Kick sensor and method for detecting a kick

Abstract

A kick sensor and a kick action detection method capable of avoiding missed detection due to discontinuity between approach and away actions. The kick sensor of the present invention includes a sensing portion provided to a vehicle for detecting an object, and a control portion for judging an approach action of the object to the sensing portion and an away action of the object from the sensing portion based on a detection result of the sensing portion, characterized in that the control portion has an extraction portion for extracting a low-speed action between the approach action and the away action of the object, a comparison portion for comparing a feature of the low-speed action with features of the approach action and the away action, and a judgment portion for judging whether a kick action has been performed based on continuity between the low-speed action, the approach action, and the away action.

Description

Technical Field

[0001] This invention relates to a kick sensor for vehicles and a method for detecting kicking motions. Background Technology

[0002] In existing vehicles such as gasoline-powered cars and electric vehicles, there are systems that detect the user's kicking motion and open or close doors such as the tailgate. Such systems include kick sensors that detect the user's kicking motion.

[0003] The conventional method of kick sensor detection is to detect the approach and departure of the foot. Patent document 1 describes a kick sensor that can obtain the speed of the object and calculate the distance of the foot approaching the vehicle and the distance of the foot away from the vehicle by integrating the speed, and use the approach and departure distances of the foot to identify the kicking action.

[0004] Patent Document 1: WO2024176596A1

[0005] Due to differences in individual usage habits, some users hold their feet suspended for a period of time after completing the approaching motion before moving away. The radar, acting as a kick sensor, typically does not detect this suspension period. This is because a large number of stationary objects may exist within the radar's field of view, and filtering out signals from stationary objects is a common practice. Consequently, signals generated during foot suspension or low-speed movement are also filtered out along with signals from other stationary objects. Since a portion of the kicking motion is not detected, the kicking signal detected for kicking movements where the approaching and moving away actions are discontinuous is discontinuous, increasing the likelihood of missed detections. Summary of the Invention

[0006] The present invention was made in view of the following problem, and provides a kick sensor and a kick action detection method that can avoid missed detections caused by the discontinuity between approach and departure actions.

[0007] The present invention provides a kick sensor comprising: a sensing unit disposed in a vehicle for detecting an object; and a control unit for determining, based on the detection result of the sensing unit, an approaching action of the object approaching the sensing unit and a moving-away action of the object away from the sensing unit. The control unit is characterized by comprising: an extraction unit for extracting a low-speed action between the approaching action and the moving-away action of the object; a comparison unit for comparing the characteristics of the low-speed action with the characteristics of the approaching action and the moving-away action; and a determination unit for determining, based on the continuity between the low-speed action, the approaching action, and the moving-away action, whether a kicking action has occurred.

[0008] In the kick action detection method based on a kick sensor of the present invention, the kick sensor includes: a sensing unit disposed in a vehicle for detecting an object; and a control unit for determining the action of the object based on the detection result of the sensing unit. The kick action detection method is characterized by the following steps: based on the detection result of the sensing unit, extracting an approaching action of the object approaching the sensing unit, a moving-away action of the object away from the sensing unit, and a low-speed action between the approaching action and the moving-away action; comparing the characteristics of the low-speed action with the characteristics of the approaching action and the moving-away action; and determining whether a kicking action has occurred based on the continuity between the low-speed action, the approaching action, and the moving-away action.

[0009] Invention Effects

[0010] The kick sensor and kick motion detection method of the present invention can obtain detection signals of continuous kick motions, including low-speed motions, and can avoid missed detections caused by the discontinuity of approach and departure motions. Attached Figure Description

[0011] Figure 1 This is a diagram showing the system configuration of the vehicle-mounted system according to the first embodiment.

[0012] Figure 2 It is a diagram used to illustrate the user's kicking motion.

[0013] Figure 3 This is a diagram illustrating the change in distance between the user's foot and the vehicle during a kicking motion.

[0014] Figure 4 This is a diagram illustrating the change in the speed of the user's foot during a kicking motion.

[0015] Figure 5 This is a diagram showing the functional modules of the control unit for the kick sensor.

[0016] Figure 6 This is a flowchart of the foot kicking action detection and processing by the foot kicking sensor.

[0017] Figure 7 This is a flowchart of the preprocessing in the kicking motion detection and processing.

[0018] Figure 8A , Figure 8B and Figure 8C It is a diagram used to illustrate the various signals related to preprocessing.

[0019] Figure 9 This is a flowchart of the judgment and processing in the kicking action detection process.

[0020] Figure 10 This is a flowchart of the preprocessing in the kicking action detection process of Variation Example 1.

[0021] Figure 11 This is a flowchart of the judgment process in the kicking action detection process of Variation Example 2.

[0022] Figure Labels

[0023] 1. Vehicle-mounted system

[0024] 2. Feet (example of an object)

[0025] 10 vehicles

[0026] 11. Tailgate

[0027] 12 Electronic Control Units (ECUs)

[0028] 100 kick sensors

[0029] 101 Sensor Department

[0030] 102 Low-pass filter section

[0031] 103 Control Department

[0032] 1031 Pre-processing Department

[0033] 1032 Extraction Section

[0034] 1033 Comparison Department

[0035] 1034 Judgment Department

[0036] Detection range of Radar 201

[0037] D1 First Distance

[0038] D2 Second Distance

[0039] G1 First time interval

[0040] G2 Second time interval

[0041] S1 Approach Action

[0042] S2 Low-speed action

[0043] S3 Stay Away From Action

[0044] T Total Duration

[0045] T2 Duration of low-speed motion

[0046] Ys velocity threshold

[0047] Y1 First Threshold

[0048] Y2 second threshold

[0049] Y3 Third Threshold

[0050] Y4 fourth threshold

[0051] Time points t1, t2, t3, t4 Detailed Implementation

[0052] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0053] First Implementation Method

[0054] <System Configuration>

[0055] Figure 1 This diagram illustrates the system configuration of the vehicle-mounted system according to the first embodiment. Vehicle-mounted system 1 is a system that uses a kick sensor 100 installed in the vehicle 10 to detect kicking actions of a user's foot 2, etc., and to open or close the doors of the vehicle 10. Figure 1 In the vehicle system 1, the foot-operated sensor 100 located at the rear of the vehicle 10 and an electronic control unit (ECU) 12 for controlling the opening and closing of the tailgate (or trunk) are included.

[0056] The foot kick sensor 100 includes: a sensing unit 101 that detects signals indicating the approach and departure of a user's foot 2; a low-pass filter unit 102 that detects signals related to a stationary object (not shown); and a control unit 103 that determines the movement of the foot 2 based on the detection results of the sensing unit 101. The sensing unit 101 is, for example, a PCR radar (Pulse Coherent Radar), the low-pass filter unit 102 is, for example, a low-pass filter, and the control unit 103 detects the distance between the foot 2 and the sensing unit 101 by calculating the round-trip time or phase difference of the signal. Furthermore, the control unit 103 can also utilize the Doppler effect to analyze changes in the echo frequency to calculate the speed of the foot 2. In this embodiment, the foot 2 is an example of an object, and the foot 2 may also include the lower leg near the foot.

[0057] The control unit 103 also extracts the approaching action of the foot 2 approaching the sensor unit 101, the moving away action of the foot 2 away from the sensor unit 101, and the low-speed action between the approaching action and the moving away action based on the calculated distance, speed and other information, and determines whether the user has performed a kicking action and outputs the result.

[0058] The electronic control unit 12 opens and closes the tailgate 11 of the vehicle 10 based on the detection results of the kicking action output from the control unit 103. It should be noted that... Figure 1The system configuration of the vehicle system 1 shown is only one example. For example, the control unit 103 of the foot kick sensor 100 and the electronic control unit 12 can also be implemented by a single ECU. Furthermore, the electronic control unit 12 can control the opening and closing of other doors of the vehicle 10 besides the tailgate 11 based on the detection results from the foot kick sensor 100.

[0059] Furthermore, the radar in the sensing unit 101 is not limited to a PCR radar for measuring distance, but can also be other types of radar such as an FMCW radar (Frequency-Modulated Continuous Wave Radar). In this embodiment, the case where the sensing unit 101 is a PCR radar will be described as an example. In the following description, PCR radar will sometimes be simply referred to as radar. Furthermore, the sensing unit 101 is not limited to radar, and can also be, for example, an ultrasonic sensor for measuring distance. The low-pass filter unit 102 can be an analog low-pass filter or a digital low-pass filter.

[0060] Furthermore, the control unit 103 of the kick sensor 100 and the electronic control device 12 are implemented, for example, by a computer. The computer can be a hardware configuration with a processor, memory, communication I / F (interface), external connection I / F, bus, etc., or it can be implemented by an MCU (microcontroller unit) or SoC (system-on-chip).

[0061] Figure 2 This is a diagram used to illustrate a user's kicking motion. For example... Figure 2 As shown, the sensor 101 transmits a signal within the radar's detection range 201 and measures the received signal received from the signal reflected by the foot 2, thereby detecting the user's foot 2 approaching or moving away.

[0062] like Figure 2 As shown, the kicking action can be broken down into three actions, including: approaching action S1 where foot 2 gradually approaches sensor 101, low-speed action S2 where foot 2 is suspended at the position approaching sensor 101, and moving away action S3 where foot 2 gradually moves away from sensor 101.

[0063] Figure 3 This diagram illustrates the change in distance between the user's foot 2 and the vehicle 10 during a kicking motion. During the approaching action S1, the distance between foot 2 and the ground gradually increases, while the distance between foot 2 and the rear of the vehicle 10 gradually decreases. During the low-speed action S2, the distance between foot 2 and the ground, as well as the distance between foot 2 and the vehicle 10, remain relatively stable, with foot 2 positioned close to the rear of the vehicle 10. During the moving away action S3, the distance between foot 2 and the rear of the vehicle 10 gradually increases, while the distance between foot 2 and the ground gradually decreases.

[0064] Based on signals from PCR radar, it is possible to obtain Figure 4 The data shown. Figure 4 This is a diagram illustrating the change in the speed of the user's foot during a kicking motion. Figure 4 The horizontal axis represents the passage of time, and the vertical axis represents the speed of the user's foot. Figure 4 In the figure, velocity curve 301 represents the velocity change of the user's foot 2 during the kicking action.

[0065] At time t1, the velocity value of foot 2 is negative, which indicates that foot 2 has a velocity approaching the sensor 101 of vehicle 10.

[0066] At time t2, the velocity value is still negative, and the absolute value of the velocity value is equal to the velocity threshold Ys. The period from time t1 to time t2 (including time t1 but excluding time t2) is the duration of the approach action S1. That is, the velocity signal acquired during the duration of the approach action S2 indicates that foot 2 has a velocity approaching vehicle 10, and the absolute value of the velocity signal is greater than the velocity threshold Ys.

[0067] At time t3, the speed value of foot 2 is positive, indicating that foot 2 has a speed moving away from the sensor 101 of vehicle 10. Furthermore, at time t3, the absolute value of the speed value is equal to the speed threshold Ys. The period from time t2 to time t3 (including time t2 and time t3) is the duration of the low-speed action S2. That is, the speed signal acquired during the duration of the low-speed action S2 indicates that foot 2 has a speed approaching or moving away from vehicle 10, and the absolute value of the speed signal is less than or equal to the speed threshold Ys.

[0068] At time point t4, the velocity value is also positive, and the absolute value of the velocity value is greater than the velocity threshold Ys. The period from time point t3 to time point t4 (excluding time point t3 but including time point t4) is the duration of the movement away from action S3. That is, the velocity signal acquired during the duration of the movement away from action S3 indicates that foot 2 has a velocity away from vehicle 10, and the absolute value of the velocity signal is greater than the velocity threshold Ys.

[0069] Here, the speed threshold Ys is a value used to distinguish between approaching action S1 and low-speed action S2, and also a value used to distinguish between low-speed action S2 and moving away action S3. The speed threshold Ys is a value set based on statistical data from actual users, and in this embodiment, it is set to, for example, 200 mm / s.

[0070] Furthermore, the division of the duration of the approaching action S1, the low-speed action S2, and the moving-away action S3 described above is merely an example and is not limited to this. For instance, it could also be divided into the period from time point t1 to time point t2 (inclusive of time points t1 and t2) being the duration of the approaching action S1, the period from time point t2 to time point t3 (exclusive of time points t2 and t3) being the duration of the low-speed action S2, and the period from time point t3 to time point t4 (inclusive of time points t3 and t4) being the duration of the moving-away action S3.

[0071] <Function Configuration>

[0072] Figure 5 This diagram shows the functional modules of the control unit 103 of the kick sensor 100. The control unit 103 of the kick sensor 100 further includes a preprocessing unit 1031, an extraction unit 1032, a comparison unit 1033, and a judgment unit 1034.

[0073] The preprocessing unit 1031 subtracts the signal related to the stationary object obtained by the low-pass filter unit 102 from the received signal of the sensing unit 101, thereby obtaining a signal containing the signal related to the low-speed action S2.

[0074] The extraction unit 1032 extracts the approach action S1, the departure action S3, and the low-speed action S2 located between the approach action S1 and the departure action S3 of the extraction foot 2.

[0075] The comparison unit 1033 compares the characteristics of the low-speed action S2 with the characteristics of the approaching action S1 and the moving-away action S3.

[0076] The judgment unit 1034 determines the continuity between the low-speed action S2, the approaching action S1, and the moving away action S3 based on the comparison result of the comparison unit 1033, and determines whether a kicking action has been performed.

[0077] also, Figure 5 The functional modules of the control unit 103 are just one example. The control unit 103 only needs to be able to perform the processing of the preprocessing unit 1031, extraction unit 1032, comparison unit 1033 and judgment unit 1034. Of course, it can also have other functional modules.

[0078] <Processing Flow>

[0079] Next, the processing flow of the kicking action detection method of this embodiment will be explained.

[0080] Figure 6 This is a flowchart illustrating the kick motion detection and processing by the kick sensor. This processing is... Figure 1 An example of kick action detection processing performed by the control unit 103 of the kick sensor 100 in the vehicle system 1 shown.

[0081] In step S11, the control unit 103 acquires received signals from the sensor unit 101 at a predetermined period. This predetermined period is, for example, set to 1 / 30 of a second, in which case the control unit 103 acquires received signals from the sensor unit 101 30 times per second. Furthermore, the control unit 103 also acquires transmitted signals from the sensor unit 101 at the same predetermined period.

[0082] The received signal here is from a PCR radar. The received signal from a PCR radar is an IQ signal (In-phase and Quadrature signal) composed of two components with a 90-degree phase difference.

[0083] Next, in step S12, the preprocessing unit 1031 of the control unit 103 preprocesses the received signal of the sensing unit 101.

[0084] Figure 7 This is a flowchart of the preprocessing (step S12) in the kicking action detection process. Figure 8A , Figure 8B and Figure 8C It is a diagram used to illustrate the various signals related to preprocessing. Figure 8A , Figure 8B and Figure 8C The horizontal axis represents time (in seconds), and the vertical axis represents signal strength (in millivolts).

[0085] like Figure 7 As shown, in step S121, the received signal from the sensing unit 101 is filtered by the low-pass filter 102. Figure 8A The signal corresponding to the curve in the image is processed to obtain the low-pass filtered signal. Figure 8B The signal corresponding to the curve in the graph. The low-pass filtered signal is a signal related to a stationary object.

[0086] To be more detailed, Figure 8A , Figure 8B and Figure 8C The curves shown are signals selected from the received signals of the sensor unit 101 at a distance of approximately 200 mm from the vehicle 10. This 200 mm is just an example; since different users' kicking actions vary, the distance between their foot and the vehicle also varies. Therefore, preprocessing requires processing multiple distances (e.g., 0 mm, 50 mm, 100 mm, 150 mm, 200 mm, 250 mm, 300 mm, etc.). Figure 8A , Figure 8B and Figure 8C The processing shown.

[0087] Next, in step S122, the preprocessing unit 1031 receives the signal from the sensing unit 101 ( Figure 8A The signal corresponding to the curve in the image is the signal after low-pass filtering (subtracted from the signal in the image). Figure 8B The signal corresponding to the curve in the image is obtained, thus yielding a signal containing a signal related to the low-speed action S2 of foot 2. Figure 8C (The signal corresponding to the curve in the image).

[0088] like Figure 8A and Figure 8B As shown, before the signal received by the sensor unit 101 is subtracted from the signal obtained after low-pass filtering, the signal received by the sensor unit 101 includes not only the signal received from foot 2, but also the signal from stationary objects near the vehicle 10. These stationary objects refer to ground protrusions used to locate the reversing position of the wheels, parking barriers in paid parking lots, items temporarily placed around the vehicle, and other objects that remain stationary for extended periods. On the other hand, after the signal received by the sensor unit 101 is subtracted from the signal obtained after low-pass filtering, such as... Figure 8C As shown, background noise related to stationary objects in these original signals is removed, but signals related to the low-speed action S2 of foot 2 are reliably preserved.

[0089] Next, in step S123, the preprocessing unit 1031 obtains the speed signal (speed value) of foot 2 by performing FFT (Fast Fourier Transform) on the signal containing the signal related to the low-speed action S2 of foot 2. In addition, the preprocessing unit 1031 can also calculate the distance value between foot 2 and vehicle 10 based on the transmitted and received signals of the sensing unit 101.

[0090] Return to Figure 6 Next, in step S13, the extraction unit 1032, based on the processing result of step S12 and a preset speed threshold Ys used to distinguish between approaching action S1, low-speed action S2, and moving away action S3, performs the extraction based on the speed threshold Ys. Figure 4 Extract the approaching action S1, the moving away action S3, and the low-speed action S2 located between the approaching action S1 and the moving away action S3, respectively.

[0091] Next, in step S14, the comparison unit 1033 compares the features of the low-speed action S1 with the features of the approaching action S2 and the moving-away action S3. The features of the approaching action S1 may include the start time, end time, duration, start position, and end position of the approaching action S1. The features of the low-speed action S2 include the start time, end time, duration, start position, and end position of the low-speed action S2. The features of the moving-away action S3 include the start time, end time, duration, start position, and end position of the moving-away action S3.

[0092] Next, in step S15, the determination unit 1034 determines the continuity between the low-speed action S2, the approaching action S1, and the moving away action S3 based on the comparison result of the comparison unit 1033, and determines whether a kicking action has been performed. In order to determine the continuity between each action, the following four methods are used to make the determination sequentially.

[0093] Method 1: Continuity refers to the situation where the first time interval G1 between the start time of low-speed action S2 and the end time of action S1, and the second time interval G2 between the end time of low-speed action S2 and the start time of action S3, are below the first threshold Y1.

[0094] The first threshold Y1 can be preset based on the actual value of the detection signal of the actual kicking action. When the control unit 103 receives 30 signals from the sensor unit 101 per second, the first threshold Y1 needs to be at least greater than 1 / 30 of a second. Considering that there may be cases where the control unit 103 fails to receive signals from the sensor unit 101, it can be set to a value between 100 milliseconds and 150 milliseconds.

[0095] Method 2: Continuity refers to the situation where the total duration T of the approaching action S1, the slow action S2, and the moving away action S3 is below the second threshold Y2.

[0096] Method 3: Continuity refers to the case where the duration T2 of the low-speed action S2 is below the third threshold Y3.

[0097] Method 4: Continuity refers to the situation where the first distance D1 between the start position of low-speed action S2 and the end position approaching action S1, and the second distance D2 between the end position of low-speed action S2 and the start position away from action S3, are both below the fourth threshold Y4. The fourth threshold Y4 can be preset based on the actual value of the detection signal of the actual kicking action. When the control unit 103 receives 30 signals per second from the sensor unit 101, it can be set to a value between 60mm and 180mm.

[0098] Figure 9 This is a flowchart of the judgment process (step S15) in the kicking action detection process of the first embodiment. For example... Figure 9 As shown, the judgment unit 1034 sequentially judges the continuity of the above-mentioned methods 1 to 4. If the continuity of methods 1 to 4 is valid, it is judged that a kicking action has been performed.

[0099] Return to Figure 6 After step S15, proceed to step S16 and output the detection result that a kicking action was detected.

[0100] The technical effects of the kick sensor 100 of the first embodiment will now be explained.

[0101] By obtaining continuous kicking motions, including the low-speed motion S2, it is possible to avoid missed detections caused by the discontinuity between the approaching motion S1 and the moving-away motion S3.

[0102] Furthermore, by defining the temporal continuity between low-speed action S2 and approaching action S1, as well as between low-speed action S2 and moving away action S3, the possibility of actions other than kicking actions being mistakenly detected as kicking actions can be reduced.

[0103] Furthermore, by limiting the total duration of the kicking action through the second threshold Y2, the possibility of actions other than kicking actions being mistakenly detected as kicking actions can be further reduced.

[0104] Furthermore, by limiting the duration of the low-speed action S2 through the third threshold Y3, the possibility of actions other than kicking being mistakenly detected as kicking actions can be further reduced.

[0105] Furthermore, by using the fourth threshold Y4 to limit the spatial continuity between low-speed action S2 and approaching action S1, as well as between low-speed action S2 and moving away action S3, the possibility of actions other than kicking actions being mistakenly detected as kicking actions can be further reduced.

[0106] Furthermore, by considering the direction of the velocity signal of foot 2 and comparing the absolute value of the velocity signal with the velocity threshold Ys, the kicking action can be accurately divided into approaching action S1, low-speed action S2, and moving away action S3.

[0107] Furthermore, by removing noise signals related to stationary objects around the vehicle 10 through the low-pass filter 102, the signal related to the low-speed action S2 of the foot 2 can be reliably retained, and the extraction unit 1032 can reliably extract the approach action S1, the low-speed action S2, and the moving-away action S3.

[0108] Alternatively, the low-pass filter unit 102 may be omitted and the low-pass filtering process in step S12 may not be performed due to factors such as cost. However, in this case, the extraction accuracy of the low-speed action S2 may be reduced to some extent.

[0109] Variation Example 1

[0110] Figure 10 This is a flowchart of the preprocessing in the kicking action detection process of Modified Example 1. Steps S121A, S122A, and S123A in the preprocessing of Modified Example 1 are different from steps S121, S122, and S123 in the first embodiment.

[0111] like Figure 10 As shown, in step S121A, the preprocessing unit 1031 obtains a first velocity signal representing the velocity values ​​of foot 2 and the stationary object by performing FFT (Fast Fourier Transform) on the received signal of the sensing unit 101.

[0112] Next, in step S122A, the obtained first velocity signal is low-pass filtered by the low-pass filter unit 102 to obtain a second velocity signal representing the velocity value of a stationary object.

[0113] Next, in step S123A, the preprocessing unit 1031 subtracts the second speed signal from the first speed signal, thereby obtaining a speed signal representing the speed value of foot 2 after the background noise related to the stationary object has been removed.

[0114] As described above, in the preprocessing, subtraction processing can be performed first and then FFT processing, as in the first embodiment, or FFT processing can be performed first and then subtraction processing, as in Modification 1. Modification 1 can also achieve the same technical effect as the first embodiment.

[0115] Variation Example 2

[0116] In the judgment processing of the kicking action detection process in the first embodiment, the scheme of judging in sequence from method 1 to method 4 is adopted, but in fact, the number and judgment order of methods 1 to 4 can be adjusted.

[0117] Figure 11 This is a flowchart of the judgment process in the kicking action detection process of Variation Example 2. For example... Figure 11 As shown, in Modification 2, a scheme is adopted in which methods 1 to 3 are judged sequentially and methods 1 to 3 are judged in parallel with method 4. The judgment content in each method remains unchanged, and Modification 2 can also achieve the same technical effect as the first embodiment.

[0118] Alternatively, one or more of methods 1 to 4 can be deleted as appropriate.

[0119] Other variations

[0120] The above-described embodiments and variations are merely a few examples, and the present invention is not limited thereto. Those skilled in the art can appropriately add, delete, or modify the constituent elements and combine the features of each embodiment appropriately, as long as they possess the technical concept of the present invention, they are all included within the scope of the present invention.

[0121] For example, unlike PCR radar, when using FMC radar as the sensing unit 101, it is necessary to perform an FFT on the received signal of FMC radar to obtain the distance value, and then perform another FFT to obtain the velocity signal. At the same time, the preprocessing performed by the preprocessing unit 1031 also needs to be changed accordingly.

Claims

1. A foot kick sensor, comprising: The sensing unit, installed in the vehicle, is used to detect objects. as well as The control unit, based on the detection results of the sensing unit, extracts the approach action of the object approaching the sensing unit and the moving away action of the object from the sensing unit. Its features are, The control unit has: The extraction unit extracts the low-speed motion between the approaching motion and the moving away motion of the object; The comparison unit compares the characteristics of the low-speed action with the characteristics of the approaching action and the moving away action; as well as The judgment unit determines the continuity between the low-speed action, the approaching action, and the moving away action based on the comparison result of the comparison unit, and determines whether a kicking action has been performed.

2. The kick sensor according to claim 1, characterized in that, The characteristics of the low-speed action include the start time point and the end time point of the low-speed action. The features of the approaching action and the moving away action include the end time point of the approaching action and the start time point of the moving away action. The continuity refers to the situation where the first time interval between the start time of the low-speed action and the end time of the approaching action, and the second time interval between the end time of the low-speed action and the start time of the moving-away action, are both below a first threshold.

3. The kick sensor according to claim 1, characterized in that, The characteristics of the low-speed action include the duration of the low-speed action. The characteristics of the approaching action and the moving away action include the duration of the approaching action and the moving away action. The continuity refers to the situation where the combined duration of the approaching action, the low-speed action, and the moving away action is below the second threshold.

4. The kick sensor according to claim 1, characterized in that, The characteristics of the low-speed action include the duration of the low-speed action. The continuity refers to the situation where the duration of the low-speed action is below the third threshold.

5. The kick sensor according to claim 1, characterized in that, The characteristics of the low-speed action include the start position of the low-speed action and the end position of the low-speed action. The features of the approaching action and the moving away action include the ending position of the approaching action and the starting position of the moving away action. The continuity refers to the situation where the first distance between the start position of the low-speed action and the end position of the approaching action, and the second distance between the end position of the low-speed action and the start position of the departing action, are both below a fourth threshold.

6. The kick sensor according to claim 1, characterized in that, The sensor unit is a radar capable of detecting both dynamic and stationary objects. The control unit reads the radar's received signal at a predetermined period and obtains a velocity signal corresponding to the received signal, representing the velocity value of the object, through a fast Fourier transform.

7. The kick sensor according to claim 6, characterized in that, The speed signal acquired during the duration of the approach action indicates that the object has a speed approaching the vehicle, and the absolute value of the speed signal is greater than a predetermined speed threshold. The speed signal acquired during the duration of the low-speed movement indicates that the object is approaching or moving away from the vehicle, and the absolute value of the speed signal is less than or equal to the speed threshold. The speed signal acquired during the duration of the moving-away action indicates that the object is moving away from the vehicle at a speed greater than the speed threshold.

8. The kick sensor according to claim 6, characterized in that, It also includes a low-pass filter for detecting signals related to stationary objects. The control unit also includes a preprocessing unit that subtracts the signal related to the stationary object obtained by the low-pass filter from the received signal of the radar, thereby obtaining a signal containing the signal related to the low-speed movement.

9. A method for detecting kicking motion based on a kicking sensor, the kicking sensor comprising: The sensing unit, installed in the vehicle, is used to detect objects. as well as The control unit determines the movement of the object based on the detection results of the sensor unit. The kicking motion detection method is characterized by the following steps: Based on the detection results of the sensor, the approaching action of the object to the sensor, the moving action of the object away from the sensor, and the low-speed action between the approaching action and the moving action are extracted; Compare the characteristics of the low-speed movement with the characteristics of the approaching movement and the moving away movement; and Based on the comparison results, the continuity between the low-speed action, the approaching action, and the moving away action is determined, and it is determined whether a kicking action has been performed.

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