Parking space positioning method based on wheel speed distance measurement and application thereof

Abstract

The invention belongs to the related technical field of a parking space positioning method and application thereof, and aims to provide a parking space positioning method based on wheel speed distance measurement and application thereof, the parking space positioning method based on wheel speed distance measurement comprises three steps of wheel speed measurement, parking space calibration and operation, and rapid, accurate and low-cost positioning of a parking space without a GPS signal is realized; in application, the wheel speed distance measurement principle is adopted, auxiliary positioning is carried out on the driving equipment, the problems encountered by RTK differential equipment positioning are solved, and it is guaranteed that the driving equipment can be normally used under various extreme conditions. The method has the advantages of being accurate in positioning, high in reliability, convenient to operate and use, low in investment and application cost and the like, and can be widely applied to the technical field of intelligent parking of urban traffic.

Description

Technical Field

[0001] This invention relates to the technical field of parking space positioning methods and their applications, and particularly to a parking space positioning method based on wheel speed distance measurement and its application. Background Technology

[0002] In recent years, with the continuous increase in urban car ownership, smart parking has become an important part of smart city construction. Making full use of on-street parking is a crucial component of achieving smart parking. Another important aspect of smart parking is parking fee collection. Fee collection facilitates better urban traffic management, and paid parking spaces also simplify daily management and maintenance. The video patrol vehicle system uses geomagnetic sensors and license plate recognition technology to achieve automatic fee collection. The geomagnetic device records the time vehicles enter and exit parking spaces, calculating the duration of their stay. The patrol vehicle automatically identifies license plate numbers of vehicles on the roadside and uses differential GPS technology or an inertial navigation system to determine the parking location of motor vehicles, uploading the license plate number, license plate image, and parking space information to the management platform as the basis for fee collection.

[0003] Currently, video patrol vehicles are generally equipped with RTK differential devices based on satellite navigation systems for vehicle positioning. Centimeter-level high-precision positioning can be achieved through Global Navigation Satellite System (GNSS) + Real-Time Kinematic (RTK) technology. For example, patent application number "CN20181090267.1" discloses an RFID-based parking space car parking status detection system and method. This patent utilizes RFID signal transmission and identification technology, taking advantage of the characteristic of cars shielding RFID signals, to detect shielded RFID tags on the parking space. By combining all shielded RFID tags and their positions, the occlusion contour of the parking space is obtained, enabling real-time detection of the car parking status without human intervention; the detection process is fast and accurate. For example, patent application number "CN20111040066.0" discloses a no-waiting parking management system based on RFID and sensors, including vehicle identification RFID, vehicle detection sensors, and a back-end server. The vehicle detection sensors are connected to the back-end server via wired or wireless communication networks; the vehicle identification RFID and the vehicle detection sensors are connected via an RFID wireless communication protocol; and the vehicle detection sensors and the back-end server are connected via wired or wireless networks, enabling automatic payment without manual operation. Another example is patent application number "CN202310147585.9," which introduces a method and system for correcting positioning deviations of on-street inspection vehicles. The inspection vehicle is equipped with an RFID reader, and RFID electronic tags are installed in the parking spaces. The RFID signals read by the RFID reader are used to calculate the real-time location information of the inspection vehicle; combined with the pre-collected coordinate information from the RFID, deviation information is calculated. When the deviation information exceeds a preset value, the real-time location information of the inspection vehicle is corrected. This can calibrate the errors of high-precision positioning equipment, enabling intelligent inspection vehicles to be applied to more complex road sections and improving inspection accuracy.

[0004] However, in practice, the RTK differential positioning system has been found to have significant drawbacks: First, on narrow urban roads, tall buildings or dense vegetation on both sides of the road can prevent the receiver from receiving a good signal; second, in severe weather conditions such as strong winds, heavy rain, or lightning, the RTK system may lack a fixed solution; third, when patrol vehicles travel at excessive speeds, positioning inaccuracies may also occur. Since parking fee calculations and other applications rely on accurate parking space positioning, existing parking space positioning methods require further improvement. Summary of the Invention

[0005] The main objective of this invention is to provide a parking space positioning method based on wheel speed distance measurement and its application, which features accurate positioning, high reliability, convenient operation, and low application cost. This method utilizes the principle of wheel speed distance measurement to accurately locate fixed parking spaces outdoors or indoors through wheel speed measurement, displacement calibration, and data recording and reading. This solves the problems encountered in RTK differential positioning devices, ensuring accurate parking space information can be obtained under various extreme conditions. Therefore, this parking space positioning method can be used to promote practical applications such as video patrol vehicle toll collection.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a parking space positioning method based on wheel speed measurement, comprising three steps: wheel speed measurement, parking space calibration, and operation. S1: The wheel speed measurement refers to measuring the wheel speed of the traveling device. Specifically, the distance between two points A and B is first determined. The traveling device travels m meters from A to B. The number of pulses transmitted is recorded n by the wheel speed sensor, thereby obtaining the distance traveled by a single pulse as m / n meters. S2: The parking space calibration refers to first obtaining RTK satellite positioning at the starting point, or pre-burying electronic tags at the starting point (2); The parking space calibration is that the driving equipment is equipped with an electronic tag reader and an RTK signal receiver. When the driving equipment passes the starting point, it starts to calibrate the distance. When it travels to the middle position of each parking space, it records the parking space number. At the same time, it calculates the distance traveled by emitting N pulse signals through the wheel speed sensor, and calibrates the parking space position by the distance. Then it travels to the next parking space and calibrates the parking space in the same way. S3: Once all parking spaces are marked, the system records the location information of the corresponding parking spaces. The operation refers to the driving equipment starting from the pre-embedded electronic tag base point, the distance being zeroed, the driving equipment recording the travel distance through the wheel speed sensor, and accurately obtaining the corresponding parking space information, thereby realizing the application and promotion of parking space information.

[0007] Preferably, the wheel speed measurement method is based on a magnetoelectric or Hall effect wheel speed sensor. For a magnetoelectric sensor, the change in the magnetic field near the sensor when the wheel rotates causes the coil to generate an alternating voltage signal. For a Hall effect sensor, the magnetic field changes as the wheel rotates, and the output of a square wave signal is the result of the change in the magnetic field. By measuring the time interval T between two adjacent pulse signals, the wheel speed v = TC can be calculated. If the number of pulse signals recorded within a certain time t is n, then the travel distance S = vt = TnC. The wheel speed measurement method is used to assist in the positioning of the driving equipment, solving the positioning problems encountered by RTK differential equipment and ensuring that the driving equipment can be used normally under various extreme conditions.

[0008] Preferably, the driving device is a video inspection vehicle, which is a two-wheeled, three-wheeled, or four-wheeled electric vehicle, and the video inspection vehicle is either manually driven or automatically driven.

[0009] Preferably, the driving device is equipped with a wheel speed sensor before actual operation, and the distance corresponding to each pulse is obtained by measuring the wheel speed through the wheel speed sensor.

[0010] Preferably, the electronic tag is one of RFID tags or other identifiable and readable NFC tags, UWB tags, and infrared tags.

[0011] Preferably, the electronic tag is set as a base point at the front of the parking space, and one or more are set side by side to avoid affecting information reading if one of them is damaged.

[0012] This invention also discloses an application of a parking space positioning method based on wheel speed distance measurement. This method is applied to a video inspection vehicle to collect vehicle information in parking spaces. The application process specifically includes: (1) If the satellite signal is good at the starting point, the RTK device has a fixed solution; when the video inspection vehicle starts from the starting point, it uses the wheel speed distance measurement method to measure the distance L1 between the starting point and parking space A1, the distance L2 between the starting point and parking space A2, ..., the distance L5 between the starting point and parking space A5. Based on these distances, the current position of the video inspection vehicle can be determined; (2) If the satellite signal is very poor at the starting point, the RTK device cannot work; then an electronic tag is buried at the starting point, which can be a small RFID card. Through the electronic tag reading module mounted on the video inspection vehicle, when the inspection vehicle passes by, the information in the RFID card can be read to determine the position of the parking space corresponding to the current inspection vehicle.

[0013] Compared with the prior art, the present invention has the following beneficial effects: In this invention, wheel speed sensors are used to measure the wheel speed of a vehicle (such as an electric bicycle), and the displacement corresponding to a single pulse is accurately calculated. This method is convenient, fast, and low-cost, and is applicable to different vehicles. In this invention, electronic tags are pre-embedded at any position in front of, in the middle of, or behind the parking space. The starting position is located by an electronic tag reader on the driving equipment and reset to zero. The driving equipment can accurately calculate the driving distance using its built-in magnetoelectric or Hall-effect wheel speed sensors. The parking space position is calibrated by the driving displacement. After the parking space position is calibrated, the data is recorded and used as a reference for the operation data, making it more accurate and error-free. This parking space calibration method can be applied to various fields of parking space positioning, including video inspection vehicles and other vehicles. This method can be used to achieve the positioning of parking spaces whenever necessary. In this invention, the calibrated parking space location information can effectively solve the problem of auxiliary positioning for video inspection vehicles in road environments with poor or no satellite signals, solve the problems encountered in RTK differential equipment positioning, and ensure that the inspection vehicle can be used normally under various extreme conditions. It does not require expensive lidar or high-precision IMU, effectively reducing the equipment investment cost of the inspection vehicle. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the wheel speed measuring structure of the present invention; Figure 2 This is a schematic diagram of the parking space marking structure of the present invention; Figure 3 This is a structural schematic diagram of the video inspection vehicle application according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the overall operation of the video inspection vehicle according to an embodiment of the present invention.

[0015] In the picture: 1. Driving equipment; 2. Electronic tag. Detailed Implementation

[0016] The technical solution of the present invention will be further described in detail below through specific embodiments and in conjunction with the accompanying drawings: Figures 1-2 As shown, a parking space positioning method based on wheel speed distance measurement includes three steps: wheel speed measurement, parking space calibration, and operation. S1: The wheel speed measurement refers to measuring the wheel speed of the traveling device. Specifically, the distance between two points A and B is first determined. The traveling device 1 travels m meters from A to B. The number of pulses transmitted is recorded n by the wheel speed sensor, thereby obtaining the distance traveled by a single pulse as m / n meters. S2: The parking space calibration refers to first obtaining RTK satellite positioning at the starting point, or pre-burying electronic tags 2 at the starting point; the parking space calibration is carried out on the driving equipment equipped with an electronic tag reader and an RTK signal receiver. When the driving equipment passes the starting point, it starts calibrating the distance. When it travels to the middle position of each parking space, it records the parking space number. At the same time, it calculates the distance traveled by emitting N pulse signals through the wheel speed sensor, which is S=N*m / n meters. The position of the parking space is calibrated by the distance. Then it travels to the next parking space and calibrates the parking space in the same way. S3: Once all parking spaces are marked, the system records the parking space location information corresponding to the distance. The operation refers to the driving device 1 starting from the pre-embedded electronic tag 2 base point, the distance being zeroed, the driving device 1 recording the travel distance through the wheel speed sensor, and accurately obtaining the corresponding parking space information, thereby realizing the application and promotion of parking space information.

[0017] Furthermore, the wheel speed measurement method is based on a magnetoelectric or Hall effect wheel speed sensor. For a magnetoelectric sensor, the change in the magnetic field near the sensor when the wheel rotates causes the coil to generate an alternating voltage signal. For a Hall effect sensor, the magnetic field changes as the wheel rotates, and a square wave signal is output. By measuring the time interval T between two adjacent pulse signals, the wheel speed v = TC can be calculated. If the number of pulse signals recorded within a certain time t is n, then the travel distance S = vt = TnC. By measuring the wheel speed, the driving equipment is positioned in an auxiliary manner, solving the positioning problems encountered by RTK differential equipment and ensuring that the driving equipment can be used normally under various extreme conditions.

[0018] Furthermore, the driving device 1 is a video inspection vehicle, which is a two-wheeled, three-wheeled, or four-wheeled electric vehicle, and the video inspection vehicle is either manually driven or automatically driven.

[0019] Furthermore, before the actual operation of the driving device 1, a wheel speed sensor is installed, and the distance corresponding to each pulse is obtained by measuring the wheel speed through the wheel speed sensor; specifically, by measuring the wheel speed, the wheel speed of vehicles of the same or different models can be measured, correcting the factory error of the driving device and ensuring the accuracy of the subsequent distance measurement data.

[0020] Furthermore, the electronic tag 2 is an RFID tag or another identifiable and readable NFC tag, UWB tag, and infrared tag; preferably an RFID tag; specifically, the electronic tag 2 is set as a base point at the front of the parking space, and one or more are set side by side to avoid the information reading not being affected if one of them is damaged.

[0021] An application of a parking space location method based on wheel speed ranging, this method is applied to a video inspection vehicle to collect vehicle information in parking spaces, such as... Figure 3 As shown, the application process specifically includes: (1) If the satellite signal is good at the starting point, the RTK device has a fixed solution; when the video inspection vehicle starts from the starting point, it uses the wheel speed distance measurement method to measure the distance L1 between the starting point and parking space A1, the distance L2 between the starting point and parking space A2, ..., the distance L5 between the starting point and parking space A5. Based on these distances, the current position of the video inspection vehicle can be determined; (2) If the satellite signal is very poor at the starting point, the RTK device cannot work; then an electronic tag is buried at the starting point, which can be a small RFID card. Through the electronic tag reading module mounted on the video inspection vehicle, when the inspection vehicle passes by, the information in the RFID card can be read to determine the current position of the inspection vehicle.

[0022] Example 1: S1: Prepare a driving device 1, which is a two-wheeled electric bicycle, driven by a person and equipped with a Hall-type wheel speed sensor. First, measure the wheel speed of the driving device. Specifically, first locate the distance between two points A and B. The driving device 1 travels 1000 meters from A to B. The wheel speed sensor records 50,000 pulses, thus obtaining the distance traveled by a single pulse as 0.02 meters. S2: Two electronic tags 2 are pre-embedded side by side in front of the parking space. The driving device 1 is equipped with an electronic tag reader. When the driving device 1 passes the electronic tag 2, it starts to calibrate the distance. The distance data is cleared to zero. When it moves to the middle position of the first parking space, the parking space number is recorded. At the same time, the number of pulse signals emitted by the wheel speed sensor is 300 to calculate the distance traveled S = 300 * 0.02 meters = 6 meters. Thus, it can be known that after traveling 6 meters, it is the first parking space and the position of the parking space is marked. When it moves to the middle position of the next parking space, there are 220 pulses. Thus, the distance of the second parking space is S = 220 * 0.02 meters = 4.4 meters. And so on, the distance is calibrated for all parking spaces. S3: After all parking spaces are calibrated, the driving device 1 starts from the pre-embedded electronic tag 2 base point, the distance is automatically reset to zero, the driving device 1 records the travel distance through the wheel speed sensor, and accurately obtains the corresponding parking space information.

[0023] Example 2: S1: Prepare a driving device 1, which is a four-wheeled electric bicycle, driven by a person and equipped with a magnetoelectric wheel speed sensor. First, measure the wheel speed of the driving device. Specifically, first locate the distance between two points A and B. The driving device 1 travels 1000 meters from A to B. The wheel speed sensor records 40,000 pulses, thus obtaining the distance traveled by a single pulse as 0.025 meters. S2: An electronic tag 2 is pre-embedded at the dividing point between parking spaces. The driving device 1 is equipped with an electronic tag reader. When the driving device 1 passes the electronic tag 2, it starts to calibrate the distance. The distance data is cleared to zero. It moves forward to the middle position of the Nth parking space and records the parking space number. At the same time, the wheel speed sensor emits 100 pulse signals to calculate the distance traveled, S = 100 * 0.025 meters = 2.5 meters. Thus, after traveling 2.5 meters, it is the Nth parking space, and the position of the parking space is marked. When it moves to the middle position of the next parking space, there are 200 pulses. Thus, the distance to the (N+1)th parking space is S = 200 * 0.025 meters = 5 meters. However, if it travels in the opposite direction, it will be recorded as a negative number. Starting from the base point of the electronic tag 2, the distance traveled to the (N-1)th parking space number is S = -100 * 0.025 = -2.5 meters. And so on, the distance is calibrated for all parking spaces. S3: After all parking spaces are calibrated, the driving device 1 starts from the pre-embedded electronic tag 2 base point, the distance is automatically reset to zero, the driving device 1 records the travel distance through the wheel speed sensor, and accurately obtains the corresponding parking space information.

[0024] Example 3: S1: Prepare a driving device 1, which is a two-wheeled electric bicycle used for video inspection. It is a type of video inspection vehicle, driven manually and equipped with a Hall-type wheel speed sensor. It is also equipped with a video acquisition module, a visual information processing module, and an electronic tag reading module. All modules are integrated in the trunk of the driving device. First, measure the wheel speed of the driving device 1. Specifically, first locate the distance between two points A and B. The driving device 1 travels 1000 meters from A to B. The wheel speed sensor records 100,000 pulses, thus obtaining the distance traveled by a single pulse as 0.01 meters. S2: Two electronic tags 2 are pre-embedded side by side behind the parking space. The driving device 1 is equipped with an electronic tag reader. When the driving device 1 passes the electronic tag 2, it starts to calibrate the distance. The distance data is cleared to zero. When it moves to the middle position of the first parking space, the parking space number is recorded. At the same time, the number of pulse signals emitted by the wheel speed sensor is 350 to calculate the distance traveled S = 350 * 0.01 meters = 3.5 meters. It can be seen that after traveling 3.5 meters, it is the last parking space N, and the position of the parking space is marked. When it moves to the middle position of the next parking space, there are 400 pulses. It can be seen that the distance of the second to last parking space N-1 is S = 400 * 0.01 meters = 4 meters. And so on, the distance is calibrated for all parking spaces. S3: After all parking spaces are calibrated, the driving device 1 starts from the pre-embedded electronic tag 2 base point, automatically zeroing the distance. The driving device 1 records the travel distance through wheel speed sensors and accurately obtains the corresponding parking space information. When the satellite signal at the starting point is good, the RTK device has a fixed solution. When the driving device 1 starts from the starting point, it uses wheel speed distance measurement to measure the distance L1 between the starting point and parking space A1, the distance L2 between the starting point and parking space A2, ..., the distance L5 between the starting point and parking space A5. Based on these distances, the current position of the video inspection vehicle can be determined. When the satellite signal at the starting point is poor, the RTK device cannot work. The electronic tag reading module on the driving device 1 is used to determine the current position of the inspection vehicle. The specific operation is as follows: Figure 4 As shown; S4: The video acquisition module captures image data through the camera component and transmits the acquired image data to the visual information processing module, which includes a license plate recognition module and a parking space recognition module. S5: The visual information processing module, in conjunction with the differential GPS / inertial navigation module, locates the current position of the inspection vehicle and simultaneously identifies vehicle license plate information and vehicle parking space information; S6: After obtaining the relevant location information, the backend software performs calculations such as parking space statistics and parking fee calculations, enabling smart parking fee collection for personal terminals, such as... Figure 4 As shown, the location of the driving device 1 (video inspection vehicle) is first located by Beidou / GPS signal 3 and electronic tag 3, thereby recording the vehicles and parking time in parking space 5. The built-in device of the video inspection vehicle sends the relevant information to the back-end terminal 4. The back-end terminal 4 generates license plate and payment or violation information and sends the information to the vehicle owner 6, forming a closed-loop workflow.

[0025] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A parking space positioning method based on wheel speed distance measurement, characterized in that, It includes three steps: wheel speed measurement, parking space calibration, and operation. S1: The wheel speed measurement refers to the measurement of the wheel speed of the driving equipment (1); S2: The parking space calibration refers to first obtaining RTK satellite positioning at the starting point, or pre-burying electronic tags at the starting point (2); S3: After all parking spaces are marked, the system records the parking space location information corresponding to the distance. The operation refers to the driving device (1) starting from the base point, the distance is returned to zero, the driving device (1) records the travel distance through the wheel speed sensor, and accurately obtains the corresponding parking space information.

2. The parking space positioning method based on wheel speed distance measurement according to claim 1, characterized in that: The wheel speed determination in step S1 is specifically as follows: first, locate the distance between points A and B, and then the driving device (1) travels m meters from A to B. The number of pulses transmitted is recorded n by the wheel speed sensor, thereby obtaining the distance traveled by a single pulse as m / n meters.

3. The parking space positioning method based on wheel speed distance measurement according to claim 1, characterized in that: The driving device (1) is equipped with an electronic tag reader and an RTK signal receiver. When the driving device passes the starting point, it starts to calibrate the distance. When it travels to the middle position of each parking space, it records the parking space number. At the same time, it calculates the distance traveled by emitting N pulse signals through the wheel speed sensor, which is S=N*m / n meters. The parking space position is calibrated by the distance. Then it travels to the next parking space and calibrates the parking space in the same way.

4. The parking space positioning method based on wheel speed distance measurement according to claim 1, characterized in that: The wheel speed measurement is based on a magnetoelectric or Hall effect wheel speed sensor. For a magnetoelectric sensor, the change in the magnetic field near the sensor when the wheel rotates causes the coil to generate an alternating voltage signal. For a Hall effect sensor, the magnetic field changes as the wheel rotates, and the output of a square wave signal is the result of the change in the magnetic field. By measuring the time interval T between two adjacent pulse signals, the wheel speed v = TC can be calculated. If the number of pulse signals recorded within a certain time t is n, then the travel distance S = vt = TnC. The wheel speed measurement is used to assist in the positioning of the driving equipment, solving the positioning problems encountered by RTK differential equipment and ensuring that the driving equipment can be used normally under various extreme conditions.

5. The parking space positioning method based on wheel speed distance measurement according to claim 1, characterized in that: The driving device (1) is a video inspection vehicle, which is a two-wheeled, three-wheeled or four-wheeled electric vehicle, and the video inspection vehicle is driven manually or automatically.

6. The parking space positioning method based on wheel speed distance measurement according to claim 5, characterized in that: Before actual operation, the driving device (1) is equipped with a wheel speed sensor, and the distance corresponding to each pulse is obtained by measuring the wheel speed through the wheel speed sensor.

7. The parking space positioning method based on wheel speed distance measurement according to claim 1, characterized in that: The electronic tag (2) is one of the following: RFID tag or other identifiable and readable NFC tag, UWB tag and infrared tag.

8. The parking space positioning method based on wheel speed distance measurement according to claim 7, characterized in that: The electronic tag (2) is set as a base point at the front of the parking space, and one or more are set side by side to avoid the information reading not being affected when one of them is damaged.

9. An application of a parking space positioning method based on wheel speed distance measurement, wherein the method is applied to a video inspection vehicle to collect vehicle information in parking spaces, characterized in that... The application process specifically includes: (1) If the satellite signal is good at the starting point, the RTK device has a fixed solution; when the video inspection vehicle starts from the starting point, it uses the wheel speed distance measurement method to measure the distance L1 between the starting point and parking space A1, the distance L2 between the starting point and parking space A2, ..., the distance L5 between the starting point and parking space A5. Based on these distances, the current position of the video inspection vehicle can be determined; (2) If the satellite signal is very poor at the starting point, the RTK device cannot work; then an electronic tag is buried at the starting point, which can be a small RFID card. Through the electronic tag reading module mounted on the video inspection vehicle, when the inspection vehicle passes by, the information in the RFID card can be read to determine the position of the current inspection vehicle corresponding to the parking space.

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