JP2014183994A - Body motion determination device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a body motion determination device capable of determining the magnitude of body motion in a multistage manner by a simple method through the use of a detection signal of a vibration of the human body.SOLUTION: A body motion determination device 10 includes: vibration sensors 19a-19c and 20a-20c that detect vibrations generated by motion of the human body; a computing part 12 that computes a vibration level of the human body on the basis of detection signals of the vibration sensors 19a-19c and 20a-20c; and a determination part 13 that determines a body motion level of the human body on the basis of a preset linear relation from the vibration level computed by the computing part 12.

Description

  The present invention relates to a body motion determination device that detects body motion by detecting vibrations of a human body.

  In recent years, there are an increasing number of people who have problems related to sleep, such as insomnia and light sleep. If you are unable to get a good quality sleep, you will suffer from drowsiness in the daytime, which will interfere with your daily life. In view of this, there has been provided a device that provides good quality and good sleep by appropriately controlling the awakening light and the vibration pillow according to the sleep state of the person. In such a device, human body information such as heart rate, respiratory rate, and body movement is detected by a sensor, and a sleep state is determined based on the detection result.

  In Patent Document 1, vibration data obtained from an ultrasonic vibration sensor disposed under a human body is grouped every predetermined unit time, for example, every second, and the maximum value and minimum value of vibration data in the group are set. A sleep state estimation system is disclosed in which the difference is the magnitude of the amplitude value, and when it exceeds a specified value, it is determined that body movement has occurred. Thereby, the time when the human body has shifted from non-REM sleep to REM sleep is estimated.

  Patent Document 2 discloses a biological information display device that obtains a pressure distribution (binary image) from pressure-sensitive elements arranged in a matrix under a sleeping person, and determines body movement from a change in the pressure distribution. Yes. This device performs the presence / absence determination of body movement for the sleeper's condition, and further determines the presence / absence of fine movement when there is no body movement. Are classified, and the sleeping posture of the sleeping person is determined based on the classification.

  In Patent Document 3, a plurality of physical activity detection means are attached to a plurality of different parts from the trunk of the human body to the peripheral part of the limb, and obtained from these physical activity detection means from the trunk activity and the peripheral activity. A method is disclosed in which each activity level of the plurality of parts is determined based on output data, and physical activity is determined from each activity level of the plurality of parts and a combination thereof. According to this method, physical activity is discriminated from the activity level of the region on the trunk side, the activity level of the region on the peripheral side, and the combination thereof, so that from a large activity of the body to a small activity with a small number of physical activity detection means. Can be detected / discriminated in detail step by step.

JP 2007-61503 A JP 2005-144042 A JP 2001-87247 A

  However, the sleep state estimation system disclosed in Patent Document 1 has a problem that only the presence or absence of occurrence of body motion in a human body can be determined, and the magnitude of body motion cannot be determined. In the living body information display device disclosed in Patent Document 2, the determination of the sleeping person is performed in two stages in order to classify the sleeping person into three stages, with body movement, with fine movement, and without body movement. There was a problem that became complicated. In the method for discriminating physical activity disclosed in Patent Document 3, it is necessary to attach physical activity detection means (sensors) to a plurality of parts from the trunk to the peripheral part of the limb, and there is a possibility that a person may feel discomfort. there were. In addition, there is a problem that the determination process is complicated in order to determine physical activity from the combination of each activity level.

  In view of the above problems, an object of the present invention is to provide a body motion determination device that can determine the magnitude of body motion in multiple stages by a simple method using a detection signal of human body vibration.

  In order to solve the above-described problem, the characteristic configuration of the body movement determination device according to the present invention is characterized in that at least one sensor for detecting vibration due to movement of the human body and the vibration level of the human body based on a detection signal of the sensor. The calculation unit includes a calculation unit, and a determination unit that determines a body movement level of the human body based on a preset linear relationship from the vibration level calculated by the calculation unit.

  With such a characteristic configuration, the body motion level can be determined by simple calculation based on the vibration level generated by the movement of the human body, and an appropriate body motion level according to the vibration level can be determined. . Moreover, the sensitivity of the determination unit can be easily adjusted by adjusting the slope and intercept of the linear relationship.

  Another characteristic configuration of the body motion determination device according to the present invention includes at least one sensor that detects vibration due to movement of a human body, a calculation unit that calculates a vibration level of the human body based on a detection signal of the sensor, A determination unit that determines a body movement level of the human body based on a preset linear relationship from the vibration level calculated by the calculation unit, and the linear relationship is determined that the body movement level is resting. The vibration level is determined based on the lower limit value of the vibration level and the lower limit value of the vibration level when the body motion level is determined to be low.

  With such a feature configuration, a linear relationship is set based on vibration levels caused by body movements that are often seen during sleep, such as `` rest '' and `` small body movement ''. It can be performed with high accuracy.

  In the body movement determination device according to the present invention, it is preferable that a plurality of the sensors are provided.

  By providing a plurality of sensors within the range in which the human body moves, even if the human body moves, the vibrations can always be detected.

  In the body motion determination device according to the present invention, it is preferable to calculate the vibration level after weighting a plurality of the sensors.

  With such a configuration, for example, weighting can be used for vibration generated in a place where a human body exists, so that the body motion of the human body can be determined more accurately.

  In the body movement determination device according to the present invention, it is preferable that the vibration level is a maximum absolute amplitude value of the detection signal detected within a predetermined time.

  With such a configuration, it is possible to determine the maximum body movement level generated within a predetermined time.

  In the body movement determination device according to the present invention, it is preferable that the vibration level is a sum of energy of the detection signals detected within a predetermined time.

  With such a configuration, it is possible to determine the body motion level based on the vibration level generated throughout the predetermined time, not the body motion that occurs instantaneously.

It is a perspective view showing the bedding provided with the body movement determination apparatus. It is the schematic showing the structure of a vibration sensor assembly. It is a figure which illustrates the detection signal of each vibration sensor output from a vibration sensor assembly. It is a block diagram of the whole system containing a body movement determination apparatus. It is a flowchart which determines a body movement in the body movement determination apparatus which concerns on 1st Embodiment. It is a graph showing the relationship between the vibration level and body movement level in a determination part. It is a flowchart which determines a body movement in the body movement determination apparatus which concerns on the modification of 1st Embodiment. It is a figure showing the square sum of the detection signal of each vibration sensor output from a vibration sensor assembly. It is a figure showing the evaluation value output from a calculating part. It is a perspective view which shows the vehicle seat provided with the body movement determination apparatus which concerns on 2nd Embodiment.

[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view showing a bed 1 provided with a body movement determination device 10 according to the present embodiment. The bed 1 includes a body movement determination device 10, a mattress 28, and a headboard 29 with illumination. The mattress 28 is placed on the bed frame 30 of the bed 1, and the body movement determination device 10 includes a vibration sensor assembly 18 installed between the bottom surface of the mattress 28 and the top surface of the bed frame 30, The signal processing unit 11 processes a signal output from the vibration sensor assembly 18. The vibration sensor assembly 18 includes two sensor assembly sheets 19 and 20. The sensor assembly sheets 19 and 20 are installed so that the longitudinal direction thereof is parallel to the lateral direction of the mattress 28 and is located around the scapula and the buttocks of the human body 2 lying on the bed 1.

  FIG. 2 is a schematic view showing the configuration of the vibration sensor assembly 18. As shown in FIG. 2, the sensor assembly sheets 19 and 20 have the same size, and have a rectangular shape with a longitudinal length of about 600 millimeters and a short side length of about 150 millimeters. Three vibration sensors 19 a, 19 b, 19 c are built in the sensor assembly sheet 19, and three vibration sensors 20 a, 20 b, 20 c are built in the sensor assembly sheet 20. These vibration sensors 19a, 19b, 19c, 20a, 20b, and 20c (hereinafter, when the six vibration sensors are collectively expressed, they are referred to as vibration sensors 19a to 19c and 20a to 20c) detect vibrations of the human body 2. Then, a detection signal corresponding to the magnitude of the vibration is output. The vibration sensors 19a to 19c and 20a to 20c are examples of sensors in the present invention. FIG. 3 shows examples of detection signals output from the vibration sensor assembly 18 by the vibration sensors 19a to 19c and 20a to 20c.

  Next, processing of detection signals output from the vibration sensors 19a to 19c and 20a to 20c will be described with reference to FIGS. FIG. 4 is a block diagram of the entire system including the body movement determination device 10. The body movement determination device 10 detects vibrations generated by the human body 2 by movements of turning over on the bed 1 and movements of the extremities by vibration sensors 19a to 19c and 20a to 20c, and the human body based on the detection signals. 2 is a device for determining a body movement level of 2. The signal processing unit 11 of the body movement determination device 10 includes a calculation unit 12 and a determination unit 13. In the calculation part 12, the signal of the vibration level used for body movement determination is produced | generated from the input detection signal of the vibration sensors 19a-19c and 20a-20c. The determination unit 13 determines the body movement level based on the vibration level signal output from the calculation unit 12 and outputs the result.

  FIG. 5 shows a processing flow for determining the body motion level of the human body 2 lying on the bed 1 in the body motion determination device 10. In the body motion determination device 10 according to this embodiment, the vibration sensors 19a to 19c and 20a to 20c each output detection signals at intervals of 0.01 seconds, and detection signals up to that point, that is, detection signals of 12000 every 20 seconds. The maximum value is extracted from, and the body movement of the human body 2 is determined based on the maximum value. The detection intervals of the vibration sensors 19a to 19c and 20a to 20c are not limited to 0.01 seconds, and the intervals may be longer or shorter than this. Further, the extraction of the maximum value is not limited to every 20 seconds, and the interval may be longer or shorter than this.

  As shown in the flow of FIG. 5, when vibration is detected by the vibration sensors 19 a to 19 c and 20 a to 20 c (S 51), a detection signal is output for each sensor, and six detection signals are calculated by the calculation unit of the signal processing unit 11. 12 is input. The six detection signals input to the calculation unit 12 are converted into absolute values (S52), and then the maximum absolute value, that is, the maximum value is extracted (S53). The extracted maximum value is compared with the maximum value of the detection signal accumulated in the past, and the larger maximum value is stored in a RAM (not shown) or the like (S54). The above processing is performed for 20 seconds (S55), and the maximum value of the detection signals of the vibration sensors 19a to 19c and 20a to 20c for 20 seconds is output as a vibration level signal (hereinafter also simply referred to as a vibration level). , Input to the determination unit 13.

  Based on the vibration level output from the calculation unit 12, the determination unit 13 sets the body motion level in five stages of “absence”, “rest”, “body motion small”, “body motion”, and “body motion large”. Determine (S56). In the determination unit 13, it is determined that a larger body movement has occurred as the vibration level is higher. In the present embodiment, a linear function formula is used to calculate the body movement level from the vibration level. Therefore, as shown in FIG. 6, between the vibration level and the body movement level, when the lower limit values of the vibration levels that are the basis for the determination of each body movement level are connected, a linear relationship that forms a straight line is obtained. Have. Thus, by calculating the body motion level with a linear function equation, the body motion level value can be obtained by simple calculation, and an appropriate body motion level according to the vibration level can be determined. Further, the sensitivity of the determination unit 13 can be easily adjusted by adjusting the slope and intercept of the linear function.

  Next, a method for determining a linear function formula will be described. First, the human body 2 actually moves on the bed 1 so that the body motion level is in the “rest” state and the “body motion small” state, and the vibration level at that time is measured. Then, the lower limit value of the vibration level determined to be “rest” is defined as X1, and the lower limit value of the vibration level determined to be “low body movement” is defined as X2, and the vibration level is equal to or greater than X1 and X2. Decide that when it is less than "rest". At this time, the difference between the vibration level X2 and the vibration level X1, that is, the increase amount of the vibration level from the vibration level X1 to X2 is defined as DX. Then, a value obtained by adding the same increase amount DX to the vibration level X2 is determined as the lower limit value X3 of the vibration level determined as “being in motion”, and a value obtained by adding the same increase amount DX to the vibration level X3 is determined as “body movement large”. The lower limit value X4 of the vibration level to be set is determined. In this way, the amount of increase in the vibration level necessary for the body motion level to increase by one level (body motion increases) can be made constant, and the relationship between the vibration level and the body motion level is linearly related. Can be.

  The body movement level of the human body 2 is actually determined on the bed 1 while the human body 2 is sleeping (sleeping). At this time, most of the body movement level of the human body 2 is “rest” or “small body movement”. is there. Therefore, as described above, the correlation between the vibration level and the body motion level is calculated based on the lower limit value X1 of the vibration level determined as “rest” and the lower limit value X2 of the vibration level determined as “small body motion”. By determining the linear function as a linear relationship, the body motion level of the human body 2 can be accurately determined by a simple method.

  When the determination unit 13 determines the body movement level, the determination result is output to the controller 23 (S57). If the body movement determination is not continued (Yes in S58), the body movement determination ends. If the body movement determination is continued (No in S58), the vibration level input to the determination unit 13 is reset (S59), and the next body movement determination cycle is started.

  Generally, it is said that the greater the body movement of the human body 2, the shallower the sleep depth. As shown in FIG. 4, the controller 23 provides lighting 24, an air conditioner 25, a curtain 26, a vibration pillow 27, and the like to provide a comfortable and high quality sleep environment for the human body 2 according to the determination result of the body movement level. Control is performed so as to achieve an optimum state according to the determined body movement level.

  With this configuration, the body movement level can be detected based on the maximum vibration level generated in 20 seconds. Moreover, in the bed 1 provided with the body movement determination apparatus 10 according to the present embodiment, the body movement determination apparatus 10 determines not only the presence / absence of the human body 2 but also the magnitude of the body movement of the human body 2. It is possible to provide a more comfortable and high quality sleep environment.

  In the present embodiment, vibrations of the human body 2 are detected using the vibration sensors 19a to 19c and 20a to 20c, but the present invention is not limited to this. A device that can indirectly acquire vibration of the human body 2 such as an air pressure sensor or an acceleration sensor can also be used. Further, the number of vibration sensors is not limited to six. One or more pieces are necessary to detect the vibration of the human body 2, but the number may be more or less than six as long as the vibration can be accurately detected.

  In the present embodiment, the detection signals of the vibration sensors 19a to 19c and 20a to 20c are directly input to the calculation unit 12 of the body movement determination device 10, but the present invention is not limited to this. In order to efficiently extract a signal related to vibration, a filter process may be performed on the detection signal to remove a noise component and then input to the calculation unit 12.

  In the present embodiment, the linear function formula is used for the calculation of the body movement level in the determination unit 13, but the present invention is not limited to this. For example, a quadratic function expression or an exponential function expression may be used.

[Modification of First Embodiment]
Next, the modification of 1st Embodiment of this invention is demonstrated based on drawing. In the following description of the modified examples, the same reference numerals are given to the same components as those in the first embodiment, and the descriptions regarding the same components are omitted. In the body movement determination device 10 of this modification, the processing method of the detection signals of the vibration sensors 19a to 19c and 20a to 20c in the calculation unit 12 is different from that of the first embodiment, and the sum of the energy of the detection signals is calculated. Then, it is set as an input value (vibration level) to the determination unit 13. Other structures are the same.

  FIG. 7 shows a processing flow for determining the body motion level of the human body 2 lying on the bed 1 in the body motion determination device 10 according to this modification. As shown in the flow of FIG. 7, when vibration is detected by each of the vibration sensors 19 a to 19 c and 20 a to 20 c (S 71), a detection signal is output for each sensor, and six detection signals are calculated by the calculation unit of the signal processing unit 11. 12 is input. The six detection signals input to the calculation unit 12 are squared (S72), and then the square values of the six detection signals are summed (S73). In the body movement determination device 10, the vibration sensors 19a to 19c and 20a to 20c output detection signals at intervals of 0.01 seconds, respectively, as in the first embodiment, and determine body movements of the human body 2 every 20 seconds. Therefore, the calculation unit 12 sequentially accumulates the sum of squares of six detection signals output every 0.01 second until 20 seconds elapse (S74, S75), and the sum of squares of 2000 is an evaluation value, that is, energy of the detection signal. Is output as the sum of The output evaluation value is input to the determination unit 13 as a vibration level. FIG. 8 is a diagram illustrating an example of the sum of squares of detection signals of the six vibration sensors 19a to 19c and 20a to 20c. FIG. 9 shows an example of an evaluation value obtained by integrating the square sum of the detection signals for 20 seconds.

  In the determination unit 13, as in the first embodiment, five stages of “absence”, “rest”, “small body motion”, “during body motion”, and “large body motion” based on the input value from the calculation unit 12. The body movement level is then determined (S76). However, in the first embodiment, the input value is the maximum value of the detection signals of the vibration sensors 19a to 19c and 20a to 20c for 20 seconds, whereas in this modification, the sum of squares of the detection signals is integrated for 20 seconds. Since the evaluation value becomes the input value, the vibration level lower limit values X1, X2, X3, and X4 are different from those in the first embodiment. However, the lower limit values X3 and X4 are determined on the basis of the lower limit value X1 at which the body motion level is determined to be "rest" and the lower limit value X2 at which the body motion level is determined to be "small body motion". The calculation of the dynamic level is the same as in the first embodiment.

  With this configuration, the body movement level can be detected based on the vibration level generated over 20 seconds.

  In the first embodiment and this modification, the detection signals of the six vibration sensors 19a to 19c and 20a to 20c are processed equally. However, the present invention is not limited to this, and the detection signals are weighted and processed. May be. For example, a load sensor is disposed adjacent to each of the vibration sensors 19a to 19c and 20a to 20c, and the load from the load sensor is also detected simultaneously with the detection signals of the vibration sensors 19a to 19c and 20a to 20c. . Then, a load sensor in which a large load is generated is identified based on detection signals from the six load sensors, and weighting is performed so as to increase the detection signal from the vibration sensor adjacent to the load sensor, thereby calculating the arithmetic unit 12. In this case, signal processing may be performed. By adopting such a configuration, it is possible to determine the body movement by weighting the vibration generated in the place where the human body 2 exists, so that the body movement of the human body 2 can be determined more accurately.

  In the first embodiment and the present modification, the maximum value of the detection signals of the vibration sensors 19a to 19c and 20a to 20c (first embodiment) or the energy of the detection signal every predetermined time (20 seconds) as the vibration level. Although the total sum (modified example) is configured to be input to the determination unit 13, the present invention is not limited to this. For example, the average amplitude value of the detection signals of the vibration sensors 19 a to 19 c and 20 a to 20 c for 20 seconds may be input to the determination unit 13.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. FIG. 10 is a schematic diagram of the vehicle seat 3 representing the second embodiment. This vehicle is equipped with a body movement determination device 10. The signal processing unit 11 is mounted on the ECU 39, and the vibration sensor assembly 18 is built in the backrest portion of the vehicle seat 3.

  Since the configuration and operation of the body movement determination device 10 are the same as those of the first embodiment or the modification thereof, detailed description thereof is omitted. However, in the present embodiment, the body movement determination device 10 is mounted on a vehicle, and its purpose is to prevent a drowsy driving. Therefore, for example, when it is determined that the body movement level is “rest” continuously a predetermined number of times, the controller 23 on the ECU 39 determines that the driver is in a strong sleepiness or sleep state and prompts the driver to wake up. To control various devices. For example, the sleep / wake device 41 that gives some stimulus to the driver is operated. Alternatively, the driver may be awakened by other methods such as blowing air from an air conditioner (not shown) on the driver's face or increasing the volume of an in-vehicle acoustic device (not shown).

  INDUSTRIAL APPLICABILITY The present invention can be used for a body movement determination device that detects body movement by detecting vibrations of a human body.

2 human body 10 body movement determination device 12 calculation unit 13 determination unit 19a vibration sensor (sensor)
19b Vibration sensor (sensor)
19c Vibration sensor (sensor)
20a Vibration sensor (sensor)
20b Vibration sensor (sensor)
20c Vibration sensor (sensor)

Claims (6)

At least one sensor for detecting vibration caused by movement of the human body;
A calculation unit that calculates a vibration level of the human body based on a detection signal of the sensor;
A body movement determination apparatus comprising: a determination unit that determines a body movement level of the human body based on a preset linear relationship from the vibration level calculated by the calculation unit. At least one sensor for detecting vibration caused by movement of the human body;
A calculation unit that calculates a vibration level of the human body based on a detection signal of the sensor;
A determination unit that determines a body movement level of the human body based on a preset linear relationship from the vibration level calculated by the calculation unit;
The linear relationship is determined based on a lower limit value of the vibration level when the body motion level is determined to be resting and a lower limit value of the vibration level when the body motion level is determined to be low body motion. Body movement determination device.   The body movement determination apparatus according to claim 1, comprising a plurality of the sensors.   The body motion determination device according to claim 3, wherein the calculation unit calculates the vibration level after weighting a plurality of the sensors.   The body motion determination device according to any one of claims 1 to 4, wherein the vibration level is a maximum absolute amplitude value of the detection signal detected within a predetermined time.   5. The body movement determination device according to claim 1, wherein the vibration level is a sum of energy of the detection signals detected within a predetermined time.

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