Load Body State Judging Device, Vehicle Seat And Computer Program

• US 20070299636A1
• Filed: 03/22/2005
• Published: 12/27/2007
• Est. Priority Date: 03/25/2004
• Status: Active Grant

• Current Assignee: Delta Tooling Co., Ltd. (Delta Kogyo Company Limited)
• Original Assignee: Delta Tooling Co., Ltd. (Delta Kogyo Company Limited)
• Inventors: Fujita, Etsunori, Enokizono, Masato
• Granted Patent: US 7,496,457 B2
• Time in Patent Office: Days
• US Class Current: 702/191
• CPC Class Codes: A61B 2503/22 Motor vehicles operators, e.g. drivers, pilots, captains
• CPC Class Codes: A61B 5/1116 Determining posture transitions
• CPC Class Codes: A61B 5/18 for vehicle drivers or machine operators
• CPC Class Codes: A61B 5/4809 Sleep detection, i.e. determining whether a subject is asleep or not
• CPC Class Codes: A61B 5/6887 mounted on external non-worn devices, e.g. non-medical devices
• CPC Class Codes: A61B 5/6893 Cars
• CPC Class Codes: B60N 2/002 Seats provided with an occupancy detection means mounted therein or thereon detection means responsive to presence or absence of children B60N2/266
• CPC Class Codes: B60N 2/0022 for sensing anthropometric parameters, e.g. heart rate or body temperature
• CPC Class Codes: B60N 2/0023 for detection of driver fatigue
• CPC Class Codes: B60N 2/0025 by using weight measurement
• CPC Class Codes: B60N 2/0026 for distinguishing between humans, animals or objects
• CPC Class Codes: B60N 2/0029 for detecting the motion of the occupant
• CPC Class Codes: B60N 2/003 characterised by the sensor mounting location in or on the seat
• CPC Class Codes: B60N 2002/981 Warning systems, e.g. the seat or seat parts vibrates to warn the passenger when facing a danger
• CPC Class Codes: B60N 2210/40 Force or pressure sensors

Abstract

The present invention makes it possible to easily perform judgment of a mental-and-physical state, and distinction between a person and a thing.

A load body state is judged from time series data of an emphasis displacement inclination obtained by collecting displacement signal data of the load body state using a displacement signal collection sensor 10, determining a rate of change for every arbitrary interval of an original waveform as an original waveform displacement inclination at an operating unit 20, and at the same time, determining time series data of an average displacement inclination for every prescribed time period range from a plurality of original waveform displacement inclinations, and by determining an emphasis displacement inclination through slide calculation of time series data of the average displacement inclination for every prescribed sampling time. Accordingly, it is possible to obtain time series data in which wobbling-like fluctuation peculiar to a low frequency living body displacement signal is emphasized by determining an emphasis displacement inclination from an original displacement inclination and an average displacement inclination even when vibration or the like transmitted from a road surface during traveling of a car is contained in the displacement signal data collected by the displacement signal collection sensor 10.

Claims

1. A load body state judging device to judge a state of a load body by analyzing signal data obtained by a displacement signal collection sensor which can collect a living body displacement signal of the load body supported by a load body supporting means, comprising:

an average displacement inclination operating means to divide an original waveform of signal data obtained by said displacement signal collection sensor into each prescribed time range and determine a rate of change of the signal data in the prescribed time range as a average displacement inclination;

an emphasis displacement inclination operating means to determine an emphasis displacement inclination by slide-calculating a rate of change of an average displacement inclination for each prescribed sampling time at a prescribed slide lap rate over prescribed number of times from time series data of said average displacement inclination so that the time series data of the emphasis displacement inclination is obtained; and

a state judging means to judge a load body state from the time series data of the emphasis displacement inclination obtained by said emphasis displacement inclination operating means.

2. The load body state judging device according to claim 1, wherein said displacement signal collection sensor is attached to the load body supporting means.

3. The load body state judging device according to claim 1, wherein said average displacement inclination operating means comprises:

an original waveform displacement inclination operating means to divide an original waveform of signal data obtained by said displacement signal collection sensor into each prescribed time range, and further divide it within the prescribed time range into a plurality of intervals, and obtain a rate of change for each interval as an original waveform displacement inclination; and

an original waveform displacement inclination summing means to sum up each original waveform displacement inclination obtained by said original waveform displacement inclination operating means,

wherein the sum up value obtained by said original waveform displacement inclination summing means is structured to be established as an average displacement inclination.

4. The load body state judging device according to claim 3, wherein said original waveform displacement inclination operating means is structured to obtain the rate of change for each interval as said original waveform displacement inclination, taking the distance between respective intersecting points of an envelope on the lower limit side, or a curved line nearly parallel to either envelope, and the original waveform as an interval.

5. The load body state judging device according to claim 1, wherein a sampling time interval used for slide-calculation of said emphasis displacement inclination operating means is 180 seconds, and a slide lap rate is 90%.

6. The load body state judging device according to claim 1, wherein said state judging means comprises at least any one means out of a type judging means to judge the type of the load body and a mental-and-physical state judging means to judge the mental-and-physical state when the load body is a person.

7. The load body state judging device according to claim 6, wherein said mental-and-physical state judging means judges when the amplitude range of time series data of said emphasis displacement inclination gets relatively large compared with the amplitude before or after the range as a hypnagogic transition period between an awakening state and a sleeping state.

8. The load body state judging device according to claim 6, wherein said type judging means comprises a means to judge a load body to be a thing when the time series data of said emphasis displacement inclination are in transition within a prescribed range, and to be a person when in transition with an inclination change exceeding the prescribed range.

9. The load body state judging device according to claim 7, wherein said type judging means comprises a comparison means to read and compare a reference patter of time series data of the emphasis displacement inclination stored in a storage unit in advance and specify an individual when the time series data of said emphasis displacement inclination are in transition with an inclination change exceeding a prescribed range.

10. The load body state judging device according to claim 1, wherein said load body supporting means is a vehicle seat, and said displacement signal collection sensor is structured to be attached to at least any one portion out of a seat cushion, a seat back, or a headrest, and to detect pressure fluctuation based on a living body displacement signal of the load body.

11. The load body state judging device according to claim 10, wherein said load body supporting means is a vehicle seat, and said displacement signal collection sensor is structured to be attached to at least any one portion of a seat cushion of the vehicle seat, and to detect pressure fluctuation based on a living body displacement signal via the muscles of the buttocks of the load body.

12. The load body state judging device according to claim 1, wherein said load body supporting means is a vehicle seat, and said displacement signal collection sensor is structured to detect a displacement amount of a member displacing based on a living body displacement signal of the load body.

13. The load body state judging device according to claim 12, wherein said displacement signal collection sensor detecting a displacement amount of a member displacing based on a living body displacement signal of the load body serves as a load detection means to detect the load of the load body.

14. The load body state judging device according to claim 1, further comprising a load detection means detecting the load of the load body separately from said displacement signal collection sensor.

15. The load body state judging device according to claim 9, further comprising a load detection means detecting the load of the load body separately from said displacement signal collection sensor,

wherein said comparison means compares the load of the load body obtained by said load detection means with a reference load stored in a storage unit in advance to judge at least any one factor out of physique size, distinction between an adult and a child, and identification of an individual while adding the load to the comparison factors as one factor.

16. The load body state judging device according to claims 14 or 15, wherein said load detection means is a displacement detection mechanism to detect a displacement amount of a member displacing based on the load of a load body among the load body supporting means.

17. A vehicle seat, comprising:

a displacement signal collection sensor provided at least any one portion of a seat cushion, a seat back, and a headrest which are load body supporting units, and is able to collect displacement of the load body supporting unit due to a living body signal of the load body supported by said load body supporting unit; and

a load body state judging device to analyze signal data obtained from said displacement signal collection sensor and judge the state of the load body,

wherein said load body state judging device comprises;

an average displacement inclination operating means to divide an original waveform of signal data obtained by said displacement signal collection sensor into each prescribed time range and to determine a rate of change of the signal data in the prescribed time range as an average displacement inclination;

an emphasis displacement inclination operating means to obtain a rate of change of an average displacement inclination for each prescribed sampling time period from time series data of said average displacement inclination by slide calculating at a prescribed slide lap rate over prescribed number of times as the emphasis displacement inclination so as to obtain time series data of the emphasis displacement inclination; and

a state judging mans judging a load body state from time series data of the emphasis displacement inclination obtained by said emphasis displacement inclination operating means.

18. The vehicle seat according to claim 17,

wherein said load body supporting unit comprises:

a vibration-removal mechanism having a small spring constant in an equilibrium state; and

a cushion mechanism arranged to provide with a spring characteristic closely analogous to the spring characteristics of a human muscle,

wherein

said displacement signal collection sensor is disposed between said vibration-removal mechanism and the cushioning mechanism.

19. The vehicle seat according to claim 18, wherein said displacement signal collection sensor is disposed between a base cushioning material disposed in a seat cushion and included in said vibration-removal mechanism and a surface layer cushioning material strained on a cushion frame disposed in a seat cushion and included in said cushioning mechanism, and is able to collect a living body displacement signal via the muscles of the buttocks.

20. The vehicle seat according to claim 17,

wherein the average displacement inclination operating means of said load body state judging device comprises:

an original waveform displacement inclination operating means to divide an original waveform of signal data obtained from said displacement signal collection sensor into each prescribed time range, and further divide it within the prescribed time range into a plurality of intervals, and obtain a rate of change for each interval as an original waveform displacement inclination; and

an original waveform displacement inclination summing means to sum up each original waveform displacement inclination obtained by said original waveform displacement inclination operating means,

wherein the sum up value obtained by said original waveform displacement inclination summing means is structured to be established as an average displacement inclination.

21. The vehicle seat according to claim 20, wherein the original waveform displacement inclination operating means of said load body state judging device is structured to obtain the rate of change for each interval as said original waveform displacement inclination, taking the distance between respective intersecting points of an envelope on the upper limit side of the amplitude of an original waveform, an envelope on the lower limit side, or a curved line nearly parallel to either envelope, and the original waveform as an interval.

22. The vehicle seat according to claim 17, wherein a sampling time interval used for slide-calculation of said emphasis displacement inclination operating means included in the load body state judging device is 180 seconds, and a slide lap rate is 90%.

23. The vehicle seat according to claim 17, wherein the state judging means of said load body state judging device comprises at least any one means out of a type judging means to judge the type of the load body and a mental-and-physical state judging means to judge the mental-and-physical state when the load body is a person.

24. The vehicle seat according to claim 23, wherein said mental-and-physical state judging means judges when the amplitude range of time series data of said emphasis displacement inclination gets relatively large compared with the amplitude before or after the range as a hypnagogic transition period between an awakening state and a sleeping state.

25. The vehicle seat according to claim 23, wherein said type judging means comprises a means to judge a load body to be a thing when the time series data of said emphasis displacement inclination are in transition within a prescribed range, and to be a person when in transition with an inclination change exceeding the prescribed range.

26. The vehicle seat according to claim 17, further comprising a load detection means detecting the load of a load.

27. The vehicle seat according to claim 23, further comprising a load detection means detecting the load of a load body,

wherein the comparison means compares the load of the load body obtained by the load detection means with a reference load stored in a storage unit in advance to judge at least any one factor out of physique size, distinction between an adult and a child, and identification of an individual while adding the load to the comparison factors as one factor.

28. A computer program to analyze signal data obtained from a displacement signal collection sensor which is able to collect a living body displacement signal of the load body supported by the load body supporting means and to make a computer execute a process for judging a load body state, said computer program comprising:

an average displacement inclination operating step to divide an original waveform of signal data obtained by said displacement signal collection sensor into each prescribed time range and determine a rate of change of the signal data in the prescribed time range as an average displacement inclination;

an emphasis displacement inclination operating step to determine an emphasis displacement inclination for each prescribed sampling time at a prescribed slide lap rate over a prescribed number of times from time series data of the average displacement inclination so that the time series data of the emphasis displacement inclination is obtained; and

a state judging step to judge a load body state from the time series data of the emphasis displacement inclination obtained by said emphasis displacement inclination operating step.

29. The computer program according to claim 28, wherein said average displacement inclination operating steps comprises:

an original waveform displacement inclination operating step to divide an original waveform of signal data obtained by said displacement signal collection sensor into each prescribed time range, and further divide it within the prescribed time range into a plurality of intervals, and obtain a rate of change for each interval as an original waveform displacement inclination; and

an original waveform displacement inclination summing step to sum up each original waveform displacement inclination obtained by said original waveform displacement inclination operating step,

wherein the sum up value obtained by said original waveform displacement inclination summing step is structured to be establish as an average displacement inclination.

30. The computer program according to claim 29, wherein said original waveform displacement inclination operating step is structured to obtain the rate of change for each interval as said original waveform displacement inclination, taking the distance between respective intersecting points of an envelope on the upper limit side of the amplitude of an original waveform, an envelope on the lower limit side, or a curved line nearly parallel to either envelope, and the original waveform as an interval.

31. The computer program according to claim 28, wherein a sampling time interval used for slide-calculation of said emphasis displacement inclination operating step is 180 seconds, and a slide lap rate is 90%.

32. The computer program according to claim 28, wherein said state judging step comprises at least any one step out of a type judging step to judge the type of the load body and a mental-and-physical state judging step to judge the mental-and-physical state when the load body is a person.

33. The computer program according to claim 32, wherein said mental-and-physical state judging step judges when the amplitude range of the time series data of the emphasis displacement inclination getting relatively large compared with the amplitude before or after the range as in a hypnagogic transition period between an awakening state and a sleeping state.

34. The computer program according to claim 32, wherein said type judging step includes a means to judge the load body as a thing when the time series data of the emphasis displacement inclination are in transition within a prescribed range, and as a person when in transition with an inclination change exceeding the prescribed range.