In-vehicle Moving Target Detection Method and Device

Abstract

A method and device for detecting moving targets inside a vehicle. The method includes: collecting environmental interference signals; determining whether the number of times the amplitude of the environmental interference signals exceeds a preset interference signal threshold is greater than a total number threshold. If so, clear the alarm. Otherwise, collect the first ultrasonic echo signal, and then after repeating the steps of collecting environmental interference signals and determining whether the number of times the amplitude of the environmental interference signals exceeds the preset interference signal threshold, collect the second ultrasonic echo signal; calculate the absolute difference between the amplitude of each ultrasonic signal in the first ultrasonic echo signal and the ultrasonic signal collected at the corresponding moment in the second ultrasonic echo signal; accumulate all the absolute differences to form a total absolute difference sum; and determine whether the total number of times the total absolute difference sum is greater than the current alarm threshold is not less than the alarm number threshold. If so, determine that there is a moving target inside the vehicle. Otherwise, clear the alarm.

Description

Technical Field

[0001] The present invention relates to the technical field of automobile parking safety, and in particular to a method and device for detecting a moving target in a vehicle. Background Art

[0002] With the continuous increase in the number of passenger cars in the world, cars have become the main means of transportation for most residents. While car travel brings convenience to users, it also inevitably brings about the personal or property safety of passengers.

[0003] For example, after the car is parked, due to negligence, children or pets may be left in the car, and they cannot get out of the car or keep ventilation because the doors and windows are sealed. Especially in summer, due to the high outdoor temperature, the car is exposed to the sun and the temperature inside the car rises rapidly. In this way, children or pets in the car die from high temperature, lack of oxygen and dehydration due to long-term high temperature environment. For another example, after the car is parked, valuables are placed in the car, and criminals use tools to knock on the door or break the glass to steal valuables in the car, which may also cause significant property losses to car users.

[0004] At present, there are many types of technical means on the market that use different principles to solve the problem of children or pets being trapped in cars and dying, or vehicles being smashed and stolen. However, these existing technologies all have obvious technical defects. For example, some technologies use pressure sensors set on the seats to detect whether a person is in the seat. However, when a heavy object is placed on the seat, it is difficult to distinguish whether the detected person is a person or an object. Some technologies use the phenomenon of human thermal radiation to detect the human body. However, when the temperature in the car is close to the human body temperature, it is also difficult to distinguish whether it is the human body or the seat that is hot, and it is easy to make a wrong judgment. Some technologies use the principle of sound detection, which is based on the principle that people will shout after being trapped. However, this poses a risk of privacy leakage, and there is also the problem of interference from sound sources outside the car. Other existing technologies use cameras to perform image recognition on the human body, which also poses a great risk of privacy leakage.

[0005] In addition, the prior art mostly uses the ultrasonic detection principle to detect moving targets in the car (such as passengers in the car or illegal elements invading from outside). However, the ultrasonic signal emission and reception in the prior art are based on fixed preset values ​​as the judgment basis. The system compares the waveforms of the two ultrasonic echoes received before and after the ultrasonic wave. When the total difference between the two does not exceed the above fixed preset value, it is considered that there is no moving target in the car, otherwise it is considered that there is a moving target in the car. However, when the environment in the car or the surrounding environment changes, such as when more items are placed in the car or clothes and decorations are hung in the car, the system is prone to false alarms because the waveform amplitude of the ultrasonic echo received by the ultrasonic wave changes greatly compared to the ultrasonic echo received by the environment before the change.

[0006] Therefore, it is necessary to provide an improved method and device for detecting moving objects in a vehicle to eliminate or weaken the adverse effects of changes in the vehicle or the surrounding environment on the detection process and avoid false alarms. Summary of the Invention

[0007] The object of the present invention is to solve the above problems and provide a method for detecting moving objects in a vehicle.

[0008] To meet the object of the present invention, the following technical solutions are adopted:

[0009] A method for detecting moving objects in a vehicle includes:

[0010] Collecting environmental interference signals;

[0011] Judging whether the number of times the amplitude of the environmental interference signal exceeds a preset interference signal threshold is greater than a total number threshold. If so, clearing the alarm; otherwise, performing the following steps;

[0012] Collecting a first ultrasonic echo signal, and then, after performing the steps of collecting the environmental interference signal again and judging whether the number of times the amplitude of the environmental interference signal exceeds the preset interference signal threshold is greater than the total number threshold again, collecting a second ultrasonic echo signal;

[0013] Calculating the absolute difference between the amplitude of each ultrasonic signal of the first ultrasonic echo signal and the amplitude of the ultrasonic signal collected at the corresponding moment of the second ultrasonic echo signal;

[0014] Accumulating all the absolute differences to form a total absolute difference; and

[0015] Judging whether the total number of times the total absolute difference is greater than the current alarm threshold is not less than the alarm number threshold. If so, determining that there is a moving object in the vehicle; otherwise, clearing the alarm.

[0016] According to an embodiment of the present invention, the clearing of the alarm means canceling or pausing the alarm signal indicating the presence of a moving object in the vehicle to the user, which may include but is not limited to canceling or pausing the emission of a sound alarm signal, a light flashing alarm signal, etc., so as to avoid false alarms and thus cause unnecessary panic and tension to the user.

[0017] When the number of times the amplitude of the environmental interference signal exceeds the preset interference signal threshold is less than the total number threshold, it means that the current vehicle environment tends to be stable (the environmental change is very small). At this time, the acquisition process of the ultrasonic echo signal is started.

[0018] In one embodiment, preferably, in the step of collecting ultrasonic echo signals, the collection of the first ultrasonic echo signal includes: an ultrasonic transmitter emitting a first pulse signal; and an ultrasonic receiver receiving the first ultrasonic echo signal formed after reflection of the first pulse signal. The collection of the second ultrasonic echo signal includes: an ultrasonic transmitter emitting a second pulse signal; and an ultrasonic receiver receiving the second ultrasonic echo signal formed after reflection of the second pulse signal.

[0019] Preferably, in one embodiment, after accumulating all the absolute differences to form a total absolute difference sum, and before determining whether the total number of times the total absolute difference sum in a period of time is greater than the current alarm threshold is not less than the alarm times threshold, it further includes: calculating the current alarm threshold based on the minimum calibrated alarm threshold. The calculation of the current alarm threshold based on the minimum calibrated alarm threshold includes: when the sum of the amplitudes of all the collected second ultrasonic echo signals is not greater than 300000, setting the minimum calibrated threshold as the current alarm threshold; otherwise, the current alarm threshold = the minimum calibrated threshold + (the total absolute difference sum - 300000) / R, where R is the change amount threshold coefficient. Further preferably, the value range of the change amount threshold coefficient R is 10 to 50.

[0020] When the environmental interference signal is weak, it can be considered that the influence of this signal on the detection of moving targets is very small. Therefore, the minimum calibrated threshold can be used as the critical value to determine whether there is a moving target in the vehicle. When the environmental interference signal is slightly stronger, although it has an interference effect, this interference effect still satisfies the negative determination result in step 104 above. However, at this time, it is necessary to appropriately increase the value of the above current alarm threshold, and the specific degree of increase is determined according to the above formula (the current alarm threshold = the minimum calibrated threshold + (the total absolute difference sum - 300000) / R) to eliminate the adverse effect of the environmental interference signal and avoid false alarms.

[0021] Preferably, after determining whether the total number of times the total absolute difference sum in a period of time is greater than the current alarm threshold is not less than the alarm times threshold, it further includes: reminding the user that there is a moving target in the vehicle. This is because when it is determined that there is a moving target in the vehicle, only the system obtains this result, but the user does not know. Therefore, it is necessary to warn the user of the same information through appropriate means such as sound or flashing lights. This means that when there is a moving target in the vehicle, for example, due to negligence, a child or baby is left in the vehicle, or an external lawbreaker breaks into the vehicle to commit theft, the user can obtain this message in time through the alarm sound or flashing lights, so as to carry out rescue or prevent theft. In a specific situation, the system can be connected to the user's smartphone wirelessly, so that an alarm sound can be emitted on the smartphone or the flashlight on the smartphone can be caused to flash to remind the user.

[0022] Meanwhile, a vehicle interior moving target detection device is provided, including:

[0023] At least one processor; and at least one memory communicatively connected to the processor, wherein:

[0024] The memory stores program instructions executable by the processor, and the processor can execute the aforementioned vehicle interior moving target detection method by invoking the program instructions. Compared with the prior art, the advantages of the present invention are as follows:

[0025] First of all, as is well known, when the vehicle interior environment changes, for example, because a passenger hangs clothes at a certain position in the vehicle or changes the angle of the vehicle seat, etc., environmental noise will be generated in the vehicle, which causes a large change in the ultrasonic echo signals received by the system before and after, and is misjudged as a moving target in the vehicle, thereby triggering an alarm, which is a false alarm accident. Therefore, it is necessary to evaluate the vehicle interior or surrounding environment, that is, it is necessary to implement the steps of collecting the above environmental interference signals and judging whether the interference is serious. In other words, in the above vehicle interior moving target detection method, since the vehicle interior or surrounding environment is pre-evaluated in advance before collecting and analyzing the ultrasonic echo signals, when it is judged that the environmental interference signal is strong enough that the moving target in the vehicle cannot be accurately detected, the collection and analysis of the ultrasonic echo signals are temporarily stopped. Only when the intensity of the environmental interference signal is within an acceptable range (it will not cause serious interference to the collection of ultrasonic echo signals), the collection and subsequent analysis of the ultrasonic echo signals are carried out, thereby making the detection process accurate and reliable. In contrast, the prior art does not detect environmental interference signals in advance, so its detection results are not accurate and reliable when the environment changes, and false alarms often occur.

[0026] Secondly, in the present invention, the current alarm threshold is corrected based on the current actual environmental signal situation, so as to enable the current alarm threshold to automatically adapt to the actual changes in the current environment, and further eliminate the adverse effects of the changes in the surrounding environment on the detection action, and avoid the occurrence of misjudgment phenomena, that is, when there is no moving target in the vehicle in the current environment, but due to the change of the environment, the amplitude of the ultrasonic echo signal changes greatly, and it is misjudged as being caused by the movement of the target, and finally it is wrongly considered that there is a moving target in the vehicle.

[0027] Additional aspects and advantages of the present invention will be given in part in the following description, and these will become apparent from the following description, or can be understood through the practice of the present invention. Description of the Drawings

[0028] The above and / or additional aspects and advantages of the present invention will become apparent and easy to understand from the following description of the embodiments in conjunction with the drawings, wherein:

[0029] Figure 1 A flowchart of a method for detecting a moving target inside a vehicle according to an embodiment of the present invention;

[0030] Figure 2 Shows the acquisition of environmental interference signals under ideal conditions and the waveforms of the acquired signals;

[0031] Figure 3 Shows the acquisition of environmental interference signals under real conditions and the waveforms of the acquired signals;

[0032] Figure 4 Shows the comparison result of the amplitude curves of ultrasonic echo signals collected twice before and after. Detailed implementation manners

[0033] The embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described by referring to the drawings below are exemplary and are only used to explain the present invention and cannot be construed as a limitation to the present invention.

[0034] Those skilled in the art of the present technology can understand that, unless specifically stated otherwise, the singular forms "a", "an", "the" and "said" used herein may also include the plural forms. It should be further understood that the term "including" used in the specification of the present invention means the presence of the described features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or their groups. It should be understood that when we say an element is "connected" or "coupled" to another element, it can be directly connected or coupled to other elements, or there may also be intermediate elements. In addition, the "connection" or "coupling" used herein may include wireless connection or wireless coupling. The phrase "and / or" used herein includes all or any unit and all combinations of one or more related listed items.

[0035] Those skilled in the art of the present technology can understand that, unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as the general understanding of those of ordinary skill in the art to which the present invention belongs. It should also be understood that terms such as those defined in a general dictionary should be understood to have a meaning consistent with the meaning in the context of the prior art, and will not be interpreted with an idealized or overly formal meaning unless specifically defined as here.

[0036] The present invention provides a method and device for detecting moving targets inside a vehicle. By collecting and processing environmental interference signals inside the vehicle, and then judging the severity of the collected environmental interference signals, when the number of times the amplitude of the environmental interference signal exceeds a preset interference signal threshold is greater than a total number threshold, it is considered that the environmental interference inside the vehicle is severe, and at this time, moving target detection is no longer performed; otherwise, the threshold of the ultrasonic echo signal during moving target detection is adjusted and compensated according to the severity of the interference, so as to eliminate the influence of the environmental interference signal on the ultrasonic echo signal during the detection process, thereby being able to accurately detect moving targets inside the vehicle and avoid false alarms.

[0037] Reference Figure 1 According to an embodiment of the present invention, a method for detecting moving targets inside a vehicle is provided, which includes the following steps:

[0038] Step 102: Collect environmental interference signals;

[0039] Step 104: Judge whether the number of times the amplitude of the environmental interference signal exceeds a preset interference signal threshold is greater than a total number threshold. If so, clear the alarm; otherwise, execute the following step 106;

[0040] Step 112: Clear the alarm;

[0041] Step 106: Collect the first ultrasonic echo signal, and then, after executing steps 102 and 104 again, collect the second ultrasonic echo signal;

[0042] Step 108: Calculate the absolute difference between the amplitude of each ultrasonic signal of the first ultrasonic echo signal and the ultrasonic signal collected at the corresponding moment of the second ultrasonic echo signal;

[0043] Step 110: Accumulate all the absolute differences to form a total absolute difference;

[0044] Step 116: Judge whether the total number of times the total absolute difference is greater than the current alarm threshold is not less than the alarm number threshold. If so, determine that there is a moving target inside the vehicle; otherwise, execute step 112.

[0045] In this embodiment, due to changes in the vehicle interior environment, such as passengers hanging clothes, ornaments, etc. at a certain position inside the vehicle, or using an air gun to deflate, shaking a keychain, knocking on the car window glass, etc., environmental noise will be generated inside the vehicle, which causes a large change in the ultrasonic echo signals received by the system before and after, and is misjudged as having a moving target inside the vehicle, thereby triggering an alarm. This is a false alarm accident, or an untrue alarm event. Therefore, it is necessary to sample the environmental interference signal in advance, that is, before executing the above steps 106 - 116, it is necessary to execute the steps (102 - 104) of collecting and judging the environmental interference signal.

[0046] Preferably, the environmental interference signal is collected at a frequency of 1 KHz within the first collection period of 220 ms. This means that the collection speed is: collecting the environmental interference signal once every 1 ms. This can ensure that a sufficient number of environmental interference signals are collected within a short time, so as to accurately analyze the intensity of the environmental interference signal and then draw a conclusion on whether there is serious interference.

[0047] For the specific collection of the environmental interference signal and the waveform of the collected signal, please refer to Figure 2 . In Figure 2 , the abscissa represents the collection time, with the unit of ms, and the ordinate represents the amplitude of the collected environmental interference signal, with the unit of 1 lsb. The red line represents the curve of the amplitude change of the environmental interference signal over time. This Figure 2 shows the environmental interference signal under ideal conditions, so it is a red straight line overlapping with the abscissa within the first collection period (within the first 220 ms). Figure 3 shows the curve of the environmental interference signal under actual conditions. In this figure, the meanings represented by the abscissa and the ordinate are the same as those in Figure 2 . The difference is that within the first collection period (the first 220 ms), the environmental interference signal is a fluctuating curve, so it shows the real in-vehicle environment.

[0048] In one embodiment, preferably, the preset interference signal threshold is calibrated in the following manner:

[0049] By continuously simulating the real in-vehicle environment, including using an air gun to deflate, shaking a keychain, knocking on the car window glass, etc. to simulate environmental interference signals under different situations in the vehicle, and then respectively measuring the data of the environmental interference signals collected under these different working conditions, and then taking 0.8 times the minimum amplitude of the environmental interference signal and setting it as the preset interference signal threshold. By this setting method, the preset interference signal threshold can be set in a way as close to the real situation as possible.

[0050] Preferably, in step 104 above, the value range of the total number threshold is 2 - 10. Through multiple environmental simulations, it is verified that the total number threshold within the above value range can relatively ideally conform to the real situation of the environmental interference signals under various different on-site environments. Further preferably, the value of the total number threshold is 7.

[0051] In step 112 above, clearing the alarm means canceling or pausing the alarm signal sent to the user indicating the presence of a moving target in the vehicle. Specifically, it may include but is not limited to: canceling or pausing the sound alarm signal, the light flashing alarm signal, etc., to avoid false alarms and thus causing unnecessary panic and tension to the user.

[0052] When the judgment result in step 104 is negative, it means that the current in-vehicle environment tends to be stable (little or no change). At this time, the acquisition process of the ultrasonic echo signal is started (step 106).

[0053] In one embodiment, preferably, in step 106, in one embodiment, preferably, in the step of acquiring the ultrasonic echo signal, the acquisition of the first ultrasonic echo signal includes: within a second acquisition period: the ultrasonic transmitter emits a first pulse signal with a specific duty cycle; and the first ultrasonic echo signal formed after the reflection of the first pulse signal is received by the ultrasonic receiver.

[0054] The acquisition of the second ultrasonic echo signal includes: within another second acquisition period: the ultrasonic transmitter emits a second pulse signal with a specific duty cycle; and the second ultrasonic echo signal formed after the reflection of the second pulse signal is received by the ultrasonic receiver.

[0055] Preferably, preferably, the time interval between the acquisition of the first ultrasonic echo signal and the acquisition of the second ultrasonic echo signal is 250 ms.

[0056] Preferably, the number ranges of the first and second pulse signals emitted are both 16 - 40, and they can be determined according to the actual calibration situation. Practice has proved that the pulse signals within this number range can ensure the acquisition of a sufficient number of ultrasonic echo signals, and then a sufficient number of ultrasonic echo signals can be analyzed to accurately judge whether there are moving targets in the vehicle, such as young passengers in the vehicle or lawless elements invading from the outside. Further preferably, the frequencies of the first and second pulse signals emitted are both 40 kHz, and their duty cycles are both 50%.

[0057] Preferably, the acquisition frequencies of the first and second ultrasonic echo signals are both 20 kHz, the second acquisition period is 30 ms, and the number of the first and second ultrasonic echo signals acquired is both 600.

[0058] According to the above description, the number of ultrasonic echo signals acquired in the two consecutive times is 600 each. Therefore, the absolute differences of the amplitudes of the 600 corresponding ultrasonic echo signals are accumulated to form the total absolute difference. The comparison of the amplitude curves of the ultrasonic echo signals acquired in the two consecutive times is as Figure 4As shown. As shown in the figure, the abscissa represents time, with the unit of ms, and the ordinate represents the amplitude of the collected ultrasonic echo signal, with the unit of 1 lsb. The blue curve represents the variation of the amplitude of the first (nth) ultrasonic echo signal with time, while the red curve represents the variation of the amplitude of the second ((n + 1)th) ultrasonic echo signal with time. This indicates that the currently detected environment is stable, and the waveform fluctuations of the ultrasonic echo signals in the previous and subsequent times are small, and no moving targets, such as children or lawbreakers, are detected in the vehicle.

[0059] According to an embodiment of the present invention, the amplitudes of the first collected ultrasonic echo signals are respectively denoted as i1 to i 600 , and the amplitudes of the second collected ultrasonic echo signals are respectively denoted as j1 to j 600 , then the total absolute difference = |i1 - j1| + |i2 - j2| +... + |i 600 - j 600 |).

[0060] According to the above description, the number of ultrasonic echo signals collected in both the previous and subsequent times is 600. Therefore, in step 114, the absolute differences of the amplitudes of the 600 corresponding ultrasonic echo signals are accumulated to form the total sum of the absolute differences.

[0061] Preferably, in an embodiment, after accumulating all the absolute differences to form the total absolute difference, before determining whether the total number of times the total absolute difference within a period of time is greater than the current alarm threshold is not less than the alarm times threshold, it further includes: calculating the current alarm threshold based on the minimum calibrated alarm threshold. The purpose of performing this step is to correct the current alarm threshold based on the current actual environmental signal situation, so as to enable the current alarm threshold to automatically adapt to the actual changes in the current environment, and further eliminate the adverse effects of the changes in the surrounding environment on the detection action, and avoid the occurrence of misjudgment phenomena (that is, there are no moving targets in the vehicle in the current environment, but due to the change of the environment, the amplitude of the ultrasonic echo signal received by the system changes greatly, and thus it is mistakenly considered to be caused by the movement of the target, and finally it is wrongly considered that there are moving targets in the vehicle).

[0062] Preferably, in an embodiment, the calculating the current alarm threshold based on the minimum calibrated alarm threshold includes: when the sum of the amplitudes of all the second collected ultrasonic echo signals is not greater than 300000, setting the minimum calibrated threshold as the current alarm threshold; otherwise, the current alarm threshold = the minimum calibrated threshold + (the total absolute difference - 300000) / R, where R is the change amount threshold coefficient. Further preferably, the value range of the change amount threshold coefficient R is 10 to 50.

[0063] In the above embodiments, when the environmental interference signal is weak, it can be considered that the impact of the signal on the detection of moving targets is very small. Therefore, the minimum calibration threshold can be used as the critical value to determine whether there is a moving target in the vehicle. When the environmental interference signal is slightly stronger, although it has an interference effect, this interference effect still satisfies the negative determination result in step 104 above. However, at this time, it is necessary to appropriately increase the value of the current alarm threshold. The specific degree of increase is determined according to the above formula (current alarm threshold = minimum calibration threshold + (sum of absolute differences - 300000) / R) to eliminate the adverse effect of the environmental interference signal and avoid false alarms.

[0064] Preferably, after determining whether the total number of times the sum of absolute differences in a period of time is greater than the current alarm threshold is not less than the alarm count threshold, it further includes: reminding the user that there is a moving target in the vehicle. This is because when it is determined that there is a moving target in the vehicle, only the system obtains this result, but the user does not know. Therefore, it is necessary to warn the user of the same information through appropriate means such as sound or flashing lights. This means that when there is a moving target in the vehicle, for example, due to negligence, a child or baby is left in the vehicle by mistake, or an external lawbreaker breaks the window and enters the vehicle to commit theft, the user can obtain this message in time through the alarm sound or flashing lights, so as to carry out rescue or prevent theft. In a specific situation, the system can communicate with the user's smartphone wirelessly, so that an alarm sound can be emitted on the smartphone or the flashlight on the smartphone can be caused to flash to remind the user.

[0065] Preferably, the total number of times the sum of absolute differences is greater than the current alarm threshold is counted within at least 500 ms.

[0066] The present invention also provides a device for detecting moving targets in a vehicle, including:

[0067] At least one processor; and at least one memory communicatively connected to the processor, wherein:

[0068] The memory stores program instructions executable by the processor, and the processor can execute the method for detecting moving targets in a vehicle described in the above embodiments by calling the program instructions.

[0069] Those skilled in the art can understand that the various operations, methods, steps, measures, and solutions in the processes discussed in this application can be alternated, changed, combined, or deleted. Further, other steps, measures, and solutions in the various operations, methods, and processes discussed in this application can also be alternated, changed, rearranged, decomposed, combined, or deleted. Further, those in the prior art that have steps, measures, and solutions in the various operations, methods, and processes disclosed in this application can also be alternated, changed, rearranged, decomposed, combined, or deleted.

[0070] The above are only some embodiments of this application. It should be noted that for those of ordinary skill in the art, without departing from the principle of this application, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of this application.

Claims

1. A method for detecting moving targets inside a vehicle, characterized in that Including: Collecting environmental interference signals; Judging whether the number of times that the amplitude of the environmental interference signal exceeds a preset interference signal threshold is greater than a total number threshold. If so, clearing the alarm; otherwise, performing the following steps; Collecting a first ultrasonic echo signal, and then, after performing again the steps of collecting the environmental interference signal and judging whether the number of times that the amplitude of the environmental interference signal exceeds the preset interference signal threshold is greater than the total number threshold, collecting a second ultrasonic echo signal; Calculating the absolute difference between each ultrasonic signal of the first ultrasonic echo signal and the ultrasonic signal collected at the corresponding moment of the second ultrasonic echo signal; Accumulating all the absolute differences to form an absolute difference sum; and Judging whether the total number of times that the absolute difference sum is greater than the current alarm threshold is not less than an alarm number threshold. If so, determining that there is a moving target in the vehicle; otherwise, clearing the alarm.

2. The in-vehicle moving target detection method according to claim 1, wherein: The clearing the alarm includes canceling or pausing the alarm signal sent to the user indicating that there is a moving target in the vehicle.

3. The in-vehicle moving target detection method according to claim 2, wherein: The alarm signal includes a sound alarm signal or a light alarm signal.

4. The in-vehicle moving target detection method according to claim 1, characterized in that: The collecting the first ultrasonic echo signal includes: the ultrasonic transmitter transmitting a first pulse signal; and the ultrasonic receiver receiving the first ultrasonic echo signal formed after the reflection of the first pulse signal.

5. The vehicle interior moving target detection method according to claim 4, wherein: The collecting the second ultrasonic echo signal includes: the ultrasonic transmitter transmitting a second pulse signal; and the ultrasonic receiver receiving the second ultrasonic echo signal formed after the reflection of the second pulse signal.

6. The in-vehicle moving target detection method according to claim 1, characterized in that: After the accumulating all the absolute differences to form the absolute difference sum and before judging whether the total number of times that the absolute difference sum within a period of time is greater than the current alarm threshold is not less than the alarm number threshold, further including: calculating the current alarm threshold based on the minimum calibrated alarm threshold.

7. The in-vehicle moving target detection method according to claim 6, wherein: The calculating the current alarm threshold based on the minimum calibrated alarm threshold includes: when the sum of the amplitudes of all the collected second ultrasonic echo signals is not greater than 300,000, setting the minimum calibrated threshold as the current alarm threshold; otherwise, the current alarm threshold = the minimum calibrated threshold + (the absolute difference sum - 300,000) / R, where R is a change amount threshold coefficient.

8. The in-vehicle moving target detection method according to claim 7, wherein: The value range of the change amount threshold coefficient R is 10 to 50.

9. The in-vehicle moving target detection method according to claim 1, characterized in that: After judging whether the total number of times that the absolute difference sum within a period of time is greater than the current alarm threshold is not less than the alarm number threshold, further including: reminding the user that there is a moving target in the vehicle.

10. An in-vehicle moving target detection device, characterized in that Including: At least one processor; And at least one memory communicatively connected to the processor, wherein: The memory stores program instructions executable by the processor, and the processor can execute the method for detecting a moving target in a vehicle according to any one of claims 1-9 by invoking the program instructions.

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