Monitoring method and device and intrusion alarm system
Through the intrusion alarm system combined with signal receiving device and space triangular positioning algorithm, the problem of misjudgment of electric bicycles and batteries in elevators is solved, accurate identification and blocking is achieved, safety and scope of application are improved, and energy consumption and cost are reduced. .
Patent Information
- Application Number
- CN202411387039.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-30
- Publication Date
- 2024-12-17
- Estimated Expiration
- 2044-09-30
AI Technical Summary
The prior art recognizes that electric bicycles and their batteries have misjudgments or misjudgments in elevators, and cannot effectively prevent the disassembled electric bicycle batteries from entering the elevator, resulting in fire safety hazards, and the visual identification method is costly and has limited application scope.
The signal receiving device and signal transmitting device are used to cooperate with the spatial triangular positioning algorithm to determine whether the intrusion target is in the monitoring area through the RSSI value of the wireless signal, and are connected to the elevator control system to accurately identify and prevent the intrusion target from entering the elevator.
It realizes accurate identification and blocking of electric bicycles and their batteries, reduces the rate of misjudgment, improves safety and scope of application, and has a simple structure, is not complex in algorithms, and reduces energy consumption and production costs.
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Figure CN119152625A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of intrusion alarms, and in particular to a monitoring method, a device and an intrusion alarm system. Background Art
[0002] At present, there are safety hazards when electric bicycles are used in elevators in residential buildings, commercial buildings and other places. When an electric bicycle or battery is short-circuited or overcharged, it may cause safety accidents such as fire. There are many visual recognition technologies that can identify electric bicycles in the elevator car to prevent them from entering the elevator. However, due to the variety of items carried by elevator passengers and the fact that many passengers are obstructed by visual recognition, there are disadvantages in the way that visual recognition prevents electric bicycles from entering the car. Misjudgments or missed judgments often occur, and visual recognition cannot solve the problem of passengers taking disassembled electric bicycles into the elevator to go upstairs. The part of the electric bicycle that poses a fire hazard is its battery. Therefore, it is of great practical significance to develop a new monitoring method, device and intrusion alarm system that can effectively identify and prevent electric bicycles or disassembled batteries from entering the elevator, and it is also necessary to take into account accuracy and production costs as well as the need to be applicable to more scenarios. Summary of the invention
[0003] To solve the above problems, the present invention provides a monitoring method, device and intrusion alarm system. The signal receiving device cooperates with the signal transmitting device to obtain the RSSI value in real time. The RSSI value can more accurately determine the position distance between the signal transmitting device and the signal receiving device. When the controller recognizes that the RSSI value of the wireless signal exceeds the corresponding set threshold, the controller starts to run the spatial triangulation positioning algorithm. The controller obtains the coordinates of the signal transmitting device through the spatial triangulation positioning algorithm, and then combines the size and layout of the monitoring area to accurately and quickly determine whether the intrusion template is in the monitoring area.
[0004] The technical solution adopted by the present invention is: an intrusion alarm system, including a controller, a signal transmitting device and three or more signal receiving devices, the signal transmitting device is installed on the monitored intrusion target, and the three or more signal receiving devices are installed at preset positions in the monitoring area to form a triangle or a triangular cone in three-dimensional space. The controller and the signal receiving device are connected, the signal transmitting device sends a wireless signal to the outside in real time, the signal receiving device receives the signal and the controller transmits the wireless signal in real time. When the controller identifies that the RSSI value of the wireless signal exceeds the corresponding set threshold, the controller starts to run a spatial triangulation positioning algorithm, obtains the coordinates of the signal transmitting device based on the known coordinates of the three or more signal receiving devices, and combines the size and layout of the monitoring area to determine whether the intrusion target is in the monitoring area. When the intrusion target is in the monitoring area, the controller generates an alarm message, and the alarm message includes location and time information; The RSSI threshold is set according to the shortest distance from the signal receiving device to the monitoring area and the distance formula, and the distance formula is: ; Wherein, d is the distance between the signal receiving device and the signal transmitting device; RSSI0 is the RSSI reference value when the signal receiving device is 1 meter away from the signal transmitting device; RSSI is the RSSI value currently received by the signal receiving device; and n is the environmental attenuation factor.
[0005] Furthermore, the monitored intrusion target is an electric bicycle or its battery, the signal transmitting device adopts the nRF52 series Bluetooth module, the signal receiving device adopts the CC2640R2F Bluetooth gateway module, the signal transmitting device is installed inside the battery casing of the electric bicycle, and the signal receiving device is located on the car wall on multiple different surfaces of the car.
[0006] Furthermore, the controller of the present application is also connected to the elevator control system. The elevator operation system is connected to a travel controller in the shaft on the first floor or the negative first floor. When the elevator car touches the travel switch of the floor, it indicates that the elevator has reached the floor. When the elevator reaches the floor, a start signal is sent to the elevator system and the signal is transmitted to the controller. The controller forwards the start signal to the signal receiving device, and the signal receiving device is started to receive the signal sent by the signal transmitting device.
[0007] Furthermore, the signal transmitting device specifically adopts nRF52840, including two crystal oscillator circuits, wherein the first crystal oscillator circuit includes crystal oscillators X1, C1 and C2, one end of capacitor C1 is connected to the XL1 interface of nRF52840, one end of capacitor C2 is connected to the XL2 interface of nRF52840, the other ends of capacitors C1 and C2 are both grounded, and crystal oscillator X1 is connected between one end of capacitor C1 and one end of capacitor C2; the second crystal oscillator circuit includes crystal oscillator X2, capacitors C3 and C4, one end of capacitor C3 is connected to the XC2 interface of nRF52840, one end of capacitor C4 is connected to the XC1 interface of nRF52840, the other ends of capacitors C3 and C4 are both grounded, crystal oscillator X2 is connected between one end of capacitor C3 and one end of capacitor C4, and the two crystal oscillator circuits are divided into generating high-speed clock and low-speed clock.
[0008] The present invention also provides a monitoring method, which is applied to a controller of an intrusion alarm system and comprises the following steps: S1: When the controller identifies that the RSSI value received by the signal receiving device exceeds the corresponding set threshold, the controller starts to run the spatial triangulation positioning algorithm; S2: The three signal receiving devices are respectively denoted as A, B and C, and the position coordinates of three or more known signal receiving devices are obtained. The position coordinates are respectively expressed as ( , )、( , )as well as( , ), the position coordinates of the signal transmitter are assumed to be (x, y), A, B and C measure the RSSI values from the signal transmitter respectively, and the three RSSI values are calculated and converted into distance according to the distance formula. , , , the distance formula is:
[0009] Wherein, d is the distance between the signal receiving device and the signal transmitting device; RSSI0 is the RSSI reference value when the signal receiving device is 1 meter away from the signal transmitting device; RSSI is the RSSI value currently received by the signal receiving device; and n is the environmental attenuation factor.
[0010] S3: List the following equations and solve them using Newton's iteration method to obtain the position coordinates (x, y) of the signal transmitter: ; ; = ; S4: The controller determines whether the signal transmitter is within the monitoring area of the car based on the calculated position coordinates (x, y) of the signal transmitter and the boundary coordinates of the monitoring area of the car. When it is determined that the signal transmitter is within the monitoring area of the car, the controller generates an alarm message, which includes position and time information.
[0011] Furthermore, in step S3, the steps of solving the system of equations are as follows: S31: Write the system of equations in functional form: ; ; ; List the iterative formula of Newton's iteration method: ,in, is the Jacobian matrix, is the function vector; List the Jacobian matrix: [ ] [ ] [ ] The function vector F consists of the individual function values: ; ; ; Compute partial derivatives: ; ; ; ; ; ; S32: Select an initial guess point , substitute into the Jacobian matrix and function vector F formula listed in step S31, and calculate the Jacobian matrix and function vector ; S33: Based on step S32, solve the linear equation system ,get = [ , ]; S34: Update iteration point: = ; S35: Repeat steps S32-S34 until the convergence condition is met ,in is any positive number.
[0012] Furthermore, it also includes step S5: the controller is connected to the centralized monitoring center of the building property. When the controller confirms that the intrusion target appears in the monitoring area, the controller generates an alarm message, the alarm message includes location and time information, and the controller sends the location and time information to the centralized monitoring center in a timely manner.
[0013] Furthermore, it also includes step S6: the controller is also connected to the elevator control system, the elevator control system is connected to at least one sound alarm, the sound alarm is set in the shaft on the first floor or the negative first floor, when the controller confirms that the intrusion target appears in the monitoring area, it sends an intrusion signal to the elevator control system, the elevator operation system controls the elevator not to start, the elevator control system stops the elevator from running upward or downward, and the sound alarm sounds an alarm to remind the intrusion target to stay away from the monitoring area until the controller confirms that there is no intrusion target in the monitoring area, and then continues normal operation.
[0014] The present invention also provides a monitoring device, which is applied to a controller of an intrusion alarm system, and the device comprises: Laser radar, which is connected to the controller and is used to scan the three-dimensional area around the monitoring area. The controller cuts and splices the acquired scanning data to obtain the boundary coordinates of the surrounding three-dimensional area; A first calculation module, used to substitute the shortest distance between the plurality of signal receiving devices and the boundary of the monitoring area into the distance formula to obtain the threshold value of the RSSI value of the corresponding signal receiving device; The first judgment module is used to judge whether the RSSI values currently received by the multiple signal receiving devices are greater than the corresponding set thresholds. If the RSSI value of any signal receiving device is greater than the set threshold, the spatial triangulation positioning algorithm is started; A second calculation module is used to calculate the position coordinates of the signal transmitting device according to the position coordinates of the plurality of signal receiving devices through spatial triangulation calculation; A second judgment module is used to judge whether the position coordinates of the signal transmitting device fall within the monitoring area according to the boundary coordinate values of the monitoring area preset in advance; The generation module generates alarm information including the location and time information of the signal transmitting device when confirming that the location coordinates of the signal transmitting device fall into the monitoring area.
[0015] The present application provides a monitoring method, device and battery vehicle intrusion alarm system. Based on RSSI value and triangular space algorithm, it can accurately identify whether there is an intrusion target in the monitoring area. It has a simple structure and a simple algorithm. It can quickly calculate the position coordinates of the signal transmitting device. Combined with the preset three-dimensional boundary coordinate data of the monitoring area of the car, it can quickly determine whether the intrusion target is in the car. The judgment method is accurate and fast, not limited to ground monitoring, and can be applied to intrusion detection in various complex environments. The ground coordinates are generally limited to plane coordinates, and three or more signal receiving devices are set to achieve multi-directional monitoring of the intrusion target; the signal receiving device and the signal transmitting device replace the traditional method of detecting whether there is an intrusion target in the elevator through image or visual recognition. The method has higher accuracy and is still applicable to people who deliberately hide the intrusion target, and there will be no misjudgment. It is particularly suitable for use in some occasions that are not easy to identify through the visual system, or in the case of hidden intrusion, to increase the safety and reliability of the intrusion alarm system; the controller starts the algorithm after the RSSI value reaches the threshold, which can avoid the controller being in complex calculations all the time, reduce energy consumption and improve energy utilization efficiency. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 This is a schematic diagram of the installation of the signal transmitting device according to Example 1 of the present invention.
[0017] Figure 2 This is a schematic diagram of the installation of the signal receiving device according to Embodiment 1 of the present invention.
[0018] Figure 3 This is a schematic diagram of a signal receiving device chip according to Embodiment 1 of the present invention.
[0019] Figure 4 This is a flow chart of Example 3 of the present invention. DETAILED DESCRIPTION
[0020] In order to make the purpose, technical solution and advantages of the present invention more clear, the technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings and a preferred implementation manner. Example 1
[0021] Embodiment 1 of the present application provides an intrusion alarm system, which includes a controller, a signal transmitting device and three or more signal receiving devices, wherein the signal transmitting device is installed on the monitored intrusion target, and the three or more signal receiving devices are installed at preset positions of the monitoring area to form a triangle or a triangular cone in a three-dimensional space, the controller and the signal receiving device are connected, the signal transmitting device sends a wireless signal to the outside in real time, the signal receiving device receives the signal and the controller transmits the wireless signal in real time, when the controller identifies that the RSSI value of the wireless signal exceeds the corresponding set threshold, the controller starts to run a spatial triangulation positioning algorithm, obtains the coordinates of the signal transmitting device based on the known coordinates of the three or more signal receiving devices, and combines the size and layout of the monitoring area to determine whether the intrusion target is within the monitoring area, when the intrusion target is within the monitoring area, the controller generates an alarm message, and the alarm message includes location and time information; The RSSI threshold is set according to the shortest distance from the signal receiving device to the monitoring area and the distance formula, and the distance formula is:
[0022] Wherein, d is the distance between the signal receiving device and the signal transmitting device; RSSI0 is the RSSI reference value when the signal receiving device is 1 meter away from the signal transmitting device, which needs to be obtained through experimental measurement; RSSI is the RSSI value currently received by the signal receiving device; n is the environmental attenuation factor, which is usually between 2 and 4, and the specific value needs to be determined according to the actual environment.
[0023] The monitored intrusion target in Example 1 of the present application is an electric bicycle or its battery, the monitoring area is the elevator cabin space, the signal transmitting device adopts the nRF52 series Bluetooth module, and the signal receiving device adopts the highly sensitive CC2640R2F Bluetooth gateway module. Figure 1 The signal transmitting device is installed inside the battery shell of the electric bicycle, and it is not convenient to remove the signal transmitting device. Therefore, even if the user of the electric bicycle removes the battery and takes it into the elevator, it will be identified. The signal receiving device is installed in the elevator car and can be located at least one of the top, middle, and bottom of the car. In this embodiment, there are three signal receiving devices, which are located on the walls of three different surfaces of the car to form a triangle or a triangular cone in three-dimensional space.
[0024] refer to Figure 2 The three signal receiving devices of Example 1 of the present application are arranged on the innermost side and the left and right sides of the car, namely A, B and C. The shortest distance between the three signal receiving devices and the boundary area of the car is assumed to be d, or the size of d is adjusted according to needs. The RSSI reference value of the signal receiving device 1 meter away from the signal transmitting device is measured, and the RSSI value is calculated according to the distance formula. This RSSI value is the threshold.
[0025] In specific applications, the staff can determine the number of signal receiving devices to be set and the position of each signal receiving device according to the surrounding three-dimensional area of the monitored area and the scanning range of the signal receiving device and the signal transmitting device to achieve the best recognition effect.
[0026] Specifically, in this embodiment, the method for obtaining the boundary position coordinates of the monitoring area is as follows: the three-dimensional area surrounding the monitoring area is scanned by a laser radar, and the controller crops and splices the acquired scanning data to obtain spatial data of the surrounding three-dimensional area. The data obtained by this method is more accurate.
[0027] The controller of Example 1 of the present application is connected to the centralized monitoring center of the property of the building. When the controller confirms that the intrusion target appears in the monitoring area, the location and time information is sent to the centralized monitoring center in a timely manner. The staff of the centralized monitoring center can call the monitoring video according to the location and time, find the target resident at the first time, and remind them to take the intrusion target out of the building.
[0028] The controller of the present application is also connected to the elevator control system, and the elevator control system is connected to at least one sound alarm. The sound alarm is set in the shaft on the first floor or the negative first floor. A sound alarm can also be set on each floor according to actual needs. The elevator control system is programmable for each elevator. When the controller confirms that the intrusion target appears in the monitoring area, it sends an intrusion signal to the elevator control system. The elevator's operating system controls the elevator not to start, and the elevator control system stops the elevator from running up or down. The sound alarm also sounds an alarm to remind the intrusion target to stay away from the monitoring area until the controller confirms that there is no intrusion target in the monitoring area and then continues to operate normally.
[0029] In some other embodiments, the elevator operation system of the present application is connected to a travel controller in the shaft on the first floor or the negative first floor. When the elevator car touches the travel switch of the floor, it indicates that the elevator has reached the floor. When the elevator reaches the floor, a start signal is sent to the elevator system and the signal is transmitted to the controller. The controller forwards the start signal to the signal receiving device, and the signal receiving device is started to receive the signal sent by the signal transmitting device. The present application mainly prevents electric vehicles or batteries from being brought into the building to prevent misjudgment, such as situations where residents in the building take electric vehicles or batteries out by taking the elevator.
[0030] refer to Figure 3The signal transmitting device of the present application adopts the Bluetooth module of the nRF52 series, specifically the nRF52840, which has a 32-bit ARM Cortex-M4 processor, has powerful computing power and low power consumption, has a large memory, has good stability and a long communication distance. The working power supply of nRF52840 is 1.7V-5.5V. The power acquisition method of this embodiment selects to connect a 5V power adapter to power supply through an external DC power interface (VDDH). nRF52840 includes two crystal oscillator circuits, wherein the first crystal oscillator circuit includes crystal oscillator X1, C1 and C2, one end of capacitor C1 is connected to the XL1 interface of nRF52840, one end of capacitor C2 is connected to the XL2 interface of nRF52840, the other ends of capacitors C1 and C2 are grounded, and crystal oscillator X1 is connected between one end of capacitor C1 and one end of capacitor C2; the second crystal oscillator circuit includes crystal oscillator X2, capacitors C3 and C4, one end of capacitor C3 is connected to the XC2 interface of nRF52840, one end of capacitor C4 is connected to the XC1 interface of nRF52840, the other ends of capacitors C3 and C4 are grounded, crystal oscillator X2 is connected between one end of capacitor C3 and one end of capacitor C4, and the two crystal oscillator circuits are divided into generating high-speed clock and low-speed clock.
[0031] The intrusion alarm system provided by the present application replaces the traditional method of detecting whether there is an electric vehicle in the elevator through image recognition by using a signal receiving device and a signal transmitting device. It has higher accuracy and is still applicable to people who deliberately hide electric vehicles or batteries, and there will be no misjudgment. Based on the RSSI value and the triangular space algorithm, it can accurately identify whether there is an intrusion target in the monitored area. The algorithm is started after the RSSI value reaches the threshold, which can avoid the controller being in complex calculations all the time, reduce energy consumption and improve energy utilization efficiency. The nRF52 series Bluetooth module is used, which has high receiving sensitivity, large memory and flexible power management, further increasing the accuracy of the system and battery durability and life.
[0032] The present application also provides a monitoring method, which is applied to the controller of the intrusion alarm system in Example 1. The controller may be an electronic device with computing functions. The intrusion alarm system includes a signal transmitting device and three or more signal receiving devices.
[0033] The monitoring method includes the following steps: S1: When the controller identifies that the RSSI value received by the signal receiving device exceeds the corresponding set threshold, the controller starts to run the spatial triangulation positioning algorithm; S2: The three signal receiving devices are respectively denoted as A, B and C, and the position coordinates of three or more known signal receiving devices are obtained. The position coordinates are respectively expressed as ( , )、( , )as well as( , ), the position coordinates of the signal transmitter are assumed to be (x, y), A, B and C measure the RSSI values from the signal transmitter respectively, and the three RSSI values are calculated and converted into distance according to the distance formula. , , , the distance formula is;
[0034] Wherein, d is the distance between the signal receiving device and the signal transmitting device; RSSI0 is the RSSI reference value when the signal receiving device is 1 meter away from the signal transmitting device, which needs to be obtained through experimental measurement; RSSI is the RSSI value currently received by the signal receiving device; n is the environmental attenuation factor, which is usually between 2 and 4, and the specific value needs to be determined according to the actual environment.
[0035] S3: List the following equations and solve them using Newton's iteration method to obtain the position coordinates (x, y) of the signal transmitter: ; ; = ; S4: The controller determines whether the signal transmitter is within the monitoring area of the car based on the calculated position coordinates (x, y) of the signal transmitter and the boundary coordinates of the monitoring area of the car. When it is determined that the signal transmitter is within the monitoring area of the car, the controller generates an alarm message, which includes position and time information.
[0036] Specifically, in the above step S3, the steps of solving the equation system are as follows: S31: Write the system of equations in functional form: ; ; ; List the iterative formula of Newton's iteration method: ,in, is the Jacobian matrix, is a function vector.
[0037] List the Jacobian matrix: [ ] [ ] [ ] The function vector F consists of the individual function values: ; ; ; Compute partial derivatives: ; ; ; ; ; ; S32: Select an initial guess point , bring it into the Jacobian matrix and function vector formula listed in step S31, and calculate the Jacobian matrix and function vector ;
[0038] S33: Based on step S32, solve the linear equation system ,get =[ , ];
[0039] S34: Update iteration point: = ;
[0040] S35: Repeat steps S32-S34 until the convergence condition is met ,in is any positive number.
[0041] In some other embodiments, in order to improve the positioning accuracy of the signal transmitting device, multiple RSSI measurements are performed on each Bluetooth transmitter to reduce errors. After the position of the receiver R is calculated, it is determined whether the Bluetooth receiver is within the elevator car position range.
[0042] Furthermore, this embodiment also includes step S5: the controller is connected to the centralized monitoring center of the property of the building. When the controller confirms that the intrusion target appears in the monitoring area, the controller generates an alarm message, and the alarm message includes location and time information. The controller sends the location and time information to the centralized monitoring center in a timely manner. The staff of the centralized monitoring center can call the monitoring video according to the location and time, find the target resident at the first time, and remind them to take the intrusion target out of the building.
[0043] Furthermore, this embodiment also includes step S6: the controller is also connected to the elevator control system, the elevator control system is connected to at least one sound alarm, the sound alarm is set in the shaft on the first floor or the negative first floor, when the controller confirms that the intrusion target appears in the monitoring area, it sends an intrusion signal to the elevator control system, the elevator operation system controls the elevator not to start, the elevator control system stops the elevator from running upward or downward, and the sound alarm sounds an alarm, the specific alarm content is: electric bicycles are not allowed to enter the elevator to remind the intrusion target to stay away from the monitoring area, until the controller confirms that there is no intrusion target in the monitoring area, it will continue to operate normally.
[0044] Through the monitoring method of the present application, in combination with the intrusion alarm system of Example 1, the position coordinates of the signal transmitting device can be quickly calculated. Combined with the preset boundary coordinate points of the monitoring area of the car, it is possible to quickly determine whether the intrusion target is in the car. The judgment method is accurate and fast. If an intrusion target is determined, an alarm can be immediately sent to the centralized monitoring center of the property, and the elevator can also be stopped from running upward or downward. The sound alarm can also sound an alarm to avoid the situation where the property personnel cannot arrive at the scene in time and stop the passengers. Example 3
[0045] refer to Figure 4 The present application also provides a monitoring device, which is applied to the intrusion alarm system described in Example 1. The intrusion alarm system includes a signal transmitting device and three or more signal receiving devices. The monitoring device includes: The laser radar is connected to the controller. The laser radar is used to scan the three-dimensional area around the monitoring area to obtain scanning data. The controller cuts and splices the acquired scanning data to obtain the boundary coordinates of the surrounding three-dimensional area, and stores the boundary coordinate values in the controller in advance; A first calculation module, used to substitute the shortest distance between the plurality of signal receiving devices and the boundary of the monitoring area into the distance formula to obtain the threshold value of the RSSI value of the corresponding signal receiving device; The first judgment module is used to judge whether the RSSI values currently received by the multiple signal receiving devices are greater than the corresponding set thresholds. When the RSSI value of any signal receiving device is greater than the corresponding set threshold, the spatial triangulation positioning algorithm is started; A second calculation module is used to calculate the position coordinates of the signal transmitting device according to the position coordinates of the plurality of signal receiving devices through spatial triangulation calculation; The second judgment module is used to judge whether the position coordinates of the current signal transmitting device fall within the monitoring area according to the boundary coordinate values of the monitoring area preset in advance; The generation module generates alarm information including the location and time information of the signal transmitter when confirming that the location coordinates of the signal transmitter fall within the monitoring area.
[0046] Furthermore, the monitoring device also includes a communication module, which is used to transmit alarm information to a connected monitoring center.
[0047] Furthermore, the monitoring device also includes an alarm module and an emergency stop module. The alarm module is used for warning, and the emergency stop module is used for stopping the operation of some equipment in the monitoring area.
[0048] The monitoring device provided by the present application has a signal transmitting device arranged on the intrusion target, the signal transmitting device transmits the signal in real time, the signal receiving device receives the identification signal in real time, and the signal receiving device receives the RSSI value in real time. If the RSSI value of any signal receiving device is greater than the set threshold value, the spatial triangulation positioning algorithm starts to run to realize multi-directional monitoring of the intrusion target. The spatial triangulation positioning algorithm can accurately identify the position coordinates of the intrusion target. Once the intrusion target is identified, an alarm message can be generated and sent to the monitoring center. The device has a simple structure, a simple algorithm, and a very low cost. It realizes intrusion monitoring and alarm, and is particularly suitable for use in some occasions that are not easy to identify through a visual system, or in the presence of hidden intrusions, to increase the safety and reliability of the intrusion alarm system.
[0049] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications are also within the protection scope of the present invention.
Claims
1. An intrusion alarm system, characterized in that: The system includes a controller, a signal transmitting device and three or more signal receiving devices. The signal transmitting device is installed on the monitored intrusion target, and the three or more signal receiving devices are installed at preset positions in the monitoring area to form a triangle or a triangular cone in three-dimensional space. The controller and the signal receiving device are connected. The signal transmitting device sends a wireless signal to the outside in real time, and the signal receiving device receives the signal and the controller transmits the wireless signal in real time. When the controller identifies that the RSSI value of the wireless signal exceeds the corresponding set threshold, the controller starts to run the spatial triangulation positioning algorithm, obtains the coordinates of the signal transmitting device based on the known coordinates of the three or more signal receiving devices, and combines the size and layout of the monitoring area to determine whether the intrusion target is in the monitoring area. When the intrusion target is in the monitoring area, the controller generates an alarm message, and the alarm message includes location and time information; The RSSI threshold is set according to the shortest distance from the signal receiving device to the monitoring area and the distance formula, and the distance formula is: ; Wherein, d is the distance between the signal receiving device and the signal transmitting device; RSSI0 is the RSSI reference value when the signal receiving device is 1 meter away from the signal transmitting device; RSSI is the RSSI value currently received by the signal receiving device; n is the environmental attenuation factor.
2. An intrusion alarm system according to claim 1, characterized in that: The monitored intrusion target is an electric bicycle or its battery. The signal transmitter adopts the nRF52 series Bluetooth module, and the signal receiver adopts the CC2640R2F Bluetooth gateway module. The signal transmitter is installed inside the battery shell of the electric bicycle, and the signal receiver is located on the walls of the car on different sides.
3. An intrusion alarm system according to claim 1, characterized in that: The controller of the present application is also connected to the elevator control system. The elevator operation system is connected to a travel controller in the shaft on the first floor or the negative first floor. When the elevator car touches the travel switch of the floor, it indicates that the elevator has reached the floor. When the elevator reaches the floor, a start signal is sent to the elevator system and the signal is transmitted to the controller. The controller forwards the start signal to the signal receiving device, and the signal receiving device is started to receive the signal sent by the signal transmitting device.
4. An intrusion alarm system according to claim 2, characterized in that: The signal transmitting device specifically adopts nRF52840, including two crystal oscillator circuits, wherein the first crystal oscillator circuit includes crystal oscillator X1, C1 and C2, one end of capacitor C1 is connected to the XL1 interface of nRF52840, one end of capacitor C2 is connected to the XL2 interface of nRF52840, the other ends of capacitors C1 and C2 are grounded, and crystal oscillator X1 is connected between one end of capacitor C1 and one end of capacitor C2; the second crystal oscillator circuit includes crystal oscillator X2, capacitors C3 and C4, one end of capacitor C3 is connected to the XC2 interface of nRF52840, one end of capacitor C4 is connected to the XC1 interface of nRF52840, the other ends of capacitors C3 and C4 are grounded, crystal oscillator X2 is connected between one end of capacitor C3 and one end of capacitor C4, and the two crystal oscillator circuits are divided into generating high-speed clock and low-speed clock.
5. A monitoring method, applied to the controller of the intrusion alarm system according to any one of claims 1 to 4, characterized in that: The steps include: S1: When the controller identifies that the RSSI value received by the signal receiving device exceeds the corresponding set threshold, the controller starts to run the spatial triangulation positioning algorithm; S2: The three signal receiving devices are respectively denoted as A, B and C, and the position coordinates of three or more known signal receiving devices are obtained. The position coordinates are respectively expressed as ( , )、( , )as well as( , ), the position coordinates of the signal transmitter are assumed to be (x, y), A, B and C measure the RSSI values from the signal transmitter respectively, and the three RSSI values are calculated and converted into distance according to the distance formula. , , , the distance formula is: ; Wherein, d is the distance between the signal receiving device and the signal transmitting device; RSSI0 is the RSSI reference value when the signal receiving device is 1 meter away from the signal transmitting device; RSSI is the RSSI value currently received by the signal receiving device; n is the environmental attenuation factor; S3: List the following equations and solve them using Newton's iteration method to obtain the position coordinates (x, y) of the signal transmitter: ; ; = ; S4: The controller determines whether the signal transmitting device is within the monitoring area of the car based on the position coordinates (x, y) of the signal transmitting device obtained in step S3 and the boundary coordinates of the monitoring area of the car. When it is determined that the signal transmitting device is within the monitoring area of the car, the controller generates an alarm message, which includes position and time information.
6. A monitoring method according to claim 5, characterized in that: In the above step S3, the steps of solving the equation system are as follows: S31: Write the system of equations in functional form: ; ; ; List the iterative formula of Newton's iteration method: ; in, is the Jacobian matrix, is the function vector; List the Jacobian matrix: [ ] [ ] [ ] The function vector F consists of the individual function values: ; ; ; Compute partial derivatives: ; ; ; ; ; ; S32: Select an initial guess point , substitute into the Jacobian matrix and function vector F formula listed in step S31, and calculate the Jacobian matrix and function vector ; S33: Based on step S32, solve the linear equation system ,get = [ , ]; S34: Update iteration point: = ; S35: Repeat steps S32-S34 until the convergence condition is met ,in is any positive number.
7. A monitoring method according to claim 5, characterized in that: It also includes step S5: the controller is connected to the centralized monitoring center of the building property. When the controller confirms that the intrusion target appears in the monitoring area, the controller generates an alarm message, and the alarm message includes location and time information. The controller sends the location and time information to the centralized monitoring center in a timely manner.
8. A monitoring method according to claim 7, characterized in that: It also includes step S6: the controller is also connected to the elevator control system, the elevator control system is connected to at least one sound alarm, the sound alarm is set in the shaft on the first floor or the negative first floor, when the controller confirms that the intrusion target appears in the monitoring area, it sends an intrusion signal to the elevator control system, the elevator operation system controls the elevator not to start, the elevator control system stops the elevator from running up or down, and the sound alarm sounds an alarm to remind the intrusion target to stay away from the monitoring area until the controller confirms that there is no intrusion target in the monitoring area, and then continues normal operation.
9. A monitoring device, applied to the controller of the intrusion alarm system according to any one of claims 1 to 4, characterized in that: The device includes: Laser radar, which is connected to the controller and is used to scan the three-dimensional area around the monitoring area. The controller cuts and splices the acquired scanning data to obtain the boundary coordinates of the surrounding three-dimensional area; A first calculation module, used to substitute the shortest distance between the plurality of signal receiving devices and the boundary of the monitoring area into the distance formula to obtain the threshold value of the RSSI value of the corresponding signal receiving device; The first judgment module is used to judge whether the RSSI values currently received by the multiple signal receiving devices are greater than the corresponding set thresholds. If the RSSI value of any signal receiving device is greater than the set threshold, the spatial triangulation positioning algorithm is started; A second calculation module is used to calculate the position coordinates of the signal transmitting device according to the position coordinates of the plurality of signal receiving devices through spatial triangulation calculation; The second judgment module is used to judge whether the position coordinates of the signal transmitting device fall within the monitoring area according to the boundary coordinate values of the monitoring area preset in advance; The generation module generates alarm information including the location and time information of the signal transmitting device when confirming that the location coordinates of the signal transmitting device fall into the monitoring area.
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