WO2021230825A1

WO2021230825A1 - Method for detection of presence of a motor vehicle in a monitored zone with identification of its engine type and detection device

Info

Publication number: WO2021230825A1
Application number: PCT/SK2021/050005
Authority: WO
Inventors: Ondrej Závodský; Ľubomír Pasternák; Alexander Kutka; Pavol Turčina
Original assignee: GOSPACE Tech s. r. o.
Priority date: 2020-05-11
Filing date: 2021-05-10
Publication date: 2021-11-18
Also published as: SK500252020A3

Abstract

The method of detection of the presence of the motor vehicle in the monitored zone with identification of its engine type includes the steps: - activation of the magnetic field sensor by control unit to detect a change in the surrounding magnetic field; - after detection of a change in the surrounding magnetic field, the radar sensor is activated by control unit to detect the presence of the motor vehicle in the monitored zone and the activation of the acoustic sensor by control unit to identify the engine type of the motor vehicle in the monitored zone; - evaluation of data sensed by computing unit from the magnetic field sensor, radar sensor and acoustic sensor to provide information on presence of the motor vehicle and the type of engine of the motor vehicle in the monitored zone; - sending the information data by communication unit via the data network into the data storage. The detection device for detection of presence of the motor vehicle in the monitored zone with identification of its engine type consists of the control and computing unit to which they are connected. - the sensing unit comprising the magnetic field sensor, the radar sensor and the acoustic sensor; - communication unit with antennas; - source of electricity.

Description

Method for detection of presence of a motor vehicle in a monitored zone with identification of its engine type and detection device

Technical field

The invention relates to a method for detection of presence of a motor vehicle present in a monitored zone, i. e. motor vehicle parked above a detection device and also relates to the identification of the just identified motor vehicle with a running engine being any type of: diesel, gasoline, CNG, electricity. The invention also relates to the detection device itself (hereinafter also referred to as the detection device). The invention belongs to the field of the automotive industry and the field of smart cities.

Background of the invention

The number of cars in cities is increasing. On the other hand, the number of parking spaces in the streets and city zones remains approximately the same, respectively increases only to a limited extent. As a result, almost all cities have a problem with parking.

However, currently used solutions have many limitations. Magnetometry-based detectors often struggle with inaccurate measurements, poor battery life, and do not allow software updates or status recordings during possible network outages. The existing solutions usually rely on proprietary protocols and require the deployment of gateways, which is not cost-optimal. Alternatively, the detection of presence of the parked cars may be based on cameras mounted only on buildings or lamps, they need to be powered and connected to the Internet, so that areas outside such infrastructures cannot be monitored by cameras. In addition, changing weather conditions, such as rain, fog, or snow, reduce the accuracy of camera-based sensing detection. Effective and reliable parking monitoring and management solutions must be built on accurate, high-quality and cost-optimal detection technology, with sophisticated data analysis and easy maintenance. For this reason, there is a clear market demand for a highly efficient and accurate intelligent parking solution based on loT (Internet of Things) sensors running on the existing long-lasting infrastructure, with long battery life and almost 100% detection accuracy and additional authentication function (to extend usability) and compatibility with major loT networks for large-scale global deployments. Several wireless parking sensors are currently well known. Wireless magnetic parking sensors are designed to detect the availability of a parking space, responding to changes in the magnetic field when the vehicle is parked above them. They also transmit real-time parking space availability information to the monitoring system. These parking sensors are realized in the shape of a flat disk and are installed on the surface of the parking space or are installed below the surface of the parking space as is known from the Slovak utility application no. 8499, in which the parking sensor contains only a magnetometer.

The solution described in document U.S. Pat. No. 10,525,845 B2 is known in the prior art, where the following is determined at the charging station of electric vehicle by means of a range detection sensor with integrated RADAR, LIDAR sensor, ultrasonic and infrared sensor: vehicle type characteristics (standard, electric, hybrid, etc.); identification information (VIN, license plate, etc.) and battery status information. The charging station responds on basis of the specified characteristics and informs about the unreasoning occupation of the charging point.

The low-energy parking sensor described in document US 10,297,150 B2, with magnetometer, optical, pressure and ultrasonic sensor, monitors the occupancy of the parking space, where the main criterion is the parking time.

Among the current requirements for parking, the ban on entering motor vehicles with diesel engines in the designated urban zones is coming to the fore. This problem has put pressure on the development of parking sensor designs that would primarily identify diesel vehicles. The efforts of the originators led to the creation of intelligent parking or so-called "smart parking" in effort to optimize the current state by means of detection of presence of the motor vehicle present in the monitored zone, i. e. of the motor vehicle parked above the detection device and identification of the just identified motor vehicle with the running engine from type of the driven unit: diesel, gasoline, CNG, electricity according to this invention. Summary of the invention

The above introduced technologies are limited to detection of presence of the motor vehicle and do not include other functionalities for identifying the type of motor vehicle, according to mass or energy burned. This disadvantage is eliminated by the method for detecting of presence of the motor vehicle in the monitored zone with identification of its engine type and the detection device according to the invention, the method essence of which consists in that the sensing unit contains the sensing components, which sense analogue parameters of surrounding ambient of the detection device and consequently these parameters are digitized and read by the control unit. In the first step, the control unit activates the magnetic field sensor to detect a change in the surrounding magnetic field. The magnetic field sensor is activated max. 2 seconds and then min. 2 seconds, where at given intervals it measures the level of the surrounding magnetic field in three axes. The sensed values of the magnetic field are evaluated in the control and computing unit, where the size of the magnetic field vector is calculated according to formula:

If the size of the Btot vector exceeds the defined value during n consecutive measurements, the detection algorithm proceeds in the second step in the measurement by means of the radar sensor (micro-radar) and acoustic sensor. Radar sensor and acoustic sensor are activated max. 2 seconds. The radar sensor measures the amplitude of reflection of the electromagnetic signal in time. The acoustic sensor samples the sound waves generated by vehicle engine during this time.

The control unit preferably monitors the operating conditions of the detection device by means of a temperature sensor, and subsequently the computing unit evaluates possible thermal anomalies which could affect the accuracy of the measured data and the service life of the detection device. The temperature sensor is preferably activated at regular intervals.

In the next process step, the calculation unit modifies the sensed values, using calibration tables. The proposed mathematical algorithms and artificially intelligent evaluation methods based on neural networks are then applied to the values adjusted in this way, in order to correctly identify the presence of the vehicle and the engine type of the currently identified vehicle. After the computing unit evaluates presence of the motor vehicle, the control and computing unit preferably turns on the short-distance two-way communication process (Bluetooth, BLE and Ultrawideband, UWB) in order to identify the user of the currently parked vehicle. This process preferably includes applications such as authorized parking identification, parking time monitoring for automatic payment, motor vehicle type identification via BLE, or communication with other devices such as external signaling, gate opening, reporting on vehicle presence for dispatching and so on.

When using BLE, only the presence of a vehicle nearby the detection device can be determined. In order to determine a more precise location of a vehicle, UWB is preferably used. This is advantageous in order determine the exact vehicle ID when there are more vehicles, that are BLE visible, parking nearby the detection device, so incorrect identifications are possibly avoided. Proximity (e.g. distance) measurement with vehicle is triggered only by a BLE/UWB enabled identifier. Such a proximity measurement is using unique identification numbers assigned to the detection device during manufacturing and to the identifier during its association with an user or a vehicle.

The UWB proximity measurement of the UWB identifier is triggered only when the UWB identifier is actively scanned (BLE Active Scanning) by the detection device. UWB identifier recognizes the identity of the detection device based on the MAC address transferred in the scan request packet, SCAN_REQ from the detection device to the UWB identifier. After identity of the detection device is recognized and validated the UWB identifier sends UWB poll frame addressed to the scanning detection device. Two Way Ranging communication (TWR) protocol is used i.e. three UWB frames are transferred (poll, response, final) between the UWB modules of the UWB identifier and the detection device in order to measure the distance. Consistency of the communication is achieved by tokenizing it so unsolicited frames coming to UWB radio (from different UWB identifiers or detection devices) are dropped and the whole process can be timed out, rejected, or repeated in case of a problem or mismatch.

The UWB proximity (distance measurement) is done within at most 20 ms. The latency between the moment the UWB distance measurement is triggered (UWB detector sends SCAN_REQ via BLE to UWB identifier) and the time when UWB detector receives first frame from UWB identifier, the POLL frame, is at most 6 s. The remaining at most 14 s are dedicated to the rest of the UWB TWR communication. The described process of UWB triggering (activation) is designed with the consideration of the device being low powered. It is commonly known the UWB communication consumes to much electric energy to process, so it is advantageous if activated for as short time as possible and the described UWB triggering and proximity measurement process leads to best results.

Preferably, the repeated UWB proximity (distance measurement) is rejected by the UWB identifier until a defined timeout runs out, so additional energy savings can be achieved. This measurement repetition per session is preferably blocked until consecutive SCAN_REQ (scan requests) are coming from the very same detection device, which was subject to the previous TWR communication. In case of the SCAN_REQ are missing during the defined timeout then UWB measurement is unblocked to be repeated with the same detection device in next scanning session.

In the third main process step, data on presence and type of the motor vehicle are evaluated, alongside with data about the user of the vehicle exposed to the communication unit. Each communication unit is connected to its own radio antenna, for sending and receiving radio waves. Subsequently, after the communication unit receives the result data packet and the command to send it from the control unit, the communication unit establishes the connection with data network via antenna and sends the data. Any communication with the data storage via the data network is subjected to strict security rules.

A method for detection of presence of the motor vehicle in the monitored zone with identification of its engine type is performed on the detection device according to the invention, the essence of the method being that the detection device for detection of the motor vehicle and its identification comprises the sensor unit that converts analogue signals to digital. The device comprises the control unit which controls and manages the whole device, as well as the computing unit for processing, evaluation and mathematical instructions applied to the sensed data. Preferably, the control unit and the computing unit are arranged as the common control and computing unit. This is understood that the entire invention described herein may equally well be implemented by the common control and computing unit or the separate control and computing units. Furthermore, the device also contains the communication unit together with the necessary antenna system as well as the internal monitored power supply. In terms of mechanical construction, the respective detection device is resistant to the external environment, it is hermetically sealed in a housing and meets the requirements for ambient covering protection IP68. Stiffness and mechanical strength requirements resistant to the pressure generated by weight of the motor vehicles are also taken into account.

From the point of view of electrical supply, the detection device preferably comprises its own battery, capable of providing of the power source for all peripherals of the motor vehicle detector, for more than five years, during normal parking cycles (20 parked vehicles / day). The internal power supply preferably includes monitoring of its own energy backup, the course of consumption during the entire life of the device, evaluation of possible anomalies and prediction of the life of the device.

Software of the detection device contains functions for control of the sequence of processes for operating individual units (sensor unit, communication unit and power supply unit) as well as separate algorithms for evaluation of the sensed values and artificial intelligence supporting decision-making in determining of engine type of the sensed motor vehicles

The sensor unit preferably consists of system of the sensors for measuring non electrical quantities such as the magnetic field sensor - magnetometer, radar sensor - micro-radar, acoustic sensor and temperature sensor. The sensor unit preferably uses a high-precision 3-axis magnetometer to measure the intensity of the magnetic field in the X, Y, Z axes in its vicinity. A change in the intensity of the magnetic field indicates the possible presence of the motor vehicle, which by its metal construction changes the magnetic field in its immediate vicinity. The integrated radar sensor with its own antenna detects the presence of the vehicle by measuring the time and intensity of the reflected electromagnetic signal from the vehicle chassis. The radar sensor also measures non-contact vibrations of the motor vehicle. The radar sensor is preferably the pulsed coherent radar sensor calibrated to detect reflection waves in the range of 10 cm to 70 cm and is preferably located on top of the printed circuit board below the micro-radar lens. The acoustic sensor preferably senses acoustic waves in the band from 10 Hz to 20 kHz generated by the motor vehicle, standing above the sensing unit of the detection device. The detection device of the motor vehicle also consists of the communication unit, which consists of communication modules and the system of radio antennas, for transmitting and receiving radio signals. Preferably, it comprises at least one transmitter and at least one radio wave receiver in the range band:

• 3.1 GHz to 4.8 GHz mainly, but not exclusively for short distance communication with UWB identification devices;

• 2.4 GHz mainly, but not exclusively for short distance communication with BLE identification devices;

• Frequency LTE (Long Term Evolution) bands B8 and B20 for Europe

• Frequency LTE bands B2, B4 and B12 for the USA

It is also possible to use other technology suitable for the transmission of information.

The communication module preferably uses one of the following available loT technologies:

- LoRa (Long Range), for sending and receiving signals over long distances with LoRa stations

- SigFox, for sending and receiving signals over long distances with SigFox stations

- NBIoT (Narrow Band Internet of Things) unit for sending and receiving signals over long distances within the LTE network containing sensing unit telemetry, technical status information, vehicle user identification and vehicle identification.

The communication module preferably comprises a Bluetooth unit for two-way communication over short distances comprising vehicle user identification, vehicle identification or communication with a mobile device.

The communication module preferably comprises a UWB unit for two-way communication over short distances comprising the identification of the vehicle user as well as the distance of the UWB identifier from the sensing unit or communication with a mobile device.

The communication unit preferably comprises the system of radio antennas for operating the radio signal, for each of the above-mentioned communication modules. The antennas are designed and adapted to the requirements of the device and can form part of a printed circuit board. The detection device may comprise analogue signaling, preferably consisting of LED lamp for visual signaling of defined sensor states. The analogue signaling may also include a buzzer for audible signaling of defined sensor states.

The detection device of the motor vehicle comprises the control and computing unit, which preferably consists of the single-chip micro-controller, serving for the administration and control of the whole device, operation of the individual internal communication lines with the peripherals of the device. The control and computing unit is used for acquisition, processing, analysis and evaluation of sensed data. The control unit also serves to encrypt and display the evaluated data, as well as data on the technical condition of the detection device. The control and computing unit is also used to manage the energy flow of the entire system, optimize consumption through the management of active peripherals and optimize computing processes.

The advantages of the method of detection of presence of the motor vehicle in the monitored zone with the identification of its motor type and the detection device according to invention are apparent from its effects, which are manifested externally. The effects and originality of the presented solution lie in the use of a unique intelligent solution for loT parking with a Fleximodo SPOT parking sensor with real-time parking space occupancy evaluation technology. This technology is universal for all types of the Internet of Things (LoRaWAN - Long Range Wide Area Network, SigFox, NB-loT and LTE). The functionality of sensor authentication with a second loT device (eg a card) was also developed, which enables the detection of the right to park or the so- called electronic parking permits. The sensor is equipped with two types of sensors (magnet and micro-radar), and in combination with algorithms on the cloud achieves almost 100% detection success, which is a unique accuracy on the market of similar sensors.

This technology is completed by the unique functionality of distinguishing of the type of motors of parked cars (diesel, gasoline and electric). This functionality can also be used to detect the so-called "engine idling", when the car has the engine running after parking and thus contributes to air pollution. The sensor is also able to compare the noise level around the sensor and alert it to changes over time. Brief description of the drawings

The method of detection of presence of the motor vehicle in the monitored zone with the identification of its engine type and the detection device according to the invention will be shown in the drawings, where in Fig. 1 shows the method of detection and identification by the detection algorithm. In Fig. 2 shows the operating flow of the motor vehicle detector. In Fig. 3 shows the layout of the individual components of the detection device on the printed circuit board. In Fig. 4 shows a partially exposed detection device.

Example of an embodiment

It is understood that the individual embodiments of the invention are presented by way of illustration and not by way of limitation of the technical solutions. Those skilled in the art will find or be able to ascertain using no more than routine experimentation, many equivalents to specific embodiments of the invention. Such equivalents will also fall within the scope of the claims.

For those skilled in the art, an optimal design should not be a problem, so these features have not been addressed in detail.

Example

In this example of the specific embodiment of subject of the invention, the detection device for detection of presence of the motor vehicle in the monitored zone with identification of its engine type is described, as shown in Fig. 2 to 4. The detection device comprises a printed circuit board 1 , which is connected to a high-capacity industrial battery 18, which serves as the main power supply of the whole device. The printed circuit board 1 comprises a voltage source regulator 13 for regulation and control of the required voltage levels for each device module. The printed circuit board 1 comprises a micro-controller 9 (control and computing unit) with its own internal memory, connected to a voltage source. The printed circuit board 1 comprises a magnetic field sensor 7 connected to the micro-controller 9. The printed circuit board 1 comprises an integrated radar sensor 12 with its own antenna 15 connected to the micro-controller 9. The radar sensor 12 is a pulsed coherent radar sensor calibrated to detect reflection waves in an interval of 10 cm to 70 cm and is located on the upper side of the printed circuit board 1 below the micro-radar lens 19. The printed circuit board 1 comprises a thermal sensor connected to micro-controller 9. The printed circuit board 1 comprises an acoustic sensor 8 connected to micro-controller 9. The printed circuit board 1 comprises the communication unit 5 connected to micro controller 9. The communication unit 5 with the antennas (15) comprises at least one transmitter and at least one receiver of radio waves in the band from the range:

• 3.1 GHz to 4.8 GHz for short distance communication with UWB identification devices;

• 2.4 GHz for short distance communication with BLE identification devices;

• Frequency LTE bands B8 and B20 for Europe;

• Frequency LTE bands B2, B4 and B12 for USA.

The printed circuit board 1 comprises a communication module LoRa connected to micro-controller 9. The printed circuit board 1 comprises a communication module SigFox connected to the micro-controller. The printed circuit board 1 comprises a communication module NB-loT connected to micro-controller 9. The printed circuit board 1 comprises a Bluetooth communication module 10 connected to micro controller 9. The printed circuit board 1 comprises an UWB communication module connected to the micro-controller 9. The printed circuit board 1 comprises its own system of antennas 15, designed directly on the top layer of the printed circuit board, serving the two-way transmission of radio signals of each of the above-mentioned communication modules. The printed circuit board 1 comprises a LED light signaling 6 connected to the micro-controller 9. The printed circuit board 1 comprises a buzzer 4 for acoustic signaling connected to the micro-controller 9. The printed circuit board 1 contains the set of auxiliary electrical components needed for recovery and proper functionality above of the mentioned electrical components. The printed circuit board 1 , soldered with the above-mentioned electrical components as well as with the auxiliary electrical components and the battery 18, is placed in a hermetically sealed housing 16. All the above-mentioned electrical components are mounted on the upper side of the printed circuit board 1. The battery 18 of the device is attached and soldered to lower side of the printed circuit board 1. The housing 16 of the vehicle detection device comprises a delimiting silent block 17 to achieve the set delimitation between the sensor circuit board 1 and the upper part of the housing 16. The outer part of the housing 16 of the vehicle detection device comprises a micro-radar lens 19 located above the radar sensor 12 antenna serves to reduce the beam width of the electromagnetic signal from 90 degrees to 20 degrees, which improves the sensitivity of vehicle detection. Preferably, the lens is selected to have the circumference 21 .83 mm and a radius of concavity 12 mm and it is arranged so that the distance between the bottom of the lens 19 and the radar 12 is 5 mm with a maximum tolerance 10%. Under these conditions, the sensitivity of the detection is highest.

The detection device for detection of presence of the motor vehicle in the monitored zone with the identification of its engine type operates in a manner which can be seen in Fig. 1 as follows in steps:

- activation of the magnetic field sensor by the control unit to detect a change in the surrounding magnetic field;

- after detection a change in the surrounding magnetic field, the radar sensor is activated by the control unit to detect the presence of the motor vehicle in the monitored zone and the activation of the acoustic sensor by control unit to identify the engine type of the motor vehicle in the monitored zone;

- evaluation, by computing unit, of the sensed data from the magnetic field sensor, the radar sensor and the acoustic sensor to provide information on the presence of the motor vehicle and the type of engine of the motor vehicle in the monitored zone;

- sending information data by communication unit via the data network into the data storage.

Alternatively, a control step is inserted between the step of activation of the magnetic field sensor and the step of activation the radar sensor and the acoustic sensor, in which the operating conditions of the detection device are monitored by means of the temperature sensor. Preferably, the magnetic field sensor is activated for 2 seconds and then deactivated for 2 seconds. The radar sensor is activated for 2 seconds and also the acoustic sensor is activated for max. 2 seconds. The partial activation of the individual sensors leads to reduced power consumption. It has been found that the above introduced combination of time intervals guarantees a long service life of the device in terms of energy efficiency, which is extremely important for long-term maintenance-free use of the parking sensor in real conditions. Industrial applicability

The solution according to invention can be used in parking systems, in parking management in zones with a special regime, but also in other applications where it is necessary to monitor the presence of vehicles in the monitored zones and identify their technical characteristics.

List of related reference number

1 . printed circuit board

2. Sim chip

3. holder of sim card

4. buzzer

5. loT communication module

6. LED light signalling

7. magnetometer

8. acoustic sensor

9. micro-controller (control and computing unit)

10. Bluetooth chip

11 . energy consumption meter

12. radar sensor

13. voltage controller

14. UWB

15. antenna system

16. detection device housing

17. silent-block

18. battery

19. micro-radar lens

Claims

1 . The method for detection of presence of the motor vehicle in the monitored zone, characterized in that it comprises the steps:

- activation of the magnetic field sensor (7) by a control and computing unit (9) to detect a change in the surrounding magnetic field;

- after detection of a change in the surrounding magnetic field, the activation of a radar sensor (12) by the control and computing unit (9) to detect the presence of a motor vehicle in the monitored zone and the activation of an acoustic sensor (8) by the control and computing unit (9) to identify the motor vehicle engine type in the monitored zone;

- evaluation of the sensed data from the magnetic field sensor (7), the radar sensor (12) and the acoustic sensor (8) by the control and computing unit (9) to provide information on presence of the motor vehicle and the motor vehicle engine in the monitored zone;

- sending the information data containing the information on the presence of the motor vehicle and on the engine of the motor vehicle in the monitored zone by communication unit (5) via the data network into a data storage.

2. The method according to claim 1 , characterized in that the information data comprises any information from the following set:

- vehicle identification;

- engine type information;

- vehicle user identification;

- the distance of an UWB identifier from the sensor unit;

- information from telemetry of the sensor unit;

- information on the technical condition of the detection device.

3. Method according to any one of the preceding claims, characterized in that a control step is inserted between the step of activation of the magnetic field sensor (7) and the step of activation of the radar sensor (12) and the acoustic sensor (8), in which the operating conditions of the detection device are monitored by means of the temperature sensor.

4. Method according to any one of the preceding claims, characterized in that the magnetic field sensor (7) is activated for max. 2 seconds and then it is deactivated for min. 2 seconds.

5. Method according to any one of the preceding claims, characterized in that the radar sensor (12) is activated for max. 2 seconds.

6. Method according to any one of the preceding claims, characterized in that the acoustic sensor (8) is activated for max. 2 seconds.

7. Device for detection of presence of the motor vehicle in the monitored zone according to method of at least one of Claims 1 to 6, characterized in that it is formed by control and computing unit (9) to which they are connected:

- sensor unit comprising the magnetic field sensor (7), radar sensor (12) and acoustic sensor (8);

- communication unit (5) with at least one antenna (15);

- power supply unit (18).

8. Device according to claim 7, characterized in that it comprises a micro-radar lens and / or a temperature sensor.

9. Device according to any one of claims 7 to 8, characterized in that the radar sensor (12) is a pulsed coherent radar sensor calibrated for detection of reflection waves in the range 10 cm to 70 cm and / or the acoustic sensor (8) is arranged for detection of acoustic waves with frequency from 10 Hz to 20 kHz.

10. Device according to any one of claims 7 to 9, characterized in that the control and computing unit (9) and the communication unit (5) with at least one antenna (15) and with the sensor unit comprising the magnetic field sensor (7), the radar sensor (12) and the acoustic sensor (8) are mounted in the printed circuit board (1 ), which together with the battery (18) is placed on a silent-block (17) in a housing (16) with a micro-radar lens (19).

11 . Device according to any one of claims 7 to 10, characterized in that the radar sensor (12) is located on the upper side of the printed circuit board (1 ) below the micro radar lens (19).

12. Device according to any one of claims 7 to 11 , characterized in that the communication unit (5) with at least one antenna (15) comprises at least one transmitter and at least one radio wave receiver in the range band:

• 2.4 GHz for short distance communication with BLE identification devices;

• Frequency LTE bands B8 and B20 for Europe;

• Frequency LTE bands B2, B4 and B12 for USA.

13. Device according to Claim 12, characterized in that the communication unit (5) with at least one antenna (15) comprises the integrated Bluetooth signal receiving and transmitting module (10) and / or the integrated UWB receiving and transmitting module (10).

14. Device according to Claim 12 or 13, characterized in that the communication unit (5) with at least one antenna (15) comprises the integrated receiving and transmitting module of the following series: LoRa, NBIoT, SigFox.