them to the ground personnel, who use the coordinates to navigate to the point, thus completing the positioning and tracking of the target node instrument.

2. The method according to claim 1, characterized in that The algorithm formula of the radio wave propagation loss and measured correction model described in step 101 is: Path loss L (dB) = 32.45 + 20logD (km) + 20logF (MHz) + C Where: F is the operating frequency, unit MHz; D is the transmission distance, unit km; C is the local measured correction number, unit dB; Using the above algorithm, the distance D can be derived and calculated when the path loss L, operating frequency F and local measured correction number C are known.

3. The method according to claim 1, characterized in that The minimum filtering algorithm is adopted to obtain the minimum value of multiple groups of observation values ​​in a short period of time, and this process is repeated continuously to filter out the jump values ​​and false values ​​of the Bluetooth signal and reduce multipath interference.

4. The method according to claim 1, characterized in that The Bluetooth ranging algorithm can read the MAC address and ranging of the target node instrument, and set the local measured correction number as a variable, which is input at the beginning of the ranging program. The user needs to measure and update the model correction number in time according to different electromagnetic environments.

5. The method according to claim 1, characterized in that Smart devices must be equipped with an X-BT super Bluetooth chip with a communication distance greater than 80 meters, and be equipped with a Beidou probe antenna and CORS positioning service.

6. The method according to claim 1, characterized in that The drone device described in step 102 is a multi-rotor drone, which is equipped with an intelligent device to search for node instrument signals, and the flight altitude is not less than 80 meters to avoid most ground obstacles.

7. The method according to claim 1, characterized in that The ground monitoring synchronous observation and control described in step 103 includes specific hardware and software: the aerial intelligent device and the ground monitoring station computer are both installed with synchronization software and equipped with 4G network, thereby realizing ground-air synchronous monitoring and control, real-time monitoring of the continuous changes in the Bluetooth ranging data of the aerial Android device, and performing necessary control operations on the Android device.

8. The method according to claim 1, characterized in that The ground monitoring station described in step 105 records the coordinates of the point. Specifically, the Bluetooth ranging algorithm supports point recording. When the UAV arrives directly above the node instrument, the coordinates of the point are obtained in time, stored, and transmitted back, and sent to the designated ground support personnel. The support personnel use the plane coordinates to navigate to the point and successfully find the target node instrument.

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