JP5905750B2 - Remote monitoring device - Google Patents

Description

  The present invention relates to a remote monitoring device that performs wireless communication between a parent device possessed by a user and a child device attached to or possessed by the user's monitoring target, and notifies when it is determined that the parent device is separated from the child device. About.

2. Description of the Related Art Conventionally, there are known devices for preventing misplacement or removal of a bag containing important items, or preventing a child from getting lost or taken away.
In such a device, a child device is attached or possessed to a monitoring target such as a bag or a child, and the parent device for monitoring the child device is owned by a user such as a bag owner or a guardian of the child. It is determined that the two devices are separated based on the strength of the signal received when wireless communication is performed with the slave unit, and notification is made to the user, the monitoring center, or the like.

For example, in Patent Document 1, an oscillator (slave unit) that oscillates radio waves is placed in a bag or other belongings, and a receiver (master unit) that receives radio waves from the oscillators is stored in the chest of the owner of the belongings. It is disclosed to detect that the personal belongings are separated from the owner by using the oscillator and the receiver in a pocket or the like.
Specifically, the receiver issues an alarm when the intensity of radio waves oscillated by the oscillator falls below a certain level, and notifies the owner of misplacement.

Further, Patent Document 2 discloses an accessory slave unit (slave unit) that transmits radio waves, and a mobile phone radio unit that measures the electric field strength of radio waves transmitted from the accessory slave units at regular intervals and stores it in a memory ( It is disclosed to detect that both devices are separated from each other.
Specifically, the mobile phone radio compares the previously measured field strength with the current measured field strength, and determines that there is an abnormality when a decrease in the field strength exceeding a predetermined value is detected several times. To do.

Japanese Utility Model Publication No. 47-4873 Japanese Patent Laid-Open No. 10-327461

However, techniques such as Patent Document 1 and Patent Document 2 have the following problems.
Even if the distance between the parent device and the child device is the same, the average received signal strength may differ depending on the location where these devices are used. For example, indoors and outdoors have an environment where there are more walls that reflect signals in the indoors, and therefore, the average received signal strength tends to be higher than in the outdoors.
In this case, in the technique of Patent Document 1, since the separation is determined by comparing the received signal intensity with a uniform threshold value, the distance for determining the separation varies depending on the use location of the apparatus.

  Here, if the technique of Patent Literature 2 is used, the determination is made based on the difference between the reception signal strength measured last time and the reception signal strength measured this time, so that the problem in the technology of Patent Literature 1 can be avoided.

However, the received signal strength may frequently increase and decrease due to environmental changes around the user. For example, when the user is moving, if the distance from a person or a wall approaches or moves away, the received signal strength frequently increases or decreases accordingly. In addition, when the device monitors a bag, the user changes the positional relationship between the parent device and the child device, and the received signal strength increases or decreases accordingly. .
In this situation, when the technique of Patent Document 2 is used, if the decrease in the received signal strength accumulates little by little even though the received signal strength has not greatly decreased in the long term, the distance is increased. Although it is not, it is misjudged as separation.

  Thus, since the received signal strength depends on the place of use and the environmental change around the user, it is difficult to accurately determine the separation based only on the received signal strength.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a distance monitoring device capable of determining a distance that is not influenced by the place of use or environmental changes around the user.

  In order to achieve the above object, the remote monitoring device according to the present invention performs wireless communication between a parent device possessed by a user and a child device attached to or possessed by the user's monitoring target, and receiving in the wireless communication. In the remote monitoring device that performs notification when the determination means determines that the master unit and the slave unit are separated from each other by comparing a reception level indicating a signal strength with a predetermined determination criterion, the master unit and the slave unit A state detection unit that determines a movement state of the master unit from an output of the sensor of the master unit and a sensor for detecting a motion provided in each unit, and determines a motion state of the slave unit from an output of the sensor of the slave unit A combination determination unit that determines a combination of the movement state of the parent device and the movement state of the child device, and a reference setting unit that sets the predetermined determination criterion based on the combination. .

According to such a configuration, the separation monitoring device acts to determine each movement state from the movements of the main unit and the child unit, and to set a determination criterion for determining the separation based on a combination of the movement states of both units. To do.
As a result, when determining the separation based on the reception level, it is possible to make a determination in consideration of the movement state of the master unit and the slave unit, even if the reception level is affected by changes in the environment around the place of use or the user. Thus, it is possible to determine the separation that is not affected by this.

  In the separation monitoring apparatus of the present invention, the determination unit determines the separation using a first determination criterion as the predetermined determination criterion, and the state determination unit determines whether the parent device is stationary or a person. And whether the slave unit is stationary or carried by a person, and the combination determination unit is configured to select one of an exercise state of the master unit and an exercise state of the slave unit. It is determined whether one is stationary and the other is a carrying combination. When the combination is determined, the reference setting unit determines that the predetermined determination criterion is the separation from the first determination criterion. It is set to the second criterion that is easy to do.

According to such a configuration, the separation monitoring device is in a normal state when one of the movement state of the parent device and the movement state of the child device is stationary and the other is being carried. It acts to set a judgment standard that is easier to judge as a separation than the judgment standard.
If one of the parent device and the child device is stationary and the other is carried, it is assumed that the distance between the monitoring target and the user is separated due to an artificial factor. For example, there is a high possibility of theft that the monitoring target is carried by a third party while the user remains in a certain place, or the user is A situation where there is a high possibility of misplacement of being away from the monitoring target is assumed.
Therefore, when the separation monitoring device operates as described above, it is possible to quickly determine the separation in a situation where there is a high possibility that misplacement, removal, or child removal has occurred.

  In the separation monitoring apparatus of the present invention, the determination unit determines the separation using a first determination criterion as the predetermined determination criterion, and the state determination unit is configured so that the parent device is carried by a person. And the combination determination means determines whether the movement state of the parent device and the movement state of the child device are both portable combinations. When the combination is determined, the reference setting unit sets the predetermined determination reference to a third determination reference that is less likely to be determined as the separation than the first determination reference.

According to such a configuration, the distance monitoring device has a determination criterion that is less likely to be determined to be a separation than a normal determination criterion when the movement state of the parent device and the movement state of the child device are both carried. Acts to set.
The fact that both the base unit and the slave unit are carried means that when the monitoring target is a bag, the user is carrying a bag or when the monitoring target is a child, A situation is assumed in which the user and the child are respectively carried, that is, a situation in which the user and the child are assumed to move together.
Therefore, since the distance monitoring device acts as described above, it becomes difficult to determine that the distance is used in situations where it is unlikely that the device is misplaced or taken away, or the child is lost or taken away. Even if the reception level is affected by the environmental change around the user, it is possible to prevent erroneous determination of separation.

  Further, in the separation monitoring device of the present invention, the combination determination unit determines whether the movement state of the parent device and the movement state of the child device are both stationary combinations, and the reference setting unit determines whether the combination is When the determination is made, the predetermined determination criterion is set to a fourth determination criterion that is more difficult to determine the separation than the third determination criterion.

The fact that both the parent machine and the child machine are stationary means that the monitored object can be separated from the user, such as when the monitored object is placed on the floor and the owner of the luggage is sitting nearby. Is assumed to be low. Therefore, in such a situation, the separation monitoring device acts to set a determination criterion that is more difficult to determine the separation than the determination criterion that is set when both the parent device and the child device are being carried.
Thereby, even if the reception level is affected by the environment of use or the environment around the user, it can be better prevented from being erroneously determined as being separated.

  According to the present invention, even if the reception level is affected by changes in the environment of use or the surroundings of the user, it is possible to determine a distance that does not depend on the reception level.

It is a block diagram which shows the structure of the separation monitoring apparatus which concerns on this invention. It is a figure which shows the time change of the acceleration in the "carrying" state which the separation monitoring apparatus which concerns on this invention determines. It is a figure which shows the criteria table information which the memory | storage means (master | base_unit) of the separation monitoring apparatus which concerns on this invention memorize | stores. It is a flowchart (1) which shows operation | movement of the control part (master) of the separation monitoring apparatus which concerns on this invention. It is a flowchart (2) which shows operation | movement of the control part (master | base_unit) of the separation monitoring apparatus which concerns on this invention. It is a flowchart (1) which shows operation | movement of the state determination means (a main | base station and a subunit | mobile_unit) of the separation monitoring apparatus which concerns on this invention. It is a flowchart (2) which shows operation | movement of the state determination means (a main | base station and a subunit | mobile_unit) of the separation monitoring apparatus which concerns on this invention.

Embodiments of the present invention will be specifically described below with reference to the drawings.
FIG. 1 is a block diagram showing a configuration of a separation monitoring apparatus according to the present invention.
The remote monitoring device 1 includes a child device 3 attached to or possessed by a monitored object such as a bag or a child, and a parent device 2 possessed by a user such as a bag owner or a guardian of the child in order to monitor the monitored object. It consists of.
For example, base unit 2 is placed in the user's breast pocket. When the handset 3 is attached to the bag, the handset 3 is attached to the handle portion of the bag so as not to be easily removed by an attachment means (not shown) such as a wire provided in the handset 3. Is done.

The remote monitoring device 1 performs wireless communication between the parent device 2 and the child device 3, detects the strength (reception level) of the received signal in the wireless communication, compares the received level with a predetermined criterion, It is determined that the machine 2 and the child machine 3 are separated from each other, and notifies the user, the monitoring center, or the like.
In particular, in the present invention, the movement state of the parent device 2 and the child device 3 is detected by a sensor that detects movement, and is actually taken away or misplaced from the combination of the movement state of the parent device 2 and the movement state of the child device 3. It is determined whether or not such an action is occurring, and a predetermined determination criterion is set according to the determination result.

In the present invention, the separation means that the user (master unit 2) and the monitoring target (slave unit 3) are separated to an abnormal interval that is not considered a normal interval.
Here, the normal interval between the user and the monitoring target is assumed when, for example, the monitoring target is an item such as a bag, and the user is holding or placing the item on the side. If the monitoring target is a person such as a child, it is assumed that the user can monitor the person and protect the person from danger It is the interval between the user and the person. In the present invention, in consideration of the normal interval described above, such an abnormal interval that is not a normal interval is determined as a separation using the reception level in the wireless communication between the parent device 2 and the child device 3. It is.

<Master unit>
The base unit 2 mainly includes an acceleration sensor 22 that detects acceleration as a sensor that detects motion, a communication unit 21 that performs wireless communication with the handset 3, a storage unit 26 including a memory, and a carry counter 23. The user is informed of the distance between the determination counter 24, the continuation counter 25 for determining that the value of the determination counter 24 is unchanged, and the slave unit 3 by sound or light. And a control unit 20 that is configured by an MPU, a microcomputer, and the like and that controls each unit.

  The acceleration sensor 22 is a three-axis acceleration sensor that measures acceleration in three directions, and outputs the measured acceleration signal of each axis to the control unit 20.

  The communication unit 21 includes an antenna and is a unit that transmits and receives a radio signal to and from the child device 3, transmits a request signal for requesting predetermined information to the child device 3, and transmits the request signal from the child device 3 in response to the request signal. It is means for executing a communication process for receiving the received information every predetermined time (for example, every 1 second).

  Specifically, the communication means 21 receives a request signal for requesting information on received signal strength indication (RSSI) indicating the strength of the signal when receiving the signal and information on the motion state of the slave unit 3. Transmit to machine 3. Upon receiving this request signal, handset 3 detects the received signal strength when this signal is received, and returns the detected received signal strength information and the motion state information detected by itself to base unit 2. To do.

The communication means 21 is set with its own identification code and the identification code of the slave unit 3 as a communication partner in advance. And when the communication means 21 transmits a request signal to the subunit | mobile_unit 3, the request signal is made to include the identification code of an own as a transmission origin, and the identification code of the subunit | mobile_unit 3 made into a communicating party as a transmission destination. Perform transmission processing.
When the communication unit 21 receives a signal including its own identification code from the slave unit 3, the communication unit 21 performs signal recognition processing as a signal addressed to itself.

The communication unit 21 includes a signal strength detection unit 211 that detects a received signal strength when receiving a reply from the slave unit 3.
Then, the communication means 21 outputs to the control unit 20 the received signal strength and exercise state information received from the slave unit 3 and the received signal strength detected by itself (the master unit 2) obtained by the communication process described above. To do.

  The storage means 26 stores a detected reception level, a predetermined determination criterion for determining the separation, an information history of the own exercise state, and the like. Details and use of information stored in the storage unit 26 will be described later.

  The control unit 20 includes a microcomputer including a CPU, a ROM, a RAM, and the like and peripheral circuits thereof, and controls each unit of the parent device 2 described above. The control unit 20 includes, as a functional module realized by the microcomputer and a computer program executed on the microcomputer, a reception level detection unit 201, a determination unit 206, a monitoring unit 205, an abnormality determination unit 207, and a state determination unit. 202, a combination determination unit 203, a reference setting unit 204, and an abnormality processing unit 208.

  The reception level detection unit 201 uses any one of the reception signal strength of the slave unit 3 and the reception signal strength of the base unit 2 output from the communication unit 21 as a reception level indicating the strength of the reception signal in the communication processing described above. Select and store in the storage means 26.

Specifically, the reception level detection unit 201 refers to the reception level in the previous communication process stored in the storage unit 26, and determines the received signal strength of the slave unit 3 and the own received signal strength in the current communication process. Among them, the reception signal strength closer to the previous reception level is selected and stored as the current reception level.
Thus, by adopting the reception signal strength close to the previous reception level as the reception level, even if the reception signal strength frequently increases or decreases due to environmental fluctuations around the user, the influence of this increase and decrease can be mitigated. .

  If the previous reception level is not stored in the storage means 26 immediately after the power is turned on, the reception level may be appropriately determined by the following method. For example, the received signal strength of the slave unit 3 in the current communication process in which the received radio wave intensity when the master unit 2 and the slave unit 3 are sufficiently close is stored in advance as an initial value, There are methods such as setting the average value of the strength and own received signal strength as the reception level, and setting the reception radio wave strength of the base unit 2 as the reception level.

The monitoring unit 205 is a unit for monitoring the tendency of fluctuations in the reception level.
When the reception level is detected by the reception level detection unit 201, the monitoring unit 205 compares the reception level detected this time with the reception level detected last time stored in the storage unit 26. Then, if there is a decrease in reception level that is greater than or equal to a predetermined value between the previous reception level and the current reception level, a predetermined value (for example, 1) is added to the determination counter 24. On the other hand, if there is a predetermined reception level increase from the previous reception level to the current reception level, a predetermined value (for example, 1) is subtracted from the determination counter 24.
Specifically, the monitoring unit 205 subtracts the previous reception level from the current reception level, and adds a predetermined value to the determination counter 24 when determining that the subtraction value is equal to or less than the threshold value T1. If it is determined that the subtraction value is equal to or greater than T2, a predetermined value is subtracted from the determination counter 24.
Note that when the value of the determination counter 24 is 0, the monitoring unit 205 does not subtract the determination counter 24 even if the reception level increases more than a predetermined level between the current time and the previous time.

  As the monitoring unit 205 increases or decreases the determination counter 24 in this way, the determination counter 24 is often added when the reception level tends to decrease. For this reason, the higher the value of the determination counter 24, the stronger the tendency of the reception level to decrease.

  It should be noted that T1 and T2 that serve as a reference for increasing or decreasing the determination counter 24 can be obtained experimentally. Specifically, the received signal strength changes when the base unit 2 and the handset 3 are actually separated from each other, and the positional relationship changes without changing the distance between the base unit 2 and the handset 3 near the user. Compared with fluctuations in received signal strength when only The determination counter 24 does not change or is subtracted when there is a strong tendency to be added to the determination counter 24 when it is actually separated, and only the positional relationship changes near the user. T1 and T2 (T1 <T2) where the tendency is strong may be obtained experimentally.

  In addition, the predetermined value to be added to the determination counter 24 and the predetermined value to be subtracted from the determination counter 24 are both 1 in the above-described example. However, if it is easy to determine the separation, the predetermined value to be added> subtraction In order to make it difficult to determine the separation, the predetermined value to be added <the predetermined value to be subtracted.

The abnormality determination means 207 is a means for determining that the parent device 2 and the child device 3 are separated from each other using the value of the determination counter 24 and the reception level. The abnormality determination unit 207 determines that the parent device 2 and the child device 3 are separated when all of the determination conditions (1) to (3) below satisfy the determination conditions specified in the reference setting unit 204 described later.
(1) Determination counter 24 value ≧ predetermined number of times (predetermined number of times ≧ 2)
(2) Current reception level value ≦ Reception level value at the start of the latest determination counter 24 addition−predetermined value (T3)
(3) Determination counter 24 value ≧ previous determination counter 24 value + 1
Here, the determination condition (1) means that the reception level tends to decrease, as can be seen from the description of the monitoring means 205 described above.

Specific determination processing of the determination condition (2) is performed as follows. First, the monitoring unit 205 overwrites and stores the reception level in the immediately preceding communication process when the value of the determination counter 24 is changed from 0 to 1 in the storage unit 26 as the reception level value at the start of the determination counter 24 addition. To. Then, the abnormality determination unit 207 reads this reception level with reference to the storage unit 26, and determines whether or not the current reception level is equal to or less than a value obtained by subtracting a predetermined value (T3) from the read reception level.
As a result, the abnormality determination unit 207 determines whether the reception level has decreased to a certain distance from the reception level when the tendency that the reception level starts to decrease to the present time. . Note that T3 is experimentally determined in consideration of a distance (for example, 5 m) to be determined as a separation.

The specific determination processing of the determination condition (3) above is to read the value of the previous determination counter 24 from the storage means 26, and the value of the current counter 24 is equal to or greater than the value obtained by adding 1 to the value of the previous counter 24. It is determined whether or not. The abnormality determination means 207 determines that the determination condition (3) is satisfied when this determination is affirmed.
The determination condition (1) is not satisfied until the determination counter 24 reaches the predetermined number of times set to 2 or more, whereas the determination condition (3) does not satisfy the predetermined number of times. However, if the current value of the determination counter 24 is a value obtained by adding 1 to the previous value of the determination counter 24, the condition is satisfied. For this reason, it can be said that the determination condition (3) is a determination criterion that makes it easier to determine the separation than the determination condition (1).

  Furthermore, after determining that the master unit 2 and the slave unit 3 are separated from each other, the abnormality determination unit 207 is in a state in which the master unit 2 and the slave unit 3 approach each other and approach from the separated state when the reception level becomes a predetermined value or more. It is determined that it has recovered. When this restoration is determined, the monitoring unit 205 clears the determination counter 24 to zero.

  The state determination unit 202 samples the acceleration signal of each axis of the acceleration sensor 22 a plurality of times (for example, 30 times) during a predetermined sampling period (for example, 2 seconds), and the sampling value (x, Based on y, z), the movement state of base unit 2 is determined. The state determination means 202 includes a “carrying” state indicating that the parent device 2 is being carried by a person, a “stationary” state in which the parent device 2 is neither moving nor rotating, Three types of motion states of “other motion” states indicating states that are not “still” are determined.

The state determination unit 202 determines the “carrying” state as follows. Since the “carrying” state is a state in which the parent device 2 is carried by a person, the acceleration sensor 22 detects an acceleration that occurs when the person is walking or running. Here, the time-dependent change in acceleration when a person is walking or running, with the horizontal axis as the time axis and the vertical axis as the acceleration,
As shown in FIG. 2, it is known that the waveform approximates to a regular waveform that repeats up and down movement at a predetermined cycle around the value of gravitational acceleration 1G (= 9.8 m / s ² ).

  Therefore, the state determination unit 202 first detects the sampling values (x, y, z), a triaxial composite value is calculated, time series data of the triaxial composite value is obtained, and this time series data is smoothed and used as determination data for determining the “carrying” state. For the smoothing process, for example, a known method such as taking a weighted moving average of the latest five three-axis composite values may be adopted as appropriate.

Then, the state determination unit 202 determines whether or not determination data within the sampling period includes determination data exceeding the reference acceleration (hereinafter referred to as “upward determination data”). Specifically, the state determination unit 202 includes a reference acceleration A and a reference acceleration B set so as to sandwich the gravitational acceleration 1G (reference acceleration A <1G <reference acceleration B, for example, reference acceleration A = 0.95G, By using the reference acceleration B = 1.05G (see FIG. 2), after the reference acceleration A is exceeded, it is determined whether there is determination data that exceeds the reference acceleration B without exceeding the reference acceleration A. It is determined whether there is data for determining the upper limit. Then, when there is data for determination of excess, it is determined whether or not both of the following two conditions are satisfied.
(A) Overtime <predetermined threshold (threshold is, for example, 0.4 seconds)
(A) Elapsed time from the most recent past increase time is within a predetermined range (the predetermined range is, for example, between 0.4 seconds and 1.3 seconds)
In addition, when there are a plurality of pieces of upper determination data within the sampling period, it is determined whether each of the above conditions (a) and (b) is satisfied for each upper determination data.

In the above condition (a), the excess time is the time from when the determination data exceeds the reference acceleration A to when the determination data exceeds the reference acceleration B (see FIG. 2).
Further, the condition (a) above exceeds the reference acceleration B in the upper determination data to be determined from the time when the reference acceleration B has been exceeded in the latest upper determination data of the upper determination data to be determined. This is true when the elapsed time up to the point in time (see FIG. 2) is within a predetermined range. Note that if there is no latest past determination data in the sampling period, the elapsed time is calculated with reference to the previous determination data.

  The state determination means 202 adds 1 to the carry counter 23 for determining the “carrying” state every time it is determined that both the conditions (a) and (b) are satisfied for the overrun determination data. Go.

Furthermore, the state determination unit 202 determines whether there is determination data that falls below the reference acceleration (hereinafter, referred to as lower determination data) in the determination data within the sampling period. Specifically, the state determination unit 202 determines whether or not there is determination data that does not exceed the reference acceleration B and then falls below the reference acceleration A after being below the reference acceleration B. Determine if there is any. Then, when there is data for lowering determination, it is determined whether or not both of the following two conditions are satisfied.
(C) Lower time <predetermined threshold (threshold is, for example, 0.4 seconds)
(D) Elapsed time from the last lower point in the past is within a predetermined range (the predetermined range is, for example, between 0.4 seconds and 1.3 seconds)
If there are a plurality of lower judgment data within the sampling period, it is determined whether the conditions (c) and (d) are satisfied for each lower judgment data.

In the above condition (c), the lowering time is the time from when the determination data falls below the reference acceleration B to when it falls below the reference acceleration A.
In addition, the above condition (d) is such that the reference acceleration A is lower than the reference acceleration A in the lower determination data to be determined from the time when the lower acceleration determination data in the latest past lower determination data of the determination target is lower than the reference acceleration A. This is true if the elapsed time up to the point in time is within a predetermined range. Note that if there is no latest past lower determination data within the sampling period, the elapsed time is calculated with reference to the previous lower period determination data.

  The state determination means 202 adds 1 to the carry counter 23 for determining the “carrying” state every time it is determined that both the conditions (c) and (d) are satisfied for the lowering determination data. Go.

  As described above, the state determination unit 202 counts the upper determination data and the lower determination data satisfying the predetermined condition by the carry counter 23, and this count value is a predetermined value (for example, 4). When it becomes above, it determines with a "carrying" state and memorize | stores the said state in the memory | storage means 24. FIG.

The predetermined threshold value and the predetermined range in the conditions (a) to (d) and the predetermined value to be compared with the count value of the carry counter 23 are measured by measuring waveform data when a person walks or runs, and the waveform data Can be determined experimentally.
Further, the above-described processing is intended to detect periodicity appearing in waveform data during walking or running of a person by a simple method, but is not limited to this method, and is a known method such as frequency analysis or zero crossing. The result of the law may be used.

  Next, the determination process of the “still” state of the state determination unit 202 will be described. The state determination unit 202 performs a process for determining whether or not there is a change in acceleration and a process for determining whether or not there is a rotation in order to determine that the state in which the base unit 2 is neither moving nor rotating is a “still” state. If there is no change and no rotation, it is determined that the state is “still”.

  In order to determine the presence / absence of rotation, the state determination unit 202 first calculates an average of output values for each axis in the first half and the second half of the sampling period. For example, assuming that 30 sampling values are acquired for each axis during a sampling period of 2 seconds, the average value of 15 sampling values in the first half of the second period and the average value of 15 sampling values in the second half of the second period Is calculated for each axis. In addition, when each axis is the X axis, the Y axis, and the Z axis, the average value of the first half of each axis is X (front), Y (front), and Z (front), respectively, and the average of the second half of each axis The values are X (rear), Y (rear), and Z (rear), respectively.

And the state determination means 202 takes the difference about the average value of the first half for every combination of two different axes. Specifically, the following calculation is performed.
・ Combination of X axis and Y axis: X (front)-Y (front)
・ Combination of Y axis and Z axis: Y (front)-Z (front)
・ Combination of Z axis and X axis: Z (front)-X (front)
In addition, about these calculation results, it is set as [XY] (front), [YZ] (front), and [ZX] (front), respectively.

Next, the state determination unit 202 calculates a difference for the average value in the latter half for each combination of two different axes. Specifically, the following calculation is performed.
・ Combination of X axis and Y axis: X (rear)-Y (rear)
・ Combination of Y axis and Z axis: Y (rear)-Z (rear)
・ Combination of Z axis and X axis: Z (rear)-X (rear)
In addition, about these calculation results, it is set as [XY] (rear), [YZ] (rear), and [ZX] (rear), respectively.

Further, the state determination unit 202 calculates the absolute value by taking the difference between the difference value calculated in the first half and the difference value calculated in the second half for each combination of two different axes. Specifically, the following calculation is performed.
・ Combination of X axis and Y axis: | [XY] (front)-[XY] (rear) |
・ Combination of Y and Z axes: | [YZ] (front)-[YZ] (rear) |
・ About the combination of Z axis and X axis: | [ZX] (front)-[ZX] (rear) |
Then, the state determination unit 202 determines whether or not all of these three calculated values are equal to or less than a predetermined value (for example, 0.1 G) that is a value substantially close to zero.

Here, the fact that all three calculated values are less than or equal to the predetermined value means that in all combinations of two different axes, the amount of acceleration difference between the axes hardly changed between the first half and the second half of the sampling period. Indicates that the machine 2 is not rotating.
For this reason, the state determination means 202 acts to determine that it is not rotating by determining that the condition that the above three calculated values are all equal to or less than the predetermined value is satisfied.

Further, in addition to the establishment of this condition, the state determination unit 202 determines the “still” state on condition that there is no change in the variance value of acceleration. Specifically, the state determination unit 202 calculates a composite value (three-axis composite value) of the sampling values (x, y, z) of each axis obtained each time during the sampling period by the following formula, Three triaxial composite values are obtained.
Triaxial composite value = √ (x ² + y ² + z ² )
Next, a variance value of the plurality of three-axis composite values is calculated, and it is determined whether the variance value is equal to or less than a threshold value. Here, when the variance value is equal to or smaller than the threshold value, the motion state of the parent device 2 is determined to be a “still” state in which the acceleration applied to the parent device 2 has not changed.

  The threshold value to be compared with the variance value can be obtained experimentally. For example, a variance value calculated between a state where the person is sitting on a chair with the parent device 2 and a state where the person is moving may be examined, and a threshold value for separating these states may be set as appropriate.

  If the state determination unit 202 determines that it is neither the “carrying” state nor the “still” state by the above-described determination process, it determines that the state is the “other movement” state.

The combination determination unit 203 is a unit that determines a combination of the movement state of the parent device 2 determined by the state determination unit 202 and the movement state of the child device 3 received from the child device 3.
Specifically, the combination determination unit 203 determines whether one of the movement state of the parent device 2 and the movement state of the child device 3 is a “stationary” state and the other is a “carried” state combination. Whether the movement state of 2 and the movement state of the slave unit 3 are a combination of the “carrying” state, and whether the movement state of the parent unit 2 and the movement state of the slave unit 3 are both a combination of the “stationary” state To do.

The reference setting unit 204 sets one of the determination criteria (1) to (3) for determining the above-described separation according to the combination of the exercise states determined by the combination determination unit 203.
Furthermore, when setting the criterion (1), the criterion setting unit 204 sets the predetermined number corresponding to the combination of the exercise state with reference to the criterion table information regarding the predetermined number of times in the criterion (1). To do.

Here, the determination criterion table information will be described with reference to FIG. The determination criterion table information is information stored in advance in the storage unit 26, and determines a predetermined number of times in the determination condition (1) for each of the exercise state of the parent device 2 and the exercise state of the child device 3. In the illustrated example, when the combination of the movement state of the parent device 2 and the movement state of the child device 3 is “carried”, the predetermined number of times is b. When the combination of the motion state of the master unit 2 and the motion state of the slave unit 3 is “still”, the predetermined number of times is c. When the combination of the movement state of the parent device 2 and the movement state of the child device 3 is another combination, the predetermined number of times is a.

The values of the predetermined times a, b, and c are appropriately set within a range of 2 ≦ a <b <c. The larger the predetermined number of times in the determination condition (1), the more difficult the condition is satisfied. Therefore, when the predetermined number of times is set to c, it is less likely to be determined as being separated than when the predetermined number of times is set to a or b. This means that it is more difficult to determine the separation than when the predetermined number of times is a.
In addition, when any one of the movement state of the main unit 2 and the movement state of the child unit 3 is a “stationary” state and the other is a “carrying” state, the determination is made without using the determination condition (1). Since the separation is determined using the condition (3), “determination condition (3)” is described in parentheses in FIG.

The specific setting operation of the determination criterion by the reference setting unit 204 will be described. A combination of the movement state of the parent device 2 and the movement state of the child device 3 in the “stationary” state and the other in the “carrying” state. If it is, the determination condition (3) is set.
When the movement state of the base unit 2 and the movement state of the handset 3 are both “carried”, the determination criteria (1) and the determination criterion (2) are set and the predetermined number of times in the determination criterion (1) is set. Set to b.
When the movement state of the parent device 2 and the movement state of the child device 3 are both “stationary”, the determination criteria (1) and the determination criterion (2) are set and the predetermined number of times in the determination criterion (1) is c Set to.
When the movement state of the parent device 2 and the movement state of the child device 3 are other combinations, the determination criterion (1) and the determination criterion (2) are set, and the predetermined number of times in the determination criterion (1) is set to a.

When the abnormality determination unit 207 determines that the parent device 2 and the child device 3 are separated from each other, the abnormality processing unit 208 operates the notification unit 27 to notify the user that there is a separation. Run.
Further, the abnormality processing unit 208 stops the operation of the notification unit 27 when the abnormality determination unit 207 determines that the separated state has been restored.
Note that the abnormality processing by the abnormality processing unit 208 is not limited to the above-described processing. For example, a reporting unit for reporting to the monitoring center via a wireless communication line is further provided in the base unit 2, and this reporting unit is used. Notification may be performed by executing processing for reporting to the monitoring center.

<Slave unit>
The slave unit 3 mainly includes an acceleration sensor 32 that detects acceleration as a sensor for detecting motion, a communication unit 31 that performs wireless communication with the master unit 2, a storage unit 33 that includes a memory, an MPU, a microcomputer, and the like. And a control unit 30 configured to control each unit.

  The acceleration sensor 32 is a triaxial acceleration sensor that measures acceleration in three directions, and outputs the measured acceleration signal of each axis to the control unit 30.

The control unit 30 includes a microcomputer including a CPU, a ROM, a RAM, and the like and peripheral circuits thereof, and controls each unit of the slave unit 3 described above. The control unit 30 includes a state determination unit 301 as a functional module realized by the microcomputer and a computer program executed on the microcomputer.
The state determination unit 301 is a unit that determines the motion state of the child device 3 based on the acceleration signal from the acceleration sensor 32. Since the specific configuration is the same as that of the state determination unit 202 of the parent device, the description is omitted.

The communication unit 31 is a unit that transmits and receives a radio signal to and from the base unit 2.
When the communication means 31 stores its own identification code and receives a request signal including its own identification code from the parent device 2, information corresponding to this request signal is sent to the parent of the transmission source included in the request signal. This is a means for replying to the machine 2.

Similarly to the communication unit 21 of the base unit 2, the communication unit 31 includes a signal strength detection unit 311 that detects a received signal strength when a request signal from the base unit 2 is received.
When receiving the request signal from the base unit 2, the communication unit 31 detects the received signal strength when the signal is received by the signal strength detecting unit 311, and stores the detected received signal strength information in the storage unit 33. Information on the current freight state is transmitted to the base unit 2.

<Description of operation>
The operation of the separation monitoring device 1 configured as described above will be described with reference to the drawings.
4 and 5 are flowcharts showing the operation of a program that is repeatedly executed at predetermined time intervals (for example, every 1 second) by the control unit 20 of the parent device 2 while the parent device 2 is powered on. .

When starting the program, control unit 20 causes communication means 21 to transmit a request signal to handset 3 (ST01). The communication means 21 transmits a request signal with the identification code of the handset 3 set in advance as a transmission destination.
Then, after transmitting the request signal, the communication means 21 waits for a reply addressed to itself from the handset 3, and receives the received signal strength and exercise state information detected on the handset 3 side from the handset 3 ( ST02).
Further, the communication means 21 detects the received signal strength when the reply is received from the handset 3 by the signal strength detecting means 211 (ST03).
Then, the communication means 21 outputs the received reception signal strength and motion state information of the slave unit 3 and the detected reception signal strength of itself to the control unit 20.

When the series of communication processes by the communication unit 21 is completed, the control unit 20 detects the reception level by the reception level detection unit 201 and stores the detected reception level in the storage unit 26 (ST04).
Specifically, the reception level detection unit 201 reads the reception level in the previous communication process from the storage unit 26, and among the reception signal strength of the handset 3 input this time from the communication unit 21 and its own reception signal strength, The reception signal strength closer to the previous reception level is selected as the current reception level, and the selected reception signal strength is stored in the storage means 26.

Next, the control unit 20 causes the combination determination unit 203 to execute a process of determining a combination of the movement state of the parent device 2 determined by the state determination unit 202 and the movement state of the child device 3 received from the child device 3 ( ST05 to ST07), the reference setting unit 204 is caused to execute processing for setting a determination reference according to the determined combination (ST08 to ST11).
First, the combination determination unit 203 determines whether one of the movement state of the parent device 2 and the movement state of the child device 3 is a combination of the “stationary” state and the other is the “carried” state (ST05). .
If it is determined that one of them is a combination of the “stationary” state and the other is the “carrying” state (ST05-Yes), the reference setting unit 204 uses the determination condition (3 ) Is set (ST08).

When the combination determination unit 203 determines that one of the combinations is not in the “stationary” state and the other is in the “carrying” state (ST05-No), the movement state of the parent device 2 and the movement state of the child device 3 are both It is determined whether or not the combination is in the “carry” state (ST06).
If both are determined to be in the “carried” state combination (ST06-Yes), the reference setting unit 204 sets the determination condition (1) and the determination condition (2) as the determination criterion for determining the separation. The predetermined number of times in the determination condition (1) is set to b (ST09).

When the combination determination unit 203 determines that both are not in the “carried” state (ST06-No), it is determined whether or not the movement state of the parent device 2 and the movement state of the child device 3 are both the “stationary” state combination. Determine (ST07).
When it is determined that both are combinations of the “still” state (ST07-Yes), the reference setting unit 204 sets the determination condition (1) and the determination condition (2) as the determination criterion for determining the separation, The predetermined number of times in the determination condition (1) is set to c (ST10).

  If the combination determination unit 203 determines that both are not in the “still” combination (other combinations) (ST07-No), the reference setting unit 204 uses the determination condition (1) and the determination condition (1) as the determination conditions for determining the separation. Determination condition (2) is set, and a predetermined number of determination conditions (1) is set to a (ST11).

When the processing by the combination determining unit 203 and the reference setting unit 204 is completed, the control unit 20 executes processing for monitoring the reception level fluctuation tendency in the monitoring unit 205 (ST20 to ST24).
First, the monitoring unit 205 reads the previous reception level with reference to the storage unit 26. Then, the monitoring unit 205 subtracts the previous reception level read from the reception level detected this time (ST20).
Next, the monitoring unit 205 compares the subtraction value in ST20 with the threshold values (T1, T2) stored in the storage unit 26, and adds / subtracts the determination counter 24.
Specifically, when determining that the subtraction value is equal to or less than T1 (ST21-Yes), the monitoring unit 205 adds (for example, adds 1) to the determination counter 24 (ST22). When it is not determined in ST21 that the subtraction value is equal to or less than T1 (ST21-No), when the monitoring unit 205 determines that the subtraction value is equal to or greater than T2 (ST23-Yes), the determination counter 24 is subtracted (for example, 1). Subtract) (ST24).
When the subtraction value is neither T1 or less nor T2 or more, the monitoring unit 205 skips the addition or subtraction processing of the determination counter 24 (ST23-No). This process is a process for skipping the addition or subtraction process of the determination counter 24 when there is no significant change in the reception level between the previous time and the current time.

  When the process of the monitoring unit 205 is completed, the control unit 20 causes the abnormality determination unit 207 to execute a process of determining whether or not all of the determination criteria set by the reference determination unit 204 are satisfied (ST25). If the abnormality determination means 207 determines that the determination criterion is satisfied (ST25-Yes), it determines that the parent device 2 and the child device 3 are separated (ST26).

  When the abnormality determination unit 207 determines the separation (ST25-Yes), the control unit 20 causes the abnormality processing unit 208 to execute the abnormality process (ST27). And the control part 20 complete | finishes this program.

  When the determination in ST25 in the abnormality determination unit 207 is negative (ST25-No), the control unit 20 ends the program.

Although not shown in the flowcharts of FIGS. 4 and 5, the monitoring unit 205 of the control unit 20 is separately provided with the number of times ST23 is denied (that is, the number of times T1 <subtraction value <T2). When the value of the continuation counter 25 reaches a predetermined number of times (for example, 10 times) (that is, when the state where the determination counter 24 does not change continues for 10 seconds), the value of the determination counter 24 is The process of clearing (setting to 0) is performed.
As a result, when the state in which the reception level has not changed significantly between the previous time and the current time continues for a predetermined time, the determination counter 24 is once cleared, so that erroneous determination due to environmental changes around the user can be better prevented. .

Further, when the reception level detected this time is a value at which the parent device and the child device are sufficiently close (for example, a value corresponding to 1 m or less), the monitoring unit 205 clears the determination counter 24 (sets it to 0). . Specifically, after ST04, the monitoring unit 205 determines whether or not the reception level detected this time is equal to or higher than a threshold value (for example, a reception level corresponding to 1 m). Set to 0 to end the program. If this determination is negative, the process proceeds to ST05.
As a result, the counter is once cleared in a state where the parent device and the child device are sufficiently close to each other, so that it is possible to better prevent erroneous determination due to an environmental change around the user.

  Furthermore, in the process of ST02, when the communication means 21 does not accept a reply addressed to itself from the slave unit 3 for a predetermined time, it is detected as “communication impossible”, and the abnormality determination means 207 detects this “communication impossible”. Is detected as a separation when the detection continues for a predetermined time (for example, 6 seconds).

  Next, state determination processing executed by the state determination unit 202 of the parent device 2 and the state determination unit 301 of the child device 3 will be described with reference to FIGS. Both means (202, 301) operate in the same manner, and will be described together here.

The state determination means (202, 301) samples the acceleration signal of each axis output from the acceleration sensor (22, 32) a plurality of times (for example, 30 times) during a predetermined sampling period (for example, 2 seconds) (ST111). , ST112-No).
When the state determination means (202, 301) determines that the sampling period has ended (ST112-Yes), it calculates a three-axis composite value of the sampling values (x, y, z) of each axis obtained each time ( ST113). Then, the time-series data of the three-axis composite value is smoothed and the determination data is calculated (ST114).

Next, the state determination means (202, 301) determines whether or not there is an excess determination data in the determination data within the sampling period (ST115). If there is no data for determination of surplus (ST115-No), the process proceeds to ST120.
When there is data for determination of surplus (ST115-Yes), it is determined whether or not the surplus time is less than the threshold for the data for determination of surplus (ST116). When the overtime is less than the threshold (ST116-Yes), it is determined whether or not the elapsed time from the most recent past overtime is within a predetermined range (ST117). If it is determined that the elapsed time from the most recent past time point is within the predetermined range (ST117-Yes), 1 is added to the carry counter 23 (ST118), and the process proceeds to ST119.
On the other hand, if the excess time is not less than the threshold for the excess determination data (ST116-No), or if the elapsed time from the most recent past increase time is not within the predetermined range (ST117-No), the process proceeds to ST119.
In ST119, the state determination means (202, 301) determines whether or not the processing from ST116 to ST118 has been performed for all of the upward determination data determined in ST115. When all the processes are not performed (ST119-No), the processes from ST116 to ST118 are performed in the same manner with respect to the upper determination data that is not processed.
When all the processes have been performed (ST119-Yes), the process proceeds to ST120.

In ST120, the state determination means (202, 301) determines whether there is under-determination data in the determination data within the sampling period (ST120). When there is no lower determination data (ST120-No), the process proceeds to ST125.
If there is data for lowering determination (ST120-Yes), it is determined whether or not the lowering time is less than the threshold for the lowering determination data (ST121). When the lowering time is less than the threshold value (ST121-Yes), it is determined whether or not the elapsed time from the latest lowering point in the past is within a predetermined range (ST122). When it is determined that the elapsed time from the latest past time point is within the predetermined range (ST122-Yes), 1 is added to the carry counter 23 (ST123), and the process proceeds to ST124.
On the other hand, if the lower time is not less than the threshold for the lower determination data (ST121-No), or if the elapsed time since the last lower time is not within the predetermined range (ST122-No), the process proceeds to ST124.
In ST124, the state determination means (202, 301) determines whether or not the processing from ST121 to ST123 has been performed for all the data for lowering determination determined in ST120. If all the processes have not been performed (ST124-No), the processes from ST121 to S123 are performed in the same manner for the data for determining the excess that has not been processed.
When all the processes have been performed (ST124-Yes), the process proceeds to ST125.

  In ST125, the state determination means (202, 301) determines whether or not the carry counter 23 is greater than or equal to a predetermined value. When it is determined that the carry counter 23 is equal to or greater than the predetermined value, it is determined that the state is “carry”, the state is stored in the storage means (26, 33) (ST126), the carry counter 23 is cleared (ST127), Return to the beginning of this operation flow. When it is determined that the carry counter 23 is not equal to or greater than the predetermined value (ST125-No), the process proceeds to ST131.

  In ST131, the state determination means (202, 301) calculates the average output value for each axis in the first half and the second half of the sampling period. Then, a difference is calculated for the first half average value for each combination of two different axes (ST132), and a difference is determined for the second half average value for each combination of two different axes (ST133). Further, the state determination means (202, 301) calculates the absolute value by taking the difference between the difference value calculated in the first half and the difference value calculated in the second half for each combination of two different axes (ST134).

  Next, the state determination means (202, 301) determines whether or not all the absolute values calculated in ST134 are equal to or less than a predetermined value (ST135). When all the absolute values calculated in ST134 are equal to or smaller than a predetermined value (ST135-Yes), a variance value of the triaxial composite value during the sampling period is calculated (ST136), and whether or not this variance value is equal to or less than a threshold value. Determine (ST137). When the variance value of the three-axis composite value is equal to or smaller than the threshold value (ST137-Yes), it is determined as the “still” state, the state is stored in the storage means (24, 33) (ST138), and the determination counter 28 is cleared. (ST140), the operation flow returns to the beginning.

  On the other hand, the state determination means (202, 301), when all the absolute values calculated in ST134 are not less than or equal to a predetermined value (ST135-No), or when the variance value of the three-axis composite value is not less than a threshold (ST137-No). The “other motion” state is determined, the state is stored in the storage means (26, 33) (ST139), the determination counter 28 is cleared (ST140), and the process returns to the beginning of this operation flow.

  The embodiments of the present invention have been described above by way of example, but the scope of the present invention is not limited to these embodiments, and can be changed or modified according to the purpose within the scope of the claims. is there.

  In the above-described embodiment, in order to make it easy or difficult to determine the separation, the method of selecting the determination condition (1) to the determination condition (3) is changed, or the predetermined number of times in the determination condition (1) is changed. However, other methods may be used. For example, the same can be realized by changing a predetermined value (T3) in the determination condition (3) or changing thresholds (T1, T2) for determining whether to increase or decrease the determination counter 22. can do.

  Moreover, the subunit | mobile_unit 3 may be equipped with the structure similar to the main | base station 2 mentioned above, and you may enable it to perform the determination of a separation | separation in the subunit | mobile_unit 3, and abnormality notification.

In the above-described embodiment, the request signal is transmitted from the parent device 2 in ST01 of FIG. 4, and the communication processing for receiving the received signal strength from the child device 3 is performed only once in ST02. Instead, for example, the following may be used.
The master unit 2 and the slave unit 3 are provided with a plurality of antennas, and the communication processing described above is performed a plurality of times by switching the antennas. Then, the signal strength detection means of the master unit 2 and the slave unit 3 calculates a representative value from the received signal strength detected by the plurality of times of communication processing, and uses the representative value as a received signal strength as a source of reception level detection. Also good.

  Further, in the above-described embodiment, the reception level detection unit 201 detects the reception level in consideration of the reception signal strength of the slave unit 3 transmitted from the slave unit 3, but the present invention is not limited to this. The received signal strength detected by the second signal strength detecting means 211 may be adopted as the reception level as it is.

DESCRIPTION OF SYMBOLS 1 Separation monitoring apparatus 2 Main | base station 20 Control part 21 Communication means 22 Acceleration sensor 23 Carrying counter 24 Determination counter 25 Continuation counter 26 Storage means 27 Notification means 3 Slave unit 30 Control part 31 Communication means 32 Acceleration sensor 33 Storage means

Claims (3)

Wireless communication is performed between the parent device possessed by the user and the child device attached or possessed to the monitoring target of the user, and the reception level indicating the strength of the received signal in the wireless communication is compared with a predetermined criterion. In the remote monitoring device that performs notification when the determination unit determines that the master unit and the slave unit are separated from each other,
A sensor for detecting movement provided in each of the master unit and the slave unit;
State determination means for determining the movement state of the parent device from the output of the sensor of the parent device, and determining the movement state of the child device from the output of the sensor of the child device;
A combination determination means for determining a combination of the movement state of the parent device and the movement state of the child device;
Reference setting means for setting the predetermined criterion based on the combination;
Equipped with a,
The determination means determines the separation using a first determination criterion as the predetermined criterion.
The state determination means determines whether the parent device is stationary or carried by a person, and whether the child device is stationary or carried by a person,
The combination determination means determines whether one of the movement state of the parent device and the movement state of the child device is a stationary and the other is a carrying combination,
When the combination is determined, the reference setting means sets the predetermined determination reference to a second determination reference that is more easily determined as the separation than the first determination reference. . Before Symbol combination determining means, the motion state of the exercise state and said child machine of the parent device determines whether both carrying the combination,
It said reference setting means, when the combination is determined, apart from monitoring according to claim 1 for setting the predetermined criterion in said first criterion said spaced apart from the determination difficult third criterion than apparatus. The combination determination means determines whether or not the movement state of the parent device and the movement state of the child device are both stationary combinations,
The distance monitoring according to claim 2 , wherein when the combination is determined, the reference setting unit sets the predetermined determination reference to a fourth determination reference that is less likely to be determined as the separation than the third determination reference. apparatus.

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