Apparatuses and methods for determining performance parameters of a flexible surface

Patent metadata

Field	Value
Publication number	US-2016356676-A1
Application number	US-201414901295-A
Country	US
Kind code	A1
Filing date	Jul 9, 2014
Priority date	Jul 12, 2013
Publication date	Dec 8, 2016
Grant date	—

Abstract

A method is provided for determining a characteristic of a flexible surface and determining a performance parameter of the flexible surface is disclosed. The method comprises providing a test device and pressing the test device into a flexible surface, measuring the pressures at the sensing points, and determining an envelopment parameter of the surface based on the pressures. The test device comprises a plurality of sensing points extending from a bottom of the test device upwardly along a side of the test device. A test indentor comprising a shell, wherein a least a portion of the shell is generally round in shape and has an exterior, with sensing points extending along the side of the shell, each sensing point is capable of detecting pressure at its location and an elastomeric material is on the exterior of the shell and adjacent the sensing points.

First claim

1 . A method for determining a characteristic of a flexible surface, the method comprising:
providing a test device at least part of which having a bottom area and side area, the test device comprising a plurality of sensing points extending from the bottom upwardly toward the side; pressing the test device into a flexible surface; measuring the pressures at the sensing points; and determining an envelopment parameter of the surface based on the pressures.

2 . The method as recited in claim 1 , wherein the determining operation comprises:
determining the contact depth based upon the highest location of a sensing point where a nominal pressure is sensed.

3 . The method as recited in claim 1 , wherein the determining operation comprises:
determining the contact area of the test device using the sensing points, and the immersed area of the test device using the distance.

4 . The method as recited in claim 3 , wherein the determining operation comprises:
determining percent envelopment by dividing the contact area by the immersed area.

5 . The method as recited in claim 1 , wherein the Jest device comprises a flexible material adjacent the sensing points.

6 . The method as recited in claim 5 , wherein the test device comprises a hemispherical shell, wherein the flexible material comprises a gel adhered to the exterior of the shell, and wherein the sensing points comprise concentric rings of sensors spaced along the exterior of the shell.

7 .- 21 . (canceled)

22 . A method for determining a characteristic of a patient support surface, the method comprising:
pressing a test device into a patient support surface, wherein at least part of the test device has a generally rounded shape having a bottom area and a side area, the test device comprising a plurality of sensing points extending from the bottom upwardly toward the side; measuring the pressures at the sensing points; transmitting signals representing the pressures from the sensing points to a data device; storing pressure data representing the pressures in the data device; and determining an envelopment parameter of the surface based on the pressure data.

23 . The method as recited in claim 22 , wherein the pressing operation is carried out at a controlled force by a measuring device.

24 . The method as recited in claim 23 , wherein the measuring device comprises a force displacement measuring device.

25 . The method as recited in claim 23 , wherein the measuring device presses the test device into the patient support surface at a known force and records displacement data indicating how far the test device has been pressed into the patient support surface.

26 . The method as recited in claim 25 , wherein the envelopment parameter is determined based on a contact area determined from the pressure data and an immersion parameter determined from the displacement data.

27 . The method as recited in claim 22 , wherein the envelopment parameter is determined by dividing the contact area (CA) by the immersion area (IA), wherein CA and 1A are calculated by the following formulas:
CA=2 *π*r *(contact depth) 1 A= 2 *π*r *(immersion depth), wherein r is the radius of the generally rounded shape.

28 . The method as recited in claim 27 , wherein the contact depth is determined by the height from the bottom of the test device of the sensing point that measures a pressure exceeding a nominal pressure.

29 . The method as recited in claim 27 , wherein the immersion depth is calculated by measuring how far down the test device has been pressed into the support surface.

30 . The method as recited in claim 22 , further comprising:
measuring the immersion depth that the test device has been pressed into support surface, wherein the envelopment parameter is further based on the immersion depth.

31 . The method as recited in claim 30 , wherein the envelopment parameter is an envelopment percentage (EP) determined by the following equation:
(2 *π*r *(contact depth))/(2 *π*r *(immersion depth))

32 . The method as recited in claim 31 , wherein the contact depth is determined by the distance to the highest sensing point that senses a pressure that is greater than a nominal value, and the immersion depth is determined by measuring the distance that the test device has been pressed into the patient support surface.

33 . The method as recited in claim 32 , wherein the distance that the test device has been pressed into the patient support surface is determined by a force displacement measuring device that automatically carries out the pressing step until a predetermined pressure is reached.

Assignees

• Hill Rom Services Inc

Inventors

• Sauser Frank
• Lachenbruch Charles A
• Tekulve Jon C

Classifications

• G01M99/007

  by applying a load, e.g. for resistance or wear testing (G01M99/001 takes precedence; testing the elasticity of structures G01M5/00) · CPC title

• G01L1/18

  using properties of piezo-resistive materials, i.e. materials of which the ohmic resistance varies according to changes in magnitude or direction of force applied to the material · CPC title

• G01M99/001 Primary

  Testing of furniture, e.g. seats or mattresses · CPC title

• A61G7/05

  Parts, details or accessories of beds (devices for prevention against falling out A47C21/08, A47D7/00 {; mattresses A47C27/00}) · CPC title

• G01N3/42

  by performing impressions under a steady load by indentors, e.g. sphere, pyramid (G01N3/54 takes precedence) · CPC title