KR20220095734A - Radar apparatus and method for detecting dynamic object in vehicle - Google Patents

Abstract

A radar apparatus for detecting a dynamic object in a vehicle includes: a transmission unit transmitting a radar signal to a rear seat region of a vehicle by using a radar sensor installed in the vehicle; a reception unit receiving the radar signal reflected by an object in the rear seat region; a bio-signal extraction signal extracting a bio-signal for each seat of the rear seat region based on the received radar signal; and an object detection unit detecting a dynamic object located in the rear seat region based on the extracted bio-signal.

Description

RADAR APPARATUS AND METHOD FOR DETECTING DYNAMIC OBJECT IN VEHICLE

The present invention relates to a radar device and method for detecting a dynamic object in a vehicle.

Recent vehicles are emerging as a social problem as infants or pets left in the vehicle are more likely to suffocate. In order to prevent this problem of suffocation in vehicles, the Euro NCAP (New Car Assessment Program), a car crash testing agency, gave a 5 star rating to a function that detects a biosignal and notifies if there is a living organism after the vehicle is turned off. It was designated as mandatory for receiving.

To this end, automobile manufacturers have begun to mount a Rear Occupant Alert (ROA) function using an ultrasonic sensor or the like in the vehicle.

Rear seat passenger notification refers to a technology that prevents accidents from occurring by detecting whether a child is in the vehicle and sending an alarm sound and message when the driver gets off the vehicle. -0031410 discloses a method for notifying a rear-seat passenger and a vehicle fob device using the same.

However, since the conventional rear seat passenger notification is detected only when there is a movement of a living organism in the rear seat of the vehicle, if the infant is sleeping, the movement of the living organism cannot be detected and thus the presence of the infant cannot be detected. In addition, the sensors for the rear seat passenger notification are respectively mounted on the ceiling of the rear seat of the vehicle to face each rear seat, so that the size of the sensor is large and the aesthetics of the vehicle is not good. In addition, in addition to the sensor for detecting living things, it is possible to detect whether a passenger is seated in the seat by using a pressure sensor, but it is inconvenient that a false alarm is generated when a heavy object, not a living thing, is placed on the seat of the vehicle in the rear seat area of the vehicle. ham exists

An object of the present invention is to provide a dynamic object detection apparatus and method for transmitting a radar signal toward a rear seat area of a vehicle using a radar sensor installed in a vehicle and receiving a radar signal reflected by an object within the rear seat area.

An object of the present invention is to provide an apparatus and method for extracting a biosignal for each seat in the rear seat area based on a radar signal and detecting a dynamic object located in the rear seat area based on the extracted biosignal.

However, the technical problems to be achieved by the present embodiment are not limited to the technical problems described above, and other technical problems may exist.

As a means for achieving the above-described technical problem, an embodiment of the present invention provides a transmitter that transmits a radar signal toward the rear seat area of the vehicle using a radar sensor installed in the vehicle, and is reflected by an object in the rear seat area A receiver for receiving a radar signal, a biosignal extractor for extracting biosignals for each seat in the rear seat area based on the received radar signal, and a dynamic object located in the rear seat area based on the extracted biosignal to detect It is possible to provide a dynamic object detection radar device including an object detection unit.

Another embodiment of the present invention includes the steps of transmitting a radar signal toward a rear seat area of a vehicle using a radar sensor installed in the vehicle, receiving a radar signal reflected by an object in the rear seat area, and the received radar It is possible to provide a dynamic object detection method comprising extracting a biosignal for each seat of the rear seat area based on a signal and detecting a dynamic object located in the rear seat area based on the extracted biosignal.

The above-described problem solving means are merely exemplary, and should not be construed as limiting the present invention. In addition to the exemplary embodiments described above, there may be additional embodiments described in the drawings and detailed description.

According to any one of the means for solving the problems of the present invention described above, by using a radar sensor installed in the vehicle to transmit a radar signal toward the rear seat area of the vehicle and receive a radar signal reflected by an object located in the rear seat area, the radar A dynamic object detection apparatus and method for detecting a dynamic object located in the rear seat region by extracting a biosignal for each seat in the rear seat region based on the signal may be provided.

Since the radar sensor is installed in either the side pillar located between the interior front door and the interior rear door of the vehicle or the rear pillar located between the interior rear door and the interior rear window of the vehicle, it is easy to distinguish objects by distance resolution, It is possible to provide an apparatus and method for detecting a dynamic object capable of increasing stability in extraction of biosignals.

By using the high-resolution radar sensor, it is possible to provide an apparatus and method for detecting whether a dynamic object exists in the rear seat area of a vehicle based on a radar signal even when there is no movement of the object located in the rear seat area.

The conventional radar sensor for object detection in the vehicle is installed in the center area of the ceiling area in the vehicle to direct each seat in the rear seat area, and as a result, the calculation becomes complicated as biosignals are received through a plurality of channels. , but there was a disadvantage that the size of the sensor was large and it was not aesthetically good, but the radar sensor of the present application is located at a position corresponding to a side pillar or a rear pillar in the vehicle (specifically, a position corresponding to the space between each pillar and the cover of the corresponding pillar) or A dynamic object that does not impair the aesthetics of the interior of the vehicle by being installed in the peripheral region (specifically, the position corresponding to the space between the ceiling and the ceiling cover of the peripheral region) that is biased to the side outside the central region among the ceiling regions in the vehicle A detection apparatus and method may be provided.

When a blanket is placed on an infant to put an infant located in the back seat area to sleep, other sensors such as a camera cannot penetrate the blanket and the like, so the baby cannot be detected. It is possible to provide an apparatus and method for detecting a dynamic object that can do this.

1 is a block diagram of an apparatus for detecting a dynamic object according to an embodiment of the present invention.
2A and 2B are exemplary views for explaining a process of transmitting a radar signal to each seat in the rear seat area of a vehicle based on an installation position of a radar sensor according to an embodiment of the present invention.
3A and 3B are exemplary views for explaining a process of setting a frequency range for each seat in the rear seat area according to an embodiment of the present invention.
4A and 4B are exemplary views for explaining a process of extracting a biosignal based on a radar signal according to an embodiment of the present invention.
5 is an exemplary view illustrating a change in a biosignal according to whether a dynamic object is detected for each seat in the rear seat area of a vehicle according to an embodiment of the present invention.
6 is a flowchart of a method for detecting a dynamic object in a vehicle in the apparatus for detecting a dynamic object according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art can easily implement them. However, the present invention may be embodied in several different forms and is not limited to the embodiments described herein. And in order to clearly explain the present invention in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification.

Throughout the specification, when a part is "connected" with another part, this includes not only the case of being "directly connected" but also the case of being "electrically connected" with another element interposed therebetween. . In addition, when a part "includes" a certain component, it means that other components may be further included, rather than excluding other components, unless otherwise stated, and one or more other features However, it is to be understood that the existence or addition of numbers, steps, operations, components, parts, or combinations thereof is not precluded in advance.

In this specification, a "part" includes a unit realized by hardware, a unit realized by software, and a unit realized using both. In addition, one unit may be implemented using two or more hardware, and two or more units may be implemented by one hardware.

Some of the operations or functions described as being performed by the terminal or device in this specification may be instead performed by a server connected to the terminal or device. Similarly, some of the operations or functions described as being performed by the server may also be performed in a terminal or device connected to the server.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram of an apparatus for detecting a dynamic object according to an embodiment of the present invention. Referring to FIG. 1 , the dynamic object detection apparatus 100 may include a transmitter 110 , a receiver 120 , a biosignal extractor 130 , an object detector 140 , and a detection information transmitter 150 . have.

The transmitter 110 may transmit a radar signal toward the rear seat area of the vehicle using a radar sensor installed in the vehicle. For example, the radar sensor may be a Frequency Modulated Continuous Wave Radar (FMCW) having a wide frequency bandwidth of 60 GHz. The FMCW radar may be a radar having improved ranging capability by modulating a frequency. As another example, the radar sensor may have a frequency bandwidth of 6 GHz, and in this case, may have a range resolution of 2.5 cm.

2A and 2B are exemplary views for explaining a process of transmitting a radar signal to each seat in the rear seat area of a vehicle based on an installation position of a radar sensor according to an embodiment of the present invention.

In general, vehicle 200 includes a plurality of pillars. The pillar means a pillar of the vehicle body, and the pillar is located in the middle between the door and the ceiling of the vehicle, thereby increasing the strength of the vehicle.

The vehicle 200 includes a front pillar located between the front window and the side window, a side pillar located between the front door and the rear door, and a rear pillar between the rear door and the rear window.

Referring to FIG. 2A , the radar sensor 210 may be installed on the side pillar 201 positioned between the inner front door and the inner rear door of the vehicle 200 .

The transmitter 110 may transmit a radar signal for each seat of the rear seat area 220 of the vehicle 200 using the radar sensor 210 installed on the side pillar 201 of the vehicle 200 . For example, the transmission unit 110 uses the radar sensor 210 installed on the side pillar 201 of the vehicle 200 to include the first rear seat 221 and the second in the rear seat area 220 of the vehicle 200 . A radar signal may be transmitted to the second rear seat 222 and the third rear seat 223 .

Referring to FIG. 2B , the radar sensor 210 may be installed in the rear pillar 202 positioned between the inner rear door and the inner rear window of the vehicle 200 .

The transmitter 110 may transmit a radar signal for each seat of the rear seat area 220 of the vehicle 200 using the radar sensor 210 installed on the rear pillar 202 of the vehicle 200 . For example, the transmission unit 110 uses the radar sensor 210 installed on the rear pillar 202 of the vehicle 200 to include the first rear seat 221 and the second in the rear seat region 220 of the vehicle 200 . A radar signal may be transmitted to the second rear seat 222 and the third rear seat 223 .

A conventional radar sensor for detecting objects in a vehicle is mainly installed in a central area close to a rear seat area among a ceiling area in a vehicle. The conventional radar sensor was installed to face a plurality of seats in the rear seat area, and had a disadvantage in that the size of the radar sensor was large and not good in appearance.

However, in the present application, as the radar sensor 210 is installed on the side other than the center of the vehicle 200 , the installation position of the radar sensor 210 is biased toward the side rather than the center of the vehicle 200 , so the object by distance resolution It can provide advantages of easy detection and high stability when biosignals are extracted. That is, in the present invention, between the radar sensor 210 installed on the side pillar 201 or the rear pillar 202 (specifically, a position corresponding to the space between each pillar and the cover of the corresponding pillar) and each rear seat area 220 . Since the distance is different, it is possible to classify the radar signal corresponding to each seat according to the distance, which makes it possible to determine the existence of an object for each seat.

If the airbag is built in the side pillar 201 or the rear pillar 202 of the vehicle 200 , the radar sensor 210 is biased toward the outside of the central area among the ceiling areas in the vehicle in the rear seat area of the vehicle 200 . It may be installed in a peripheral area (specifically, a location corresponding to a space between the ceiling of the corresponding peripheral area and the cover of the ceiling). Here, the radar sensor 210 can pass through the material of the cover of the side pillar 201 or the rear pillar 202 of the vehicle 200 or the material of the ceiling cover, so that it can be installed without any difference in appearance. can do. In addition, in the present invention, since the distance between the radar sensor 210 installed in the peripheral area skewed to the side outside the central area among the ceiling area of the vehicle and each rear seat area 220 is different, the radar signal corresponding to each seat is classified according to the distance. It can be done, and this makes it possible to judge the existence of an object for each seat.

Returning to FIG. 1 again, the receiver 120 may receive a radar signal reflected by an object in the rear seat area.

The receiver 120 may receive a radar signal reflected for each seat in the rear seat area. For example, when the rear seat area consists of three seats, the receiver 120 may receive a radar signal reflected from each of the first rear seat, the second rear seat, and the third rear seat.

The biosignal extractor 130 may derive different distance values for each seat in the rear seat area based on the radar signal.

The biosignal extractor 130 may set a frequency range for each seat in the rear seat area based on the derived distance value. The process of setting the frequency range for each seat in the rear seat area will be described in detail with reference to FIGS. 3A and 3B .

3A and 3B are exemplary views for explaining a process of setting a frequency range for each seat in the rear seat area according to an embodiment of the present invention.

Referring to FIG. 3A , the receiver 120 may receive the radar signal 300 reflected by the object in the rear seat area.

Referring to FIG. 3B , the biosignal extractor 130 may derive different distance values for each seat in the rear seat region based on the radar signal, and set a frequency range for each seat in the rear seat region based on the derived distance value. .

For example, if the radar sensor is installed on the side pillar of the vehicle and the rear seat area is composed of two seats, the biosignal extractor 130 may be configured to generate the shortest distance from the side pillar of the rear seat area, for example, 0 to A distance value of the first rear seat located at a distance of 0.5 m 310 may be derived as '1', and a frequency range may be set based on the distance value of the first rear seat. In addition, the biosignal extractor 130 sets the distance value of the second rear seat region located at a distance of 0.5 to 1 m (320), for example, corresponding to the next seat of the first rear seat from the side pillar in the rear seat region to '2'. , and the frequency range can be set based on the distance value of the second rear seat.

Returning to FIG. 1 , the object detector 140 may determine the object as either a static object or a dynamic object based on a change in the signal amplitude of the radar signal. For example, the object detector 140 may determine whether the object is a static object, such as a bag, umbrella, or luggage, or a dynamic object, such as an adult, baby, or puppy, based on a change in the signal size of the radar signal.

The biosignal extractor 130 may extract vital signs for each seat in the rear seat area based on the received radar signal. The process of extracting the biosignal will be described, for example, through Equations 1 to 7 below.

Referring to Equation 1, when the biosignal extractor 130 mixes the transmitted and received radar signals and applies a low-pass filter, the instantaneous frequency (IF) signal x( t, n) can be derived. x(t, n) may be largely composed of f _r which is a beat frequency, M(t, r) which is a magnitude, and P(t, r) which is a phase, and t is a scan Scan index, n is the sample index of the chirp, r is the detection range, S is the rate at which the chirp increases, the slope of the chirp, c is the speed of light, F _s may represent a sampling frequency. Specifically, fr corresponds to the distance of the object, M(t, r) is the output of the reflected signal of the object located at r, and P(t, r) is the time delay of the radar signal reflected at r.

Referring to Equation 2, the biosignal extractor 130 may apply a discrete Fourier transform.

,(

)에서, BW(Bandwidth)는 대역폭이고, N은 단일 칩의 총 샘플 수를 의미할 수 있다. Referring to Equation 3, the biosignal extractor 130 derives M(t, r _k ) from x(t, n) by focusing on the size M(t, r) for the analysis of the radar signal. can do. here,

,(

), BW (Bandwidth) is the bandwidth, and N may mean the total number of samples of a single chip.

Referring to Equation 4, M(t, r _k ) may be modeled by applying the radar equation. Here, M ₀ may mean the power of the transmitted radar signal.

Referring to Equation 5, if it is assumed that the object in the r _k range vibrates with a small displacement Δ(t), M(t, r _k ) in Equation 4 can be modified by applying R _k (t) instead of rk. can

),

는 테일러 급수 전개(the Taylor series expansion)에 의해 근사될 수 있다. Referring to Equation 6, since Δ(t) is very smaller than r _k , (

),

can be approximated by the Taylor series expansion.

은 DC항이 M(t, rk)에서 감산된 결과로, △(t)의 평균이 0이라고 가정하면, (mean(△(t)) = 0),

의 관계가 도출될 수 있다. Referring to Equation 7,

is the result of subtracting the DC term from M(t, rk). Assuming that the mean of Δ(t) is 0, (mean(Δ(t)) = 0),

relationship can be derived.

는 작은 변위 △(t)에 비례하므로,

를 통해 생체 신호를 추출할 수 있다.For the measurement of vital signs, Δ(t) is a small displacement caused by respiration and heartbeat,

is proportional to the small displacement Δ(t), so

biosignals can be extracted through

The biosignal extractor 130 may extract a biosignal corresponding to a frequency range set for each seat in the rear seat area based on the radar signal. Here, the biosignal extractor 130 may extract at least one biosignal based on the radar signal and the distance value, and extract the final biosignal through phase analysis of the at least one biosignal. have.

For example, the biosignal extractor 130 may extract a biosignal corresponding to a breathing frequency range (eg, 0.1 to 0.4Hz) from a frequency range set for each seat in the rear seat area based on the radar signal.

As another example, the biosignal extractor 130 may extract a biosignal corresponding to the beating frequency range from the beating frequency range (eg, 0.8 to 1.7Hz) set for each seat in the rear seat area based on the radar signal. have. The process of extracting the biosignal based on the radar signal will be described in detail with reference to FIGS. 4A and 4B .

4A and 4B are exemplary views for explaining a process of extracting a biosignal based on a radar signal according to an embodiment of the present invention.

Referring to FIG. 4A , when a dynamic object does not exist in the rear seat region of the vehicle, the magnitude of the radar signal 400 is greatly changed in a time domain 401 and a frequency domain 402 . It can be seen that the display is displayed at a flat frequency.

Referring to FIG. 4B , when a dynamic object exists in the rear seat region of the vehicle, the radar signal 410 is in a range of 0.8 to 1.2 m according to time in a time domain 411 and a frequency domain 412 . , and at 1.05 m, it can be seen that periodic size fluctuations appear. Here, the periodic magnitude change may include a respiration signal (eg, a peak of 0.2 Hz) and a beating range (eg, a peak of 1.3 Hz).

Here, the size change in the time domain and the frequency domain may be caused by the physiological movement of the dynamic object.

Returning to FIG. 1 again, the object detection unit 140 may detect a dynamic object located in the rear seat area based on the extracted biosignal.

When a dynamic object is detected in the rear seat area, the detection information transmitter 150 may transmit detection information on the dynamic object to a vehicle control device (not shown) interworking with the dynamic object detection apparatus 100 . In this case, a voice notification may be output by the vehicle control device (not shown) based on detection information on the dynamic object.

For example, when a 'baby' is detected as a dynamic object in the rear seat area, the detection information transmitting unit 150 transmits the detection information to the vehicle control device (not shown), and through the vehicle control device (not shown). Voice alerts such as ''Please check the back seat' or "The baby is in the back seat" may be output.

5 is an exemplary view illustrating a change in a biosignal according to whether a dynamic object is detected for each seat in the rear seat area of a vehicle according to an embodiment of the present invention.

Referring to FIG. 5 , there is no passenger in the vehicle 500 , the first passenger gets into the vehicle at 30 seconds 501 , and the second passenger gets into the vehicle after the first passenger at 60 seconds At 502 , the second passenger gets off the vehicle at 240 seconds and only the first passenger remains ( 503 ), and the first passenger gets off at 270 seconds and no one remains in the vehicle ( 504 ). Let's assume that is going on.

5 (a) and (b) are graphs showing radar signal values corresponding to distance values detected according to a time sequence from 500 to 504, specifically a graph 510 corresponding to a breathing frequency range and a beat It can be seen that the graph 511 corresponding to the frequency range is shown, and the graph 510 corresponding to the breathing frequency range and the graph 511 corresponding to the beating frequency range are changed according to the passenger's getting on and off.

6 is a flowchart of a method for detecting a dynamic object in a vehicle in the apparatus for detecting a dynamic object according to an embodiment of the present invention. The method of detecting a dynamic object in a vehicle by the dynamic object detecting apparatus 100 illustrated in FIG. 6 includes steps of time-series processing according to the embodiment illustrated in FIGS. 1 to 5B . Therefore, even if omitted below, it is also applied to the dynamic object detecting apparatus 100 according to the embodiment shown in FIGS. 1 to 5B .

In operation S610, the dynamic object detection apparatus 100 may transmit a radar signal toward the rear seat area of the vehicle using a radar sensor installed in the vehicle.

In operation S620, the dynamic object detection apparatus 100 may receive a radar signal reflected by the object in the rear seat area.

In operation S630 , the dynamic object detection apparatus 100 may extract a biosignal for each seat in the rear seat area based on the received radar signal.

In operation S640 , the dynamic object detection apparatus 100 may detect a dynamic object located in the rear seat area based on the extracted biosignal.

In the above description, steps S610 to S640 may be further divided into additional steps or combined into fewer steps, according to an embodiment of the present invention. In addition, some steps may be omitted as needed, and the order between the steps may be switched.

The method for detecting a dynamic object in a vehicle in the dynamic object detection apparatus described with reference to FIGS. 1 to 6 is also implemented in the form of a computer program stored in a medium executed by a computer or a recording medium including instructions executable by the computer. can be In addition, the method of detecting a dynamic object in a vehicle in the dynamic object detection apparatus described with reference to FIGS. 1 to 6 may be implemented in the form of a computer program stored in a medium executed by a computer.

Computer-readable media can be any available media that can be accessed by a computer and includes both volatile and nonvolatile media, removable and non-removable media. Also, computer-readable media may include computer storage media. Computer storage media includes both volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data.

The description of the present invention described above is for illustration, and those of ordinary skill in the art to which the present invention pertains can understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. For example, each component described as a single type may be implemented in a dispersed form, and likewise components described as distributed may also be implemented in a combined form.

The scope of the present invention is indicated by the following claims rather than the above detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be interpreted as being included in the scope of the present invention. do.

100: dynamic object detection device
110: transmitter
120: receiver
130: biosignal extraction unit
140: object detection unit
150: detection information transmission unit

Claims (13)

A radar device for detecting a dynamic object in a vehicle, comprising:
a transmitter configured to transmit a radar signal toward a rear seat area of the vehicle using a radar sensor installed in the vehicle;
a receiver for receiving a radar signal reflected by an object in the rear seat area;
a biosignal extraction unit for extracting biosignals for each seat in the rear seat area based on the received radar signal; and
An object detection unit that detects a dynamic object located in the rear seat area based on the extracted bio-signal
Including, a dynamic object detection radar device.
The method of claim 1,
wherein the radar sensor is installed in either a side pillar located between the interior front door and interior rear door of the vehicle or a rear pillar located between the interior rear door and interior rear window of the vehicle. radar device.
3. The method of claim 2,
The transmitting unit transmits a radar signal for each seat in the rear seat area of the vehicle using the radar sensor installed in any one of a side pillar or a rear pillar of the vehicle,
The receiving unit will receive the radar signal reflected for each seat in the rear seat area, a dynamic object detection radar device.
4. The method of claim 3,
The biosignal extractor is to derive a different distance value for each seat in the rear seat area based on the radar signal, a dynamic object detection radar device.
5. The method of claim 4,
The biosignal extractor sets a frequency range for each seat in the rear seat area based on the derived distance value.
6. The method of claim 5,
The biosignal extracting unit extracts the biosignal corresponding to a frequency range set for each seat in the rear seat area based on the radar signal.
7. The method of claim 6,
The biosignal extraction unit extracts the biosignal corresponding to the breathing frequency range from a frequency range set for each seat in the rear seat area based on the radar signal.
7. The method of claim 6,
The biosignal extracting unit extracts the biosignal corresponding to the heartbeat frequency range from a frequency range set for each seat in the rear seat area based on the radar signal.
5. The method of claim 4,
The biosignal extractor extracts at least one biometric candidate signal based on the radar signal and the distance value;
and extracting a final bio-signal through phase analysis of the at least one bio-candidate signal.
The method of claim 1,
Wherein the object detection unit determines the object as either a static object or the dynamic object based on a change in the signal amplitude of the radar signal, a dynamic object detection radar device.
The method of claim 1,
When the dynamic object is detected in the rear seat area, further comprising a detection information transmission unit for transmitting detection information on the dynamic object to a vehicle control device interworking with the dynamic object detection radar device,
The dynamic object detection radar device of claim 1 , wherein a voice notification is output based on the detection information on the dynamic object by the vehicle control device.
The method of claim 1,
Wherein the radar sensor is installed in a peripheral area that is biased toward the side outside the central area among the ceiling area in the vehicle, the dynamic object detection radar device.
A method for detecting a dynamic object in a vehicle in a dynamic object detection radar device, the method comprising:
transmitting a radar signal toward a rear seat area of the vehicle using a radar sensor installed in the vehicle;
receiving a radar signal reflected by an object in the rear seat area;
extracting biosignals for each seat in the rear seat area based on the received radar signal; and
detecting a dynamic object located in the rear seat area based on the extracted biosignal
Including, a dynamic object detection method.

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