JP7347241B2 - stair safety device - Google Patents

Description

The present invention relates to a device for ensuring the safety of people going up and down stairs.

Patent Document 1 discloses a speed sensor that measures the moving speed of a person going up and down stairs, a plurality of impact sensors installed at each step of the stairs, and a system that determines whether a person has fallen based on the outputs of the speed sensor and the impact sensor. A stairway safety device is disclosed that includes a control device for controlling a stairway, and a plurality of airbags arranged at each step. The control device operates an airbag placed in a lower stage than the stage where the impact was detected.

Japanese Patent Application Publication No. 2000-248704

The stair safety device described in Patent Document 1 detects a fall of a person when the person falls and collides with the stairs. Additionally, the location of the person is determined by the impact sensor detecting the impact. That is, the stair safety device described in Patent Document 1 cannot prevent a person from colliding with the stairs for the first time.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to provide a technique that can prevent people from colliding with stairs.

(1) The stair safety device according to the present invention includes a detection device that uses a space through which a person ascending or descending stairs passes as a detection area, and outputs detection information that can identify the posture or change in posture and position of the person; A plurality of airbag devices arranged on the side of the stairs and lined up along the direction in which the plurality of treads of the stairs are lined up, and a drive signal into which the above-mentioned detection information is input and which individually activates each of the above-mentioned airbag devices. and a controller capable of outputting. The controller performs a judgment process to determine whether or not a person going up and down the stairs will fall, based on the input detection information, and determines the height of the person indicated by the detection information based on the judgment that the person will fall. An operation process of outputting a drive signal to the airbag device located below the position is executed.

The stair safety device according to the present invention determines whether or not a person will fall based on the person's posture and activates the airbag device located below the person who is falling. This can prevent injuries caused by collision with the floor, etc.

(2) The airbag device includes a drive device and an airbag inflated by the drive device, and the plurality of airbags are provided so as to overlap vertically in an inflated state, In the actuation process, the controller may simultaneously output a drive signal to all the airbag devices located below the height position indicated by the detection information.

Since all airbag devices located below the height of the person who falls are activated at the same time, multiple activated airbags overlap one above the other, making it possible to more reliably prevent injuries to people due to falls. .

(3) The detection device may be a plurality of sensors that respectively irradiate sound waves or laser light and receive or receive sound waves or laser light reflected by the person. The stair safety device according to the present invention further includes a wall material that holds the plurality of sensors arranged apart from each other and the airbag device arranged between the sensors in the vertical direction.

The use of a wall material provided with a plurality of sensors and airbag devices facilitates the installation of the stair safety device in a building.

(4) The airbag device includes a drive device and an airbag inflated by the drive device, and the inflated airbag may have a mat shape that spreads in a horizontal direction.

An airbag that expands horizontally into a mat shape can catch a person falling more reliably than a spherical airbag.

(5) The above-mentioned detection device is a plurality of laser sensors arranged above or to the side of the stairs, and each of the above-mentioned laser sensors irradiates a laser beam to each of a plurality of individual detection areas that are divided into the above-mentioned detection areas. The sensor receives the reflected light of the irradiated laser beam and outputs individual detection information and identification information according to the received reflected light, and the above-mentioned judgment process is based on the above-mentioned individual detection information and the above-mentioned identification information. The process may include identifying the identification information of the laser sensor that has detected the person, and determining whether or not the person will fall based on the identified identification information.

By using a plurality of laser sensors, it is possible to determine whether a person has fallen down the stairs, and it is also possible to specify the position of the falling person.

(6) The above-mentioned detection device is a human detection sensor capable of individually detecting infrared rays incident from each of a plurality of individual detection areas divided into the above-mentioned detection area, or a human sensor capable of detecting changes in infrared rays incident from the above-mentioned individual detection areas. The sensor is a sensor that outputs the detection information including individual detection information and individual identification information for each of the individual detection areas, and the judgment process is performed based on the individual detection information and the individual identification information. It may be a process of determining whether or not.

By using a human sensor, it is possible to determine whether or not a person has fallen down the stairs, and it is also possible to specify the position of the person who has fallen.

(7) The detection device is a three-dimensional laser sensor that irradiates the detection area with scanning light, receives reflected light of the scanning light, and outputs image data generated based on the received reflected light as the detection information. The controller has a memory that stores judgment image data indicating a falling posture, and the judgment process includes an image of a person indicated by the inputted image data and a falling posture indicated by the judgment image data. It may be a process of determining whether or not the person will fall based on points that match or differ from the image of the person.

By using a three-dimensional laser sensor, it is possible to determine whether a person has fallen down the stairs, and it is also possible to specify the position of the falling person.

(8) The detection device is a camera that images the stairs and the space above the stairs and outputs image data, and the controller has a memory that stores judgment image data indicating a falling posture; The judgment process is a process of judging whether or not the person will fall based on the points of agreement or difference between the image of the person shown by the inputted image data and the image of the person in the falling posture shown by the judgment image data. , the controller may further execute a position specifying process for specifying the height position of the person who is determined to be falling, based on the image shown by the image data.

By using a camera, it is possible to determine whether or not a person has fallen down the stairs, and it is also possible to specify the position of the person who has fallen.

The stair safety device according to the present invention can prevent people from colliding with stairs and being injured.

FIG. 1 is a functional block diagram of the stair safety device 10. As shown in FIG. FIG. 2(A) is a schematic side view of a straight staircase 50, and FIG. 2(B) is a schematic plan view of the staircase 50 which is a turn-back staircase. FIG. 3 is an explanatory diagram illustrating a state in which the airbag 21 is inflated. FIG. 4 is a flowchart showing the processing executed by the control program 18. FIG. 5(A) is a diagram showing the laser sensor 40 that has detected a person among the plurality of laser sensors 40 belonging to the second sensor group 32, and FIGS. 31 is a diagram showing a laser sensor 40 that has detected a person among a plurality of laser sensors 40 belonging to No. 31. FIG. FIG. 6 is a flowchart showing the processing executed by the control program 18 in the first modification. 7A and 7B are diagrams according to Modification Example 3, in which (A) is a schematic side view of a straight staircase 50, and (B) is a schematic plan view of the staircase 50 that is a turn-back staircase. FIG. 8 is a flowchart showing the processing executed by the control program 18 in the third modification. FIG. 9(A) is a diagram according to Modification Example 4, which is a schematic plan view of the stairs 50, and FIG. 9(B) is a diagram according to Modification Example 7, in which the airbag 21 is inflated. It is a figure showing a state. FIG. 10 is a flowchart showing the processing executed by the control program 18 in the fourth modification.

Embodiments of the present invention will be described below. Note that the embodiments described below are merely examples of the present invention, and it goes without saying that the embodiments of the present invention can be modified as appropriate without changing the gist of the present invention.

In this embodiment, a stair safety device 10 (FIG. 1) that is installed on a staircase 50 (FIG. 2) of a building (not shown) having two or more floors and detects a fall of a person going up and down the stairs 50 will be described. . In response to detecting a fall of a person, the stair safety device 10 activates an airbag device 20 (FIG. 1) and sends an email indicating that a person has fallen. This will be explained in detail below.

As shown in FIG. 1, the stair safety device 10 includes a terminal device 11, a first sensor group 31, a second sensor group 32, a third sensor group 33 connected to the terminal device 11, and a plurality of airbag devices. 20, and a wall material 51 that holds a first sensor group 31, a second sensor group 32, a third sensor group 33, and a plurality of airbag devices 20. Note that in FIG. 1, only one airbag device 20 is shown. Furthermore, the cameras 62 and 63, the three-dimensional laser sensors 64 and 65, the first sensor group 71, the second sensor group 72, and the third sensor group 73 indicated by broken lines in FIG. explain. Below, when the first sensor group 31, the second sensor group 32, and the third sensor group 33 are not distinguished, they will be described as sensor groups 31, 32, and 33.

The terminal device 11 is, for example, a personal computer or a management device attached to a wall inside a building to manage the building. The terminal device 11 includes a controller 12 , a communication interface 13 , and a power supply circuit 14 . In addition, in FIG. 1, the communication interface 13 is abbreviated as communication I/F13.

The communication interface 13 is an interface that performs communication according to the Internet protocol, and is connected to the Internet 19 via a router (not shown).

The power supply circuit 14 is connected to a commercial AC power source (not shown) such as 100V, 110V, 120V, 200V, 220V, or 240V via a power cable or the like. The power supply circuit 14 is an AC-DC converter that converts alternating current voltage to direct current voltage. The power supply circuit 14 supplies driving power to the controller 12, the communication interface 13, the sensor groups 31, 32, 33, and the airbag device 20. Note that illustration of power supply lines connecting the power supply circuit 14, the communication interface 13, the sensor groups 31, 32, 33, and the airbag device 20 is omitted. Further, a switching element is provided on the feed line. This switching element is turned on and off by inputting a drive signal from the controller 12. That is, the supply of driving power to the sensor groups 31, 32, and 33 is controlled by the controller 12.

The controller 12 includes a CPU 15 that is a central processing unit, a memory 16, and a communication bus 17.

The memory 16 is, for example, a ROM, a RAM, an EEPROM, a portable storage medium such as a USB memory attached to a mounting section (not shown), or a buffer. The memory 16 stores the control program 18, threshold values A and B, and email addresses. Note that the judgment image data shown in FIG. 1 will be explained in a modified example.

The control program 18 is a program executed by the CPU 15, and is a program that executes a process of detecting a fall of a person. The processing executed by the control program 18 will be described in detail later.

The threshold values A and B are used when the control program 18 determines whether or not a fall has occurred. The details will be described later. The e-mail address indicates the address of an e-mail sent when the control program 18 detects a fall of a person. The e-mail address is, for example, an e-mail address registered by a family member who uses the building or a relative of the family member.

The communication bus 17 is connected to the CPU 15 , memory 16 , communication interface 13 , sensor group 31 , 32 , 33 , and airbag device 20 . That is, the control program 18 executed by the CPU 15 can read information and data from the memory 16 through the communication bus 17 and store the information and data in the memory 16, and can send and receive mail, information, and data through the communication interface 13. Detection information detected by the sensor groups 31, 32, and 33 can be acquired, and a drive signal can be output to the airbag device 20 to operate the airbag device 20.

The sensor groups 31, 32, and 33 each include a plurality of laser sensors 40. The number of laser sensors 40 that each of the sensor groups 31, 32, and 33 has is determined by the type and floor plan of the stairs 50. The types of stairs 50 include, for example, straight stairs, spiral stairs, and folded stairs. In the example shown in FIG. 2(A), the stairs 50 are linear stairs, and in the example shown in FIG. 2(B), the stairs 50 are folded stairs. The laser sensors 40 may all or partially have the same specifications, or may have all different specifications. An example in which all laser sensors 40 have the same specifications will be described below.

The laser sensor 40 includes an irradiating section that irradiates laser light, and a light receiving section that receives reflected light reflected by an object such as a person and converts the received reflected light into a voltage. The light receiving section is, for example, a photodiode. The laser sensor 40 outputs detection information including, for example, identification information, information indicating the difference between the timing of irradiating the laser beam and the timing of receiving the reflected light, and information corresponding to the voltage value output by the light receiving section. Output.

The identification information is information that individually identifies the plurality of laser sensors 40. Information indicating the difference between the timing at which the laser beam was irradiated and the timing at which the reflected light was received is determined by whether the laser beam was reflected by a wall adjacent to the stairs 50 or the treads 52 of the stairs 50, or by a person going up or down the stairs 50. Indicates whether the laser beam is reflected by an object. Information corresponding to the voltage value output by the light receiving section indicates whether the laser beam is reflected by a wall or the step board 52, or by an object such as a person going up and down the stairs 50. That is, the controller 12 can determine whether the laser sensor 40 has detected a person based on the detection information output by the laser sensor 40. In other words, the controller 12 can individually identify the laser sensor 40 that has detected a person from among the plurality of laser sensors 40 based on the detection information input from the plurality of laser sensors 40.

Note that the detection information output by the laser sensor 40 may be any information that allows the controller 12 to determine whether or not a person has been detected, and may be detection information other than the above-mentioned example. Further, a relay device may be provided between the plurality of laser sensors 40 and the terminal device 11. The relay device determines whether or not each laser sensor 40 has detected a person based on the detection information input from each laser sensor 40, and transmits information indicating whether or not each laser sensor 40 has detected a person to the terminal. It may also be input into the device 11.

An example in which the stairs 50 are linear stairs as shown in FIG. 2(A) will be described below.

The laser sensor 40 of the first sensor group 31 is a sensor for detecting whether a person going up and down the stairs 50 is in a falling position. The laser sensor 40 of the first sensor group 31 is provided on a wall material 51 of one of a pair of opposing walls provided adjacent to the stairs 50. To explain in detail, the plurality of laser sensors 40 are provided in line in the vertical direction and the horizontal direction, and are arranged in a so-called matrix shape or lattice shape. Note that in FIG. 2(A), the laser sensor 40 belonging to the first sensor group 31 is indicated by a circle filled in gray.

The laser sensors 40 of the first sensor group 31 are provided across the stairs 50 from the entrance 53 to the exit 54 . That is, the plurality of laser sensors 40 of the first sensor group 31 use the entire space above the stairs 50 as a detection area.

Among the plurality of laser sensors 40 belonging to the first sensor group 31 and belonging to a row arranged in the vertical direction, the laser sensor 40 located at the lowest position is at the same height position as the tread 52 of the stairs 50 or from the tread 52 It is also located slightly (several centimeters) above. Among the plurality of laser sensors 40 belonging to the rows arranged in the vertical direction, the laser sensor 40 located at the top is located at a position above the top of the head of the person standing on the footboard 52. That is, the plurality of laser sensors 40 belonging to the first sensor group 31 have a detection area that includes the area from the head to the feet of a person going up and down the stairs 50.

The laser sensor 40 of the first sensor group 31 is installed in such a direction that it irradiates the wall surface of the wall material 51 with laser light substantially perpendicularly. That is, the plurality of laser sensors 40 of the first sensor group 31 define the space above the stairs 50 through which a person going up and down the stairs 50 passes as a detection area (hereinafter also referred to as a first detection area). do. The first detection area is a space (area) where the plurality of laser sensors 40 belonging to the first sensor group 31 irradiate laser light, and is a space (area) where the laser sensors 40 can detect a person. In other words, the detection area is a space (area) that is irradiated with a detection wave such as a laser beam, and is a space (area) where an object such as a person can be detected. Each space to which each laser sensor 40 of the first sensor group 31 irradiates laser light is an example of an individual detection area. The individual detection area is a space that is long in the width direction of the stairs 50 (the direction perpendicular to the plane of FIG. 2A). That is, the first detection area, which is the space where people go up and down on the stairs 50, is divided into a plurality of individual detection areas that are long in the width direction of the stairs 50, and each individual detection area is divided so that each individual detection area is irradiated with a laser beam. Laser sensors 40 are arranged respectively.

The distance H between two adjacent laser sensors 40 in the vertical direction is, for example, the same dimension as the riser of the stairs 50, and is from several cm to several tens of cm, preferably from 10 cm to 20 cm. The distance D between two adjacent laser sensors 40 arranged in the horizontal direction is, for example, the same as the tread (depth of one step) of the stairs 50, or half the tread, and ranges from several cm to several tens of cm. , preferably from several cm to 20 cm.

The separation distance D between two adjacent laser sensors 40 arranged in the horizontal direction is shorter than the separation distance H between the two laser sensors 40 arranged next to each other in the vertical direction. That is, the resolution in the horizontal direction is higher than the resolution in the vertical direction. The reason why the resolution in the horizontal direction is higher than the resolution in the vertical direction is to accurately detect that a person going up and down the stairs 50 is in a falling posture. The falling posture is, for example, a forward leaning posture and a posture that is elongated in the horizontal direction. By increasing the resolution in the horizontal direction, it is possible to accurately detect whether or not the user is in a falling position. Details will be described later.

The laser sensor 40 of the second sensor group 32 is a sensor for detecting the height and walking posture of a person entering the stairs 50. The laser sensor 40 of the second sensor group 32 is provided in a part of the wall material 51 adjacent to the entrance 53 and exit 54 of the stairs 50.

Like the laser sensors 40 of the first sensor group 31, the laser sensors 40 of the second sensor group 32 are arranged in the vertical and horizontal directions so as to be able to detect the height and walking posture of a person entering the stairs 50. , arranged in a matrix or grid.

The laser sensor 40 of the second sensor group 32 is attached to the wall material 51 in such a direction that it irradiates a laser beam substantially perpendicularly to the wall surface of the wall material 51. That is, the plurality of laser sensors 40 of the second sensor group 32 detect the space above the corridor and floor of the entrance 53 and exit 54 of the stairs 50, in which a person entering the stairs 50 walks. (hereinafter also referred to as the second detection area). The second detection area is a space (area) where each laser sensor 40 of the second sensor group 32 irradiates laser light, and is a space (area) where the laser sensor 40 can detect a person. In other words, the second detection area is a space (area) that is irradiated with a detection wave such as a laser beam, and is a space (area) where an object such as a person can be detected.

The number of laser sensors 40 arranged in the horizontal direction, that is, the length of the area in which the second sensor group 32 can detect a person in the left-right direction in FIG. The laser beam is set to be able to be irradiated on both at the same time. In addition, the number of laser sensors 40 arranged in the vertical direction, that is, the length of the area in which the second sensor group 32 can detect a person in the vertical direction, is such that the laser beam can be irradiated simultaneously to the top of the head and feet of a person who is standing upright. It is set. Note that in FIG. 2(A), the laser sensor 40 belonging to the second sensor group 32 is indicated by an outlined circle.

In the second sensor group 32, the distance between two adjacent laser sensors 40 arranged in the vertical and horizontal directions is set to a distance that allows the height and walking posture of a person walking at the entrance 53 or exit 54 to be detected. has been done. Specifically, in the second sensor group 32, the separation distance between the two vertically adjacent laser sensors 40 may be the same as the above-mentioned separation distance H, or may be different from the separation distance H. Good too. Further, in the second sensor group 32, the separation distance between two adjacent laser sensors 40 arranged in the horizontal direction may be the same as or different from the above-mentioned separation distance D.

The laser sensor 40 of the third sensor group 33 is a sensor for detecting that a person has entered the entrance 53 and exit 54 of the stairs 50. The laser sensor 40 of the third sensor group 33 is provided on the opposite side of the first sensor group 31 with the second sensor group 32 in between. The plurality of laser sensors 40 of the third sensor group 33 are arranged in a line in the vertical direction. Further, the laser sensor 40 of the third sensor group 33 is attached to the wall material 51 in such a direction that it irradiates a laser beam substantially perpendicularly to the wall surface of the wall material 51. Note that the laser sensor 40 of the third sensor group 33 may be used together with the laser sensor 40 of the second sensor group 32 to detect the height and walking posture of a person walking at the entrance 53 and entrance 54 of the stairs 50. good. That is, the laser sensor 40 of the third sensor group 33 may be part of the plurality of laser sensors 40 belonging to the second sensor group 32.

In the laser sensors 40 of the third sensor group 33, the distance between two adjacent laser sensors 40 in the vertical direction is set to a distance at which a walking person can be detected. For example, the separation distance is set to several tens of centimeters to several tens of centimeters.

The airbag device 20 includes an airbag 21 and a drive device 22 that generates gas (for example, nitrogen gas) to be injected into the airbag 21. The drive device 22 is connected to the power supply circuit 14 via a power supply line (not shown). The drive device 22 has a switching element 23 that turns on and off DC power supplied through the power supply line. The switching element 23 is connected to the communication bus 17 of the controller 12, and is turned on and off by a drive signal output from the controller 12. The controller 12 outputs a drive signal to drive the drive device 22 to generate gas. The generated gas inflates the airbag 21. That is, the controller 12 can inflate the plurality of airbags 21 individually by outputting a drive signal.

As the airbag 21, the airbag 21 has a mat shape that spreads in the horizontal direction when inflated, or a plate shape such as a rectangular parallelepiped shape or a disk shape. The width of the inflated airbag 21 is approximately the same as the width of the footboard 52. The depth of the inflated airbag 21 is greater than the depth of the footboard 52. Specifically, the depth of the inflated airbag 21 is set to be the length at which two or more inflated airbags 21 overlap in the vertical direction. In FIG. 3, the inflated airbag 21 is shown in broken lines. By overlapping the plurality of airbags 21 in the vertical direction, the airbag 21 can reliably catch a person who has fallen.

The plurality of airbag devices 20 are arranged on the inner surface side of the wall material 51 and attached to the wall material 51. The wall material 51 has a plurality of openings 34 through which each inflated airbag 21 pops out, as shown in FIG. The opening 34 is a horizontally long opening that extends in the horizontal direction (left-right direction in FIG. 3). The opening 34 is located slightly above each footboard 52. Moreover, the opening 34 is located between two laser sensors 40 adjacent to each other in the extension direction.

Hereinafter, the process executed by the control program 18 to detect a fall of a person will be described with reference to FIG. 4. First, the control program 18 supplies driving power to each laser sensor 40 of the third sensor group 33 and acquires the third detection information output by each laser sensor 40 of the third sensor group 33 (S11). The control program 18 then determines whether each laser sensor 40 of the third sensor group 33 has detected a person based on the acquired third detection information (S12). That is, the control program 18 determines whether a person has entered the entrance 53 or exit 54 of the stairs 50 in step S12.

When the control program 18 determines that no person has entered the entrance 53 or exit 54 of the stairs 50 (S12: No), it executes the process of step S11 again. The process of step S11 is repeatedly executed at every predetermined period stored in the memory 16. That is, the control program 18 periodically detects whether a person has entered the entrance 53 or exit 54 of the stairs 50. The predetermined period is, for example, from several milliseconds to about 1 second.

When the control program 18 determines that a person has entered the entrance 53 or exit 54 of the stairs 50 (S12: Yes), it supplies driving power to each laser sensor 40 of the second sensor group 32 (S14), Second detection information output from each laser sensor 40 of the second sensor group 32 is acquired (S15). The control program 18 then determines whether each laser sensor 40 of the second sensor group 32 has detected a person based on the acquired second detection information (S16).

When the control program 18 determines that the laser sensor 40 of the second sensor group 32 does not detect a person (S16: No), it stops supplying the driving power to the second sensor group 32 (S13), and performs step The process of S11 is executed again. For example, if a person walks to a position where the laser sensor 40 of the third sensor group 33 irradiates the laser beam and turns back, the control program 18 determines in step S16 that the person is not detected (S16: No). .

When the control program 18 determines that the laser sensor 40 of the second sensor group 32 has detected a person (S16: Yes), the control program 18 specifies the height and walking posture of the person walking at the entrance 53 or exit 54 of the stairs 50. (S17). To explain in detail, the control program 18 individually identifies the laser sensor 40 that has detected a person among the plurality of laser sensors 40 of the second sensor group 32, and places the laser sensor 40 at the highest position among the identified laser sensors 40. The height position of the laser sensor 40 is specified as the height. Note that the memory 16 previously stores, for example, a table in which the above-mentioned identification information given to each laser sensor 40 is associated with height. The control program 18 acquires the heights associated with the identified laser sensor 40, and specifies the tallest of the acquired heights as the height of the person walking at the entrance 53 or exit 54. Furthermore, the control program 18 specifies the walking posture as the "upright walking posture" in response to the plurality of laser sensors 40 that have detected a person being lined up in the vertical direction. The control program 18 specifies the walking posture as the "curved walking posture" in response to the fact that the plurality of laser sensors 40 that have detected the person are arranged in a substantially L-shape in the vertical and horizontal directions. That is, the control program 18 specifies the walking posture as "upright walking posture" or "curved walking posture."

The control program 18 corrects the threshold values A and B stored in the memory 16 based on the specified height and walking posture. The threshold values A and B are used to determine whether or not a person going up and down the stairs 50 is in a falling position (S24). The correction of the threshold values A and B and the determination of whether a person has fallen (S24) will be described in detail in step S24.

Note that the falling posture is not limited to the forward leaning posture, but includes other postures such as a hunched posture. A threshold value may be provided for each falling posture. Furthermore, the threshold value may be set as the amount of change in the numbers a and b. Based on the fact that the amount of change in the numbers a and b from the ascending and descending posture exceeds the threshold values A and B, the control program 18 determines that the person ascending and descending the stairs 50 will fall.

After executing the process of step S18, the control program 18 supplies driving power to each laser sensor 40 of the first sensor group 31 (S19), and reads the first detection information outputted by each laser sensor 40 of the first sensor group 31. (S20). Then, the control program 18 determines whether each laser sensor 40 of the first sensor group 31 has detected a person based on the acquired first detection information (S21). The first detection information output by each laser sensor 40 belonging to the first sensor group 31 is an example of individual detection information.

When the control program 18 determines that the laser sensor 40 of the first sensor group 31 does not detect a person (S21: No), it stops supplying driving power to the first sensor group 31 (S22), and performs step The process of S14 is executed again. For example, if a person who has entered the entrance 53 or exit 54 of the stairs 50 turns back, the control program 18 determines that no person is detected in step S21 (S21: No).

When the control program 18 determines that the laser sensor 40 of the first sensor group 31 has detected a person (S21: Yes), the control program 18 individually identifies the laser sensor 40 that detected the person based on the acquired first detection information. , the number a of the identified laser sensors 40 in the vertical direction and the number b of the identified laser sensors 40 in the horizontal direction are counted (S23).

The control program 18 uses the numbers a and b, which are count values, and the threshold values A and B corrected in step S18 to determine whether a person going up and down the stairs 50 will fall (S24). Correction of the threshold values A and B and determination of whether or not the subject is in a falling posture will be described in detail with reference to FIG. 5 .

FIG. 5(A) shows the laser sensors 40 that detected a person and their number when a person of a predetermined height and an upright walking posture ascends and descends the stairs 50, and the person whose height is shorter than the predetermined height and a curved walking posture. When a person goes up and down the stairs 50, the laser sensors 40 that detect a person and the number thereof are shown. FIG. 5(B) shows the laser sensors 40 that detect a person and the number thereof when a person of a predetermined height and an upright walking posture falls into a falling posture. FIG. 5C shows the laser sensors 40 that detected a person and the number of laser sensors 40 when a person who is shorter than a predetermined height and has a curved walking posture falls into a falling posture.

As shown in FIGS. 5A and 5B, when a person of a certain height changes from an upright walking posture to a falling posture, the number a of laser sensors 40 that detect the person in the vertical direction decreases from nine to six. However, the number b of laser sensors 40 that have detected a person in the horizontal direction increases from five to nine. The threshold values A and B are determined in advance, for example, by a test, and are stored in the memory 16 as values by which a fall can be determined for a person of a predetermined height and an upright walking posture. The threshold value A is, for example, "7", and the threshold value B is, for example, "7".

In step S24 (FIG. 4), the control program 18 determines that the posture is a falling position in response to the count value a being less than or equal to the threshold value A and the count value b being greater than or equal to the threshold value B (S24: Yes). ), and if the count value a is not less than the threshold value A or if the count value b is not more than the threshold value B, it is determined that the posture is not a fall (S24: No). The process in step S24 is an example of a determination process.

Next, correction of the threshold values A and B will be explained. The memory 16 stores in advance, for example, a first table that is a correspondence table for upright walking postures and a second table that is a correspondence table for curved walking postures. The first table and the second table are tables in which heights are associated with corrected threshold values A and B. Alternatively, the first table and the second table are tables that associate heights with correction values that can determine the corrected thresholds A and B. For example, if the walking posture specified in step S17 is an upright walking posture and the specified height is lower than a predetermined height, the thresholds A and B are corrected to values smaller than the original thresholds A and B. Further, if the walking posture specified in step S17 is a curved walking posture and the specified height is lower than the predetermined height, the thresholds A and B are values smaller than the original thresholds A and B, and when walking upright. It is corrected to a value that is even smaller than the corrected threshold values A and B for the posture. That is, the threshold values A and B are corrected according to the height and walking posture of the person going up and down the stairs 50. By correcting the threshold values A and B, the accuracy of detecting whether or not a person going up and down the stairs 50 is in a falling posture is improved.

As shown in FIG. 4, when the control program 18 determines that the posture is not a falling position (S24: No), it re-executes the processes from step S20 onwards. The process of step S20 is repeatedly executed at every predetermined period stored in the memory 16. That is, the control program 18 periodically acquires the first detection information and periodically determines whether or not a person will fall. The predetermined period is, for example, several milliseconds to several hundred milliseconds.

When the control program 18 determines that the person will fall (S24: Yes), the control program 18 specifies the height position of the person based on the first detection information acquired in step S20 (S25). Specifically, for example, the memory 16 stores in advance a table that associates identification information of the laser sensor 40 with height positions. The control program 18 acquires the height position corresponding to the identification information of the laser sensor 40 that detected the person, and specifies the lowest height position among the acquired height positions as the height position of the person. The process in step S25 is an example of position specifying process.

The control program 18 specifies the switching element 23 corresponding to the airbag 21 installed at a position lower than the specified height position (S26). Specifically, for example, the memory 16 stores in advance a table in which height positions and switching elements 23 are associated with each other. The control program 18 specifies the switching element 23 associated with a height position smaller than the specified height position.

The control program 18 outputs a drive signal to the specified switching element 23 (S27) to inflate the airbag 21. The control program 18 may inflate all of the airbags 21 located at a position lower than the specified height position, or may inflate only a predetermined number of airbags 21 from immediately below the specified height position. You may let them. The predetermined number is, for example, three, and is stored in the memory 16 in advance. The process in step S27 is an example of an operation process.

The control program 18 also sends an e-mail containing a text indicating that a person has fallen down the stairs 50 to the e-mail address stored in the memory 16 via the communication interface 13 (S28), and ends the process. Note that the person who visually recognizes the email checks the safety of the family member by, for example, using a telephone installed in the building or calling the family member in the building.

[Operations and effects of embodiment]
In this embodiment, the stair safety device 10 determines whether or not the person will fall before the person collides with the stairs 50 based on the person's posture, and activates the airbag 21 located below the person who is falling. . Therefore, it is possible to prevent a person falling from the stairs 50 from colliding with the stairs 50 or the floor under the stairs 50 and being injured.

In this embodiment, all the airbags 21 located below the height of the person who falls are activated at the same time. Further, the inflated airbags 21 are provided so as to be vertically overlapped. Therefore, the plurality of activated airbags 21 are stacked one on top of the other, making it possible to more reliably prevent injury to a person due to a fall.

In this embodiment, the plurality of laser sensors 40 and the airbag device 20 are attached to the wall material 51 and are integrated. Therefore, the work of installing the stair safety device 10 on the stairs 50 becomes easier.

In this embodiment, the inflated airbag 21 spreads out into a mat shape. Therefore, the inflated airbag 21 can reliably catch a person who has fallen.

[Modification 1]
In the embodiments described above, an example in which the stairs 50 are linear stairs has been described. In this modification, an example in which the stairs 50 are folded stairs will be described. Note that configurations and processes other than those described below are the same as those described in the embodiment.

In this modification, the plurality of laser sensors 40 belonging to the first sensor group 31 are attached to the ceiling located above the stairs 50, and the plurality of laser sensors 40 belonging to the second sensor group 32 and the third sensor group 33 are attached to the ceiling located above the stairs 50. 40 is attached to the ceiling located above the entrance (not shown) of the stairs 50 and the ceiling located above the exit 54.

The laser sensor 40 of the first sensor group 31 is attached to the ceiling in such a direction that it irradiates laser light vertically downward. That is, the plurality of laser sensors 40 of the first sensor group 31 have a detection area (first detection area) that is a space above the stairs 50 through which a person going up and down the stairs 50 passes. Note that in FIG. 2(B), the laser sensor 40 belonging to the first sensor group 31 is indicated by a circle filled with gray.

The plurality of laser sensors 40 belonging to the first sensor group 31 are arranged in the width direction of the stairs 50 (horizontal direction in FIG. 2(B)) and the depth direction of the stairs 50 (vertical direction in FIG. 2(B)), They are arranged in a so-called matrix or grid pattern.

The distance L2 between two adjacent laser sensors 40 in the width direction is, for example, the same dimension as the riser of the stairs 50, and is from several cm to several tens of cm, preferably from 10 cm to 20 cm. The distance D between two adjacent laser sensors 40 arranged in the horizontal direction is, for example, the same as the tread (depth of one step) of the stairs 50, or half the tread, and ranges from several cm to several tens of cm. , preferably from several cm to 20 cm.

A distance L1 between two laser sensors 40 adjacent to each other in the depth direction is shorter than a distance L2 between two laser sensors 40 adjacent to each other in the width direction. That is, the resolution in the depth direction is higher than the resolution in the width direction. The reason why the resolution in the depth direction is higher than the resolution in the width direction is to accurately detect that a person going up and down the stairs 50 is in a falling posture. The falling posture is, for example, a forward leaning posture and a posture that is elongated in the depth direction. By increasing the resolution in the depth direction, it is possible to accurately detect whether or not the user is in a falling position.

Similarly to the laser sensors 40 of the first sensor group 31, the laser sensors 40 of the second sensor group 32 are arranged in a matrix in the width direction and the depth direction so that the walking posture of a person entering the stairs 50 can be identified. They are arranged in a grid or grid pattern. Note that in FIG. 2(B), the laser sensor 40 belonging to the second sensor group 32 is indicated by an outlined circle.

The laser sensor 40 of the second sensor group 32 is installed on the ceiling in such a direction that it irradiates laser light vertically downward. That is, the plurality of laser sensors 40 of the second sensor group 32 detect the space above the hallway and floor of the entrance and exit 54 of the stairs 50, where a person entering the stairs 50 walks. second detection area).

The number of laser sensors 40 arranged in the depth direction and the width direction, that is, the length of the area in which the second sensor group 32 can detect a person in the vertical and horizontal directions in FIG. The laser beam is set so that it can simultaneously irradiate the top of the head and back of the person.

The laser sensor 40 of the third sensor group 33 is provided on the opposite side of the first sensor group 31 with the second sensor group 32 in between. The plurality of laser sensors 40 of the third sensor group 33 are arranged in a line surrounding the entrance and exit 54 of the stairs 50. In the example shown in FIG. 2(B), the plurality of laser sensors 40 of the third sensor group 33 are arranged in a substantially L-shape so as to surround the entrance and exit 54 of the stairs 50.

Further, the laser sensor 40 of the third sensor group 33 is attached to the ceiling in such a direction that it irradiates laser light vertically downward. Note that the laser sensor 40 of the third sensor group 33 may be used together with the laser sensor 40 of the second sensor group 32 to detect the walking posture of a person walking at the entrance and exit 54 of the stairs 50. That is, the laser sensor 40 of the third sensor group 33 may be part of the plurality of laser sensors 40 belonging to the second sensor group 32.

In the laser sensors 40 of the third sensor group 33, the distance between two adjacent laser sensors 40 is set to a distance at which a walking person can be detected. For example, the separation distance is set to several tens of centimeters to several tens of centimeters.

With reference to FIG. 6, the processing executed by the control program 18 in this modification will be described. Note that for processes similar to those in the embodiment, explanations will be omitted using the step numbers used in the embodiment. The same applies to other modified examples described later.

The control program 18 executes steps S11, S12, S14, S15, and S16 similarly to the embodiment. When the control program 18 determines in step S16 that the laser sensor 40 belonging to the second sensor group 32 has detected a person (S16: Yes), the control program 18 controls the climbing of the stairs 50 based on the second detection information acquired in step S15. The walking posture of a person walking at the exit or exit 54 is specified in the same manner as in the embodiment (S31). Then, the control program 18 uses the specified walking posture to correct the threshold value B stored in the memory 16 in the same manner as in the embodiment (S32).

Next, the control program 18 executes steps S19, S20, S21, and S22 in the same manner as in the embodiment. When the control program 18 determines that the laser sensor 40 belonging to the first sensor group 31 has detected a person (S21: Yes), the control program 18 determines whether the laser sensor 40 that detected the person has detected the person based on the first detection information acquired in step S20. The identification information is specified, and the number c of the specified laser sensors 40 lined up in the depth direction is counted in the same manner as in the embodiment (S33).

The control program 18 determines whether a person going up and down the stairs 50 will fall based on the counted number c and the correction value B corrected in step S32 (S34). Specifically, the control program 18 determines whether the number c is equal to or less than a threshold value B.

If the control program 18 determines that the number c is greater than the threshold value B and that the object will not fall (S34: No), it re-executes the processes from step S20 onwards. When the control program 18 determines that the number c is equal to or greater than the threshold value B and that the object will fall (S34: Yes), it executes the processes from step S25 onwards.

[Operation and effect of modification 1]
Even if the stairs 50 are turn-around stairs, the stair safety device 10 can detect a fall of a person before the person collides with the stairs 50.

Note that even if the stairs 50 are spiral stairs, the laser sensor 40 is provided on the ceiling as in this modification, so that the stair safety device 10 can detect a person's fall before the person crashes into the stairs 50. can do.

Moreover, even if the stairs 50 are linear like the embodiment, the laser sensor 40 may be attached to the ceiling.

[Modification 2]
In the embodiment described above, an example was described in which it is determined whether a person going up and down the stairs 50 will fall, using the counted numbers a and b and the threshold values A and B stored in the memory 16. In this modification, an example will be described in which the posture of a person going up and down the stairs 50 is drawn on an image to determine whether or not the person will fall. Note that configurations and processes other than those described below are the same as those described in the embodiment.

In this modification, the control program 18 includes a drawing module that draws an image. The control program 18 can pass position information indicating the position to the drawing module and acquire image data indicating the image drawn by the drawing module. Note that the drawing module may be a separate program from the control program 18.

The memory 16 stores judgment image data (FIG. 1) in place of the threshold values A and B in advance. The judgment image data is data indicating a judgment image that is an image of the external shape of a person in a falling posture. The judgment image is, for example, an image showing the outline of a person leaning forward, an image showing the outline of a person hunched over, or the like. The memory 16 also stores judgment image data corresponding to the upright posture and judgment image data corresponding to the curved walking posture.

Further, the memory 16 stores in advance a first correspondence table in which identification information and position information of each laser sensor 40 are associated with each other, and a second correspondence table in which heights are associated with enlargement/contraction ratios.

The control program 18 executes the processes from steps S11 to S17 shown in FIG. 4, and specifies the height and walking posture of the person who has entered the entrance 53 and exit 54 of the stairs 50 (S17). Then, the control program 18 executes a process of specifying a judgment image and correcting the specified judgment image, instead of the process of step S18. To explain in detail, the control program 18 identifies judgment image data indicating a judgment image corresponding to the walking posture specified in step S17 from among the plurality of judgment image data stored in the memory 16. Furthermore, the control program 18 specifies the enlargement/contraction ratio associated with the height specified in step S17 in the second correspondence table. The control program 18 corrects the judgment image by enlarging or reducing it using the specified enlargement/reduction ratio.

Next, the control program 18 executes the processes from steps S19 to S22, and if it is determined in step S21 that a person has entered the stairs 50 (S21: Yes), the first detection information acquired in step S20, Using the corrected judgment image, it is judged whether or not a person going up and down the stairs 50 will fall (S24). To explain in detail, the control program 18 specifies the identification information of the laser sensor 40 that detected the person based on the first detection information acquired in step S20, and uses the position information associated with the specified identification information as the first detection information. Specify in the correspondence table. Then, the control program 18 passes the specified position information to the drawing module, and causes the drawing module to generate image data showing the external shape of the person on the stairs 50. The control program 18 uses pattern matching or the like to calculate the number or proportion of points of agreement or difference between the external shape of the person shown in the image data generated by the drawing module and the external shape of the person shown in the corrected judgment image. The control program 18 is based on the fact that the number or proportion of matching points is greater than or equal to a threshold value stored in advance in the memory 16, or on the basis that the number or proportion of differences is less than a threshold value stored in advance in the memory 16. Based on this, it is determined that a person going up and down the stairs 50 will fall (S24: Yes).

If the control program 18 determines that the person going up and down the stairs 50 will not fall (S24: No), it re-executes the processes from step S20 onwards. That is, the control program 18 periodically acquires the first detection information and periodically determines whether or not a person going up and down the stairs 50 will fall. When the control program 18 determines that the person going up and down the stairs 50 will fall (S24: Yes), the control program 18 specifies the height position of the person based on the image data that is the first detection information acquired in step S20 (S25). . Specifically, the control program 18 identifies the stepboard 52 where the person is located from the image indicated by the image data. Then, the control program 18 specifies the height position corresponding to the specified stepboard 52. The control program 18 uses the specified height position to execute the processes from step S26 onwards in the same manner as in the embodiment.

[Operation and effect of modification example 2]
In this modified example, since a fall is determined based on whether the external shape of the person going up and down the stairs 50 matches the outside shape of the person in the falling posture, the length of the person going up and down the stairs 50 in the vertical and horizontal directions is determined. The accuracy of determining whether or not to fall is better than in the embodiment in which it is determined whether or not to fall based on a change in height.

In this embodiment, the height and walking posture of the person going up and down the stairs 50 are used to specify and correct the judgment image stored in the memory 16, and the corrected judgment image is used to determine whether the person going up and down the stairs 50 falls. Decide whether or not to do so. Therefore, compared to the case where the determination image is not specified and corrected using the height and walking posture of the person going up and down the stairs 50, the stair safety device 10 can improve the accuracy of determining whether or not the person is in a falling posture.

[Modification 3]
In the above embodiment, an example using the laser sensor 40 has been described. In this modification, an example will be described in which a human sensor 60 (FIG. 7) is used instead of the laser sensor 40. Note that configurations and processes other than those described below are the same as those described in the embodiment.

The stair safety device 10 includes a first sensor group 31 having a plurality of human detection sensors 60 instead of the laser sensor 40, a second sensor group 32 having a plurality of human detection sensors 60 instead of the laser sensor 40, and a laser sensor. A third sensor group 33 having a plurality of human detection sensors 60 in place of the sensor 40 is provided. The human sensor 60 is connected to the power supply circuit 14 by a power supply line through a switching element, and is also connected to the communication bus 17 of the controller 12 .

The human sensor 60 is a sensor that detects infrared rays emitted by a person. In the following, an example will be described in which a type of human sensor 60 having a plurality of small detection areas 61 (FIG. 7(A)) is used. Specifically, the human sensor 60 includes a plurality of light receiving parts that receive infrared rays and output a voltage according to the intensity of the received infrared rays, and a plurality of light receiving sections that collect infrared rays incident from each of the small detection areas 61 to detect each infrared ray. It has a lens group that respectively emits light to the light receiving section. Alternatively, the human sensor 60 includes a plurality of light receiving sections and a lens group that collects the infrared rays incident from each of the small detection areas 61 and emits the infrared rays incident on the light receiving sections, respectively. outputs a voltage according to the change in intensity.

The human sensor 60 includes first identification information for individually identifying the plurality of human sensors 60, second identification information for individually identifying the plurality of small detection areas 61, and information indicating whether infrared rays have been detected. Outputs detection information including . The control program 18 into which the detection information has been input specifies whether or not a person has been detected for each person detection sensor 60 and each small detection area 61. Among the detection information output by the human sensor 60, the information identified by the second identification information and indicating whether infrared rays have been detected is an example of individual detection information.

As shown in FIG. 7(A), the first sensor group 31 includes a plurality of human detection sensors 60. The human sensor 60 of the first sensor group 31 is a sensor for detecting whether a person going up and down the stairs 50 has fallen. The human sensor 60 of the first sensor group 31 is attached to the wall material 51. To explain in detail, the plurality of human detection sensors 60 are each attached to the wall material 51 in such a direction that the detection area is the space above the stairs 50 where people go up and down. Further, the plurality of human detection sensors 60 are spaced apart from each other at intervals such that the entire space above the stairs 50 where people go up and down is used as a detection area. The interval is set depending on the width of the detection area of the human sensor 60 used. The detection area of the human sensor 60 is a combined area of a plurality of small detection areas 61. In the example shown in FIG. 7A, a part of the plurality of small detection areas 61 of one person detection sensor 60 and a part of the plurality of small detection areas 61 of another person detection sensor 60 are are overlapping with each other. Each small detection area 61 included in the human sensor 60 is an example of an individual detection area.

The human detection sensor 60 of the second sensor group 32 is a sensor for detecting a person who has entered the entrance 53 and exit 54 of the stairs 50, and also for detecting the height and walking posture of the person entering the stairs 50. . That is, the second sensor group 32 of this modification has both the function that the second sensor group 32 in the embodiment has and the function that the third sensor group 33 has.

The human sensor 60 of the second sensor group 32 is a part of the wall material 51 and is attached to a portion adjacent to the entrance 53 and exit 54 of the stairs 50, respectively. To explain in detail, each person detection sensor 60 is attached to the wall material 51 in such a direction that the detection area is a space where a person walks through the entrance 53 and a space where a person walks through the exit 54. Further, as the individual person detection sensor 60, a person detection sensor is used which has a detection area large enough to cover the space where a person walks through the entrance 53 and the space where a person walks through the exit 54. ing. Note that if the detection area of the human sensor 60 is narrow, a plurality of human sensors 60 may be arranged at each of the entrance 53 and exit 54 .

The control program 18 executes the process shown in FIG. 8 instead of the process shown in FIG. To explain in detail, first, the control program 18 supplies driving power to each of the human detection sensors 60 of the second sensor group 32, and acquires second detection information output from each of the human detection sensors 60 of the second sensor group 32. (S15). The control program 18 determines whether a person has entered the entrance 53 or exit 54 of the stairs 50 based on the acquired second detection information (S16). The control program 18 periodically repeats the process of step S15 until the human sensor 60 of the second sensor group 32 detects a person (S16: No, S15).

When the control program 18 determines that a person has entered the entrance 53 or exit 54 of the stairs 50 (S16: Yes), it executes the processes of steps S17 and S18 in the same manner as in the embodiment. That is, the control program 18 uses the second detection information acquired in step S15 to identify the height and walking posture of the person who has entered the entrance 53 or exit 54 of the stairs 50, and adjusts the height and walking posture to the specified height and walking posture. Based on this, the threshold values A and B stored in the memory 16 are corrected.

Next, the control program 18 executes steps S19, S20, S21, and S22 in the same manner as in the embodiment. That is, the control program 18 drives each person detection sensor 60 of the first sensor group 31 (S19) to acquire first detection information (S20), and based on the acquired first detection information, moves the person to the stairs 50. It is determined whether a person has entered (S21).

When the control program 18 determines that a person has entered the stairs 50 (S21: Yes), it executes the processes of steps S23 and S24 in the same manner as in the embodiment. That is, the control program 18 determines, based on the first detection information acquired in step S20, the number a of the small detection areas 61 in which a person is detected in the vertical direction, and the number b of the small detection areas 61 in which a person is detected in the horizontal direction. , and using the counted numbers a and b and the correction values A and B corrected in step S18, it is determined whether or not a person going up and down the stairs 50 will fall, in the same manner as in the embodiment. (S24). When the control program 18 determines that the user will not fall (S24: No), the control program 18 repeatedly executes the processes from steps S20 to S24. When the control program 18 determines that the user will fall (S24: Yes), the control program 18 executes the processes from step S25 onward in the same manner as in the embodiment.

[Operation and effect of modification 3]
In this modification, using the human sensor 60, it is possible to detect whether or not a person will fall from the stairs 50 before the person collides with the tread 52 of the stairs 50, the floor below, or the like.

In addition, when the stairs 50 are turn-around stairs, the human sensor 60 may be attached to the ceiling located above the stairs 50, as shown in FIG. 7(B).

[Modification 4]
In the embodiment described above, an example was described in which the laser sensor 40 is used to determine whether a person going up and down the stairs 50 will fall. In this modification, an example will be described in which a camera is used to determine whether or not a person going up and down the stairs 50 will fall. Furthermore, in this modification, an example will be described in which two laser sensors 40 are used to detect whether or not a person has entered the entrance and exit 54 of the stairs 50. Note that configurations and processes other than those described below are the same as those described in the embodiment. Moreover, below, the stair safety device 10 in case the stairway 50 is a turn-back stairway will be explained.

The stair safety device 10 includes cameras 62 and 63 (FIG. 1) and a pair of laser sensors 40 (FIG. 9(A)) instead of the sensor groups 31, 32, and 33. The cameras 62 and 63 and the laser sensor 40 are connected to the power supply circuit 14 by a power supply line through switching elements, and are also connected to the communication bus 17 of the controller 12. That is, the control program 18 can supply drive power to the cameras 62 and 63 to cause the cameras 62 and 63 to take images, and can acquire image data generated by the images taken by the cameras 62 and 63. Further, the control program 18 can supply driving power to the laser sensor 40 to detect a person.

The memory 16 stores in advance the plurality of judgment image data described in the second modification.

The cameras 62 and 63 are attached to a wall 56 adjacent to the folded portion 55 of the stairs 50, as shown in FIG. 9(A). Specifically, the camera 62 is attached to the wall 56 in such a direction that the space above the footboard 52 located above the folded portion and the exit 54 are imaged. The camera 63 is attached to the wall 56 in such a direction that its imaging area is the space above the stepboard 52 located below the folded portion and the entrance (not shown).

One of the pair of laser sensors 40 is attached to a wall 57 adjacent to the exit 54 of the stairs 50, and the other is attached to a wall (not shown) adjacent to the entrance of the stairs 50. The pair of laser sensors 40 are arranged in such a direction that they respectively irradiate laser beams toward the entrance and exit 54 of the stairs 50 so as to be able to detect people entering the entrance and exit 54 of the stairs 50.

The control program 18 executes the process shown in FIG. 10 instead of the process shown in FIG. To explain in detail, the control program 18 supplies driving power to the pair of laser sensors 40 and acquires the fourth detection information output by the laser sensors 40 (S41). The control program 18 determines whether a person has entered the entrance and exit 54 of the stairs 50 based on the acquired fourth detection information (S12). The control program 18 periodically executes the process of step S41 until it is determined that a person has entered the entrance and exit 54 of the stairs 50 (S12: No, S41).

When the control program 18 determines that a person has entered the entrance and exit 54 of the stairs 50 (S12: Yes), it supplies driving power to the cameras 62 and 63 and causes the cameras 62 and 63 to take images (S42). ). Then, the control program 18 acquires image data generated by imaging by the cameras 62 and 63 (S43). The control program 18 generates external image data of the imaged object based on the acquired image data. For example, the control program 18 performs binarization processing on the acquired image data, and acquires information indicating the exterior shape as the exterior shape image data, with the portion where the value changes as the exterior shape of the imaged object (S44). Note that the control program 18 determines that there is no person on the stairs 50 when the external image data cannot be acquired.

The control program 18 determines whether a person has entered the stairs 50 based on the acquired external image data (S45). When the control program 18 determines that no person has entered the stairs 50 (S45: No), it stops supplying driving power to the cameras 62 and 63 (S46), and re-executes the processes from step S41 onwards.

When the control program 18 determines that a person has entered the stairs 50 (S45: Yes), it determines whether the person going up and down the stairs 50 will fall (S47). To explain in detail, the control program 18 determines the number of points of agreement or difference between the outer shape image shown by the outer shape image data acquired in step S44 and the human outer shape in the judgment image shown by the judgment image data stored in the memory 16. The ratio is calculated using pattern matching or the like. The control program 18 is based on the fact that the number or proportion of matching points is greater than or equal to a threshold value stored in advance in the memory 16, or on the basis that the number or proportion of differences is less than a threshold value stored in advance in the memory 16. Based on this, it is determined that a person going up and down the stairs 50 will fall (S47: Yes).

If the control program 18 determines that the person going up and down the stairs 50 will not fall (S47: No), it re-executes the processes from step S43 onwards. That is, the control program 18 periodically acquires image data and periodically determines whether or not a person going up and down the stairs 50 will fall. When the control program 18 determines that a person going up and down the stairs 50 will fall (S47: Yes), it executes the processes of steps S25 and S26 in the same manner as in the embodiment.

[Operation and effect of modification 4]
In this modification, using the cameras 62 and 63, it is possible to detect whether or not a person will fall from the stairs 50 before the person collides with the tread 52 of the stairs 50, the floor below, or the like.

Furthermore, in this modification, it can be determined by the two laser sensors 40 whether or not a person has entered the entrance and exit 54 of the stairs 50.

Further, in this modification, when a person enters the entrance 53 or exit 54 of the stairs 50, driving power is supplied to the cameras 62 and 63. Therefore, compared to the case where driving power is always supplied to the cameras 62 and 63, the stair safety device 10 can reduce the power consumption required to detect a fall of a person going up and down the stairs 50.

In this modification, an example in which the stairs 50 are folded stairs has been described. However, the stairs 50 may also be straight stairs. In that case, only one camera 62 is provided on the stairs 50.

[Modification 5]
In the above-mentioned modification 4, an example was described in which the cameras 62 and 63 are used to image a person going up and down the stairs 50. In this modification, an example will be described in which the three-dimensional laser sensors 64 and 65 (FIG. 1) are used to image a person going up and down the stairs 50. Note that configurations and processes other than those described below are the same as those described in Modification 4.

The stair safety device 10 includes three-dimensional laser sensors 64 and 65 instead of cameras 62 and 63. The three-dimensional laser sensors 64 and 65 irradiate a detection area with scanning light (laser light), receive reflected light reflected by an object, generate image data based on the received reflected light, and generate image data. This is a sensor that outputs The three-dimensional laser sensor 64 is attached to the wall 56 (FIG. 9(A)) in the same manner as the camera 62, and uses the space above the tread 52 located above the folded portion 55 and the exit 54 as its detection area. . The three-dimensional laser sensor 65 is attached to the wall 56 in the same manner as the camera 63, and its detection area is the space above the footboard 52 located below the folded portion 55 and the entrance.

The control program 18 performs processing similar to the processing shown in FIG. 10 to determine whether the posture of the person going up and down the stairs 50 is a falling posture (S47).

[Operation and effect of modification 5]
In this modification, using the three-dimensional laser sensors 64 and 65, it is possible to detect whether or not a person will fall from the stairs 50 before the person collides with the tread 52 of the stairs 50 or the floor below. .

[Modification 6]
In the embodiment described above, an example using a plurality of laser sensors 40 has been described. However, instead of the multiple laser sensors 40, multiple acoustic sensors 70 may be used. Note that configurations and processes other than those described below are the same as those described in the embodiment.

The stair safety device 10 includes a first sensor group 71, a second sensor group 72, and a third sensor group 73 shown by broken lines in FIG. 1 in place of the sensor groups 31, 32, and 33 described in the embodiment. . The first sensor group 71, the second sensor group 72, and the third sensor group 73 each include a plurality of sound wave sensors 70.

The acoustic wave sensor 70 is a sensor that irradiates a detection area with a acoustic wave and receives a reflected wave reflected by an object. The sound wave sensor 70 outputs detection information including identification information, information indicating the difference between the timing at which the sound wave was irradiated and the timing at which the reflected wave was received, and information indicating a voltage value according to the intensity of the received sound wave. do. Note that the plurality of sound wave sensors 70 are prevented from interfering with each other by, for example, making the frequencies of the sound waves they emit different from each other or increasing the directivity of the sound waves they emit.

The sound wave sensor 70 is installed in the same manner as the laser sensor 40 described in the embodiment, and emits sound waves toward the entrance 53 and exit 54 of the stairs 50 and the space above the stairs 50, and collects detection information. input to the controller 12.

The control program 18 performs a process similar to the process shown in FIG. 4 to determine whether a person going up and down the stairs 50 will fall (S24).

[Operation and effect of modification 6]
In this modification, using the sonic sensor 70, it is possible to detect whether or not a person will fall from the stairs 50 before the person collides with the tread 52 of the stairs 50, the floor below, or the like.

[Modification 7]
In this modification, an example will be described in which the airbag device 20 is arranged in a space below the tread 52 of the stairs 50, as shown in FIG. 9(B). A plurality of risers 58 included in the stairs 50 each have an opening through which the inflated airbag 21 pops out.

The broken line in FIG. 9(B) indicates the inflated airbag 21. The airbag 21 has a shape in which a plurality of airbags 21 overlap in the extending direction in the inflated state. Specifically, the airbag 21 has a long shape in the direction in which it pops out. By overlapping the plurality of airbags 21 in the vertical direction, the airbag 21 can reliably catch a person who has fallen.

[Other variations]
In the embodiment described above, an example was explained in which the laser sensor 40 that irradiates one laser beam is used. However, instead of the laser sensor 40, a laser sensor that emits a plurality of laser beams may be used. The laser sensor has a plurality of small detection areas 61 similarly to the human sensor 60 described in the third modification. Even when this type of laser sensor is used, it is possible to detect whether or not a person will fall down the stairs 50 before the person collides with the tread 52 of the stairs 50 or the floor below.

In the above-described embodiment, an example has been described in which it is determined whether or not a person will fall depending on whether or not the posture of the person going up and down the stairs 50 is in a falling posture. However, in addition to the posture of the person going up and down the stairs 50, it may be determined whether the person will fall based on the moving speed of the person going up and down the stairs 50. For example, the control program 18 periodically acquires the position information indicated by the identification information of the laser sensor 40 that detected the person based on the first detection information periodically acquired, and calculates the position per unit time of the position indicated by the position information. The moving speed of the person going up and down the stairs 50 is calculated based on the moving distance. The control program 18 then determines that the posture of the person indicated by the acquired first detection information is a falling posture, and the calculated moving speed of the person is greater than or equal to the first threshold and less than the second threshold (<first threshold). In this case, it is determined that there is a risk that a person going up and down the stairs 50 may fall. In addition to the posture of the person indicated by the first detection information, it is determined whether a person going up or down the stairs 50 will fall based on the person's movement speed, so it is possible to detect a person's fall with higher accuracy. .

In the above-described embodiment, an example has been described in which it is determined whether or not a person will fall depending on whether or not the posture of the person going up and down the stairs 50 is in a falling posture. However, it may be determined based on the amount of change in the posture of the person going up and down the stairs 50 whether there is a risk that the person going up and down the stairs 50 will fall. The control program 18 periodically specifies the posture of the person based on the acquired first detection information, and calculates the amount of change in the specified posture per unit time. The control program 18 determines whether the calculated amount of change per unit time is greater than or equal to a threshold value stored in advance in the memory 16, and in response to the amount of change per unit time being greater than or equal to the threshold value, the control program It is determined that a person going up and down 50 will fall. Further, in addition to the moving speed of the person, it may be determined whether the person will fall based on the acceleration of the person.

10... Fall detection device 12... Controller 16... Memory 20... Air bag device 21... Air bag 22... Drive device 40... Laser sensor 50... Stairs 51...・Wall material 60...Human detection sensor 61...Small detection areas 62, 63...Cameras 64, 65...Three-dimensional laser sensor 70...Sound wave sensor

Claims (6)

A detection device that uses a space through which a person passes when going up and down stairs as a detection area, and outputs detection information that can identify a person's posture or change in posture and position;
a plurality of airbag devices arranged on the staircase or on the side of the staircase and arranged along the direction in which the plurality of treads of the staircase are arranged;
a controller into which the detection information is input and which is capable of outputting a drive signal that individually activates each of the airbag devices;
The above airbag device is
It has a drive device and an airbag inflated by the drive device,
The inflated airbag has a depth greater than the depth of the treadle, and has a mat-like upper surface that expands in the horizontal direction. It is used to prevent people from falling downward,
The above controller is
a determination process for determining whether a person going up and down the stairs will fall based on the input detection information;
Based on the determination that the person will fall, all of the airbag devices located below the height of the person indicated by the detection information, and which are located below the height of the person indicated by the detection information. A stair safety device that performs an activation process that simultaneously outputs a drive signal to the device . The detection device is a plurality of sensors that respectively irradiate sound waves or laser light and receive or receive sound waves or laser light reflected by the person,
The stair safety device according to claim 1 , further comprising a wall material that holds the plurality of sensors arranged apart from each other and the airbag device arranged between the sensors in the vertical direction. The detection device is a plurality of laser sensors arranged above or to the side of the stairs,
Each of the above laser sensors irradiates each of a plurality of individual detection areas obtained by dividing the above detection area with laser light, receives reflected light of the irradiated laser light, and provides individual detection information and identification according to the received reflected light. It is a sensor that outputs information,
The judgment process is a process of identifying the identification information of the laser sensor that detected the person based on the individual detection information and the identification information, and determining whether or not the person will fall based on the identified identification information. The stair safety device according to claim 1 or 2 . The detection device is a human detection sensor capable of individually detecting infrared rays incident from a plurality of individual detection areas obtained by dividing the detection area, or a human detection sensor capable of detecting changes in infrared rays incident from the individual detection areas. and a sensor that outputs the detection information including individual detection information and individual identification information for each individual detection area,
The stair safety device according to claim 1 or 2 , wherein the judgment process is a process of judging whether or not a person will fall based on the individual detection information and the individual identification information. The detection device is a three-dimensional laser sensor that irradiates the detection area with scanning light, receives reflected light of the scanning light, and outputs image data generated based on the received reflected light as the detection information,
The controller has a memory that stores judgment image data indicating a falling posture,
The above judgment process is a process of judging whether or not the person will fall based on the points of agreement or differences between the image of the person shown by the inputted image data and the image of the person in the falling posture shown by the judgment image data. A stair safety device according to claim 1 or 2 . The detection device is a camera that images the stairs and the space above the stairs and outputs image data,
The controller has a memory that stores judgment image data indicating a falling posture,
The above judgment process is a process of judging whether or not the person will fall based on the points of agreement or differences between the image of the person shown by the inputted image data and the image of the person in the falling posture shown by the judgment image data. can be,
The stair safety device according to claim 1 or 2 , wherein the controller further executes a position specifying process for specifying the height position of the person who is determined to fall based on the image shown by the image data.

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