Living body detection system, detection method and electronic equipment

Abstract

The invention discloses a living body detection system and method and electronic equipment, and belongs to the technical field of target detection. The living body detection system comprises: a rotation module; the UWB radar is arranged at the output end of the rotating module; the control module is electrically connected with the rotating module and the UWB radar; wherein the rotating module drives the UWB radar to sequentially rotate to a plurality of designated positions, the UWB radar transmits and receives UWB radar signals at the designated positions for multi-point detection, and the UWB radar signals are transmitted to the control module. According to the invention, the rotating module is adopted to drive the UWB radar to rotate to a plurality of designated positions, so that the UWB radar can carry out multi-point detection on the living body from different angle positions, the specific position of the living body can be obtained according to the UWB radar signals of multi-point detection, and the detection precision is improved.

Description

Technical Field

[0001] The present application relates to the field of target detection technology, and in particular to a living body detection system, a detection method and an electronic device. Background Art

[0002] At present, the in-vehicle living body monitoring system uses in-vehicle sensors, cameras or infrared sensing devices to determine whether there are living things left in the car and conduct monitoring. However, usually the camera or infrared sensing device performs single-point detection of living things at a fixed position, and the detection result is low in accuracy.

[0003] With respect to the above-mentioned problems existing in the related technologies, no effective solutions have been found so far. Summary of the invention

[0004] The present application provides a living body detection system, a detection method and an electronic device to solve the above-mentioned technical problems existing in the related art.

[0005] The living body detection system according to the present application includes: a rotating module; a UWB radar, which is arranged at the output end of the rotating module; and a control module, which is electrically connected to the rotating module and the UWB radar; wherein the rotating module drives the UWB radar to rotate to a plurality of designated positions in sequence, the UWB radar sends and receives UWB radar signals at the plurality of designated positions for multi-point detection, and transmits the UWB radar signals to the control module.

[0006] According to the living body detection system of the present application, the rotating module includes a display device and an active mechanism, and the display device is rotatably connected to the active mechanism.

[0007] According to the living body detection system of the present application, the active mechanism includes a driving component and a transmission component, the driving component is drivingly connected to the transmission component, and the driving component has a built-in first sensor.

[0008] Optionally, the display device includes a first edge and a second edge, the first edge and the second edge are parallel to the rotation axis of the display device, the first edge is close to the rotation axis of the display device, and the second edge is far from the rotation axis of the display device, and the UWB radar is arranged at the second edge.

[0009] Optionally, the rotating module further includes a driven mechanism, the driven mechanism is connected to the display device, and the driven mechanism has a built-in second sensor.

[0010] According to the living body detection system of the present application, the UWB radar includes a transmitting antenna and a receiving antenna, and both the transmitting antenna and the receiving antenna are directional antennas.

[0011] According to the detection method of the present application, it is used for the above-mentioned living body detection system to execute, and the detection method includes: controlling the UWB radar to rotate to multiple designated positions in sequence; controlling the UWB radar to send and receive UWB radar signals at each of the designated positions to determine whether there is a living body in the target vehicle; if a living body is detected in the target vehicle, the specific position of the living body is calculated based on the UWB signal at each of the designated positions.

[0012] Optionally, the multiple designated positions include a first designated position and a second designated position, and the calculating the specific position of the living body according to the UWB signal at each of the designated positions includes:

[0013] Acquire a first position coordinate of the first designated position, and acquire a first UWB radar signal at the first designated position;

[0014] Acquire the second position coordinates of the second designated position, and acquire the second UWB radar signal at the second designated position;

[0015] Calculate a first distance between the first designated position and the living body according to the first UWB radar signal; calculate a second distance between the second designated position and the living body according to the second UWB radar signal; and calculate a third distance between the first designated position and the second designated position;

[0016] The center position coordinates of the rotation axis of the display device are obtained, and in a plane formed by the center position coordinates, the first position coordinates and the second position coordinates, the two-dimensional living body position coordinates are calculated based on the first position coordinates, the second position coordinates, the first distance, the second distance and the third distance.

[0017] Optionally, the UWB radar includes a transmitting antenna and two receiving antennas. After calculating the two-dimensional living body position coordinates of the living body, the detection method further includes:

[0018] Calculating the phase difference between the UWB radar signals received by the two receiving antennas at any detection position;

[0019] Constructing a straight line between the actual position of the living body and the UWB radar, and calculating an angle between the straight line and the plane according to the phase difference;

[0020] Calculating the distance between the actual position of the living body and the plane according to the angle;

[0021] The distance and the two-dimensional living body position coordinates are used as the three-dimensional living body position coordinates of the detected object.

[0022] The electronic device according to the present application includes a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory communicate with each other through the communication bus; wherein:

[0023] Memory, used to store computer programs;

[0024] The processor is used to execute the steps in the above detection method by running the program stored in the memory.

[0025] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0026] According to the living body detection system of the present application, a rotating module is used to drive the UWB radar to rotate to multiple specified positions, so that the UWB radar can perform multi-point detection of the living body from different angles and positions. The specific position of the living body can be obtained based on the UWB radar signal of the multi-point detection, thereby improving the detection accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0028] Figure 1 is a first component block diagram of a living body detection system according to an embodiment of the present application;

[0029] Figure 2 is a schematic diagram of the structure of the rotating module in an embodiment of the present application;

[0030] Figure 3 It is a structural diagram of the active mechanism in the embodiment of the present application;

[0031] Figure 4 is a flow chart of a method for detecting a living body in a vehicle according to an embodiment of the present application;

[0032] Figure 5 is a schematic diagram of calculating the two-dimensional position coordinates of a living body in an embodiment of the present application;

[0033] Figure 6 is a schematic diagram of calculating the two-dimensional position coordinates of a living body in the first scenario in an embodiment of the present application;

[0034] Figure 7 is a schematic diagram of calculating the two-dimensional position coordinates of a living body in the second scenario in an embodiment of the present application;

[0035] Figure 8 is a schematic diagram of calculating the two-dimensional position coordinates of a living body in the third scenario in an embodiment of the present application;

[0036] Fig. 9 is a schematic diagram of calculating the three-dimensional position coordinates of a living body in an embodiment of the present application;

[0037] Fig.10 is a second block diagram of the living body detection system in an embodiment of the present application;

[0038] Fig.11 is a flow chart of an implementation method of in-vehicle living body detection in an embodiment of the present application;

[0039] Fig.12 It is a hardware structure block diagram of a computer according to an embodiment of the present application. Description of the drawings:

[0041] Display device 10, first edge 11, second edge 12, active mechanism 20, driving component 21, brushless motor 211, transmission component 22, first output shaft 221, driven mechanism 30, synchronous gear set 31, transmission gear 311, second output shaft 32, UWB radar 2, processor 402, memory 404, transmission device 406, input and output device 408. DETAILED DESCRIPTION

[0042] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only embodiments of a part of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work should fall within the scope of protection of the present application. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0043] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0044] like Figure 1 , Figure 2 as well as Figure 3As shown, the living body detection system according to the embodiment of the present application includes: a rotation module, a UWB radar 2 and a control module.

[0045] Specifically, the UWB radar 2 is arranged at the output end of the rotating module; the control module is electrically connected to the rotating module and the UWB radar 2; wherein the rotating module drives the UWB radar 2 to rotate to a plurality of designated positions in sequence, and the UWB radar 2 sends and receives UWB radar signals at the plurality of designated positions for multi-point detection, and transmits the UWB radar signals to the control module.

[0046] Specifically, the live body detection system includes a rotation module, a UWB radar 2 and a control module (MCU / CPU). The UWB radar 2 is arranged at the output end of the rotation module, and the rotation module drives the UWB radar 2 to rotate to multiple designated positions in sequence for multi-point detection. The UWB radar 2 transmits and receives UWB radar signals at each designated position, and transmits the UWB radar signals to the control module, which performs live body detection and specific position calculation based on the UWB radar signals at multiple designated positions.

[0047] For example, in a specific embodiment, the specific detection process is as follows:

[0048] Step 1. The rotating module drives the UWB radar 2 to rotate to the first designated position; Step 2. The UWB radar 2 transmits a UWB radar signal at the position and receives the reflected UWB radar signal; Step 3. The control module receives the UWB radar signal and analyzes and processes it to determine whether there is a living body at the position; Step 4. The rotating module drives the UWB radar 2 to move to the next designated position and repeats steps 2 and 3; Step 5. The control module performs a comprehensive analysis based on the UWB radar signals at multiple designated positions to determine the position of the living body.

[0049] In this embodiment, an ultra-wideband (UWB) radar is preferably used for living body detection. The UWB radar 2 can detect the breathing and heartbeat signals of living bodies (such as humans or animals).

[0050] According to the living body detection system of the embodiment of the present application, a rotating module is used to drive the UWB radar 2 to rotate to multiple specified positions, so that the UWB radar 2 can perform multi-point detection of the living body from different angles and positions. The specific position of the living body can be calculated based on the UWB radar signal of the multi-point detection, thereby improving the detection accuracy.

[0051] According to the living body detection system of the embodiment of the present application, the rotation module includes a display device 10 and an active mechanism 20 , and the display device 10 is rotatably connected to the active mechanism 20 .

[0052] In detail, the active mechanism 20 can generate a rotational force through a motor or other power source and transmit the rotational force to the display device 10. The active mechanism 20 can adjust the rotation speed to adapt to different display requirements or requirements for liveness detection. The active mechanism 20 can also ensure that the display device 10 can remain stable during rotation to avoid shaking or imbalance.

[0053] According to the living body detection system of the embodiment of the present application, the active mechanism 20 includes a driving component 21 and a transmission component 22. The driving component 21 is drivingly connected to the transmission component 22, and the driving component 21 has a built-in first sensor.

[0054] In detail, the driving assembly 21 is responsible for providing power, while the transmission assembly 22 transmits the power to the load or the actuator. Such a design can effectively realize power conversion and control.

[0055] The driving component 21 includes a motor, a hydraulic pump or a pneumatic device. The first sensor built into the driving component 21 can monitor the state of the driving component 21 in real time, such as parameters such as rotation speed, position or temperature, so as to realize feedback control.

[0056] In addition, the transmission component 22 can transmit the power generated by the drive component 21 to the load through gears, belts, worm gears, etc. In some embodiments, it can also include a reducer to adjust the torque and torque output by the drive component 21.

[0057] In a specific embodiment, the active mechanism 20 includes a brushless motor 211, and the transmission assembly 22 includes a first output shaft 221. The brushless motor 211 provides power and transmits it to the first output shaft 221. The first output shaft 221 is connected to the display device 10 for driving the display device 10 to rotate. The first sensor is configured as a Hall sensor. The brushless motor 211 has a built-in Hall sensor. The Hall sensor monitors the rotation speed of the brushless motor 211 and controls the brushless motor 211 to rotate at a constant rotation speed through the motor driver chip.

[0058] In some embodiments, the brushless motor 211 is provided with an encoder so that the rotation angle of the display device 10 can be accurately controlled to achieve the desired display effect and the requirement for living body detection.

[0059] In some embodiments, the display device 10 includes a first edge 11 and a second edge 12, the first edge 11 and the second edge 12 are parallel to the rotation axis of the display device 10, and the first edge 11 is close to the rotation axis of the display device 10, and the second edge 12 is far away from the rotation axis of the display device 10, and the UWB radar 2 is arranged at the second edge 12.

[0060] In detail, arranging the UWB radar 2 at the second edge 12 has the following advantages: since the second edge 12 is far from the rotation axis, the UWB radar 2 can detect and monitor in a larger range, thereby increasing the monitoring coverage area of ​​the UWB radar 2; at the same time, arranging the UWB radar 2 at a position far from the rotation axis can reduce the interference of the rotating parts on the UWB radar signal, ensure that the UWB radar 2 can receive the return signal more clearly, and improve the detection accuracy of the UWB radar 2; in addition, such an arrangement can also enable the UWB radar 2 to perform multi-directional detection more flexibly, which is more conducive to monitoring the position and movement of the living body and reducing the detection blind spot; in addition, the UWB radar 2 works at a high frequency and can provide high-resolution imaging capabilities. At a position far from the rotation axis, it can make signal processing more effective, reduce the influence of the shadow area caused by the display device 10, and help to better identify and classify the detected living body. It should also be added that arranging the UWB radar 2 at a position far from the rotation axis can also help protect the UWB radar 2 from mechanical damage, while also avoiding possible failures or malfunctions, thereby improving safety.

[0061] like Figure 2 and Figure 3 As shown, in some embodiments, the rotating module further includes a driven mechanism 30 , which is connected to the display device 10 , and the driven mechanism 30 has a built-in second sensor.

[0062] In detail, a second sensor is built into the driven mechanism 30, which can facilitate the control module to monitor the angular position of the driven mechanism 30 to ensure that it is at the correct angle; the second sensor can also provide data on the rotation angle of the driven mechanism 30 to the control module, thereby helping the control module to adjust the operating parameters; in addition, the second sensor is also beneficial for assisting the control module to monitor abnormal operating conditions. At the same time, the second sensor can also cooperate with the first sensor to work together, thereby improving the overall coordination level of the liveness detection system under the control of the control module.

[0063] According to the liveness detection system of the embodiment of the present application, a second sensor can be used to detect the position or state of the driven mechanism 30, and the information can be fed back to the control module, so that the control module can monitor the movement of the driven mechanism 30 in real time, so as to facilitate accurate control and adjustment of the display device 10.

[0064] like Figure 2 and Figure 3As shown, in a specific embodiment, the driven mechanism 30 includes a second output shaft 32, the second output shaft 32 is fixedly connected to the display device 10, a pair of mutually meshing synchronous gear sets 31 are fixedly arranged on the second output shaft 32, the synchronous gear set 31 rotates with the display device 10, a magnet is arranged on the synchronous gear set 31, the second sensor is configured as a magnetic encoder, the magnetic encoding sensor is arranged opposite to the magnet, the magnetic encoding sensor detects the change of the magnetic field generated by the rotation of the magnet, and measures the rotation angle of the display device 10.

[0065] In this embodiment, the magnetic encoding sensor on the driven mechanism 30 can accurately determine the rotation angle of the display device 10 by detecting the changes in the magnetic field generated by the rotation of the magnet in real time, ensuring the accuracy of controlling the display device 10 to hover at any position, thereby improving the detection accuracy when performing living body position detection at a specified position.

[0066] In this embodiment, the two transmission gears 311 of the synchronous gear set 31 have the same module and number of teeth, and the two transmission gears 311 rotate synchronously. That is, a transmission gear 311 is fixed on the second output shaft 32 to rotate with the display device 10, and another transmission gear 311 with the same module and number of teeth is meshed with the driven mechanism 30. The rotation speeds of the meshed transmission gears 311 are exactly the same, and they rotate synchronously. Since the transmission gears 311 are the same in size, the angle synchronization can be ensured when meshing, so as to achieve the synchronous angle of the magnetic encoder and the angle of the display device 10.

[0067] According to the living body detection system of the embodiment of the present application, the UWB radar 2 includes a transmitting antenna and a receiving antenna, and both the transmitting antenna and the receiving antenna are directional antennas.

[0068] In detail, the transmitting antenna is configured as a directional antenna, which can effectively send the ultra-wideband signal to the target, and the directional transmission can increase the effective distance and accuracy of the signal. At the same time, the transmitting antenna can adopt beamforming technology to optimize the propagation direction of the signal; the receiving antenna is used to receive the signal reflected from the target. Directional reception helps to improve the signal-to-noise ratio and reduce the interference of background noise. At the same time, the directionality of the receiving antenna can help determine the direction and position of the target.

[0069] Directional antennas can improve the efficiency of signal transmission and reception, and directional antennas can be concentrated in a specific direction, thereby enhancing signal strength and reducing interference; at the same time, the UWB radar 2 itself has a high time resolution, and combined with a directional antenna, it can locate the target more accurately and improve detection accuracy; in addition, since the signal is concentrated in a specific direction, a directional antenna usually requires a lower transmission power, thereby reducing the energy consumption of the system; in addition, a directional antenna helps to filter out interference signals from non-target directions, thereby improving the reliability of the living thing detection system in complex environments.

[0070] like Figure 4 As shown, the detection method according to the embodiment of the present application is used for execution by the above-mentioned living body detection system, and the detection method includes:

[0071] Step S10: controlling the UWB radar 2 to rotate to a plurality of designated positions in sequence;

[0072] Step S20: Control the UWB radar 2 to send and receive UWB radar signals at each designated position to determine whether there is a living body in the target vehicle;

[0073] Step S30: If a living body is detected in the target vehicle, the specific position of the living body is calculated based on the UWB signals at each designated position.

[0074] In detail, the control module controls the rotation module to drive the UWB radar 2 to rotate to each designated position in sequence within a preset rotation range at a preset rotation angle for scanning to detect whether there is a living body in the target vehicle. The control module can also directly control the rotation module to drive the UWB radar 2 to detect living bodies at multiple designated positions. The designated position can be a pre-set position where a living body may exist. For example, the UWB radar 2 is aimed at the seat. The position corresponding to the seat is more likely to have a living body, and other invalid positions such as the roof of the vehicle are omitted for detecting living bodies, saving power consumption. After the UWB radar 2 rotates to the designated position, the control module controls the UWB radar 2 to rotate to receive and transmit signals, and sends a short pulse signal through the UWB radar 2, receives the returned signal and transmits it to the control module to analyze the time delay and intensity of the echo, so as to determine whether there is a living body target in the vehicle. For example, the presence of a living body is determined by identifying the characteristics of the organism such as breathing and heartbeat. After determining the presence of a living body, the control module calculates the specific location of the living body based on the UWB signals at each designated location. Subsequently, the specific living body location information can be displayed through the living body detection system or an early warning can be issued through the built-in voice information of the display device 10. It can also be connected to the user's mobile device to achieve an online early warning, etc.

[0075] In one example, the detection object is detected at a first specified position, the corresponding UWB radar signal is obtained, and the signal characteristics of the UWB radar signal are extracted. Based on the signal characteristics, it can be determined whether there is a living body. When it is determined that there is a living body, it is further rotated to different angles to perform multi-point detection on the living body. During the signal processing process, the specific position information of the detection object can be further determined based on information such as signal strength and phase in different directions.

[0076] Preferably, in this embodiment, the rotating module is arranged on the top inner wall of the target vehicle, which can reduce the shielding of the UWB radar 2 detection signal by the front seats and further expand the detection range. The UWB radar 2 preferably uses a UWB radar 2 with one transmitting antenna and one receiving antenna (one transmitter and one receivers, hereinafter referred to as 1T1R). The UWB chip of 1T1R is relatively mature and has a lower cost than the UWB chip that needs to support one transmitting antenna and multiple receiving antennas, thereby further saving costs.

[0077] In this embodiment, the UWB radar 2 uses a directional antenna instead of an omnidirectional antenna. The omnidirectional antenna is susceptible to interference and is prone to misdetecting living things outside the vehicle, and has low accuracy. In this embodiment, the UWB radar 2 is driven to rotate by a rotating module, so that multi-point detection can be achieved at different angles. Therefore, a directional antenna with more concentrated signals can be used, which improves the signal reception efficiency and accuracy of the UWB radar 2.

[0078] According to the detection method of the embodiment of the present application, a rotating module is used to drive the UWB radar 2 to rotate, so that the UWB radar 2 can perform multi-point detection on the living body from different angles and obtain multiple UWB radar signals. The specific position of the living body can be calculated based on the multiple UWB radar signals, thereby improving the detection accuracy.

[0079] In some embodiments, the plurality of designated positions include a first designated position and a second designated position, and the step S30 of calculating the specific position of the living body according to the UWB signals at each designated position includes:

[0080] Step S32: acquiring first position coordinates of a first designated position, and acquiring a first UWB radar signal at the first designated position;

[0081] Step S34: acquiring the second position coordinates of the second designated position, and acquiring the second UWB radar signal at the second designated position;

[0082] Step S36: calculating a first distance between the first designated position and the living body according to the first UWB radar signal; calculating a second distance between the second designated position and the living body according to the second UWB radar signal; and calculating a third distance between the first designated position and the second designated position;

[0083] Step S38: Obtain the center position coordinates of the rotation axis of the display device 10, and calculate the two-dimensional living body position coordinates based on the first position coordinates, the second position coordinates, the first distance, the second distance and the third distance in the plane formed by the center position coordinates, the first position coordinates and the second position coordinates.

[0084] In detail, in step S32, the first position coordinates of the first specified position are obtained: the coordinates of the radar at the first position, that is, the first specified position, are determined, and this coordinate can be a position in a coordinate system relative to a reference point; the first UWB radar signal at the first specified position is obtained, which can be signal data obtained from the UWB radar 2 at the first specified position.

[0085] In step S34, obtaining the second position coordinates of the second designated position may be to determine the coordinates of the UWB radar 2 at the second position, that is, the second designated position. And obtaining the second UWB radar signal at the second designated position may be to obtain signal data from the UWB radar 2 at the second designated position.

[0086] In step S36, the calculated first distance is the distance between the first designated position calculated based on the first UWB radar signal and the living body, that is, the distance between the first designated position and the living body, which usually involves calculating the distance from the time extension of the signal; and the calculated second distance is the distance between the second designated position and the living body calculated based on the second UWB radar signal; and the calculated third distance is the actual distance between the first designated position and the second designated position, which can be calculated by their coordinates.

[0087] In step S38, the center position coordinates of the rotation axis of the display device 10 are obtained, that is, the center position of the rotation axis of the display device 10 in the coordinate system is determined; in the plane formed by the center position coordinates, the first position coordinates and the second position coordinates, these three points are used as calculation references; and the two-dimensional position coordinates of the living body are calculated, that is, in the determined plane, the first position coordinates, the second position coordinates, the first distance, the second distance and the third distance are combined using the triangulation principle to calculate the two-dimensional position coordinates of the living body. For example, a triangulation positioning algorithm can be used.

[0088] refer to Figure 5 , the center position of the fixed side of the display device 10 is the coordinate of the circle (x0, y0), the width of the display device 10 is the radius r of the circle, and the angle of the display device 10 relative to the horizontal plane during rotation is ɑ, then any point on the circle is (x, y), where x = x0 + r*cos(ɑ*3.14 / 180); y = y0 + r*sin(ɑ*3.14 / 180). The unit of ɑ is degree. In this embodiment, the first designated position ( Figure 5 The first position coordinates of point A in the figure are (x1, y1), and the second specified position ( Figure 5 The second position coordinates of point B in the image are (x2, y2).

[0089] In this embodiment, the 1T1RUWB radar 2 is preferably used, and the time difference (Time Of Flight) between the transmission time of the 1T1RUWB radar 2 and the time when the reflected signal is received can be used to calculate the first designated position and the detection object ( Figure 5 The first distance e between the first designated position and the second designated position) is calculated, and the second distance f between the second designated position and the detection object is calculated: the reflected UWB radar signal received at each designated position is processed, and the flight time difference between it and the transmitted signal is calculated. According to the propagation speed of the UWB radar signal, the distance between the detection object and the UWB radar 2 can be calculated. The third distance d between the first designated position and the second designated position is calculated, d = 2r*sin(θ / 2).

[0090] In a plane formed by the center position coordinates (x0, y0), the first position coordinates (x1, y1) and the second position coordinates (x2, y2), the two-dimensional position coordinates of the detected object point T in the plane are calculated by the Pythagorean theorem of the triangle. In this embodiment, the position can be specified by two test points, or detection can be performed by multiple points to improve the accuracy of position detection.

[0091] refer to Figure 6 , when the detection object T is located between two test points A and B: According to the Pythagorean theorem, the following two equations are obtained: h 2 +l 2 =e 2 ;h 2 +(dl) 2 =f 2 , h is the distance between point T and line AB; according to the above two equations, l and h can be calculated, and the coordinates of point T can be obtained through l and h.

[0092] refer to Figure 7 , in the scenario where the detection object T is located below the two test points A and B (the detection object is located below the UWB radar 2): According to the Pythagorean theorem, the following two equations are obtained: h 2 +(d+l) 2 =e 2 ;h 2 +l 2 =f 2 , h is the distance between point T and line AB; according to the above two equations, l and h can be calculated, and the coordinates of point T can be obtained through l and h.

[0093] refer to Figure 8 , in the scenario where the detection object T is located above the two test points A and B (the detection object is located above UWB radar 2): According to the Pythagorean theorem, the following two equations are obtained: h 2 +(d+l) 2 =f 2 ;h2 +l 2 =e 2 , h is the distance between point T and line AB; according to the above two equations, l and h can be calculated, and the coordinates of point T can be obtained through l and h.

[0094] This embodiment uses a 1T1R UWB radar 2 to obtain the two-dimensional position coordinates of a living body, thereby estimating the up, down, front, and back positions of a living body (such as a passenger's lungs) in the vehicle, and can distinguish whether the passenger is lying or sitting upright, and whether he is in the front or back row of the vehicle.

[0095] According to the above implementation, if it is necessary to further analyze the position coordinates of the living body in the three-dimensional space, an angle value offset on the Z axis is also required, wherein the Z axis is perpendicular to the above test plane. In this regard, in this implementation, the UWB radar includes one transmitting antenna and two receiving antennas, that is, a UWB radar with one transmitting antenna and two receiving antennas (one transmitter and two receivers, hereinafter referred to as 1T2R) is used. After calculating the two-dimensional position coordinates of the living body, the detection method further includes:

[0096] S392, calculating the phase difference between the reflected UWB signals received by the two receiving antennas at any detection position;

[0097] S394, constructing a straight line between the actual position of the living body and the UWB radar, and calculating the angle between the straight line and the plane according to the phase difference;

[0098] S396, calculating the distance between the actual position of the living body and the plane according to the angle;

[0099] S398, using the distance and the two-dimensional living body position coordinates as the three-dimensional living body position coordinates of the detected object.

[0100] The angle of the detected object is calculated by the arrival phase difference between the two receiving antennas. Fig. 9 , construct a straight line between the detection object T2 point and the UWB radar, and calculate the angle β between the straight line and the test plane according to the phase difference. The Z axis is perpendicular to the plane ABT1, and the offset on the Z axis is calculated by the trigonometric sine function. The offset value is also the distance between the actual position of the detection object and the plane (i.e. Fig. 9 The length of the midline segment T1T2), the distance and the two-dimensional living body position coordinates are used as the three-dimensional living body position coordinates of the detected object.

[0101] This embodiment uses a 1T2R UWB radar to obtain the three-dimensional position coordinates of the living body, thereby further estimating the left and right positions of the living body (such as a passenger) in the vehicle, and can distinguish whether the passenger is located on the left or right side of the vehicle.

[0102] In one implementation of this embodiment, detecting whether there is a living body in the target vehicle according to the signal characteristics of the UWB radar signal includes:

[0103] S311, inputting the signal features into a pre-trained model;

[0104] S312, obtaining a prediction result output by the model, wherein the prediction result indicates whether there is a living body in the target vehicle.

[0105] In this embodiment, a deep learning method is used to train the model using the UWB signal for detecting human breathing as a feature to obtain a trained model. The signal features of the UWB signal collected in real time are input into the pre-trained model to predict whether there is a living body. Through the complex structure and automatic feature learning ability of the deep learning model, this embodiment can extract features related to human breathing from subtle changes in the UWB signal, can more comprehensively understand the scene information, significantly improve the accuracy of judging the presence of living bodies, and maintain high robustness even under complex environmental changes or interference conditions.

[0106] In another implementation of this embodiment, after calculating the living body position of the living body, the method further includes: pushing a warning message to a registered client device through a communication link established with the target vehicle; or triggering an external warning mechanism of the target vehicle. In an application scenario of this embodiment, after the target vehicle is parked and locked, the in-vehicle living body detection system is activated to detect the in-vehicle living body of the target vehicle, and the UWB radar is controlled to rotate to a specified position to start working. If a living body (such as a child or a pet) is found to be forgotten in the car, a prompt message is pushed to the client, such as notifying the owner through a phone call and SMS with the owner's registered information, or controlling the target vehicle to light up or honk.

[0107] In another implementation of this embodiment, after calculating the living body position of the living body according to the UWB radar signals at multiple detection positions, the method further includes: extracting the signal frequency change characteristics of the UWB radar signal according to the UWB radar signal, wherein the signal frequency change characteristics represent the breathing frequency of the living body; detecting the sleep state of the living body detection object according to the signal frequency change characteristics; and automatically turning off the display screen when the sleep state is a sleeping state. In one application scenario, passengers in the back row watch videos using a car ceiling screen. The UWB radar chip continuously detects the passenger's breathing state and determines whether the passenger is asleep based on the change in breathing frequency. If the calculation shows that the passenger has fallen asleep, the video on the car ceiling screen is automatically turned off to save power consumption and avoid disturbing the passenger's rest.

[0108] In this embodiment, reference Fig.10The second component block diagram of the in-vehicle living body detection system, the in-vehicle living body detection system includes a UWB radar, a vehicle-mounted ceiling screen, a microcontroller unit MCU (Microcontroller Unit) or a central processing unit CPU (Central Processing Unit), a position sensor, and a vehicle system;

[0109] Among them, the UWB radar includes a UWB chip, a transmitting antenna and a receiving antenna, which are used to transmit and receive UWB signals respectively. UWB signals can provide high-precision distance measurement and positioning, and can detect the presence or absence of living breathing, thereby detecting whether there is a living body. The vehicle-mounted ceiling screen is embedded on the roof of the vehicle, and the UWB radar is embedded at the edge of the display screen. The vehicle-mounted ceiling screen itself has a rotating mechanism, which can accurately control the rotation angle. By rotating to different specific positions for UWB radar detection, the data is summarized and processed to achieve three-dimensional perception of the position in the car. The MCU / CPU controls the rotation of the rotating mechanism, receives position information, receives UWB signals, and uses the position information and UWB reflection signals to calculate whether there is a living body and the position of the living body. The position sensor can be an encoder or a Hall sensor, which is used to return the position of the screen. The car system is used to output video signals, receive UWB calculation results, control the position state of the rotating screen, etc.

[0110] The solution of this embodiment provides a method for detecting living bodies in a vehicle. Fig.11 It is an implementation flow chart of the embodiment of the present application, including:

[0111] In one example, the MCU controls the motor to rotate, and the position sensor returns the position information of the rotating mechanism. When the screen reaches multiple detection angles (such as the rear passenger position) in sequence, it stops rotating. The MCU controls the UWB chip to transmit directional UWB signals respectively to prevent interference from other directions. The UWB RX antenna continuously receives the reflected signal of the UWB and outputs it to the MCU; the MCU calculates the three-dimensional position coordinates of the living body based on the positions and measurement values ​​at multiple measurement points, and then determines whether the living body is in a sleeping state. When the living body is in a sleeping state, corresponding processing is performed, such as controlling the shutdown of the vehicle-mounted ceiling screen.

[0112] This embodiment uses the existing rotating mechanism of the vehicle-mounted ceiling screen to perform multi-point detection, so that the antenna can transmit and receive signals in different directions, thereby improving the signal reception efficiency and accuracy, reducing interference, and saving costs.

[0113] Through the description of the above implementation methods, those skilled in the art can clearly understand that the method according to the above embodiment can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes a number of instructions for a terminal device (which can be a mobile phone, computer, server, or network device, etc.) to execute the methods described in each embodiment of the present application.

[0114] According to an embodiment of the present application, an electronic device includes a processor 402, a communication interface, a memory 404, and a communication bus, wherein the processor 402, the communication interface, and the memory 404 communicate with each other through the communication bus; wherein:

[0115] Memory 404, used for storing computer programs;

[0116] The processor 402 is used to execute the steps in the above detection method by running the program stored in the memory 404.

[0117] The memory 404 can be used to store computer programs, for example, software programs and modules of application software, such as a computer program corresponding to a method for detecting a living body in a vehicle in an embodiment of the present application. The processor 402 executes various functional applications and data processing by running the computer program stored in the memory 404, that is, to implement the above method. The memory 404 may include a high-speed random access memory 404, and may also include a non-volatile memory 404, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory 404. In some examples, the memory 404 may further include a memory 404 remotely arranged relative to the processor 402, and these remote memories 404 may be connected to the computer via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0118] The transmission device 406 is used to receive or send data via a network. The specific example of the above network may include a wireless network provided by a communication provider of the computer. In one example, the transmission device 406 includes a network adapter (Network Interface Controller, referred to as NIC), which can be connected to other network devices through a base station so as to communicate with the Internet. In one example, the transmission device 406 can be a radio frequency (RF) module, which is used to communicate with the Internet wirelessly.

[0119] In some embodiments, the electronic device may further include a transmission device 406 and an input / output device 408 , wherein the transmission device 406 is connected to the processor 402 , and the input / output device 408 is connected to the processor 402 .

[0120] In some embodiments, Fig.12 As shown, the electronic device may include one or more (only one is shown in the figure) processors 402 (the processor 402 may include but is not limited to a processing device such as a microprocessor MCU or a programmable logic device FPGA) and a memory 404 for storing data. In some embodiments, the above-mentioned computer may also include a transmission device 406 and an input and output device 408 for communication functions. It can be understood by those skilled in the art that Fig.12 The structure shown is only for illustration and does not limit the structure of the above electronic device. Fig.12 More or fewer components as shown, or with Fig.12 Different configurations are shown.

[0121] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic, for example, the division of units is only a logical function division, and there may be other division methods in actual implementation, for example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0122] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0123] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0124] The above are only preferred implementations of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A living body detection system, characterized in that: include: Rotation module; A UWB radar, wherein the UWB radar is arranged at an output end of the rotating module; A control module, the control module being electrically connected to the rotation module and the UWB radar; The rotating module drives the UWB radar to rotate to a plurality of designated positions in sequence, and the UWB radar receives and sends UWB radar signals at the plurality of designated positions for multi-point detection, and transmits the UWB radar signals to the control module.

2. The living body detection system according to claim 1, characterized in that: The rotating module comprises a display device and an active mechanism, and the display device is rotatably connected to the active mechanism.

3. The living body detection system according to claim 2, characterized in that: The active mechanism comprises a driving component and a transmission component. The driving component is drivingly connected to the transmission component, and the driving component has a built-in first sensor.

4. The living body detection system according to claim 2, characterized in that: The display device includes a first edge and a second edge, the first edge and the second edge are parallel to the rotation axis of the display device, and the first edge is close to the rotation axis of the display device, and the second edge is far from the rotation axis of the display device, and the UWB radar is arranged at the second edge.

5. The living body detection system according to claim 2, characterized in that: The rotating module further comprises a driven mechanism, the driven mechanism is connected to the display device, and the driven mechanism has a second sensor built therein.

6. The living body detection system according to claim 1, characterized in that: The UWB radar comprises a transmitting antenna and a receiving antenna, and both the transmitting antenna and the receiving antenna are directional antennas.

7. A detection method, for use in a liveness detection system as claimed in any one of claims 1 to 6, characterized in that: The detection method comprises: Control the UWB radar to rotate to multiple specified positions in sequence; Controlling the UWB radar to send and receive UWB radar signals at each of the designated positions to determine whether there is a living body in the target vehicle; If a living body is detected in the target vehicle, the specific position of the living body is calculated according to the UWB signal at each of the designated positions.

8. The detection method according to claim 7, characterized in that: The multiple designated positions include a first designated position and a second designated position, and the calculating the specific position of the living body according to the UWB signal at each of the designated positions includes: Acquire a first position coordinate of the first designated position, and acquire a first UWB radar signal at the first designated position; Acquire the second position coordinates of the second designated position, and acquire the second UWB radar signal at the second designated position; Calculate a first distance between the first designated position and the living body according to the first UWB radar signal; calculate a second distance between the second designated position and the living body according to the second UWB radar signal; and calculate a third distance between the first designated position and the second designated position; The center position coordinates of the rotation axis of the display device are obtained, and in a plane formed by the center position coordinates, the first position coordinates and the second position coordinates, the two-dimensional living body position coordinates are calculated based on the first position coordinates, the second position coordinates, the first distance, the second distance and the third distance.

9. The detection method according to claim 8, characterized in that: The UWB radar includes a transmitting antenna and two receiving antennas. After calculating the two-dimensional living body position coordinates of the living body, the detection method further includes: Calculating the phase difference between the UWB radar signals received by the two receiving antennas at any detection position; Constructing a straight line between the actual position of the living body and the UWB radar, and calculating an angle between the straight line and the plane according to the phase difference; Calculating the distance between the actual position of the living body and the plane according to the angle; The distance and the two-dimensional living body position coordinates are used as the three-dimensional living body position coordinates of the detected object.

10. An electronic device, characterized in that: It includes a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory communicate with each other through the communication bus; wherein: Memory, used to store computer programs; A processor, configured to execute the detection method according to any one of claims 7 to 9 by running a program stored in a memory.

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