Bed-leaving sensor and bed-leaving detection method

Patent metadata

Field	Value
Publication number	US-9782108-B2
Application number	US-201514862651-A
Country	US
Kind code	B2
Filing date	Sep 23, 2015
Priority date	Jun 28, 2013
Publication date	Oct 10, 2017
Grant date	Oct 10, 2017

Abstract

A bed-leaving sensor for detecting bed-leaving by a user on a bed, including: a sitting position detection member that detects a sitting position of the user based on a detection value of a pressure sensor arranged on the bed; a foot movement detection member for detecting foot movement of the user based on the detection value of the pressure sensor; and a bed-leaving behavior detection member that detects bed-leaving behavior of the user with the sitting position or the foot movement being detected within a preset bed-leaving expectation region as a condition.

First claim

What is claimed is:

1. A bed-leaving sensor for detecting bed-leaving by a user on a bed, comprising:
a sitting position detection member that detects a sitting position of the user based on a detection value of a pressure sensor arranged on the bed;
a foot movement detection member for detecting foot movement of the user based on the detection value of the pressure sensor; and
a bed-leaving behavior detection member that detects bed-leaving behavior of the user with the sitting position or the foot movement being detected within a preset bed-leaving expectation region as a condition,
wherein the sitting position detection member sets a determination area in a periphery of a pressure sensing center of a region in which pressure of a given contact threshold value or greater is detected within a preset sitting position determination region on the pressure sensor provided on the bed-leaving, expectation region, and the sitting position is detected based on fulfilling all the following requirements:
a ratio of a total pressure detected within the determination area occupying a total pressure detected within the sitting position determination region is a designated threshold value or greater;
a breadth of the region in which the pressure of the contact threshold value or greater is detected within the sitting position determination region is a designated value or greater; and
the total pressure detected within the sitting position determination region is a designated threshold value or greater, and

wherein the foot movement detection member detects the foot movement based on fulfilling all the following requirements:
a breadth of a region in which pressure of a given contact threshold value or greater has been detected within a preset foot pressure detection region on the pressure sensor provided on the bed-leaving expectation region is within a designated range;
a total pressure detected within the foot pressure detection region across a given time is a designated threshold value or greater; and
a maximum pressure value detected within the foot pressure detection region is a preset threshold value or greater.

2. The bed-leaving sensor according to claim 1 , wherein the bed-leaving expectation region is set to be a foot side region on the bed.

3. The bed-leaving sensor according to claim 1 , wherein the pressure sensor is arranged only at a bed-leaving possibility region on the bed.

4. The bed-leaving sensor according to claim 1 , wherein the pressure sensing center is a center of gravity of the region in which the pressure of the contact threshold value or greater is detected with the pressure sensor.

5. The bed-leaving sensor according to claim 1 , wherein the pressure sensing center is an area center of the region in which the pressure of the contact threshold value or greater is detected with the pressure sensor.

6. The bed-leaving sensor according to claim 1 , further comprising a notification member for notifying that the bed-leaving behavior of the user has been detected.

7. A bed-leaving detection method for detecting bed-leaving by a user on a bed, comprising:
a sitting position detection step for detecting a sitting position of the user based on a detection value of a pressure sensor arranged on the bed;
a foot movement detection step for detecting foot movement of the user based on the detection value of the pressure sensor; and
a bed-leaving behavior detection step for detecting bed-leaving behavior of the user with the sitting position or the foot movement being detected within a preset bed-leaving expectation region as a condition,
wherein with the sitting position detection step, a determination area is set in a periphery of a pressure sensing center of a region in which pressure of a given contact threshold value or greater is detected within a preset sitting position determination region on the pressure sensor provided on the bed-leaving expectation region, and the setting position is detected based on fulfilling all the following requirements:
a ratio of a total pressure detected within the determination area occupying a total pressure detected within the sitting position determination region is a designated threshold value or greater;
a breadth of the region in which the pressure of the contact threshold value or greater is detected within the sitting position determination region is a designated value or greater; and
the total pressure detected within the sitting position determination region is a designated threshold value or greater, and

wherein the foot movement detection step detects the foot movement based on fulfilling all the following requirements:
a breadth of a region in which pressure of a given contact threshold value or greater is detected within a preset foot pressure detection region on the pressure sensor provided on the bed-leaving expectation region is within a designated range;
a total pressure detected within the foot pressure detection region across a given time is a designated threshold value or greater, and
a maximum pressure value detected within the foot pressure detection region is a preset threshold value or greater.

8. The bed-leaving detection method according to claim 7 , wherein a foot side region on the bed is set as the bed-leaving expectation region.

Assignees

• Sumitomo Riko Co Ltd

Inventors

• Shimizu Atsuki

Classifications

• A61G2203/34

  for pressure · CPC title

• A61B5/1115 Primary

  Monitoring leaving of a patient support, e.g. a bed or a wheelchair · CPC title

• G08B21/0461

  integrated or attached to an item closely associated with the person but not worn by the person, e.g. chair, walking stick, bed sensor · CPC title

• G08B21/22

  responsive to presence or absence of persons · CPC title

• G08B29/185

  Signal analysis techniques for reducing or preventing false alarms or for enhancing the reliability of the system · CPC title