A PIR-based motion detection method, system and medium

Abstract

The present application proposes a PIR-based motion detection method, including: S1, interval sampling to obtain the target PIR signal in the detection area; S2, performing motion feature point calculation on the target PIR signal to obtain the peak value and period of the target PIR signal; S3, in response to when the current sampling point is a zero-crossing point, calculating the average signal amplitude of all the target PIR signals in the same signal half cycle before the current sampling point; S4, in response to when the peak value, the period and the average signal amplitude in the target PIR signal are greater than the corresponding preset threshold at the same time, it is judged that there is human movement in the detection area. The present application specifically improves the accuracy of PIR motion detection and has the effect of lower hardware cost.

Description

Technical Field

[0001] The present application relates to the technical field of motion detection, and in particular to a PIR-based motion detection method, system and medium. Background Art

[0002] Traditional PIR (pyroelectric infrared sensor) motion detection uses thresholds and signal cycles to detect whether a person is passing through. This detection technology has problems such as high false alarm rate, and requires temperature elements to compensate and adjust the threshold, as well as vibration detection through external lines. Not only is the amount of calculation large, but the hardware cost is also high.

[0003] Therefore, it is particularly important to provide a motion detection method with high detection accuracy and greatly reduced hardware costs. Summary of the invention

[0004] In order to solve the technical problems of low accuracy and high cost of PIR motion detection in the prior art, the present application proposes a PIR-based motion detection method, system and medium.

[0005] According to the first aspect of the present application, a PIR-based motion detection method is proposed, comprising:

[0006] S1, interval sampling to obtain the target PIR signal within the detection area;

[0007] S2, performing a moving feature point operation on the target PIR signal to obtain a peak value and a period of the target PIR signal;

[0008] S3, in response to when the current sampling point is a zero-crossing point, calculating the average signal amplitude of all the target PIR signals that are in the same signal half cycle before the current sampling point; and

[0009] S4. In response to the peak value, the period and the average signal amplitude in the target PIR signal being greater than corresponding preset thresholds at the same time, it is determined that there is human movement in the detection area.

[0010] Through the above technical solution, the target PIR signal in the detection area is discretely sampled, and the target PIR signal that is continuously sampled within the same signal half cycle is operated for moving feature points to obtain the peak value, period, and average signal amplitude of the target PIR signal. Then, the target PIR signal is judged to be a mobile signal by threshold comparison, thereby detecting whether there is human movement in the detection area. This application can detect mobile signals more accurately by discretely sampling the target PIR signal and analyzing multiple feature points. At the same time, the amount of calculation is small, and no external components and circuits are required for auxiliary detection, which greatly reduces the hardware cost.

[0011] Preferably, the detection area is divided into at least one group of adjacent positive half-cycle signal areas and negative half-cycle signal areas. When the peak value, the period and the average signal amplitude of the target PIR signal in the positive half-cycle signal area or the negative half-cycle signal area obtained by sampling are simultaneously greater than the corresponding preset thresholds, it is judged that there is human movement in the corresponding signal area.

[0012] Through the above technical solution, the detection area is divided into multiple positive half-cycle signal areas and negative half-cycle signal areas. When the target PIR signal sampled from one of the signal areas meets the conditions of the mobile signal, it is determined that there is human movement in the corresponding signal area.

[0013] Preferably, the step S4 further comprises: when the movement of people in two different signal areas is continuously detected and the time interval is less than the corresponding preset threshold, it is determined that there is a human intrusion in the detection area.

[0014] Through the above technical solution, when it is detected that the target PIR signal in one of the signal areas constitutes a mobile signal, it is possible that a person is wandering in the signal area. When it is detected that the target PIR signals in two consecutive signal areas both constitute mobile signals, it means that a person is moving continuously in the detection area, and human intrusion can be judged at this time.

[0015] Preferably, the step S2 further comprises: the step S2 further comprises: performing vibration characteristic point operation on the target PIR signal to obtain the maximum signal change rate of the target PIR signal;

[0016] The step S4 further includes: when the maximum signal change rate of the target PIR signal is greater than a corresponding preset threshold, determining that vibration occurs in the detection area.

[0017] Through the above technical solution, the maximum signal change rate of the target PIR signal is calculated, and then the mobile signal and the vibration signal are distinguished by threshold comparison, thereby avoiding misjudgment.

[0018] Preferably, in the step S2, before the feature point calculation, the target PIR signal is subjected to low-pass filtering.

[0019] Through the above technical solution, high-frequency signals and low-frequency signals are isolated through low-pass filtering, so that movement signals and vibration signals can be effectively separated to facilitate the discrimination of vibration and personnel movement.

[0020] Preferably, the step S1 specifically includes:

[0021] S11, interval sampling to obtain the original PIR signal in the detection area;

[0022] S12, amplifying the original PIR signal;

[0023] S13, converting the amplified original PIR signal into a digital signal to obtain the target PIR signal.

[0024] Through the above technical solution, since the voltage value of the original PIR signal is small, it is difficult to observe the fluctuation of the signal. Therefore, the original PIR signal is amplified and converted into a digital signal, which is convenient for identification.

[0025] Preferably, the sampling interval of the target PIR signal is 1 ms, the preset threshold corresponding to the time interval is 60 ms, and the preset thresholds corresponding to the peak value, the period and the average signal amplitude of the target PIR signal are 150, 30 ms and 100 respectively.

[0026] Preferably, the preset threshold corresponding to the maximum signal change rate of the target PIR signal is 400.

[0027] According to the second aspect of the present application, a PIR-based motion detection system is proposed, comprising:

[0028] A signal sampling module is configured to obtain the original PIR signal in the detection area through interval sampling and amplify it;

[0029] A processor unit is configured to convert the amplified original PIR signal into a digital signal to obtain a target PIR signal, perform a moving feature point operation on the target PIR signal to obtain a peak value and a period of the target PIR signal, and in response to when the current sampling point is a zero-crossing point, calculate an average signal amplitude of all the target PIR signals that are in the same signal half cycle before the current sampling point;

[0030] The judgment unit is configured to judge that there is human movement in the detection area in response to the peak value, the period and the average signal amplitude in the target PIR signal being greater than corresponding preset thresholds at the same time.

[0031] Preferably, the signal sampling module includes:

[0032] A division unit configured to divide the detection area into at least one group of adjacent positive half-cycle signal areas and negative half-cycle signal areas;

[0033] A PIR unit is configured to obtain an original PIR signal in the positive half-cycle signal area or the negative half-cycle signal area;

[0034] The signal amplifying unit is configured to amplify the original PIR signal.

[0035] According to a third aspect of the present application, a computer-readable storage medium is provided, which stores a computer program. When the computer program is executed by a processor, the PIR-based motion detection method as described in the first aspect of the present application is implemented.

[0036] The present application proposes a PIR-based motion detection method, system and medium, which divide the detection area into adjacent positive half-cycle signal areas and negative half-cycle signal areas, discretely sample the target PIR signal in the detection area, and simultaneously perform motion feature point calculation and vibration feature point calculation on the continuously sampled target PIR signal in the same signal area, and respectively calculate the peak value, period, average signal amplitude and maximum signal change rate of the target PIR signal, and then judge whether the target PIR signal is a motion signal or a vibration signal by threshold comparison. When the motion signal is continuously detected in two different signal areas and the time interval is less than the preset threshold, it means that a person is continuously moving in the positive half-cycle signal area and the negative half-cycle signal area, and it is judged that a person intrusion occurs at this time. The present application separates low-frequency signals and high-frequency signals through low-pass filtering to facilitate the discrimination of mobile signals and vibration signals. The mobile signal is obtained by calculating multiple feature points of the target PIR signal through feature points and performing analysis and judgment. It has high detection accuracy and small calculation amount. The vibration signal is obtained by calculating the maximum signal change rate of the target PIR signal through vibration feature points and performing analysis and judgment. It has high detection accuracy and does not require external lines for auxiliary detection, which greatly reduces hardware costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The accompanying drawings are included to provide a further understanding of the embodiments and are incorporated into and constitute a part of this specification. The accompanying drawings illustrate the embodiments and are used together with the description to explain the principles of the present application. It will be easy to recognize other embodiments and many expected advantages of the embodiments because they become better understood by reference to the following detailed description. The elements of the drawings are not necessarily to scale with each other. The same reference numerals refer to corresponding similar parts.

[0038] Figure 1 is a flow chart of a PIR-based motion detection method according to an embodiment of the present application;

[0039] Figure 2 is a flow chart of a PIR-based motion detection method according to a specific embodiment of the present application;

[0040] Figure 3 is a block diagram of a PIR-based motion detection system according to an embodiment of the present application;

[0041] Figure 4is a test result diagram when a person moves to the left at a distance of 6m from the motion detection system according to a specific embodiment of the present application;

[0042] Figure 5 4 is a diagram of vibration test results within a detection area according to a specific embodiment of the present application.

[0043] Explanation of the accompanying drawings: 1. signal acquisition module; 11. division unit; 12. PIR unit; 13. signal amplification unit; 2. processor unit; 3. judgment unit; ①. first positive half-cycle signal area; ②. first negative half-cycle signal area; ③. second negative half-cycle signal area; ④. second positive half-cycle signal area; ⑤. third negative half-cycle signal area; ⑥. third positive half-cycle signal area; ⑦. fourth negative half-cycle signal area; T1. first time interval; T2. second time interval. DETAILED DESCRIPTION

[0044] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and Examples. It should be understood that the specific embodiments described herein are only configured to explain the present application and are not configured to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present application by illustrating the examples of the present application.

[0045] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0046] According to the first aspect of the present application, a motion detection method based on PIR is proposed.

[0047] Figure 1 FIG. 4 shows a flow chart of a PIR-based motion detection method according to an embodiment of the present application, as shown in FIG. Figure 1 As shown, the motion detection method includes the following steps:

[0048] S1. Interval sampling to obtain the target PIR signal in the detection area.

[0049] In a specific embodiment, since the voltage value of the original PIR signal directly sampled in the detection area is small, it is difficult to observe the fluctuation of the signal. Therefore, it is necessary to preprocess the original PIR signal to obtain the target PIR signal. The preprocessing steps specifically include:

[0050] S11, interval sampling to obtain the original PIR signal in the detection area;

[0051] S12, amplifying the original PIR signal;

[0052] S13, converting the amplified original PIR signal into a digital signal to obtain a target PIR signal.

[0053] In a specific embodiment, the detection area is divided into a group of adjacent positive half-cycle signal areas and negative half-cycle signal areas, and the target PIR signal of the detection area is sampled every 1ms. When there is no movement of personnel or vibration of objects in the detection area, the sampled target PIR signal is the PIR signal reference value. In this embodiment, the PIR signal reference value is specifically 1870; when the value of the sampled target PIR signal is greater than the PIR signal reference value 1870, it means that there is movement of personnel or vibration of objects in the detection area, and the signal comes from the positive half-cycle signal area, that is, the target PIR signal is a positive half-cycle signal; when the value of the target PIR signal is less than the PIR signal reference value 1870, it means that there is movement of personnel or vibration of objects in the detection area, and the signal comes from the negative half-cycle signal area, that is, the target PIR signal is a negative half-cycle signal.

[0054] It should be appreciated that in other implementations, the detection area may also be divided into a plurality of adjacent groups of positive half-cycle signal areas and negative half-cycle signal areas.

[0055] S2. Perform moving feature point operation on the target PIR signal to obtain the peak value and period of the target PIR signal.

[0056] Figure 2 FIG. 4 shows a flow chart of a PIR-based motion detection method according to a specific embodiment of the present application, as shown in FIG. Figure 2 As shown, in a specific embodiment, step S2 specifically includes:

[0057] After step S1, execute:

[0058] S21a, performing low-pass filtering on the target PIR signal.

[0059] In a specific embodiment, the target PIR signal is low-pass filtered by a 3rd-order or higher FIR filter to exclude high-frequency signals, thereby effectively separating the vibration signal and the motion signal to facilitate subsequent object vibration identification and personnel motion detection.

[0060] S22a, performing a moving feature point operation on the target PIR signal to calculate the peak value, period and signal amplitude of the target PIR signal.

[0061] Among them, the definitions of multiple feature points of the target PIR signal are as follows:

[0062] Peak value: Assuming the maximum value of the positive half-cycle signal is A and the PIR signal reference value is B, the peak value is expressed as "AB". Assuming the minimum value of the negative half-cycle signal is C, the peak value is expressed as "BC".

[0063] Period: The cumulative calculation of sampling time in the same signal area, that is, the duration of a half-cycle signal.

[0064] Signal amplitude: The fluctuation of the target PIR signal relative to the PIR signal reference value, that is, the absolute value of the difference between the target PIR signal and the PIR signal reference value.

[0065] Continue to refer to Figure 2 In a preferred embodiment, step S2 further includes: performing vibration feature point calculation on the target PIR signal to calculate the maximum signal change rate of the target PIR signal. The vibration feature point calculation specifically includes:

[0066] After step S1, while executing step S21a, execute:

[0067] S21b, calculating the signal slope of the target PIR signal.

[0068] The signal slope is calculated as:

[0069] ΔADC / Δt

[0070] Among them, ΔADC represents the absolute value of the difference between the target PIR signal corresponding to the two sampling points before and after, and Δt represents the sampling interval, that is, 1ms. By calculating the signal slope of the target PIR signal by differential operation, the change of the target PIR signal can be intuitively reflected.

[0071] S22b, performing an absolute value operation on the signal slope to obtain a signal change rate, and obtaining a maximum signal change rate among all target PIR signals in the same signal area.

[0072] By calculating the maximum signal change rate of the target PIR signal, the vibration characteristics of the target PIR signal can be reflected, thereby facilitating the subsequent determination of whether the target PIR signal is a vibration signal.

[0073] Continue to refer to Figure 1 , after step S2, execute:

[0074] S3. In response to the current sampling point being a zero-crossing point, calculate the average signal amplitude of all target PIR signals that are within the same signal half cycle before the current sampling point.

[0075] Continue to refer to Figure 2 In a specific embodiment, step S3 specifically includes:

[0076] After steps S22a and S22b, execute:

[0077] S31, determine whether the current sampling point is the zero-crossing point of the positive half-cycle signal and the negative half-cycle signal, if so, execute step S32, if not, return to step S1.

[0078] Assuming that the target PIR signal corresponding to the previous sampling point is a positive half-cycle signal, and the target PIR signal corresponding to the current sampling point is a negative half-cycle signal, it means that the current sampling point is the zero-crossing point of the positive half-cycle signal and the negative half-cycle signal.

[0079] S32, calculating the average signal amplitude of all target PIR signals in the same signal area before the zero crossing point.

[0080] As the detection cycle proceeds, this step is used to calculate the average signal amplitude of all target PIR signals within a signal half cycle.

[0081] Continue to refer to Figure 1 , after step S3, execute:

[0082] S4. In response to the fact that the peak value, period and average signal amplitude in the target PIR signal are simultaneously greater than the corresponding preset thresholds, it is determined that there is human movement in the detection area.

[0083] Continue to refer to Figure 2 In a specific embodiment, step S4 specifically includes:

[0084] S41, determine whether the maximum signal change rate of the target PIR signal is greater than the corresponding preset threshold, if so, execute step S42, if not, execute step S43.

[0085] S42, issue a vibration alarm and start the alarm timer, and return to step S1.

[0086] The maximum signal change rate of the target PIR signal reflects the vibration characteristic value of the target PIR signal. When the vibration characteristic value of the target PIR signal exceeds the corresponding preset threshold, the target PIR signal has constituted a vibration signal. At this time, it can be determined that vibration has occurred in the signal area where the target PIR signal is located. In this embodiment, the preset threshold corresponding to the maximum signal change rate is set to 600. When it is determined that vibration occurs in the detection area, the corresponding zero-crossing alarm output state PIR status = 0xFF; the alarm timing duration is 6s, that is, the alarm stops automatically after 6s of the alarm.

[0087] S43, determine whether the peak value, period and average signal amplitude in the target PIR signal are simultaneously greater than the corresponding preset thresholds, if so, execute step S44, if not, return to step S1.

[0088] By analyzing the multiple feature points obtained after the mobile feature point calculation, when the multiple feature points are all greater than the corresponding preset thresholds, it can be determined that the target PIR signal is a mobile signal generated by the movement of personnel. In this embodiment, the preset threshold corresponding to the peak value is 150, that is, the detected positive half-cycle signal must be greater than 2020 or the negative half-cycle signal must be less than 1720; the preset threshold corresponding to the period is 30ms, that is, the duration of the detected positive half-cycle signal or negative half-cycle signal must be greater than 30ms; the preset threshold corresponding to the average signal amplitude is 100.

[0089] S44, determine whether there is human movement in the signal area where the target PIR signal is located, and continue to determine whether human movement is detected continuously in two different signal areas and the time interval is less than the corresponding preset threshold. If so, execute step S45, if not, return to step S1.

[0090] S45: Determine if there is human intrusion, issue a human intrusion alarm and return to step S1.

[0091] When it is detected that there is movement of a person in one of the signal areas, that is, the target PIR signal is a moving signal, it is possible that the person is wandering in the signal area. When it is detected that the target PIR signals in two consecutive different signal areas are both moving signals, and the time interval is within the corresponding preset threshold, it means that the person is moving continuously in the detection area, and then it can be judged that the person has invaded. In this embodiment, the preset threshold corresponding to the time interval is set to 60ms. When it is judged that there is movement of a person in the positive half-cycle signal area, the corresponding zero-crossing alarm output state PIR status=1; when it is judged that there is movement of a person in the negative half-cycle signal area, the corresponding zero-crossing alarm output state PIR status=2; when it is judged that there is invasion of the detection area, the corresponding zero-crossing alarm output state PIR status=3.

[0092] According to a second aspect of the present application, based on the above-mentioned PIR-based motion detection method, a PIR-based motion detection system is proposed.

[0093] Figure 3 FIG. 4 shows a block diagram of a PIR-based motion detection system according to an embodiment of the present application, as shown in FIG. Figure 3 As shown, the system includes:

[0094] The signal sampling module 1 is configured to obtain the original PIR signal in the detection area through interval sampling and amplify the signal;

[0095] The signal processing unit 2 is configured to convert the amplified original PIR signal into a digital signal to obtain a target PIR signal, perform a moving feature point operation on the target PIR signal to obtain a peak value and a period of the target PIR signal, and in response to when the current sampling point is a zero crossing point, calculate the average signal amplitude of all target PIR signals that are in the same signal half cycle before the current sampling point;

[0096] The judgment unit 3 is configured to judge that there is human movement in the detection area in response to the peak value, period and average signal amplitude in the target PIR signal being greater than the corresponding preset thresholds at the same time.

[0097] Among them, the signal sampling module specifically includes:

[0098] A division unit 11 is configured to divide the detection area into at least one group of adjacent positive half-cycle signal areas and negative half-cycle signal areas;

[0099] The PIR unit 12 is configured to obtain an original PIR signal in a positive half-cycle signal area or a negative half-cycle signal area;

[0100] The signal amplifying unit 13 is configured to amplify the original PIR signal.

[0101] In a specific embodiment, the dividing unit 11 is a Fresnel lens, the PIR unit 12 is a PIR element, the signal amplifying unit 13 is a signal amplifier, the signal processing unit 2 is an analog-to-digital converter (ADC), and the judging unit 3 can be a personal computer or a single-chip microcomputer with an alarm. The detection area is divided into adjacent positive half-cycle signal areas and negative half-cycle signal areas by using a Fresnel lens. The adjacent positive half-cycle signal areas and negative half-cycle signal areas are respectively irradiated to the elements of different polarities in the PIR element. When a person or an object moves or vibrates in the adjacent positive half-cycle signal areas and negative half-cycle signal areas, the elements of different polarities in the PIR element will produce corresponding polarity changes, that is, positive half-cycle signals and negative half-cycle signals are respectively generated.

[0102] Figure 4FIG. 4 shows a test result diagram of a person moving to the left at a distance of 6 m from the motion detection system according to a specific embodiment of the present application. Figure 4 As shown, in the first positive half-cycle signal area ①, the peak value of the positive half-cycle signal (i.e., the target PIR signal) is 182, the period is 93ms, the average signal amplitude is 113, and the maximum signal change rate is 55. Therefore, the positive half-cycle signal meets the conditions for constituting a mobile signal, and the corresponding zero-crossing alarm output state PIR status=1. In the first negative half-cycle signal area ②, the peak value of the negative half-cycle signal (i.e., the target PIR signal) is 400, the period is 244ms, the average signal amplitude is 193, and the maximum signal change rate is 63. Therefore, the negative half-cycle signal meets the conditions for constituting a mobile signal, and the first time interval T1 between the adjacent first positive half-cycle signal area ① and the first negative half-cycle signal area ② is 33ms, which is less than the preset threshold value of the time interval of 60ms, so the conditions for constituting a human intrusion are met, and the corresponding zero-crossing alarm output state PIR status=3. In the second negative half-cycle signal area ③, the peak value of the negative half-cycle signal is 274, the period is 107ms, the average signal amplitude is 166, and the maximum signal change rate is 57. Therefore, the negative half-cycle signal meets the conditions for constituting a mobile signal, and the corresponding zero-crossing alarm output state PIR status = 2. In the second positive half-cycle signal area ④, the peak value of the positive half-cycle signal is 429, the period is 288ms, the average signal amplitude is 201, and the maximum signal change rate is 61. Therefore, the positive half-cycle signal meets the conditions for constituting a mobile signal, and the second time interval T2 between the adjacent second negative half-cycle signal area ③ and the second positive half-cycle signal area ④ is 50ms, which is less than the preset threshold value of the time interval of 60ms, so it meets the conditions for constituting a human intrusion, and the corresponding zero-crossing alarm output state PIR status = 3.

[0103] Figure 5 FIG. 4 shows a vibration test result diagram within a detection area according to a specific embodiment of the present application. Figure 5 As shown, in the third negative half-cycle signal area ⑤, the maximum signal change rate of the negative half-cycle signal reaches 623, which is greater than the third preset threshold value 600. Therefore, the negative half-cycle signal meets the conditions for constituting a vibration signal, while in the third positive half-cycle signal area ⑥, the maximum signal change rate of the positive half-cycle signal is 87, and in the fourth negative half-cycle signal area ⑦, the maximum signal change rate of the negative half-cycle signal is 62, both of which do not meet the conditions for constituting a vibration signal. Therefore, the vibration alarm only lasts for 6 seconds and then ends automatically, that is, the corresponding zero-crossing alarm output state PIR status = 0xFF lasts for 6 seconds.

[0104] According to a third aspect of the present application, a computer-readable storage medium is provided, which stores a computer program. When the computer program is executed by a processor, the PIR-based motion detection method according to the first aspect of the present application is implemented.

[0105] The present application proposes a PIR-based motion detection method, system and medium, which divides the detection area into adjacent positive half-cycle signal areas and negative half-cycle signal areas, performs discrete sampling on the target PIR signal in the detection area, and performs motion feature point calculation and vibration feature point calculation on the continuously sampled target PIR signal in the same signal area, respectively calculating the peak value, period, average signal amplitude and maximum signal change rate of the target PIR signal, and then judges whether the target PIR signal is a motion signal or a vibration signal by comparing with a preset threshold, thereby distinguishing between human movement and object vibration. When a motion signal is detected in two different signal areas continuously, and the time interval is less than the preset threshold, it means that a person is moving continuously in the positive half-cycle signal area and the negative half-cycle signal area, and it is judged that this constitutes a human intrusion. The present application separates low-frequency signals and high-frequency signals through low-pass filtering to facilitate the discrimination of mobile signals and vibration signals. The mobile signal is obtained by calculating multiple feature points of the target PIR signal through mobile feature points and performing analysis and judgment. It has high detection accuracy and small calculation amount. The vibration signal is obtained by calculating the maximum signal change rate of the target PIR signal through vibration feature points and performing analysis and judgment. It has high detection accuracy and does not require external lines for auxiliary detection, which greatly reduces hardware costs.

[0106] In the embodiments of the present application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device / system / method embodiments described above are only schematic. For example, the division of the units can be a logical function division. 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.

[0107] 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 units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0108] 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.

[0109] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, disk or optical disk and other media that can store program codes.

[0110] Obviously, those skilled in the art can make various modifications and changes to the embodiments of the present application without departing from the spirit and scope of the present application. In this way, if these modifications and changes are within the scope of the claims of the present application and their equivalents, the present application is also intended to cover these modifications and changes. The word "comprising" does not exclude the presence of other elements or steps not listed in the claims. The simple fact that certain measures are recorded in mutually different dependent claims does not indicate that the combination of these measures cannot be used to profit. Any figure mark in the claims should not be considered to limit the scope.

Claims

1. A motion detection method based on PIR, characterized in that: include: S1, interval sampling to obtain the target PIR signal within the detection area; S2, performing a moving feature point operation on the target PIR signal to obtain a peak value and a period of the target PIR signal; and also comprising performing a vibration feature point operation on the target PIR signal to obtain a maximum signal change rate of the target PIR signal; S3, in response to when the current sampling point is a zero-crossing point, calculating the average signal amplitude of all the target PIR signals that are in the same signal half cycle before the current sampling point; as well as S4, in response to the peak value, the period and the average value in the target PIR signal When the signal amplitudes are greater than the corresponding preset thresholds at the same time, it is judged that there is human movement in the detection area; and when the maximum signal change rate of the target PIR signal is greater than the corresponding preset threshold, it is judged that vibration occurs in the detection area.

2. The PIR-based motion detection method according to claim 1, characterized in that: The detection area is divided into at least one group of adjacent positive half-cycle signal areas and negative half-cycle signal areas, When the target in the positive half-cycle signal area or the negative half-cycle signal area is sampled The peak value, the period and the average signal amplitude of the PIR signal are all greater than the corresponding preset thresholds. When the value is set, it is judged that there is movement of people in the corresponding signal area.

3. The PIR-based motion detection method according to claim 2, characterized in that: The step S4 also includes: when it is continuously detected that there is human movement in two different signal areas and the time interval is less than the corresponding preset threshold, it is determined that there is human intrusion in the detection area.

4. The PIR-based motion detection method according to claim 1, characterized in that: In the step S2, before the feature point calculation, the target PIR signal is subjected to low-pass filtering.

5. The PIR-based motion detection method according to claim 3, characterized in that: The step S1 specifically includes: S11, interval sampling to obtain the original PIR signal in the detection area; S12, amplifying the original PIR signal; S13, converting the amplified original PIR signal into a digital signal to obtain the target PIR signal.

6. The PIR-based motion detection method according to claim 5, characterized in that: The sampling interval of the target PIR signal is 1 ms, the preset threshold corresponding to the time interval is 60 ms, and the preset thresholds corresponding to the peak value, the period and the average signal amplitude of the target PIR signal are 150, 30 ms and 100 respectively.

7. The PIR-based motion detection method according to claim 1, characterized in that: The preset threshold corresponding to the maximum signal change rate of the target PIR signal is 400.

8. A PIR-based motion detection system, characterized in that: include: A signal sampling module is configured to obtain the original PIR signal in the detection area through interval sampling and amplify it; The processor unit is configured to convert the amplified original PIR signal into a digital signal to obtain a target PIR signal, perform a moving feature point operation on the target PIR signal to obtain a peak value and a period of the target PIR signal, perform a vibration feature point operation on the target PIR signal to obtain a maximum signal change rate of the target PIR signal; in response to when the current sampling point is a zero-crossing point, calculate the average signal amplitude of all the target PIR signals that are in the same signal half cycle before the current sampling point; The judgment unit is configured to judge that there is human movement in the detection area in response to when the peak value, the period and the average signal amplitude in the target PIR signal are simultaneously greater than the corresponding preset thresholds; when the maximum signal change rate of the target PIR signal is greater than the corresponding preset threshold, it is judged that vibration occurs in the detection area.

9. The PIR-based motion detection system according to claim 8, characterized in that: The signal sampling module comprises: A dividing unit configured to divide the detection area into at least one group of adjacent positive half-cycle signal areas and negative half-cycle signal areas; A PIR unit is configured to obtain an original PIR signal in the positive half-cycle signal area or the negative half-cycle signal area; The signal amplifying unit is configured to amplify the original PIR signal.

10. A computer-readable storage medium storing a computer program, wherein the computer program implements the method according to any one of claims 1 to 7 when executed by a processor.

Images