KR101862455B1 - Apparatus and method for detecting movement on stairs - Google Patents

Apparatus and method for detecting movement on stairs Download PDF

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KR101862455B1
KR101862455B1 KR1020160030080A KR20160030080A KR101862455B1 KR 101862455 B1 KR101862455 B1 KR 101862455B1 KR 1020160030080 A KR1020160030080 A KR 1020160030080A KR 20160030080 A KR20160030080 A KR 20160030080A KR 101862455 B1 KR101862455 B1 KR 101862455B1
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South Korea
Prior art keywords
altitude information
altitude
movement
observer
time interval
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KR1020160030080A
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Korean (ko)
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KR20170106681A (en
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임순
천세범
허문범
임덕원
남기욱
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한국항공우주연구원
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
    • G01C21/00—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00
    • G01C21/20—Instruments for performing navigational calculations
    • G01C21/206—Instruments for performing navigational calculations specially adapted for indoor navigation
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
    • G01C5/00—Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels
    • G01C5/06—Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L1/00—Measuring force or stress, in general
    • G01L1/02—Measuring force or stress, in general by hydraulic or pneumatic means

Abstract

An apparatus for detecting interlayer movement of a user using a pressure sensor is provided. The apparatus includes: a collecting unit for acquiring at least one altitude information according to a position of an observer moving in a target space for a predetermined time period; a first altitude information at a start point of the time interval and an end of the time interval A determination unit configured to calculate a change amount between the first altitude information at the point and a second altitude information at the point and to determine whether or not the object to be observed is moved between layers based on the calculation result; And a processing unit for updating the altitude error.

Description

[0001] APPARATUS AND METHOD FOR DETECTING MOVEMENT ON STAIRS [0002]

The present invention relates to a technique for tracking a layer movement state of a user in a specific space, and more particularly to an apparatus and method for detecting a user's interlayer movement using a pressure sensor.

Generally, in the process of tracking the position of a person to be tracked, which is moving in a specific space, the floor movement state of the person to be tracked is tracked by using the infrastructure built for each floor or by using a walking navigation system do. Both methods have an advantage in that they can be continuously tracked by relatively simple equipment, but there is a limit in that the error probability is large. In the case of using the infrastructure constructed for each floor, the floor moving state is determined by detecting the entry of the target person through the equipment installed in each floor such as the wireless AP, , It is impossible to track the layer movement status in an emergency such as a disaster. In the case of the method using the walking navigation method, the motion such as the walking motion of the subject is recognized using the acceleration and the angular velocity measured through the inertial sensor to determine the interlayer movement. In this process, It is difficult to provide accurate interlayer movement information due to erroneous detection of the layer movement error and layer movement determination errors due to individual walking characteristics. For this reason, there is a need for a technique capable of increasing the accuracy of interlayer movement detection in a specific space.

According to one aspect, there is provided an apparatus for detecting interlayer movement of a user using a pressure sensor. The apparatus includes: a collecting unit for acquiring at least one altitude information according to a position of an observer moving in a target space for a predetermined time period; a first altitude information at a start point of the time interval and an end of the time interval A determination unit configured to calculate a change amount between the first altitude information at the point and a second altitude information at the point and to determine whether or not the object to be observed is moved between layers based on the calculation result; And a processing unit for updating the altitude error.

Here, the altitude information may include an altitude value calculated corresponding to pressure information measured from a pressure sensor attached to one side of the observer.

According to one embodiment, the collecting unit may acquire the at least one altitude information whenever the movement of the observer occurs.

Also, the first altitude information may be altitude information that reflects the altitude error of the previous section of the time period with respect to the altitude value measured at the start point.

According to one embodiment, the determination unit may calculate the change amount by dividing a difference value between the first altitude information and the second altitude information by the number of altitude information collected during the time interval.

At this time, the determination unit determines that the inter-layer movement of the observer is caused when the amount of change between the first altitude information and the second altitude information is equal to or greater than a predetermined threshold value.

According to one embodiment, the processing unit may further determine whether or not the observer is in a layer movement, and calculate the altitude error using the difference between the altitude information just before the layer movement occurs and the second altitude information It can be continuously updated.

According to another aspect, there is provided a method of detecting a user's interlayer movement using a pressure sensor. The method includes the steps of: obtaining at least one altitude information according to a position of an observer moving in a subject space for a predetermined time period; determining a first altitude information at a start point of the time interval and an ending point Calculating an amount of change between the first altitude information and the second altitude information on the basis of the calculation result and determining whether the object to be observed is moved between layers based on the calculation result; And the like.

According to one embodiment, the altitude information may include an altitude value calculated corresponding to pressure information measured from a pressure sensor attached to one side of the observer.

According to one embodiment, the step of acquiring the at least one altitude information may acquire the at least one altitude information whenever the movement of the observer occurs.

In this case, the first altitude information may be altitude information that reflects an altitude error with respect to a previous section of the time section with respect to an altitude value measured at the starting point.

According to one embodiment, the step of determining whether or not the interlayer movement is performed may include calculating a difference between the first altitude information and the second altitude information by the number of altitude information collected during the time interval, have.

In addition, the step of determining whether or not the inter-story movement determines whether inter-story movement of the observer is generated when the amount of change between the first and the second altitude information is equal to or greater than a predetermined threshold value.

According to an embodiment, the step of updating the altitude error with respect to the time interval may further include: determining whether the observer is in the layer movement, and further determining whether the altitude information immediately before the layer movement occurs and the second altitude information The altitude error can be continuously updated using the difference value.

1 is a block diagram showing an interlayer motion detection apparatus according to an embodiment.
Fig. 2 is a view for explaining a problem of layer error detection caused by an altitude error. Fig.
3 is a flow chart showing an interlayer movement detection method according to an embodiment.
FIG. 4 is a view for explaining a detailed process of tracked interlayer movement detection according to an embodiment.

It is to be understood that the specific structural or functional descriptions of embodiments of the present invention disclosed herein are presented for the purpose of describing embodiments only in accordance with the concepts of the present invention, May be embodied in various forms and are not limited to the embodiments described herein.

Embodiments in accordance with the concepts of the present invention are capable of various modifications and may take various forms, so that the embodiments are illustrated in the drawings and described in detail herein. However, it is not intended to limit the embodiments according to the concepts of the present invention to the specific disclosure forms, but includes changes, equivalents, or alternatives falling within the spirit and scope of the present invention.

The terms first, second, or the like may be used to describe various elements, but the elements should not be limited by the terms. The terms may be named for the purpose of distinguishing one element from another, for example without departing from the scope of the right according to the concept of the present invention, the first element being referred to as the second element, Similarly, the second component may also be referred to as the first component.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between. Expressions that describe the relationship between components, for example, "between" and "immediately" or "directly adjacent to" should be interpreted as well.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, the terms " comprises ", or " having ", and the like, are used to specify one or more of the features, numbers, steps, operations, elements, But do not preclude the presence or addition of steps, operations, elements, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the meaning of the context in the relevant art and, unless explicitly defined herein, are to be interpreted as ideal or overly formal Do not.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, the scope of the patent application is not limited or limited by these embodiments. Like reference symbols in the drawings denote like elements.

1 is a block diagram showing an interlayer motion detection apparatus 100 according to an embodiment.

The interlayer movement detecting apparatus 100 is a means for real-time detecting a layer moving state using a pressure sensor worn on one side of a body of a person to be observed moving in a specific space, The accuracy of the inter-layer movement determination of the observer can be improved by continuously reflecting the relative altitude error. The interlayer movement detecting apparatus 100 may include a collecting unit 110, a determining unit 120, and a processing unit 130.

First, the collecting unit 110 may acquire at least one altitude information according to a position of an observer moving in a target space for a predetermined time period. The at least one altitude information includes an altitude value calculated corresponding to pressure information measured from a pressure sensor attached to one side of the observer. At this time, the collecting unit 110 may acquire the at least one altitude information whenever the movement of the observer occurs. The pressure sensor may transmit the at least one altitude information to the interlayer movement detection apparatus 100 using a wireless communication scheme such as Wi-Fi, Bluetooth, NFC (Near Field Communication) .

The determination unit 120 may determine whether the object to be observed is moved between layers based on the altitude change amount in the time interval. For this, the determination unit 120 calculates a change amount between the first altitude information at the start point of the time interval and the second altitude information at the end point of the time interval, and based on the calculation result, It is judged whether or not the subject moves between layers. In this case, the first altitude information can be understood as altitude information in which an altitude error with respect to a previous section of the time interval is reflected to an altitude value measured at a start point of the time interval.

The determination unit 120 may calculate a change amount between the first altitude information and the second altitude information using a window function method. For example, the determination unit 120 calculates the amount of change by dividing a difference value between the first altitude information and the second altitude information by the number of altitude information collected during the time period. In addition, the determination unit 120 may determine that the inter-layer movement of the observer has occurred when the amount of change between the first altitude information and the second altitude information is equal to or greater than a predetermined threshold value.

The processing unit 130 may update the altitude error with respect to the time interval if it is determined that the inter-layer movement of the observer has occurred, as a result of the determination unit 120. [ In this case, the processing unit 130 may further determine whether the observer is in the layer movement, and if the observer is determined to be in the layer movement, And continuously updates the altitude error using the difference value.

The interlayer movement detection apparatus 100 detects the interlayer movement of the observer by using the altitude information measured through the pressure sensor, and uses the altitude information immediately before the layer movement as the altitude error value for the altitude information correction after the layer movement Thereby making it possible to increase the accuracy of the determination of the layer moving state. Also, the interlayer movement detection apparatus 100 can minimize the layer movement state detection error due to the malfunction of the pressure sensor by measuring the altitude information only when the actual movement of the measurement subject occurs.

Fig. 2 is a view for explaining a problem of layer error detection caused by an altitude error. Fig.

In order to compensate the limitations of the process of tracking the floor movement using the existing method (using the infrastructure constructed by each floor of the building or using the walking navigation system using the inertial sensor), the interlayer movement detection device The altitude information is measured using a pressure sensor worn on one side and the layer movement state is detected by using the measured altitude information. This is based on the characteristic that the atmospheric pressure decreases to a certain level according to the altitude change. The pressure information measured by the pressure sensor based on the standard atmospheric pressure-altitude correlation is converted into altitude information And convert the converted altitude information into the layer position of the object to be observed again.

However, in the case of the pressure sensor, there is still a possibility of error in measuring the altitude information of the observer due to high temperature and high pressure in an emergency such as initial bias, fire, and disaster. In FIG. 2 (a), if the temporal temperature or the atmospheric pressure is abnormally measured, an error may occur as shown at 210 in the altitude information conversion process in which the observer is located. In this case, since the altitude error generated in the altitude information conversion process is directly used for the layer position conversion, an error occurs in determining the layer movement state of the observer.

Fig. 2 (b) is a graph obtained by converting the altitude information of Fig. 2 (a) into the layer position. As the altitude information shown in FIG. 2 (a) changes in the range of -5? Alt? 5, the interlayer movement state within the range of one to three layers should be reflected and displayed in FIG. 2 (b). However, as altitude error is generated as in (210) in FIG. 2 (a), the layer-to-layer movement state is not fully reflected in FIG. 2 (b) It can be mistakenly detected that the movement has occurred.

Therefore, in order to minimize the error due to the initial bias of the pressure sensor or the altitude error due to the temperature / atmospheric pressure, it is necessary to continuously correct the altitude error due to the interlayer movement while tracking the layer moving state of the observer .

3 is a flow chart showing an interlayer movement detection method according to an embodiment.

The interlayer movement detecting device detects the layer moving state by using the altitude information measured through the pressure sensor as means for detecting the layer moving state in real time using a pressure sensor worn on one side of the body of the observer moving in a specific space The relative altitude error is continuously reflected in the process, thereby providing a method of increasing the accuracy of the determination of the interlayer movement of the observer.

In step 310, the collection unit of the interlayer movement detection apparatus may acquire at least one altitude information according to the position of the observer moving through the object space for a predetermined time period. The at least one altitude information includes an altitude value calculated corresponding to pressure information measured from a pressure sensor attached to one side of the observer. In step 310, the collecting unit may acquire the at least one altitude information whenever the movement of the observer occurs.

In step 320, the determination unit of the interlayer motion detection device can determine whether the object to be observed is moved between layers based on the altitude information change amount in the time interval. In step 320, the determination unit may calculate a change amount between the first altitude information at the start point of the time interval and the second altitude information at the end point of the time interval, and calculate, based on the calculation result, It is judged whether or not to move. In this case, the first altitude information can be understood as altitude information in which an altitude error with respect to a previous section of the time interval is reflected to an altitude value measured at a start point of the time interval.

In step 320, the determination unit may calculate a change amount between the first altitude information and the second altitude information using a window function method. For example, the determination unit calculates the amount of change by dividing a difference value between the first altitude information and the second altitude information by the number of altitude information collected during the time period.

The determination unit may compare the amount of change between the first altitude information and the second altitude information with a predetermined threshold in step 320 and if the change amount is equal to or greater than the threshold value, .

In step 330, if it is determined that the interlayer movement of the observer has occurred as a result of the determination in step 320 of the interlayer motion detection device, the altitude error with respect to the time interval may be updated. In step 330, the processing unit may further determine whether the observer is in a layer movement, and if the observer is determined to be in the layer movement, a difference value between the altitude information immediately before the layer movement occurs and the second altitude information So that the altitude error can be continuously updated.

FIG. 4 is a view for explaining a detailed process of tracked interlayer movement detection according to an embodiment.

In step 410, the altitude value measured at the position of the observer is input. The altitude value may be a value measured using a pressure sensor provided in the observer, and may be understood as an altitude value calculated corresponding to pressure information measured from the pressure sensor.

In step 420, the altitude information of the observer is calculated by reflecting the initial error to the input altitude value. In this case, the altitude information can be calculated as shown in Equation (1).

Figure 112016024062724-pat00001

In Equation (1), alt raw is the input altitude value, and err 0 means an initial error, which is input as 0 at the initial measurement.

In step 430, a change amount with respect to the altitude information in a specific section is calculated. At this time, the amount of change can be calculated using a window function method. For example, a difference value between the first altitude information measured at the start point of the specific section and the second altitude information measured at the end point of the specific section may be calculated, and the altitude information obtained during the specific section (N), which is calculated by the following equation (2). &Quot; (2) "

Figure 112016024062724-pat00002

Here, n is the window size, which means the number of altitude information collected in the interval.

In step 440, it is determined whether or not the layer to be observed of the observer moves based on the amount of change with respect to the altitude information. At this time, if the amount of change is larger than the predetermined threshold value, it is determined that the inter-layer movement of the observer has occurred. However, if the amount of change is smaller than the threshold value, it is determined that the inter-layer movement is not generated.

If it is determined in step 440 that the interlayer movement of the observer is generated, the layer movement state of the observer is detected in step 450, and it is additionally determined in step 460 whether the observer is in the layer movement. As a result of the determination in step 460, if it is determined that the observer is currently moving, the altitude error to be reflected in the specific section is recalculated. However, if it is determined that the current layer is not moving, the altitude error need not be recalculated and updated.

In step 470, the altitude error is recalculated corresponding to the determination result in step 460, which can be calculated as shown in equation (3).

Figure 112016024062724-pat00003

Here, alt 0 represents the altitude of the layer movement completion point or the initial starting point.

In step 480, the altitude error information in the specific section is updated using the altitude error calculated in step 470. As described above, the interlayer motion detection apparatus continuously utilizes the altitude information immediately before the layer movement as the altitude error value for the altitude information correction after the layer movement to continuously correct the altitude error according to the layer moving state of the to- The accuracy of the detection process can be enhanced.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. For example, it is to be understood that the techniques described may be performed in a different order than the described methods, and / or that components of the described systems, structures, devices, circuits, Lt; / RTI > or equivalents, even if it is replaced or replaced.

Therefore, other implementations, other embodiments, and equivalents to the claims are also within the scope of the following claims.

Claims (15)

A collecting unit for acquiring at least one altitude information according to a position of an observer moving in a target space for a predetermined time period;
Calculating an amount of change between the first altitude information at the start point of the time interval and the second altitude information at the end point of the time interval and determining whether the to-be- ; And
If it is determined that the inter-story movement has occurred, the processing unit updates the altitude error with respect to the time interval
Lt; / RTI >
Wherein the first altitude information is altitude information in which an altitude error with respect to a previous section of the time interval is reflected to an altitude value measured at the start point,
Wherein the processing unit further determines whether or not the observer is in the layer movement and continuously updates the altitude error using the difference between the altitude information immediately before the layer movement occurs and the second altitude information, . The method according to claim 1,
Wherein the altitude information comprises:
And an altitude value calculated corresponding to pressure information measured from a pressure sensor attached to one side of the observer. The method according to claim 1,
Wherein,
And acquires the at least one altitude information every time the movement of the observer occurs. delete The method according to claim 1,
Wherein,
And calculates the amount of change by dividing a difference value between the first altitude information and the second altitude information by the number of altitude information collected during the time interval. The method according to claim 1,
Wherein,
When the amount of change between the first altitude information and the second altitude information is equal to or greater than a predetermined threshold, it is determined that the interlayer movement of the observer has occurred. delete Obtaining at least one altitude information according to a position of an observer moving in a target space for a predetermined time period;
Calculating an amount of change between the first altitude information at the start point of the time interval and the second altitude information at the end point of the time interval and determining whether the object to be observed is moved between layers based on the calculation result; And
If it is determined that inter-story movement has occurred as a result of the determination, updating the altitude error for the time interval
Lt; / RTI >
Wherein the first altitude information is altitude information in which an altitude error with respect to a previous section of the time interval is reflected to an altitude value measured at the start point,
Wherein the step of updating the altitude error with respect to the time interval further includes determining whether the observer is in the course of layer movement and using the difference between the altitude information immediately before the occurrence of the layer movement and the second altitude information, The interlayer movement detection method comprising: 9. The method of claim 8,
Wherein the altitude information comprises:
And an altitude value calculated corresponding to pressure information measured from a pressure sensor attached to one side of the observer. 9. The method of claim 8,
Wherein the obtaining of the at least one altitude information comprises:
And acquiring the at least one altitude information every time the movement of the observer occurs. delete 9. The method of claim 8,
Wherein the step of determining whether the interlayer movement is performed includes:
And calculating the amount of change by dividing a difference value between the first altitude information and the second altitude information by the number of altitude information collected during the time interval. 9. The method of claim 8,
Wherein the step of determining whether the interlayer movement is performed includes:
And when the amount of change between the first altitude information and the second altitude information is equal to or greater than a predetermined threshold value, it is determined that the interlayer movement of the observer has occurred. delete A computer-readable recording medium embodying a program for performing an interlayer movement detection method according to any one of claims 8 to 10, 12, and 13.
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Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013200156A (en) * 2012-03-23 2013-10-03 Seiko Epson Corp Altitude measuring device, navigation system, program, and recording medium

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013200156A (en) * 2012-03-23 2013-10-03 Seiko Epson Corp Altitude measuring device, navigation system, program, and recording medium

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