CN112105964B

CN112105964B - Sensor system, air conditioning system, object detection method, and recording medium

Info

Publication number: CN112105964B
Application number: CN201980030894.XA
Authority: CN
Inventors: 岛本延亮; 山中浩
Original assignee: Panasonic Intellectual Property Management Co Ltd
Current assignee: Panasonic Intellectual Property Management Co Ltd
Priority date: 2018-05-16
Filing date: 2019-05-16
Publication date: 2024-07-23
Anticipated expiration: 2039-05-16
Also published as: CN112105964A; JP7228767B2; WO2019221244A1; JPWO2019221244A1

Abstract

The invention provides an object detection system, a sensor system, an air conditioning system, an object detection method and a program capable of enlarging a region of a detectable object. The object detection system (1) is provided with a switching unit (12), a determination unit (11), and a background correction unit (13). A switching unit (12) switches the detection area between a plurality of areas including at least the specific area. A judging unit (11) judges whether or not an object is present in the detection area based on the result of comparing the output data of the temperature sensor (2) for detecting the temperature of the detection area with the background data corresponding to each of the plurality of areas. A background correction unit (13) corrects background data corresponding to a specific region based on the amount of temperature change during the period when the detection region is a region other than the specific region.

Description

Sensor system, air conditioning system, object detection method, and recording medium

Technical Field

The present disclosure relates generally to an object detection system, a sensor system, an air conditioning system, an object detection method, and a program, and more particularly, to an object detection system, a sensor system, an air conditioning system, an object detection method, and a program that detect an object from an output of a temperature sensor.

Background

Patent document 1 describes an air conditioner provided with a human body sensor for detecting the presence of a person in a room and the position of the person in the room. The air conditioner performs control of the fan unit and the like with reference to the presence of the indoor person and the position of the indoor person determined from the detection result (detection signal) of the human body sensor.

For example, the air conditioner can determine the direction of the horizontal wind direction plate based on the detection result of the human body sensor, and can direct the air flow to the indoor person with high accuracy. In addition, according to the motion of the human body sensor, the air flow can also track the movement of indoor personnel, and even if the indoor personnel move, the air flow can accurately reach the indoor personnel. Thus, the indoor person can reliably obtain a cool feeling due to the cooling effect of the airflow.

As such a human body sensor, an object detection system that detects an object (indoor person) in a detection area based on an output of a temperature sensor that detects a temperature of the detection area can be used.

Prior art literature

Patent literature

Patent document 1: japanese patent laid-open No. 2014-126295

Disclosure of Invention

However, in the object detection system described above, the area in which the object can be detected is limited to the angle of view of the temperature sensor, and there is a possibility that the object (indoor person) existing outside the angle of view of the temperature sensor, for example, even indoors, cannot be detected.

The present disclosure has been made in view of the above-described circumstances, and an object thereof is to provide an object detection system, a sensor system, an air conditioning system, an object detection method, and a program capable of expanding a region of a detectable object.

An object detection system according to an aspect of the present disclosure includes a switching unit, a determination unit, and a background correction unit. The switching unit switches the detection area between a plurality of areas including at least a specific area. The determination unit determines whether or not an object is present in the detection region based on a result of comparing output data of a temperature sensor that detects a temperature of the detection region with background data corresponding to each of the plurality of regions. The background correction unit corrects the background data corresponding to the specific region based on the amount of temperature change during the period when the detection region is a region other than the specific region.

A sensor system according to an aspect of the present disclosure includes the object detection system and the temperature sensor.

An air conditioning system according to an aspect of the present disclosure includes the sensor system and an air conditioner that operates based on an output of the determination unit.

An object detection method according to an aspect of the present disclosure includes a switching process, a determination process, and a background correction process. The switching process is a process of switching the detection area between a plurality of areas including at least a specific area. The determination process is a process of determining whether or not an object is present in the detection region based on a result of comparing output data of a temperature sensor that detects a temperature of the detection region with background data corresponding to each of the plurality of regions. The background correction process is a process of correcting the background data corresponding to the specific region based on a temperature change amount during a period in which the detection region is a region other than the specific region.

A program according to an aspect of the present disclosure is a program for causing a computer system to execute the object detection method.

Drawings

Fig. 1 is a block diagram showing the configuration of an object detection system, a sensor system, and an air conditioning system according to embodiment 1.

Fig. 2A and 2B are explanatory views of the operation of the object detection system when an object is present.

Fig. 3A and 3B are explanatory views of the operation in the absence of an object in the object detection system.

Fig. 4A and 4B are explanatory diagrams of the determination processing in the above-described object detection system.

Fig. 5 is a flowchart showing an example of the operation of the object detection system.

Fig. 6 is a flowchart showing an example of the operation of the object detection system.

Fig. 7 is a flowchart showing an example of operations related to the determination processing of the object detection system.

Fig. 8 is an explanatory view of the operation of the object detection system.

Fig. 9 is a flowchart showing an example of the operation of the object detection system according to the comparative example.

Fig. 10A and 10B are explanatory views of the operation of the object detection system.

Fig. 11A to 11C are explanatory views of the operation of the object detection system according to the modification of embodiment 1.

Fig. 12 is an explanatory diagram of the operation of the object detection system according to the 1 st configuration example of embodiment 2.

Fig. 13A is an explanatory diagram of the operation of the object detection system according to the 2 nd configuration example of embodiment 2. Fig. 13B is an explanatory diagram of the operation of the object detection system according to the 3 rd configuration example of embodiment 2.

Detailed Description

(Embodiment 1)

(1) Summary of the inventionsummary

As shown in fig. 1, an object detection system 1 according to the present embodiment constitutes a sensor system 20 together with a temperature sensor 2. In other words, the sensor system 20 according to the present embodiment includes the object detection system 1 and the temperature sensor 2. Further, the sensor system 20 constitutes an air conditioning system 30 together with the air conditioner 3. In other words, the air conditioning system 30 according to the present embodiment includes the sensor system 20 and the air conditioner 3.

The object detection system 1 is a system that detects an object 5 (see fig. 2A) in a detection area 4 (see fig. 2A) based on an output of a temperature sensor 2. In the object detection system 1, the presence or absence of the object 5 in the detection region 4 is determined based on the result of comparing the output data D1 (see fig. 4B) of the temperature sensor 2 with the background data D2 (see fig. 4B). That is, in the object detection system 1, the object 5 is captured as a heat source, and the presence of the object 5 is detected based on the temperature change of the detection region 4 caused by the presence of the object 5 in the detection region 4.

In the air conditioning system 30, for example, the air conditioner 3 operates based on the detection result of the sensor system 20. As an example, the sensor system 20 used in the air conditioning system 30 determines whether or not a person (object 5) is present in the room using the "person" present in the room where the air conditioner 3 is provided as the object 5. When the sensor system 20 determines that no person (object 5) is present in the room, the air conditioner 3 performs control such as switching the operation mode to the power saving mode or stopping the operation.

As shown in fig. 1, the object detection system 1 according to the present embodiment includes a switching unit 12, a judging unit 11, and a background correcting unit 13. The switching unit 12 switches the detection region 4 between a plurality of regions A1 to A3 (see fig. 2A) including at least a specific region. The determination unit 11 determines whether or not the object 5 is present in the detection region 4 based on the result of comparing the output data D1 of the temperature sensor 2 with the background data D2. The temperature sensor 2 detects the temperature of the detection area 4. The background data D2 corresponds to the plurality of areas A1 to A3, respectively. The background correction unit 13 corrects the background data D2 corresponding to the specific region based on the temperature change amount during the period when the detection region 4 is a region other than the specific region.

According to this configuration, since the detection region 4 in which the temperature is detected by the temperature sensor 2 is switched by the switching unit 12 between the plurality of regions A1 to A3, the region of the detectable object 5 can be enlarged as compared with the case where the detection region 4 is fixed. That is, in the object detection system 1 having the above-described configuration, the area in which the object 5 can be detected is not limited to the angle of view of the temperature sensor 2, and the object 5 existing outside the angle of view of the temperature sensor 2 can be detected.

In the object detection system 1 according to the present embodiment, the background correction unit 13 corrects the background data D2 corresponding to the specific region based on the amount of temperature change during the period when the detection region 4 is a region other than the specific region. Thus, although the detection region 4 is switched between the plurality of regions A1 to A3, the reliability (detection accuracy) of the detection of the object 5 in the object detection system 1 is not easily degraded. Details of this are described in the column "(2.3) action".

(2) Details of the

The object detection system 1, the sensor system 20, and the air conditioning system 30 according to the present embodiment will be described in more detail below.

(2.1) Integral Structure

As described above, the air conditioning system 30 according to the present embodiment includes the sensor system 20 and the air conditioner 3. In the present embodiment, the air conditioning system 30 is provided with only one air conditioner 3 as an example, but the present invention is not limited to this example, and the air conditioning system 30 may be provided with a plurality of air conditioners 3.

As described above, the sensor system 20 according to the present embodiment includes the object detection system 1 and the temperature sensor 2. In the present embodiment, the sensor system 20 further includes a driving unit 21. In the present embodiment, all the components of the sensor system 20 are integrated with the air conditioner 3. In other words, all the components of the air conditioning system 30 are provided in the casing 31 of one air conditioner 3 (see fig. 2A).

In the present embodiment, a case where the air conditioning system 30 is introduced into a residential facility such as a single residence or a group residence will be described as an example. Specifically, the housing 31 of the air conditioner 3 is mounted on a wall or ceiling of one living room 40 (see fig. 2A) in a residential facility. In this case, the air conditioner 3 adjusts the temperature, humidity, air cleanliness, air flow, and the like in the living room 40.

The sensor system 20 used in the air conditioning system 30 determines whether or not a person (object 5) is present in the living room 40 by using the "person" present in the living room 40 where the air conditioner 3 is installed as the object 5. That is, the area to be detected by the sensor system 20 for the object 5 and the area to be air-conditioned by the air conditioner 3 are provided in the same space (in the living room 40). Therefore, when the sensor system 20 determines that no person (object 5) is present in the living room 40, the air conditioner 3 performs control such as switching the operation mode to the power saving mode or stopping the operation.

Further, the sensor system 20 according to the present embodiment can recognize not only the presence or absence of a person (object 5) but also the position of the person present in the living room 40 and the number of persons present in the living room 40 (the number of persons). Accordingly, the air conditioner 3 performs control such as changing the direction of the airflow (wind direction) or the air volume according to at least one of the position of the person in the living room 40 and the number of persons.

In the present embodiment, the temperature sensor 2 is an infrared array sensor in which a plurality of sensor elements for detecting infrared rays are two-dimensionally arranged. The term "infrared ray" as used in the present disclosure is at least a ray (hot ray) radiated from a human body, for example, a ray having a wavelength of around 10 μm. Such a temperature sensor 2 outputs a thermal image representing the temperature distribution of a detection region disposed within a given angle of view. The term "thermal image" as used in the present disclosure refers to an image in which a plurality of pixels are arranged in two dimensions with the detected temperatures of the plurality of sensor elements as pixel values. Here, as an example, the temperature sensor 2 is an infrared array sensor in which 64 sensor elements are two-dimensionally arranged in 8in the X-axis direction and 8in the Y-axis direction. Accordingly, the temperature sensor 2 outputs a thermal image having 8 pixels in each of the X-axis direction and the Y-axis direction as output data D1. In other words, the output data D1 is image data including a plurality of pixels each having a temperature value as a pixel value.

Further, the driving unit 21 generates power for moving the temperature sensor 2. In the present embodiment, the driving unit 21 drives the temperature sensor 2 so that the temperature sensor 2 rotates about a rotation axis. The rotation axis of the temperature sensor 2 is, for example, an axis inclined by a predetermined angle in the vertical direction or with respect to the vertical direction. Here, the driving unit 21 changes the orientation of the temperature sensor 2 by rotating the temperature sensor 2, thereby switching the detection region 4 between the plurality of regions A1 to A3 (see fig. 2A). That is, the temperature sensor 2 is configured to be rotatable in the horizontal direction (translational direction) by the driving unit 21, and the detection area 4 is switched according to the orientation of the temperature sensor 2 in the horizontal direction.

The details are described in the column "(2.2) of the structure of the object detection system", but in the present embodiment, the detection region 4 is switched between the 3 regions of the 1 st region A1, the 2 nd region A2, and the 3 rd region A3. Therefore, as shown in fig. 2A, the driving unit 21 reciprocates the temperature sensor 2 within a predetermined rotation angle range, and switches the detection area 4 between the 1 st area A1, the 2 nd area A2, and the 3 rd area A3 by performing the oscillating operation (swinging operation) of the temperature sensor 2. Specifically, the driving unit 21 includes a motor, and causes the temperature sensor 2 to perform a panning operation in accordance with a driving signal from the switching unit 12, which will be described later.

(2.2) Structure of object detection System

Next, the structure of the object detection system 1 will be described.

As shown in fig. 1, the object detection system 1 according to the present embodiment includes a background updating unit 14, an acquiring unit 15, and a background storage unit 16 in addition to a judging unit 11, a switching unit 12, and a background correcting unit 13.

Here, the determination unit 11, the switching unit 12, the background correction unit 13, and the background update unit 14 are implemented by the processing unit 10 having a computer system such as a microcomputer as a main configuration, for example. The processing unit 10 is configured by using a computer system including a processor and a memory as its main configuration, and executes a program recorded in the memory by the processor, thereby realizing the functions of the judging unit 11, the switching unit 12, the background correcting unit 13, and the background updating unit 14. The program may be recorded in advance in a memory, may be provided via an electric communication line such as the internet, or may be provided by recording it on a nonvolatile recording medium such as a memory card.

The processing unit 10 is connected to an acquisition unit 15 and a background storage unit 16. Further, the driving unit 21 and the air conditioner 3 are connected to the processing unit 10. Here, the processing unit 10 and the driving unit 21 or the air conditioner 3 may be connected in a state capable of transmitting information, and are not limited to being directly connected to each other, and may be connected by a communication interface, for example.

As described above, the determination unit 11 determines whether or not the object 5 is present in the detection region 4 based on the comparison result between the output data D1 of the temperature sensor 2 and the background data D2. The "background data" in the present disclosure is data that becomes a reference of the output data D1 when the judgment unit 11 judges whether or not the object 5 is present, and is data that indicates the temperature (thermal image in the present embodiment) of the detection region 4 in the absence of the object 5. In the present embodiment, basically, the output data D1 of the temperature sensor 2 in the case where the object 5 is not present is used as the background data D2.

Here, in the present embodiment, as described above, the output data D1 is image data including a plurality of pixels each having a temperature value as a pixel value. Accordingly, the background data D2 serving as a reference of the output data D1 is also image data including a plurality of pixels each having a temperature value as a pixel value, similarly to the output data D1. Specifically, the background data D2 is a thermal image in which the number of pixels in each of the X-axis direction and the Y-axis direction is 8 pixels.

Further, the term "based on the comparison result" as used in the present disclosure includes not only the case based on the result (difference) of directly comparing the output data D1 and the background data D2 but also the case based on the result of comparing the output data D1 and the background data D2 substantially. That is, the judgment of the presence or absence of the object 5 in the judgment unit 11 is realized by any of the following methods 1 to 3 as an example. The 1 st method is a method of determining the presence or absence of the object 5 based on the result (difference) of directly comparing the output data D1 with the background data D2, and the 2 nd and 3 rd methods are methods of determining the presence or absence of the object 5 without directly comparing the output data D1 with the background data D2.

That is, in the 1 st method, the determination unit 11 calculates difference data by acquiring a difference between the output data D1 and the background data D2, and compares the calculated difference data with a threshold value, thereby determining whether or not the object 5 is present in the detection region 4. In this case, the determination unit 11 determines that the object 5 is "present" based on the difference data exceeding the threshold value. In the present embodiment, it is assumed that the determination unit 11 adopts the 1 st method. Details of the processing related to the determination of the presence or absence of the object 5 in the determination unit 11 are described in the column "(2.3) operation".

In the method 2, the determination unit 11 determines whether or not the object 5 is present in the detection region 4 by comparing the output data D1 with the synthesized data obtained by adding the threshold value to the background data D2 without obtaining the differential data. In this case, the determination unit 11 determines that the object 5 is "present" based on the output data D1 exceeding the synthesized data. In the 3 rd method, the determination unit 11 determines whether or not the object 5 is present in the detection region 4 by comparing the composite data obtained by subtracting the threshold value from the output data D1 with the background data D2 without obtaining the difference data. In this case, the determination unit 11 determines that the object 5 is "present" based on the composite data exceeding the background data D2.

In the present embodiment, the detection area 4 is switched by the switching unit 12 between the plurality of areas A1 to A3, and therefore the background data D2 is set in association with each of the plurality of areas A1 to A3. That is, the background data D2 is set for each region (1 st region A1, 2 nd region A2, or 3 rd region A3) that is a candidate of the detection region 4. Then, the determination unit 11 determines whether or not the object 5 is present in the detection region 4 based on the result of comparing the background data D2 corresponding to the region serving as the detection region 4 among the plurality of regions A1 to A3 with the output data D1 of the temperature sensor 2. That is, when the detection region 4 is the region A1 among the plurality of regions A1 to A3, the determination unit 11 determines whether or not the object 5 is present in the detection region 4 based on the result of comparing the background data D2 corresponding to the region A1 with the output data D1 of the temperature sensor 2.

In the object detection system 1 according to the present embodiment, the object 5 is a moving object. More strictly, the object 5 is a "person" present in the living room 40. Therefore, the determination unit 11 determines that the object 5 is "absent" when the object 5 (person) is not present in the detection area 4, and determines that the object 5 is "present" when the object 5 (person) as a moving object enters the detection area 4 from this state. The object 5 is not limited to a human being as long as it is a moving object, and may be, for example, a small animal.

Here, the determination unit 11 determines whether or not the object 5 is present a plurality of times while the detection area 4 is in the same area. That is, in the present embodiment, the detection region 4 is switched by the switching unit 12 between the plurality of regions A1 to A3. While the detection region 4 is stopped in any one of the plurality of regions A1 to A3, the determination unit 11 performs the determination of the presence or absence of the object 5a plurality of times. In other words, the determination unit 11 performs the determination of the presence or absence of the object 5a plurality of times during the period from the switching of the detection region 4 to the next switching of the detection region 4.

As described above, the switching unit 12 switches the detection area 4 between the plurality of areas A1 to A3 including at least the specific area. That is, the detection region 4 to be detected by the temperature sensor 2 is not fixed but is switched by the switching unit 12. The plurality of regions that become candidates for the detection region 4 include 3 or more regions. In the present embodiment, the 3-zone switching detection zone 4 is assumed to be the 1 st zone A1, the 2 nd zone A2, and the 3 rd zone A3. That is, the plurality of regions that become candidates for the detection region 4 include 3 regions, i.e., the 1 st region A1, the 2 nd region A2, and the 3 rd region A3.

Specifically, as shown in fig. 2A, among 3 areas obtained by dividing the space in the living room 40 into 3 parts in a plan view, the central area becomes the 1 st area A1, the right area becomes the 2 nd area A2, and the left area becomes the 3 rd area A3 as viewed from the temperature sensor 2. Here, as an example, the field angle of the temperature sensor 2 in a plan view is approximately 60 degrees, and a range of approximately 180 degrees centered on the front surface of the air conditioner 3 is equally divided by 3, thereby forming 3 regions, i.e., A1 st region A1, A2 nd region A2, and A3 rd region A3.

In the present embodiment, as described above, the driving unit 21 causes the temperature sensor 2 to perform the panning operation, thereby switching the detection region 4 between the plurality of regions A1 to A3. Accordingly, the switching unit 12 outputs a drive signal to the drive unit 21, and controls the drive unit 21 by the drive signal, thereby switching the detection region 4 between a plurality of (here, 3) regions A1 to A3.

The term "specific region" as used herein is included in the plurality of regions A1 to A3, and is an arbitrary region of interest. In the present embodiment, it is assumed that the 1 st region A1, the 2 nd region A2, and the 3 rd region A3 may be "specific regions". That is, the specific region is not fixed, and varies depending on which of the 1 st region A1, the 2 nd region A2, and the 3 rd region A3 is focused on. For example, when the 1 st area A1 is the "specific area", the 2 nd area A2 and the 3 rd area A3 become areas other than the "specific area". Similarly, when the 2 nd region A2 is the "specific region", the 1 st region A1 and the 3 rd region A3 are the "regions other than the specific region", and when the 3 rd region A3 is the "specific region", the 1 st region A1 and the 2 nd region A2 are the "regions other than the specific region".

Further, in the present embodiment, the switching section 12 performs switching of the detection region 4 at intervals of a given time (for example, several tens seconds to several minutes). That is, the switching of the detection region 4 by the switching section 12 is not continuously performed but is intermittently performed. Specifically, for example, when the driving unit 21 is operated and the switching unit 12 switches the detection area 4 from the 1 st area A1 to the 2 nd area A2, the driving unit 21 is temporarily stopped, and the detection area 4 is temporarily fixed to the 2 nd area A2. When the 2 nd area A2 becomes the detection area 4 and a predetermined time elapses, the driving unit 21 is operated and the switching unit 12 switches the detection area 4 from the 2 nd area A2 to the 1 st area A1. Here, the switching unit 12 temporarily fixes the detection area 4 to the 1 st area A1 by temporarily stopping the driving unit 21. Thus, the driving unit 21 does not always operate, but intermittently operates only when switching the detection area 4. Therefore, compared with a configuration in which the driving unit 21 continuously operates, the amount of power consumption in the driving unit 21 can be reduced, and degradation of the driving unit 21 can be reduced. Further, in the case where the temperature sensor 2 and the object detection system 1 are connected by a cable, the load applied to the cable can be suppressed to be small.

The background correction unit 13 corrects the background data D2 corresponding to the specific region based on the temperature change amount during the period when the detection region 4 is a region other than the specific region. Here, the period in which the detection region 4 is a region other than the specific region is referred to as "1 st period", and the period in which the detection region 4 is a specific region is referred to as "2 nd period". That is, during the 1 st period, the detection area 4 is set to an area other than the specific area, and during the 2 nd period, the detection area 4 is set to the specific area. That is, when the period 1 in which the detection region 4 is a region other than the specific region and the period 2 in which the detection region 4 is a specific region are sequentially switched, the background correction unit 13 corrects the background data D2 used in the period 2 based on the temperature change amount generated in the period 1. In this case, since the background data D2 corresponding to the specific region is not updated in the 1 st period in which the detection region 4 is a region other than the specific region, the background data D2 used in the 2 nd period may deviate due to the temperature change generated in the 1 st period. In order to reduce such a deviation, the background correction unit 13 corrects the background data D2 in the 2 nd period in which the detection region 4 is the specific region, based on the amount of temperature change in the 1 st period in which the detection region 4 is a region other than the specific region.

Further, the "temperature change amount" referred to in the present disclosure means a change amount thereof in the case where the temperature changes in a certain period, for example, the temperature change amount in the 1 st period is a difference between the temperature at the start point of the 1 st period and the temperature at the end point of the 1 st period.

Here, as described above, the specific region is not fixed, and the specific region varies depending on which of the 1 st region A1, the 2 nd region A2, and the 3 rd region A3 is focused on. Thus, for example, when the 1 st area A1 is the "specific area", both the period in which the detection area 4 is the 2 nd area A2 and the period in which the detection area 4 is the 3 rd area A3 become the 1 st period, and the period in which the detection area 4 is the 1 st area A1 becomes the 2 nd period. Similarly, when the 2 nd area A2 is the "specific area", both the period in which the detection area 4 is the 1 st area A1 and the period in which the detection area 4 is the 3 rd area A3 become the 1 st period, and the period in which the detection area 4 is the 2 nd area A2 becomes the 2 nd period. When the 3 rd region A3 is the "specific region", both the period in which the detection region 4 is the 1 st region A1 and the period in which the detection region 4 is the 2 nd region A2 become the 1 st period, and the period in which the detection region 4 is the 3 rd region A3 becomes the 2 nd period.

Here, the temperature change amount used in the background correction unit 13 is a representative value of the change amount of the temperature values of the plurality of pixels with respect to the background data D2 during the period in which the detection region 4 is a region other than the specific region. The term "representative value" as used in the present disclosure includes an average value, a most frequent value, a central value, and the like, and in the present embodiment, the representative value is assumed to be an average value as an example. That is, as described above, the output data D1 and the background data D2 are each image data including a plurality of pixels each having a temperature value as a pixel value. Therefore, in the present embodiment, the background correction unit 13 uses, as the temperature change amount generated in the period (period 1), the average value of the change amounts of the temperature values of all the pixels constituting the background data D2 in the period (period 1) in which the detection region 4 is a region other than the specific region.

The background updating section 14 updates the background data D2. The background updating unit 14 updates the background data D2 corresponding to the detection area 4 at any time while the area is in the same area. That is, while the detection area 4 is stopped in any one of the plurality of areas A1 to A3, the background updating unit 14 updates the background data D2 corresponding to that area as needed. The details of the processing related to updating the background data D2 in the background updating unit 14 are described in the column "(2.3) operation".

In the present embodiment, the determination unit 11 determines whether or not the object 5 is present a plurality of times while the detection area 4 is in the same area, and the background update unit 14 updates the background data D2 every time the determination unit 11 determines whether or not the object is present. That is, the judgment unit 11 judges whether or not the object 5 is present and the background update unit 14 updates the background data D2 by the same number of times while the detection area 4 is in the same area.

The acquisition unit 15 is connected to the temperature sensor 2, and acquires output data D1 from the temperature sensor 2. In the present embodiment, the temperature sensor 2 outputs a thermal image as output data D1, and therefore the acquisition unit 15 acquires the output data D1 including the thermal image. Here, the frequency of acquiring the output data D1 by the acquisition unit 15 is defined by, for example, the frame rate of the temperature sensor 2. That is, if the frame rate of the temperature sensor 2 is 10 [ fps ] as an example, the acquisition section 15 acquires the output data D1 at 0.1 [ s ] intervals.

The background storage unit 16 includes, for example, a nonvolatile memory, and stores the background data D2. The background storage unit 16 stores the background data D2 in association with the 1 st area A1, the 2 nd area A2, and the 3 rd area A3, respectively. That is, in the present embodiment, the background data D2 is stored in the background storage unit 16 for each region (1 st region A1, 2 nd region A2, or 3 rd region A3) that is a candidate for the detection region 4.

When the background data D2 is corrected by the background correction unit 13, the background data D2 stored in the background storage unit 16 is rewritten into corrected background data D2. For example, when the background data D2 corresponding to the 1 st area A1 is corrected by the background correction unit 13, the background data D2 corresponding to the 1 st area A1 stored in the background storage unit 16 is rewritten to the corrected background data D2.

Similarly, when the background data D2 is updated by the background updating section 14, the background data D2 stored in the background storage section 16 is rewritten to the updated background data D2. For example, when the background data D2 corresponding to the 1 st area A1 is updated by the background updating unit 14, the background data D2 corresponding to the 1 st area A1 stored in the background storage unit 16 is rewritten to the updated background data D2.

Therefore, the latest background data D2, that is, the corrected or updated background data D2 is always stored in the background storage section 16.

Further, based on the output data D1 of the temperature sensor 2, that is, the thermal image acquired by the acquisition unit 15, it is possible to determine not only the presence or absence of the object 5, but also the temperature of, for example, the space, floor, wall, ceiling, and the like of the detection area 4. Accordingly, the object detection system 1 may output information on the temperature of the space, floor, wall, ceiling, and the like of the detection area 4 to the air conditioner 3 in addition to or instead of the presence or absence of the object 5. In this case, the air conditioner 3 can operate based on the temperature of the space, floor, wall, ceiling, and the like of the detection area 4.

(2.3) Action

Next, the operation of the object detection system 1 will be described with reference to fig. 2A to 4B. Here, a case will be described in which, in the sensor system 20 (including the object detection system 1) used in the air conditioning system 30, as shown in fig. 2A, a "person" existing in the living room 40 where the air conditioner 3 is installed is detected as the object 5.

The object detection system 1 determines whether or not the object 5 is present in the detection region 4 by the determination unit 11 based on the comparison result between the output data D1 of the temperature sensor 2 and the background data D2 acquired by the acquisition unit 15. Here, the object detection system 1 switches the detection area 4 between a plurality of areas (1 st area A1, 2 nd area A2, and 3 rd area A3) by the switching unit 12, and determines whether or not the object 5 is present in each of the plurality of areas A1 to A3 by the determination unit 11. That is, fig. 2A is a schematic plan view showing a state in which the detection region 4 is switched between the 1 st region A1, the 2 nd region A2 and the 3 rd region A3, and in particular, shows a state in which the detection region 4 is in the 1 st region A1. Here, as an example, the object detection system 1 sequentially switches the detection regions 4 in the order of the 1 st region A1, the 2 nd region A2, the 1 st region A1, the 3 rd region A3, the 2 nd region A2, and the 1 st region A1.

While the detection region 4 is fixed to any one of the plurality of regions A1 to A3, the object detection system 1 acquires a thermal image from the temperature sensor 2 as output data D1 by the acquisition unit 15, and compares the output data D1 with the background image D2. Fig. 2B shows a thermal image acquired by the acquisition unit 15 as the output data D1 when the detection area 4 is in the 1 st area A1, the 2 nd area A2, and the 3 rd area A3, respectively, in the example of fig. 2A. In fig. 2B, the output data D1 acquired in the 1 st area A1 is denoted as "center", the output data D1 acquired in the 2 nd area A2 is denoted as "right", and the output data D1 acquired in the 3 rd area A3 is denoted as "left". That is, as shown in fig. 2B, in the output data D1 when the detection area 4 is in the 1 st area A1, the temperature value (pixel value) of the pixel P1 corresponding to the object 5 (person) in the 1 st area A1 becomes large. In fig. 2B, pixels whose temperature values exceed a given value are indicated by hatched areas. Similarly, as shown in fig. 2B, in the output data D1 when the detection area 4 is in the 2 nd area A2, the temperature value (pixel value) of the pixel P1 corresponding to the object 5 (person) in the 2 nd area A2 becomes large.

In order to extract the pixel P1 corresponding to the object 5 (person) as described above, the object detection system 1 compares the output data D1 with the background data D2. The object detection system 1 basically uses the output data D1 of the temperature sensor 2 in the absence of the object 5 as the background data D2 as described above. Therefore, as shown in fig. 3A and 3B, the object detection system 1 acquires the output data D1 of the temperature sensor 2 in a state where the object 5 is not present as the background data D2 by the acquisition unit 15. Fig. 3A is a schematic plan view showing a state in which the detection region 4 is switched between the 1 st region A1, the 2 nd region A2 and the 3 rd region A3, and particularly shows a state in which the detection region 4 is in the 1 st region A1. Fig. 3B shows a thermal image acquired by the acquisition unit 15 as the background data D2 when the detection area 4 is in the 1 st area A1, the 2 nd area A2, and the 3 rd area A3, respectively, in the example of fig. 3A.

Then, the object detection system 1 calculates difference data by taking a difference between the output data D1 and the background data D2, and compares the calculated difference data with a threshold value, thereby determining whether or not the object 5 is present in the detection region 4. In the present embodiment, since the output data D1 and the background data D2 are both thermal images, the determination unit 11 generates differential data by taking a difference for each pixel. That is, the differential data includes image data having a differential value between the same pixels of the output data D1 and the background data D2 as a pixel value. The determination unit 11 determines that the object 5 is "present" based on the difference data exceeding the threshold value.

As an example, fig. 4B schematically shows a Y1 line section in the output data D1 shown in fig. 4A. That is, it is assumed that the temperature distribution as shown in fig. 4B is obtained by extracting 1 line of pixels P1 along the horizontal axis (X axis) of the output data D1 shown in fig. 4A. In this case, as shown in fig. 4B, the object detection system 1 calculates difference data by taking a difference between the output data D1 and the background data D2, and compares the calculated difference data with the threshold Vth1, thereby determining the presence or absence of the object 5 in the detection region 4. Here, the determination unit 11 determines that the object 5 is "present" based on the difference data exceeding the threshold Vth1. That is, in the example of fig. 4B, in a hatched area of data (indicated by a broken line) exceeding the background data D2 plus the threshold Vth1 among the output data D1, the differential data exceeds the threshold Vth1. The determination unit 11 determines that the object 5 is present, i.e., that "person" is present, in the hatched area.

Here, in order to distinguish between the object 5 and the heat source other than the object 5, the determination unit 11 may determine whether or not the object 5 (person) is present by using at least one of the size, shape, and pixel value (temperature value) of the pixel (hatched area) whose difference data exceeds the threshold Vth 1.

Fig. 5 to 7 are flowcharts showing an example of the operation of the object detection system 1 according to the present embodiment. In particular, in fig. 5 and 6, the processing is distinguished and indicated according to which of the plurality of areas A1 to A3 the detection area 4 is located. In fig. 5 and 6, the processing when the detection area 4 is the 1 st area A1 is shown in the "center" column, the processing when the detection area 4 is the 2 nd area A2 is shown in the "right" column, and the processing when the detection area 4 is the 3 rd area A3 is shown in the "left" column.

As shown in fig. 5, after the object detection system 1 is started, first, the background data D2 corresponding to the 3 rd area A3 is acquired (S1). Then, the object detection system 1 performs a switching process (S2) of switching the detection area 4 from the 3 rd area A3 to the 1 st area A1, and acquires the background data D2 corresponding to the 1 st area A1 (S3). Then, the object detection system 1 performs a switching process of switching the detection area 4 from the 1 st area A1 to the 2 nd area A2 (S4), and acquires the background data D2 corresponding to the 2 nd area A2 (S5). Thus, in the object detection system 1, acquisition of the background data D2 corresponding to the 1 st area A1, the 2 nd area A2, and the 3 rd area A3 is completed. The acquired background data D2 is stored in the background storage unit 16 in association with the 1 st area A1, the 2 nd area A2, and the 3 rd area A3, respectively.

Then, the object detection system 1 performs a switching process of switching the detection area 4 from the 2 nd area A2 to the 1 st area A1 (S6), and reads out the background data D2 corresponding to the 1 st area A1 from the background storage unit 16 (S7). After that, the object detection system 1 performs a judgment process described later with respect to the 1 st area A1 (S8). Then, the object detection system 1 calculates the amount of temperature change occurring while the detection area 4 is the 1 st area A1 by the background correction unit 13 (S9). At this time, the background correction unit 13 calculates an average value (representative value) of the amounts of change in the temperature values of the plurality of pixels with respect to the background data D2 in the period in which the detection area 4 is the 1 st area A1 as "temperature change amount".

Then, the object detection system 1 performs a switching process of switching the detection area 4 from the 1 st area A1 to the 2 nd area A2 (S10), and reads out the background data D2 corresponding to the 2 nd area A2 from the background storage unit 16 (S11). After that, the object detection system 1 executes a background correction process of correcting the background data D2 by the background correction unit 13 (S12). At this time, since the specific region is the 2 nd region A2, the background data D2 corresponding to the 2 nd region A2 is corrected based on the temperature change amount generated during the period in which the detection region 4 is a region other than the specific region (the 1 st region A1), that is, the temperature change amount obtained by the process S9. After that, the object detection system 1 performs a judgment process with respect to the 2 nd region A2 using the corrected background data D2 (S13). Then, the object detection system 1 calculates the amount of temperature change generated during the period when the detection area 4 is the 2 nd area A2 by the background correction section 13 (S14). At this time, the background correction unit 13 calculates an average value (representative value) of the amounts of change in the temperature values of the plurality of pixels with respect to the background data D2 in the period in which the detection area 4 is the 2 nd area A2, as "temperature change amount".

Then, the object detection system 1 performs a switching process (S15) of switching the detection area 4 from the 2 nd area A2 to the 1 st area A1, and reads out the background data D2 corresponding to the 1 st area A1 from the background storage unit 16 as shown in fig. 6 (S16). After that, the object detection system 1 executes a background correction process of correcting the background data D2 by the background correction unit 13 (S17). At this time, since the specific region is the 1 st region A1, the background data D2 corresponding to the 1 st region A1 is corrected based on the temperature change amount generated during the period in which the detection region 4 is a region other than the specific region (the 2 nd region A2), that is, the temperature change amount obtained by the process S14. After that, the object detection system 1 performs a judgment process with respect to the 1 st area A1 using the corrected background data D2 (S18). Then, the object detection system 1 calculates the amount of temperature change generated during the period when the detection area 4 is the 1 st area A1 by the background correction unit 13 (S19). At this time, the background correction unit 13 calculates an average value (representative value) of the amounts of change in the temperature values of the plurality of pixels with respect to the background data D2 in the period in which the detection area 4 is the 1 st area A1 as "temperature change amount".

Then, the object detection system 1 performs a switching process of switching the detection area 4 from the 1 st area A1 to the 3 rd area A3 (S20), and reads out the background data D2 corresponding to the 3 rd area A3 from the background storage unit 16 (S21). After that, the object detection system 1 executes a background correction process of correcting the background data D2 by the background correction unit 13 (S22). At this time, since the specific region is the 3 rd region A3, the background data D2 corresponding to the 3 rd region A3 is corrected based on the temperature change amount generated during the period in which the detection region 4 is a region other than the specific region (the 1 st region A1), that is, the temperature change amount obtained by the process S19. After that, the object detection system 1 performs a judgment process with respect to the 3 rd area A3 using the corrected background data D2 (S23).

Thereafter, by repeating the same process, the object detection system 1 switches the detection area 4 between the plurality of areas A1 to A3, and determines whether or not the object 5 is present in each of the plurality of areas A1 to A3.

Fig. 7 shows an outline of each judgment process (S8, S13, S18, S23). That is, in the judgment process, the object detection system 1 first acquires the latest thermal image from the temperature sensor 2 as the output data D1 (S101). Then, the object detection system 1 calculates differential data by taking the difference between the output data D1 and the background data D2 (S102). Then, the object detection system 1 compares the calculated difference data with a threshold value to determine whether or not the object 5 (person) is present in the detection area 4 (S103).

Then, the object detection system 1 performs updating of the background data D2 by the background updating section 14 (S104). At this time, the background updating unit 14 updates the background data D2 to the proximity output data D1. Specifically, the background updating section 14 generates differential data by taking a difference for each pixel with respect to the output data D1 and the background data D2, and adds update data obtained by multiplying the differential data by a given ratio (for example, several%) to the background data D2, thereby updating the background data D2. However, when it is determined that the object 5 is present in the processing S103, the area in which the object 5 is present is used for updating the background data D2 except for the output data D1. In other words, only the pixels of the region where the object 5 does not exist among the output data D1 are used for updating the background data D2. Thus, when the temperature of the living room 40 gradually changes, the background data D2 is updated to track the temperature change.

Then, the object detection system 1 determines whether or not a given time has elapsed from the start of the determination process (S105). At this time, if the given time has not elapsed (S105: NO), the process returns to the process S101, and if the given time has elapsed (S105: yes), the judgment process ends. Thus, the above-described processes S101 to S104 are repeated until a predetermined time elapses.

According to the operation of the object detection system 1 described above, the background correction unit 13 corrects the background data D2 corresponding to the specific region based on the temperature change amount during the period when the detection region 4 is a region other than the specific region. Therefore, even when the temperature of the living room 40 is raised by the air conditioner 3 during the period in which the detection area 4 is other than the specific area, the reliability (detection accuracy) of the detection of the object 5 in the object detection system 1 is not likely to be lowered.

That is, as shown in fig. 8, by correcting the background data D2 based on the temperature change amount Δt1, erroneous detection of the object 5 or missing detection of the object 5 is less likely to occur. Fig. 8 is a schematic view of a Y1 line section in the output data D1 shown in fig. 4A, similarly to fig. 4B. In summary, for example, when the specific region is the 1 st region A1, the background data D2 corresponding to the 1 st region A1 is corrected by the amount of the temperature change Δt1 generated during the period when the detection region 4 is a region other than the specific region (1 st region A1). In the example of fig. 8, the background data D2' before correction is indicated by a virtual line (two-dot chain line), and the background data D2 after correction is indicated by a solid line. Since the judgment processing is performed based on the corrected background data D2, erroneous detection of the object 5 or missing detection of the object 5 is less likely to occur.

Fig. 9 is a flowchart showing the operation of the object detection system according to the comparative example. The object detection system according to the comparative example described here assumes a configuration in which the background correction unit 13 is omitted from the object detection system 1 according to the present embodiment. That is, the object detection system according to the comparative example has the same configuration as the object detection system 1 according to the present embodiment except that the background correction unit 13 is not provided.

As shown in fig. 9, in the comparative example, the same operation as that of the object detection system 1 according to the present embodiment can be achieved except for the calculation process (S9, S14, S19 in fig. 5 and 6) and the background correction process (S12, S17, S22 in fig. 5 and 6) without the temperature change amount. That is, the process "Sc (α)" (α is 1 to 23) in fig. 9 corresponds to the process "S (α)" (α is 1 to 23) in fig. 5 and 6.

According to the object detection system according to the comparative example, since the detection area 4 is switched between the plurality of areas A1 to A3, the background data D2 corresponding to the specific area is not updated while the area other than the specific area is set as the detection area 4. Thus, for example, when the specific area is the 1 st area A1, the background data D2 corresponding to the specific area is not updated while the area other than the specific area (the 2 nd area A2) is set as the detection area 4. Therefore, for example, as shown in fig. 10A, as a result of a temperature rise occurring while the region other than the specific region (the 2 nd region A2) is set as the detection region 4, there is a possibility that the difference data between the output data D1 and the background data D2 exceeds the threshold value regardless of the presence or absence of the object 5. As a result, even if there is no object 5, it is determined that there is an object 5, and erroneous detection occurs.

In the object detection system according to the comparative example, the background data D2 may be acquired again instead of the process (Sc 11, sc16, sc 21) of reading out the background data D2. In this case, since the background data D2 is acquired again every time the detection area 4 is switched between the plurality of areas A1 to A3, there is a possibility that the object 5 (person) entering the specific area is not detected while the area other than the specific area is set as the detection area 4. That is, for example, as shown in fig. 10B, there is a possibility that the object 5 (person) that enters the specific area (1 st area A1) during the period in which the area other than the specific area (2 nd area A2) is set as the detection area 4 cannot be detected.

In contrast, in the object detection system 1 according to the present embodiment, the background correction unit 13 corrects the background data D2 corresponding to the specific region based on the amount of temperature change during the period in which the detection region 4 is a region other than the specific region, and thus erroneous detection and missing detection are less likely to occur. Therefore, the present embodiment has an advantage that although the detection region 4 is switched between the plurality of regions A1 to A3, the reliability (detection accuracy) of the detection of the object 5 in the object detection system 1 is not easily degraded.

(3) Modification examples

Embodiment 1 is but one of various embodiments of the present disclosure. As long as the object of the present disclosure can be achieved, embodiment 1 can be variously modified according to design or the like. The same functions as those of the object detection system 1 according to embodiment 1 may be embodied by an object detection method, a program, a nonvolatile recording medium storing the program, or the like. The object detection method according to one embodiment includes a switching process (see S2, S4, S6, S10, S15, S20 in fig. 5 and 6), a determination process (see S8, S13, S18, S23 in fig. 5 and 6), and a background correction process (see S12, S17, S22 in fig. 5 and 6). The switching process is a process of switching the detection area 4 between a plurality of areas A1 to A3 including at least a specific area. The determination process is a process of determining whether or not the object 5 is present in the detection region 4 based on the difference data between the output data D1 of the temperature sensor 2 and the background data D2. The temperature sensor 2 detects the temperature of the detection area 4. The background data D2 corresponds to the plurality of areas A1 to A3, respectively. The background correction processing is processing for correcting the background data D2 corresponding to the specific region based on the temperature change amount during the period when the detection region 4 is a region other than the specific region. Further, the program according to one aspect is a program for causing a computer system to execute the object detection method.

A modification of embodiment 1 is described below. The modified examples described below can be applied in appropriate combination.

In the object detection system 1, as shown in fig. 11A to 11C, the areas A1 to A3 that may become the detection areas 4 may be adjustable. Specifically, in fig. 11A, among 3 areas obtained by dividing the space in the living room 40 into 3 parts in a plan view, the central area is the 1 st area A1, the right area is the 2 nd area A2, and the left area is the 3 rd area A3 as viewed from the temperature sensor 2. On the other hand, as shown in fig. 11B, when the air conditioner 3 is installed in the corner of the left side of the living room 40 in a plan view, the 1 st area A1 in the center is adjusted to be inclined rightward with respect to the front surface of the air conditioner 3. As shown in fig. 11C, when the air conditioner 3 is installed in the right corner of the living room 40 in a plan view, the 1 st area A1 in the center is adjusted to be inclined to the left with respect to the front surface of the air conditioner 3. In this way, in the object detection system 1, the 1 st area A1 can be directed to the center of the living room 40 regardless of the position of the air conditioner 3, and a large part of the living room 40 can be used as the detection area 4.

In the modification examples of fig. 11A to 11C, the time for fixing the detection region 4 to the plurality of regions A1 to A3 is different depending on the regions A1 to A3. In summary, the switching section 12 performs switching of the detection area 4 at intervals of a given time, and therefore the detection area 4 is fixed to the respective areas A1 to A3 at intervals of a given time. Here, the given time is set individually for the 1 st area A1, the 2 nd area A2, and the 3 rd area A3, and thus the time for which the detection area 4 is fixed to the plurality of areas A1 to A3 is different for the areas A1 to A3. In particular, regarding the 1 st area A1 corresponding to the center of the living room 40, it is preferable that the given time be set longer than the 2 nd area A2 and the 3 rd area A3. Thus, the object detection system 1 can detect the presence or absence of the object 5 with emphasis on the 1 st area A1 in which the possibility of the presence of the object 5 (person) is high.

The object detection system 1 in the present disclosure includes a computer system in the processing section 10 or the like, for example. The computer system has a main configuration of a processor and a memory, which are hardware. The functions as the object detection system 1 in the present disclosure can be realized by the processor executing the program recorded in the memory of the computer system. The program may be recorded in advance in a memory of the computer system, may be provided via an electric communication line, or may be recorded in a nonvolatile recording medium such as a memory card, an optical disk, or a hard disk drive that can be read by the computer system. The processor of a computer system includes one or more electronic circuits including a semiconductor Integrated Circuit (IC) or a large scale integrated circuit (LSI). The term "integrated circuit" used herein, such as an IC or LSI, is defined as an integrated circuit, and includes an integrated circuit called a system LSI, VLSI (VERY LARGE SCALE Integration), or ULSI (Ultra LARGE SCALE Integration), depending on the degree of Integration. Further, an FPGA (Field-Programmable GATE ARRAY) programmed after the LSI is manufactured, or a logic device capable of realizing the reconfiguration of the bonding relationship inside the LSI or the reconfiguration of the circuit division inside the LSI can be used as a processor. The plurality of electronic circuits may be integrated in one chip or may be provided in a plurality of chips in a distributed manner. The plurality of chips may be integrated in one device or may be distributed among a plurality of devices.

In addition, the plurality of functions in the object detection system 1 are integrated in one housing and are not necessarily required for the object detection system 1, and the constituent elements of the object detection system 1 may be provided in a plurality of housings in a dispersed manner. Further, the function of at least a part of the object detection system 1, for example, the function of a part of the processing section 10 may be realized by cloud (cloud computing) or the like.

Further, the object detection system 1, the sensor system 20, and the air conditioning system 30 are not limited to residential facilities, but may be introduced into non-residential facilities such as offices, shops, hospitals, schools, nursing homes, and the like.

Further, the object detection system 1 and the sensor system 20 are not limited to the air conditioning system 30, and may be used for a lighting control system, a room entrance/exit management system, or the like, for example.

The driving unit 21 is not an essential component of the sensor system 20, and may be omitted as appropriate. When the driving unit 21 is omitted, the switching unit 12 may alternatively select and use the outputs of the plurality of temperature sensors 2 provided in correspondence with the plurality of areas A1 to A3, for example, to switch the detection area 4 between the plurality of areas A1 to A3.

The plurality of regions to be candidates for the detection region 4 are not limited to 3 regions A1 to A3, and may include 4 or more regions. Or the plurality of regions that become candidates for the detection region 4 may be two regions. When the detection area 4 is switched between the 1 st area A1 and the 2 nd area A2 only, for example, when the 1 st area A1 is the "specific area", the 2 nd area A2 is an area other than the "specific area". Similarly, when the 2 nd area A2 is the "specific area", the 1 st area A1 becomes an area other than the "specific area". In this case, when the 1 st area A1 is the "specific area", the period in which the detection area 4 is the 1 st area A1 becomes the 1 st period and the 3 rd period, and the period in which the detection area 4 is the 2 nd area A2 becomes the 2 nd period. Similarly, when the 2 nd area A2 is the "specific area", the period in which the detection area 4 is the 2 nd area A2 becomes the 1 st period and the 3 rd period, and the period in which the detection area 4 is the 1 st area A1 becomes the 2 nd period.

The background updating unit 14 is not necessarily configured to update the background data D2 every time the determining unit 11 determines the presence or absence of an object. That is, the number of times the determining section 11 determines whether or not the object 5 is present and the number of times the background updating section 14 updates the background data D2 may be different from each other while the detection region 4 is in the same region.

(Embodiment 2)

The object detection system 1 according to the present embodiment differs from the object detection system 1 according to embodiment 1 in the method of calculating the temperature change amount used by the background correction unit 13. Hereinafter, the same components as those of embodiment 1 are denoted by common reference numerals, and description thereof is omitted as appropriate.

In the 1 st configuration example of the present embodiment, as shown in fig. 12, the 1 st region A1 and the 2 nd region A2 or the 3 rd region A3 are repeated in the repetition region a 10. That is, in the 1 st area A1 and the 2 nd area A2, a part of each other is repeated in the repetition area a 10. Similarly, in the 1 st area A1 and the 3 rd area A3, a part of each other is repeated in the repetition area a 10.

In this case, the temperature change amount used by the background correction unit 13 is a representative value (for example, an average value) of the change amount of the temperature value of the pixel corresponding to the repetitive region a10 among the plurality of pixels related to the background data D2 in the period in which the detection region 4 is a region other than the specific region. That is, the temperature change amount is a representative value of the change amount of the temperature value of the pixel of the repetitive region a10 among the plurality of pixels of the background data D2 in the period in which the detection region 4 is a region other than the specific region and the region of the repetitive region a10 that overlaps the specific region. For example, if the specific area is the 2 nd area A2, the representative value of the amount of change in the temperature value of the pixel of the repetitive area a10 among the plurality of pixels concerning the background data D2 in the period in which the detection area 4 is the 1 st area A1 is utilized as the temperature change amount. Further, if the specific area is the 3 rd area A3, the representative value of the amount of change in the temperature value of the pixel of the repetitive area a10 among the plurality of pixels concerning the background data D2 in the period in which the detection area 4 is the 1 st area A1 is utilized as the temperature change amount.

According to the configuration example 1 described above, since the temperature change generated in the repetitive region a10 that is a part of the specific region is reflected in the correction of the background data D2 corresponding to the specific region, the accuracy of the correction of the background data D2 is improved.

In the configuration example 2 according to the present embodiment, the temperature change amount used by the background correction unit 13 is a value reflecting the distribution of the temperature values in the background data D2 during the period in which the detection region 4 is a region other than the specific region. That is, when the background data D2 changes with a specific distribution during the period in which the detection region 4 is a region other than the specific region, the distribution is reflected in the temperature change amount.

As an example, assume a case where a temperature rise in the living room 40 occurs while the detection area 4 is the 1 st area A1, and the temperature rise in the 2 nd area A2 is larger than that in the 3 rd area A3. In this case, if the specific region is assumed to be the 2 nd region A2 or the 3 rd region A3, the background data D2 changes as shown in fig. 13A while the detection region 4 is a region other than the specific region (the 1 st region A1). In fig. 13A, the background data D2 before the change in the period in which the detection region 4 is the 1 st region A1 is indicated by a virtual line (two-dot chain line), and the background data D2 after the change is indicated by a solid line. As is clear from the distribution of the temperature values in the background data D2 during the period in which the detection region 4 is a region other than the specific region, the temperature rise in the region on the right side of the 1 st region A1 (the 2 nd region A2) is larger than that in the region on the left side of the 1 st region A1 (the 3 rd region A3). Accordingly, the background correction unit 13 uses the temperature change amount Δt1 for correction of the background data D2 corresponding to the 2 nd area A2, and uses the temperature change amount Δt2 (< Δt1) for correction of the background data D2 corresponding to the 3 rd area A3.

According to the above configuration example 2, since the temperature distribution of the region other than the specific region is reflected in the correction of the background data D2 corresponding to the specific region, the accuracy of the correction of the background data D2 is improved.

In the 3 rd configuration example according to the present embodiment, the temperature change amount used by the background correction unit 13 is a representative value of the change amount of the temperature value of the pixel other than the specific pixel among the plurality of pixels of the background data D2 in the period in which the detection region 4 is the region other than the specific region. That is, not the change in the temperature value of all the pixels of the background data D2 in the period in which the detection region 4 is a region other than the specific region but the change in the temperature value other than a part of the pixels (specific pixels) is reflected in the temperature change amount.

As an example, assume a case where, for example, the television receiver 401 (see fig. 2A) is started up while the detection area 4 is the 1 st area A1, and the television receiver 401 becomes a fixed heat source, thereby locally generating a temperature rise in the living room 40. In this case, if the specific region is assumed to be the 2 nd region A2 or the 3 rd region A3, the background data D2 changes as shown in fig. 13B while the detection region 4 is a region other than the specific region (the 1 st region A1). In fig. 13B, the background data D2 before the change in the period in which the detection region 4 is the 1 st region A1 is indicated by a virtual line (two-dot chain line), and the background data D2 after the change is indicated by a solid line. In the background data D2 during the period in which the detection region 4 is a region other than the specific region, it is known that a local temperature rise occurs due to the influence of the fixed heat source. Accordingly, the background correction unit 13 uses the temperature change amount Δt1 for correction of the background data D2 corresponding to the 2 nd region A2 as a representative value (for example, an average value) of the change amounts of the temperature values of the pixels other than the specific pixel (the pixel in the range shown by Z1 in fig. 13B). Here, as an example, it is determined that a local temperature change has occurred in a part of the pixels, that is, that a part of the pixels are specific pixels, based on a difference in temperature value of a predetermined value or more occurring between a part of the pixels and the remaining pixels among the plurality of pixels constituting the background data D2.

According to the above configuration example 3, since the influence of the fixed heat source in the specific region is not reflected in the correction of the background data D2 corresponding to the specific region, the accuracy of the correction of the background data D2 is improved.

The configuration described in embodiment 2 can be appropriately combined with the various configurations described in embodiment 1 (including modifications).

(Summary)

As described above, the object detection system (1) according to the 1 st aspect includes the switching unit (12), the determination unit (11), and the background correction unit (13). A switching unit (12) switches the detection area (4) between a plurality of areas (A1-A3) including at least a specific area. A judging unit (11) judges whether or not an object (5) is present in the detection region (4) based on the result of comparing the output data (D1) of the temperature sensor (2) for detecting the temperature of the detection region (4) with the background data (D2) corresponding to each of the plurality of regions (A1-A3). A background correction unit (13) corrects the background data (D2) corresponding to the specific region based on the temperature change amount (delta T1) during the period when the detection region (4) is a region other than the specific region.

According to this aspect, the detection region (4) in which the temperature is detected by the temperature sensor (2) is switched by the switching unit (12) between the plurality of regions (A1 to A3), and therefore the region of the detectable object (5) can be enlarged as compared with the case in which the detection region (4) is fixed. That is, in the object detection system (1), the area of the detectable object (5) is not limited to the angle of view of the temperature sensor (2), and the object (5) existing outside the angle of view of the temperature sensor (2) can be detected. In the object detection system (i), the background correction unit (13) corrects the background data (D2) corresponding to the specific region based on the temperature change amount (DeltaT 1) during the period when the detection region (4) is a region other than the specific region. Thus, although the detection area (4) is switched between the plurality of areas (A1-A3), the reliability of the detection of the object (5) in the object detection system (1) is not easily lowered.

In the object detection system (1) according to claim 2, in claim 1, the output data (D1) and the background data (D2) are each image data including a plurality of pixels CP1 each having a temperature value as a pixel value.

According to this aspect, the presence or absence of the object (5) is determined based on the image data, and thus the reliability of detection of the object (5) is improved.

In the object detection system (1) according to claim 3, in claim 2, the temperature change amount (Δt1) is a representative value of the change amount of the temperature values of the plurality of pixels (P1) with respect to the background data (D2) during the period in which the detection region (4) is a region other than the specific region.

According to this aspect, the accuracy of correction of the background data (D2) corresponding to the specific region can be improved.

In the object detection system (1) according to claim 4, in claim 2, the temperature change amount (Δt1) is a representative value of a change amount of a temperature value of a pixel of the repetitive region (a 10) among a plurality of pixels (P1) of the background data (D2) in a period in which the detection region (4) is a region other than the specific region and the repetitive region (a 10) overlaps the specific region, and the repetitive region (a 10) is a part of the specific region.

In the object detection system (1) according to claim 5, in claim 2, the temperature change amount (Δt1) is a value reflecting a distribution of temperature values in the background data (D2) during a period in which the detection region (4) is a region other than the specific region.

In the object detection system (1) according to claim 6, in claim 2, the temperature change amount (Δt1) is a representative value of the change amount of the temperature value of the pixel other than the specific pixel among the plurality of pixels (P1) of the background data (D2) in the period in which the detection region (4) is a region other than the specific region.

In the object detection system (1) according to claim 7, in any one of the embodiments 1 to 6, the determination unit (11) determines whether or not the object (5) is present a plurality of times while the detection area (4) is in the same area.

According to this aspect, the detection accuracy of the object (5) can be improved.

The object detection system (1) according to claim 8 further includes, in claim 7: a background updating unit (14) updates the background data (D2) every time the judging unit (11) judges the presence or absence of the object (5).

In the object detection system (1) according to claim 9, in any one of the modes 1 to 8, the object (5) is a moving object.

According to this aspect, the movement of the object (5) as a moving object can be detected.

In the object detection system (1) according to claim 10, in any one of claims 1 to 9, the time for which the detection region (4) is fixed to each of the plurality of regions (A1 to A3) differs from region to region.

According to this aspect, the object (5) can be detected with emphasis on any one of the plurality of areas (A1 to A3).

In the object detection system (1) according to claim 11, in any one of claims 1 to 10, the plurality of areas (A1 to A3) includes 3 or more areas.

According to this aspect, the area of the detectable object (5) can be further enlarged.

The sensor system (20) according to claim 12 includes the object detection system (1) according to any one of claims 1 to 11 and the temperature sensor (2).

According to this aspect, the detection region (4) in which the temperature is detected by the temperature sensor (2) is switched by the switching unit (12) between the plurality of regions (A1 to A3), and therefore the region of the detectable object (5) can be enlarged as compared with the case in which the detection region (4) is fixed. That is, in the sensor system (20), the area in which the object (5) can be detected is not limited to the angle of view of the temperature sensor (2), and the object (5) existing outside the angle of view of the temperature sensor (2) can be detected.

An air conditioning system (30) according to claim 13 comprises: a sensor system (20) according to claim 12, and an air conditioner (3) that operates based on an output of the determination unit (11).

According to this aspect, the detection region (4) in which the temperature is detected by the temperature sensor (2) is switched by the switching unit (12) between the plurality of regions (A1 to A3), and therefore the region of the detectable object (5) can be enlarged as compared with the case in which the detection region (4) is fixed. That is, in the air conditioning system (30), the area of the detectable object (5) is not limited to the angle of view of the temperature sensor (2), and the object (5) existing outside the angle of view of the temperature sensor (2) can be detected.

The object detection method according to the 14 th aspect includes a switching process, a judgment process, and a background correction process. The switching process is a process of switching the detection area (4) between a plurality of areas (A1-A3) including at least a specific area. The determination process is a process of determining whether or not the object (5) is present in the detection region (4) based on a result of comparing the output data (D1) of the temperature sensor (2) for detecting the temperature of the detection region (4) with the background data (D2) corresponding to each of the plurality of regions (A1 to A3). The background correction process is a process of correcting the background data (D2) corresponding to the specific region based on the temperature change amount (DeltaT 1) during the period when the detection region (4) is a region other than the specific region.

According to this aspect, the detection region (4) in which the temperature is detected by the temperature sensor (2) is switched between the plurality of regions (A1 to A3) by the switching process, and therefore the region of the detectable object (5) can be enlarged as compared with the case in which the detection region (4) is fixed. That is, in the object detection method, the area of the detectable object (5) is not limited to the angle of view of the temperature sensor (2), and the object (5) existing outside the angle of view of the temperature sensor (2) can be detected.

The program according to claim 15 is a program for causing a computer system to execute the object detection method according to claim 14.

According to this aspect, the detection region (4) in which the temperature is detected by the temperature sensor (2) is switched between the plurality of regions (A1 to A3) by the switching process, and therefore the region of the detectable object (5) can be enlarged as compared with the case in which the detection region (4) is fixed. That is, in the above-described program, the region of the detectable object (5) is not limited to the angle of view of the temperature sensor (2), and the object (5) existing outside the angle of view of the temperature sensor (2) can be detected.

The present invention is not limited to the above-described embodiments, and various configurations (including modifications) of the object detection system (1) according to embodiment 1 and embodiment 2 can be embodied by an object detection method and a program.

The configurations according to aspects 2 to 11 are not necessary for the object detection system (1), and can be omitted appropriately.

Symbol description

1 An object detection system;

2, a temperature sensor;

3 an air conditioner;

4, detecting a region;

5 objects;

A judgment unit 11;

12 switching part;

13 a background correction unit;

14 a background updating part;

a 20 sensor system;

30 an air conditioning system;

a1 to A3 regions;

d1, outputting data;

D2 background data;

Delta T1 temperature variation.

Claims

1. A sensor system includes an object detection system and a temperature sensor,

The temperature sensor is configured to be rotatable,

The object detection system is provided with:

a switching unit configured to rotate the temperature sensor and switch a detection area between a plurality of areas including at least a specific area;

A determination unit configured to determine whether or not an object is present in the detection area based on a result of comparing output data of the temperature sensor for detecting a temperature of the detection area with background data corresponding to each of the plurality of areas; and

And a background correction unit configured to correct the background data corresponding to the specific region during the period in which the detection region is the specific region, based on a temperature change amount of the background data corresponding to the specific region during the period in which the detection region is a region other than the specific region.

2. The sensor system of claim 1, wherein,

The output data and the background data are each image data including a plurality of pixels each having a temperature value as a pixel value.

3. The sensor system of claim 2, wherein,

The temperature change amount is a representative value of a change amount of the temperature values of the plurality of pixels with respect to the background data during a period in which the detection region is a region other than the specific region.

4. The sensor system of claim 2, wherein,

The temperature change amount is a representative value of a change amount of the temperature value of a pixel of the repetitive region among the plurality of pixels of the background data in a period in which the detection region is a region other than the specific region and is a region that is repetitive with the specific region, the repetitive region being a part of the specific region.

5. The sensor system of claim 2, wherein,

The temperature change amount is a value reflecting a distribution of the temperature value in the background data during a period in which the detection region is a region other than the specific region.

6. The sensor system of claim 2, wherein,

The temperature change amount is a representative value of a change amount of the temperature value of a pixel other than a specific pixel among the plurality of pixels with respect to the background data in a period in which the detection region is a region other than the specific region.

7. The sensor system according to any one of claims 1 to 6, wherein,

The determination unit determines whether or not the object is present a plurality of times while the detection area is in the same area.

8. The sensor system of claim 7, wherein,

The device further comprises: and a background updating unit configured to update the background data each time the judging unit judges whether or not the object is present.

9. The sensor system according to any one of claims 1 to 6, wherein,

The object is a moving object.

10. The sensor system according to any one of claims 1 to 6, wherein,

The time at which the detection regions are fixed to the plurality of regions, respectively, differs from region to region.

11. The sensor system according to any one of claims 1 to 6, wherein,

The plurality of regions includes 3 or more regions.

12. An air conditioning system is provided with:

The sensor system of any one of claims 1-11; and

The air conditioner operates based on the output of the judging unit.

13. An object detection method, comprising:

A switching process of rotating the temperature sensor and switching the detection area between a plurality of areas including at least the specific area;

A determination process of determining whether or not an object is present in the detection area based on a result of comparing output data of the temperature sensor for detecting a temperature of the detection area with background data corresponding to each of the plurality of areas; and

And a background correction process of correcting the background data corresponding to the specific region during the period in which the detection region is the specific region, based on a temperature change amount of the background data corresponding to the specific region during the period in which the detection region is the region other than the specific region.

14. A nonvolatile recording medium having recorded thereon a program for causing a computer system to execute the object detection method according to claim 13.