Vehicle-mounted air conditioner dynamic avoidance air supply method based on human body posture recognition

Abstract

The invention discloses a vehicle-mounted air conditioner dynamic avoidance air supply method based on human body posture recognition, and relates to the technical field of intelligent vehicle-mounted air conditioners and man-machine interaction, and the method comprises the steps that human body posture data of passengers are obtained and fused, and a three-dimensional posture model containing key point coordinates is constructed; recognizing a head key point and a hand key point based on the three-dimensional attitude model, constructing a head protection sphere by taking the head key point as a sphere center, and constructing a hand operation forbidden zone by taking a steering wheel geometric center; and a cubic Bezier curve is adopted to plan a streaming path, the angle combination of the piezoelectric ceramic units in the shutter matrix is calculated, and dynamic avoidance air supply control of the vehicle-mounted air conditioner is carried out. Real-time and high-precision dynamic avoiding air supply capacity is brought to the vehicle-mounted air conditioner, compared with a traditional method, the air feeling comfort level and operation safety of passengers are remarkably improved, and discomfort or interference caused by direct airflow is effectively prevented.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of intelligent vehicle air conditioning and human-computer interaction, and particularly to a vehicle air conditioning dynamic avoidance air supply method based on human body posture recognition. BACKGROUND

[0002] In recent years, with the rapid development of intelligent networking and artificial intelligence technology, the vehicle air conditioning system is gradually evolving towards individualization and intelligence from traditional directional air blowing and constant air volume control. There are numerous air conditioning comfort adjustment schemes based on sensor fusion, which can realize real-time sensing and active adjustment of the vehicle interior environment parameters through temperature and humidity sensing, CO2 concentration monitoring, and facial recognition technology. In addition, human body posture recognition technology has made significant breakthroughs in the field of computer vision. Depth cameras, TOF sensors, and multi-modal fusion algorithms make high-precision three-dimensional posture modeling possible. By extracting key point coordinates such as head, hand, and torso, researchers can track human movements within millimeter accuracy, and then apply it to assisted driving, fatigue detection, and vehicle human-computer interaction. However, the deep coupling of human body posture recognition and vehicle air conditioning system to achieve dynamic avoidance and precise air supply is still in the theoretical exploration and engineering testing stage.

[0003] Most existing vehicle air conditioning adjustment methods are based on preset air direction or manual adjustment, which cannot dynamically avoid the real-time changes of the passenger's posture, resulting in discomfort when the airflow directly hits the head or hands. Some intelligent air conditioners can achieve face tracking air supply, but are limited to two-dimensional adjustment, ignoring the constraints of three-dimensional passenger posture and surrounding interactive areas. In addition, current louver air direction devices or airflow control units often use mechanical stepping motors, which have limited adjustment accuracy and response speed, and are not sufficient to meet the frequent iteration of path planning and boundary avoidance requirements. The scheme based on large-scale air supply is difficult to balance energy saving and local comfort. The existing technology has obvious bottlenecks in achieving safety and comfort, as there is a lack of effective protection and avoidance mechanism for key body parts such as the head and hands. SUMMARY

[0004] In view of the problems existing in the current vehicle air conditioning dynamic avoidance air supply method based on human body posture recognition, the present application is proposed. Therefore, the problem to be solved by the present application is how to provide a vehicle air conditioning dynamic avoidance air supply method based on human body posture recognition.

[0005] To solve the above technical problems, the present application provides the following technical solutions: In a first aspect, the present application provides a vehicle air conditioning dynamic avoidance air supply method based on human body posture recognition, which includes obtaining human body posture data of a passenger and fusing to construct a three-dimensional posture model containing key point coordinates. Head key points and hand key points are identified based on a three-dimensional posture model, a head protection sphere is constructed with the head key points as the center, and a hand operation forbidden zone is constructed with the geometric center of the steering wheel; A cubic Bezier curve is used to plan a flow path, the angle combination of the piezoelectric ceramic units in the baffle matrix is calculated, and dynamic avoidance air supply control of the vehicle-mounted air conditioner is performed.

[0006] As a preferred scheme of the vehicle-mounted air conditioner dynamic avoidance air supply method based on human posture recognition, the human posture data includes occupant depth image data and infrared thermal imaging image data.

[0007] As a preferred scheme of the vehicle-mounted air conditioner dynamic avoidance air supply method based on human posture recognition, the human posture data includes occupant depth image data and infrared thermal imaging image data. An occupant depth image is obtained using a TOF camera, a three-dimensional coordinate point cloud is constructed from the depth image, and skeleton key point coordinates are extracted using a human posture estimation algorithm. An infrared thermal imager collects infrared thermal imaging images, each pixel representing the temperature value at the corresponding position, and after radiation correction and environmental temperature compensation, a temperature distribution matrix is obtained. Camera calibration and coordinate mapping are performed, external parameter calibration of the TOF camera and the thermal imager is performed, a rotation matrix and a translation matrix are obtained, and the thermal imaging coordinates are mapped to the corresponding three-dimensional space of the depth image, represented as: ; Wherein: is the coordinate of the pixel point in the infrared thermal imaging image in the three-dimensional space; is the three-dimensional coordinate point corresponding to the TOF point cloud; and are the rotation matrix and translation matrix of the thermal imager relative to the TOF camera, respectively; A fusion data voxel is constructed, the temperature value is mapped to each three-dimensional point, i.e. a temperature attribute is added to each three-dimensional coordinate point to form a four-dimensional voxel data, a three-dimensional posture model is constructed, represented as: ; Wherein: is the three-dimensional posture model, is the key point three-dimensional coordinate; is the skeleton connection pair; is the key point local temperature; is the temperature gradient of the bone segment.

[0008] As a preferred scheme of the vehicle-mounted air conditioner dynamic avoidance air supply method based on human posture recognition, the human posture data includes occupant depth image data and infrared thermal imaging image data. The head key point is determined as the ball center, and the radius increment is calculated according to the local temperature difference gradient, which is represented as: ; ; Wherein: is the head protection sphere radius after increment, is the default head protection sphere radius, is the increment function, is the maximum temperature difference of the head region, is the lower limit threshold of the temperature difference, is the upper limit threshold of the temperature difference, is the lower limit of the radius increment, is the upper limit of the radius increment; The hand operation forbidden zone is constructed based on the geometric center of the steering wheel, including: obtaining the known geometric center of the steering wheel in the vehicle coordinate system, and establishing a small ball for each hand, with the hand key point as the center and the default hand operation radius as the radius.

[0009] As a preferred scheme of the vehicle-mounted air conditioner dynamic avoidance air supply method based on human body posture recognition, wherein: the three cubic Bezier curves are used to plan the flow path, including: The determined head protection sphere is used to describe the path of the airflow from the air outlet to the target point using a cubic Bezier curve, which is represented as: ; ; Wherein: is the path of the airflow from the air outlet to the target point at time , is the air outlet position, is the target point position, and are the Bezier control points, is the ball center of the head protection sphere, is the safety gap.

[0010] As a preferred scheme of the vehicle-mounted air conditioner dynamic avoidance air supply method based on human body posture recognition, wherein: the angle combination of the piezoelectric ceramic unit in the louver matrix is calculated, including: The Bezier curve is divided into several small segments, each segment corresponding to a small airflow direction, and the target local wind vector of each segment is calculated, which is represented as: ; ; Wherein: is the local wind direction, is the The path of the airflow from the air outlet to the target point at the moment, The path of the airflow from the air outlet to the target point at the moment, The path of the airflow from the air outlet to the target point at the moment, The target local wind vector, The local wind speed; According to the calibration coefficient of each unit and the rotatable angle range, the wind direction of all units is superimposed to determine whether the target local wind vector can be reconstructed, which is represented as: ; ; Wherein: The local wind vector of the piezoelectric ceramic unit at the given driving angle, The maximum width calibration coefficient of the piezoelectric ceramic unit, The rotation matrix around the hinge normal of the piezoelectric ceramic unit, The initial orientation unit vector of the piezoelectric ceramic unit, The given driving angle of the piezoelectric ceramic unit at the first segment of the airflow path; segment of the airflow path; A least square optimization problem is established for each segment, and the optimal deflection angle of each piezoelectric ceramic unit in the movable range is obtained by gradient descent method.

[0011] As a preferred scheme of the vehicle-mounted air conditioner dynamic avoidance air supply method based on human body posture recognition, the vehicle-mounted air conditioner dynamic avoidance air supply control comprises: The Bezier path is re-planned in each cycle, and if the curve planning fails or cannot meet the avoidance constraint due to the violent movement of the passenger, the system immediately returns to the default straight blowing mode and starts a new path planning.

[0012] In a second aspect, the present application provides a computer device comprising a memory and a processor, wherein the memory stores a computer program, and wherein the processor implements the steps of the vehicle-mounted air conditioner dynamic avoidance air supply method based on human body posture recognition when executing the computer program.

[0013] In a third aspect, the present application provides a computer readable storage medium having a computer program stored thereon, wherein the computer program implements the steps of the vehicle-mounted air conditioner dynamic avoidance air supply method based on human body posture recognition when executed by a processor.

[0014] The method not only realizes deep perception of the three-dimensional posture and local body surface temperature of the occupant, but also accurately delimits the safety avoidance area of the head and the hand; further combining curve planning and multi-unit air flow inverse solution, real-time and high-precision dynamic avoidance air supply capacity is brought to the vehicle-mounted air conditioner. Compared with the traditional static orientation or two-dimensional tracking air supply, the wind feeling comfort and operation safety of the occupant are significantly improved, discomfort or interference caused by direct air flow is effectively prevented, and the energy efficiency and rapid response characteristics of the system are taken into account, and the comprehensive optimization of safety, comfort and energy efficiency is achieved. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0016] Figure 1 The flowchart of the vehicle-mounted air conditioner dynamic avoidance air supply method based on human body posture recognition. DETAILED DESCRIPTION

[0017] In order to make the above-mentioned purposes, features and advantages of the present application more apparent, the specific embodiments of the present application will be described in detail below with reference to the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should be within the scope of protection of the present application.

[0018] In the following description, many specific details are set forth in order to provide a thorough understanding of the present application, but the present application can also be implemented in other ways different from the description, and those skilled in the art can make similar generalizations without departing from the concept of the present application, therefore the present application is not limited to the specific embodiments disclosed below.

[0019] Secondly, the "one embodiment" or "embodiment" referred to herein means that the specific features, structures or characteristics can be included in at least one implementation of the present application. "In one embodiment" appearing in different places in the specification does not mean the same embodiment, nor does it mean an embodiment that is separate or selectively excluded from other embodiments.

[0020] REFERENCE Figure 1 For the first embodiment of the present application, the embodiment provides a vehicle-mounted air conditioner dynamic avoidance air supply method based on human body posture recognition, comprising: S1: obtaining human body posture data of the occupant and fusing to construct a three-dimensional posture model containing key point coordinates; Specifically, a TOF (Time-of-Flight) camera is used to obtain a passenger depth image, and each pixel point records its depth (z-axis distance) information. A three-dimensional coordinate point cloud is constructed through the depth map, and a human pose estimation algorithm (such as OpenPose3D or MediaPipe) is used to extract the skeletal key point coordinates.

[0021] The thermal imager collects an infrared thermal image, and each pixel represents the temperature value (unit: °C) at the corresponding position. After radiation correction and environmental temperature compensation, a temperature distribution matrix is obtained.

[0022] Camera calibration and coordinate mapping are performed, and the external parameters of the TOF camera and the thermal imager are calibrated to obtain a rotation matrix and a translation matrix, which are used to map the thermal imaging coordinates to the corresponding three-dimensional space of the depth map, represented as: ; Wherein: is the coordinate of the pixel point in the infrared thermal image in the three-dimensional space; is the three-dimensional coordinate point corresponding to the TOF point cloud; and are the rotation matrix and translation matrix of the thermal imager relative to the TOF camera, respectively, which are obtained by calibration.

[0023] A fusion data voxel is constructed, and the temperature value is mapped to each three-dimensional point, i.e. a temperature attribute is added to each three-dimensional coordinate point to form a four-dimensional voxel data.

[0024] A three-dimensional pose model is constructed, a skeleton structure is constructed using human pose estimation key points, local temperature difference anomaly detection is performed, and a local area (such as a sphere for the head and a cylinder for the arm) is constructed around each skeletal segment. The temperature distribution in this area is analyzed by gradient analysis; if there is a significant temperature difference gradient (such as a shoulder gradient ≤ 0.3°C / cm), it is determined to be a thick clothing area, which can be used to adaptively adjust the size of the protection zone. The final output model is in the form of: ; Wherein: is a three-dimensional pose model, is a three-dimensional coordinate of a skeletal key point; is a skeleton connection pair; is a local temperature of a key point; is the temperature gradient of a skeletal segment.

[0025] S2: Identify the head key point and the hand key point based on the three-dimensional pose model, construct a head protection sphere with the head key point as the sphere center, and construct a hand operation forbidden zone with the geometric center of the steering wheel as the center; Specifically, input the key point set of the three-dimensional posture model, preset parameters, default head protection sphere radius, temperature difference compensation radius increment, steering wheel geometric center coordinates, and hand operation restricted area radius; read the coordinates of the head and hand key points from the three-dimensional posture model.

[0026] Construct a head protection sphere, determine the key point of the head as the center of the sphere, and calculate the radius increment based on the local temperature gradient, which is expressed as: ; ; in: is the radius of the head protection sphere after increment, is the default head protection sphere radius, is the increment function, is the maximum temperature difference in the head area, is the lower limit threshold of temperature difference, is the upper temperature difference threshold, is the lower limit of the radius increment, The upper limit of the radius increment.

[0027] Construct a restricted area for hand operation, obtain the known geometric center of the steering wheel in the vehicle coordinate system, and create a small sphere for each hand, with the center as the hand key point and the radius as the default hand operation radius.

[0028] When the wind path or movable parts enter the protective sphere or hand restricted area, avoidance or wind direction adjustment is triggered.

[0029] S3: Use cubic Bezier curves to plan the flow path, calculate the angle combination of piezoelectric ceramic units in the louver matrix, and perform dynamic avoidance air supply control for the vehicle air conditioner.

[0030] Specifically, a cubic Bezier curve is used to plan the flow path. Using the tangent plane of the head protection sphere as a constraint, the angle combination of the 128 piezoelectric ceramic units in the louver matrix is ​​calculated to ensure that the airflow trajectory maintains a minimum safe distance of 3cm from the boundary of the avoidance space. When the infant is detected to be sleeping (surface temperature fluctuation <0.1°C / min), the breeze surround mode is activated, locking the wind speed limit to 1.8m / s.

[0031] Based on the determined head protection sphere, a safety gap (e.g., 3cm) is added to the head protection sphere as the avoidance boundary. A cubic Bezier curve is used to describe the path of the airflow from the air outlet to the target point. The curve is determined by four control points: the starting point, the end point, and two intermediate control points, expressed as: ; ; in: for The path of the airflow from the air outlet to the target point at any moment, is the air outlet position, is the target point position, and are Bezier control points, To protect the center of the sphere for the head, For safety clearance; Through numerical optimization algorithms, a set of intermediate control points is found to make the Bezier curve smooth and close to a straight path, ensuring that the airflow is as straight as possible and does not invade the limited area, while ensuring that the distance between the curve point and the center of the protection sphere is not less than . After the optimization is completed, the curve is divided into several small segments, each of which corresponds to a small airflow direction. For each segment, the direction of the line between the starting point and the end point of the segment is calculated as the local wind direction unit vector, and the wind speed is assigned to it according to the predetermined local wind speed scale to obtain the target local wind vector, which is expressed as: ; ; in: is the local wind direction, for The path of the airflow from the air outlet to the target point at any moment, for The path of the airflow from the air outlet to the target point at any moment, is the target local wind vector, is the local wind speed; These segmented target wind vectors are mapped onto the piezoelectric ceramic units of the louver matrix. Based on the calibration coefficient of each unit and the rotatable angle range, it is assumed that each unit can contribute a local wind direction at a given deflection angle. The wind directions of all units are then approximated by linear superposition to see if the required target local wind vector can be reconstructed, expressed as: ; ; in: For a given drive angle The local wind vector of the piezoelectric ceramic unit is is the maximum width calibration coefficient of the piezoelectric ceramic unit, is the rotation matrix around the hinge normal of the piezoelectric ceramic unit, is the initial orientation unit vector of the piezoelectric ceramic unit, The airflow path The given driving angle of the piezoelectric ceramic unit during the segment; Thus, a least-squares optimization problem is established for each segment: find a set of deflection angles within the movable range of each piezoelectric ceramic unit that makes the sum of all unit wind direction vectors closest to the target vector, quickly solved by gradient descent.

[0032] In each cycle, the latest head key points are obtained, the Bezier path is re-planned, the target wind vector is recalculated, and the piezoelectric ceramic unit angle is re-solved. If the curve planning fails or cannot meet the avoidance constraint due to the passenger's violent movement, the system will immediately fall back to the default straight blowing mode and start a new path planning.

[0033] The embodiment also provides a computer device suitable for the case of the vehicle-mounted air conditioner dynamic avoidance air supply method based on human body posture recognition, including a memory and a processor; the memory is used to store computer executable instructions, and the processor is used to execute the computer executable instructions to implement all or part of steps of the method described in the embodiment of the application.

[0034] The embodiment also provides a storage medium having a computer program stored thereon, and the computer program is executed by a processor to execute the method in any optional implementation manner of the above-mentioned embodiment. The storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as a static random access memory (SRAM), an electrically erasable programmable read-only memory (EEPROM), an erasable programmable read-only memory (EPROM), a programmable read-only memory (PROM), a read-only memory (ROM), a magnetic storage, a flash memory, a magnetic disk or an optical disk.

[0035] The storage medium proposed in the embodiment belongs to the same inventive concept as the data storage method proposed in the above-mentioned embodiment, and the technical details not described in the embodiment can be referred to the above-mentioned embodiment, and the embodiment has the same beneficial effects as the above-mentioned embodiment.

[0036] In summary, the method not only realizes the depth perception of the three-dimensional posture and local body surface temperature of the occupant, but also accurately delimits the safety avoidance area of the head and hands. Further combined with curve planning and multi-unit air flow inverse solution, it brings real-time and high-precision dynamic avoidance air supply capability to the vehicle air conditioner. Compared with the traditional static directional or two-dimensional tracking air supply, it significantly improves the air feeling comfort and operation safety of the occupant, effectively prevents discomfort or interference caused by direct air flow, and at the same time, takes into account the energy efficiency and rapid response characteristics of the system, achieving the comprehensive optimization of safety, comfort and energy efficiency.

[0037] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and are not limiting. Although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present application can be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present application, which should be covered in the scope of the claims of the present application.

Claims

1. A dynamic avoidance air supply method for vehicle air conditioning based on human posture recognition, characterized by: include, Obtain and fuse the occupant's body posture data to construct a three-dimensional posture model containing key point coordinates; Based on the 3D posture model, the key points of the head and hands are identified. A head protection sphere is constructed with the key points of the head as the center of the sphere, and a hand operation restricted area is constructed with the geometric center of the steering wheel. The cubic Bezier curve is used to plan the flow path, and the angle combination of the piezoelectric ceramic units in the louver matrix is ​​calculated to perform dynamic avoidance air supply control for the vehicle air conditioner.

2. The method for dynamic avoidance air supply of vehicle air conditioner based on human posture recognition according to claim 1, characterized in that: The human body posture data includes occupant depth image data and infrared thermal imaging image data.

3. The method for dynamic avoidance air supply of vehicle air conditioner based on human posture recognition according to claim 2, characterized in that: The constructing of a three-dimensional posture model including coordinates of skeleton key points includes: Use a TOF camera to obtain a depth image of the occupant, construct a 3D coordinate point cloud from the depth image, and combine it with a human posture estimation algorithm to extract the coordinates of key skeletal points; The thermal imager collects infrared thermal imaging images. Each pixel represents the temperature value at the corresponding position. After emissivity correction and ambient temperature compensation, the temperature distribution matrix is ​​obtained. Perform camera calibration and coordinate mapping, perform external parameter calibration on the TOF camera and thermal imager, obtain the rotation matrix and translation matrix, and map the thermal imaging coordinates to the three-dimensional space corresponding to the depth map, which is expressed as: ； in: is the coordinate of the pixel point in the infrared thermal imaging image in three-dimensional space; is the three-dimensional coordinate point corresponding to the TOF point cloud; and They are the rotation matrix and translation matrix of the thermal imager relative to the TOF camera; Construct fused volume data voxels and map the temperature value to each 3D point, that is, attach the temperature attribute to each 3D coordinate point to form 4D voxel data and construct a 3D posture model, which can be expressed as: ； in: is a three-dimensional posture model, is the three-dimensional coordinate of the key point; is the skeleton connection pair; is the local temperature of the key point; is the temperature gradient of the bone segment.

4. The method for dynamic avoidance air supply of vehicle air conditioner based on human posture recognition as claimed in claim 3, characterized in that: The construction of the head protection sphere with the key point of the head as the sphere center includes: The key point of the head is determined to be the center of the sphere, and the radius increment is calculated based on the local temperature gradient, which is expressed as: ； ； in: is the radius of the head protection sphere after increment, is the default head protection sphere radius, is the increment function, is the maximum temperature difference in the head area, is the lower limit threshold of temperature difference, is the upper temperature difference threshold, is the lower limit of the radius increment, is the upper limit of the radius increment; The construction of the hand operation restricted area based on the geometric center of the steering wheel includes: obtaining the known geometric center of the steering wheel in the vehicle coordinate system, and establishing a small ball for each hand, with the center being the hand key point and the radius being the default hand operation radius.

5. The method for dynamic avoidance air supply of vehicle air conditioner based on human posture recognition according to claim 4, characterized in that: The method of planning the flow path by using a cubic Bezier curve includes: Based on the determined head protection sphere, a cubic Bezier curve is used to describe the path of the airflow from the air outlet to the target point, which is expressed as: ； ； in: for The path of the airflow from the air outlet to the target point at any moment, is the air outlet position, is the target point position, and are Bezier control points, To protect the center of the sphere for the head, For safety clearance.

6. The method for dynamic avoidance air supply of vehicle air conditioner based on human posture recognition according to claim 5, characterized in that: The calculation of the angle combination of the piezoelectric ceramic units in the louver matrix includes: Divide the Bezier curve into several small segments, each segment corresponds to a small airflow direction, and calculate the target local wind vector of each segment, which is expressed as: ； ； in: is the local wind direction, for The path of the airflow from the air outlet to the target point at any moment, for The path of the airflow from the air outlet to the target point at any moment, is the target local wind vector, is the local wind speed; According to the calibration coefficient and rotatable angle range of each unit, the wind directions of all units are superimposed to determine whether the required target local wind vector can be reconstructed, which is expressed as: ； ； in: For a given drive angle The local wind vector of the piezoelectric ceramic unit is is the maximum width calibration coefficient of the piezoelectric ceramic unit, is the rotation matrix around the hinge normal of the piezoelectric ceramic unit, is the initial orientation unit vector of the piezoelectric ceramic unit, The airflow path The given driving angle of the piezoelectric ceramic unit during the segment; A least squares optimization problem is established for each segment, and the optimal deflection angle of each piezoelectric ceramic unit within the movable range is obtained by the gradient descent method.

7. The method for dynamic avoidance air supply of vehicle air conditioner based on human posture recognition according to claim 6, characterized in that: The dynamic avoidance air supply control of the vehicle air conditioner includes: The Bezier path is replanned in each cycle. If the occupant moves violently, causing the curve planning to fail or the avoidance constraints to be met, the system immediately returns to the default straight-through mode and starts a new path planning.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the vehicle air conditioning dynamic avoidance air supply method based on human posture recognition according to any one of claims 1 to 7 are implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the vehicle air conditioning dynamic avoidance air supply method based on human posture recognition according to any one of claims 1 to 7 are implemented.

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