U.S. patent application number 12/902115 was filed with the patent office on 2011-02-03 for sensors and systems for detecting environmental conditions or changes.
This patent application is currently assigned to VIGILAN, INCORPORATED. Invention is credited to Geoffrey J. Bunza, Steven W. Hudnut.
Application Number | 20110025510 12/902115 |
Document ID | / |
Family ID | 39541996 |
Filed Date | 2011-02-03 |
United States Patent
Application |
20110025510 |
Kind Code |
A1 |
Bunza; Geoffrey J. ; et
al. |
February 3, 2011 |
SENSORS AND SYSTEMS FOR DETECTING ENVIRONMENTAL CONDITIONS OR
CHANGES
Abstract
Sensors and systems for detecting predetermined environmental
conditions or changes may include a device capable of storing,
representing, or providing information, and a shield. The shield
may be disposed proximate the device. The shield may have a first
condition and a second condition. In the first condition the shield
is configured to prevent access to information stored in or on,
represented by or provided by the device. In the second condition
the shield is configured to permit access to information stored in
or on, represented by or provided by the device. The shield may be
configured to transition from the first condition to the second
condition when the shield is exposed to the predetermined
environmental condition.
Inventors: |
Bunza; Geoffrey J.;
(Beaverton, OR) ; Hudnut; Steven W.; (Beaverton,
OR) |
Correspondence
Address: |
Schwabe Williamson & Wyatt;PACWEST CENTER, SUITE 1900
1211 SW FIFTH AVENUE
PORTLAND
OR
97204
US
|
Assignee: |
VIGILAN, INCORPORATED
Wilsonville
OR
|
Family ID: |
39541996 |
Appl. No.: |
12/902115 |
Filed: |
October 11, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11615313 |
Dec 22, 2006 |
7812731 |
|
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12902115 |
|
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Current U.S.
Class: |
340/573.5 ;
340/10.1 |
Current CPC
Class: |
A61F 13/42 20130101;
A61F 5/48 20130101 |
Class at
Publication: |
340/573.5 ;
340/10.1 |
International
Class: |
G08B 23/00 20060101
G08B023/00; H04Q 5/22 20060101 H04Q005/22 |
Claims
1-52. (canceled)
53. A system for detecting a predetermined environmental condition,
wherein the system comprises: a device capable of providing
information, wherein the device comprises a passive RFID
transponder; a non-human interrogator configured to read
information provided by the device, wherein the interrogator
comprises an RFID reader configured to transmit power to the
passive RFID transponder, and the passive RFID transponder is
configured to transmit information to the RFID reader when the
passive RFID transponder receives power from the RFID reader; and a
shield, the shield having a first condition and a second condition,
wherein in the first condition the shield comprises a conductive
material configured to preclude at least one of the transmission of
power from the RFID reader to the passive RFID transponder and the
transmission of information from the passive RFID transponder to
the RFID reader, in the second condition the shield is configured
to permit the transmission of power from the RFID reader to the
passive RFID transponder and to permit the transmission of
information from the passive RFID transponder to the RFID reader,
and the shield is configured to transition from the first condition
to the second condition when the shield is exposed to the
predetermined environmental condition; and wherein the interrogator
indicates that the predetermined environmental condition exists
when the shield transitions to its second condition, the passive
RFID transponder receives power from the RFID reader and transmits
the information to the RFID reader, and the RFID reader receives
the information from the RFID transponder.
54. The system of claim 53, wherein the predetermined environmental
condition includes a fluid proximate at least one of the device and
the shield.
55. The system of claim 54, wherein the fluid includes a fluid
discharged by a patient during an incontinence event.
56. The system of claim 55, wherein at least one of the device and
the shield is disposed within a diaper such that the at least one
of the device and the shield is positioned proximate at least one
of a urine discharge orifice and a fecal discharge orifice of the
patient when the diaper is worn by the patient.
57. The system of claim 53, wherein in the first condition the
shield comprises a conductive sheet.
58. The system of claim 53, wherein in the first condition the
shield comprises a conductive mesh.
59. The system of claim 53, wherein the conductive material is
selected from the group consisting of conductive ink, conductive
paint, and conductive grease.
60. The system of claim 54, wherein at least a portion of the
shield is at least partially soluble in the fluid such that the
shield at least partially transitions from the first condition to
the second condition when the at least a portion of the shield at
least partially dissolves when the shield is exposed to the
fluid.
61. The system of claim 60, wherein the shield comprises a
shielding layer and an at least partially soluble carrier, the
shielding layer being at least partially disposed on the carrier,
when the shield is in the first condition the shielding layer is
configured to preclude the interrogator from reading information
provided by the device, the at least partially soluble carrier is
subject to breakdown when the carrier is exposed to the fluid, and
the breakdown of the carrier at least partially transitions the
shield from the first condition to the second condition.
62. The system of claim 53, wherein the shield comprises a
facilitator configured to at least partially enable the transition
of the shield from the first condition to the second condition when
the shield is exposed to the predetermined environmental
condition.
63. The system of claim 62, wherein the facilitator is configured
to increase in volume when exposed to the predetermined
environmental condition, the facilitator at least partially
encloses the device, the conductive material encloses at least a
portion of the device and at least a portion of the facilitator,
and the increase in volume of the facilitator when it is exposed to
the predetermined environmental condition induces stresses in the
conductive material sufficient to at least partially rupture the
conductive material.
64. The system of claim 63, wherein the conductive material
includes at least one stress enhancer, the shield is configured
such that the stress enhancer induces stress concentrations within
the conductive material when the facilitator increases in volume,
and the stress concentrations within the conductive material are
sufficient to at least partially enable rupture of the conductive
material.
65. The system of claim 62, wherein the shield further comprises a
carrier that is subject to breakdown when the shield is exposed to
the predetermined environmental condition, when the shield is in
the first condition the conductive material is deposited on and
supported by the carrier with the conductive material having a
first surface area, the facilitator includes a non-shielding
material disposed within the carrier, and the non-shielding
material has a second surface area greater than the first surface
area such that when the carrier breaks down upon exposure to the
predetermined environmental condition the shield transitions from
the first condition to the second condition as the conductive
material ruptures as it becomes deposited on the non-shielding
material of the facilitator.
66. The system of claim 53, wherein the information provided by the
device is stored on the device.
67. A method of detecting a predetermined environmental condition,
wherein the method comprises: providing a device capable of storing
information, wherein the device includes predetermined information
stored thereon; providing a non-human interrogator configured to
read at least some of the information stored on the device;
providing a shield, the shield having a first condition and a
second condition, wherein in the first condition the shield is
configured to preclude the interrogator from reading at least some
of the information stored on the device, in the second condition
the shield is configured to enable the interrogator to read at
least some of the information stored on the device, the shield is
provided in the first condition, the shield is configured to
transition from the first condition to the second condition when
the shield is exposed to the predetermined environmental condition,
the predetermined environmental condition includes a fluid
proximate at least one of the device and the shield, and at least a
portion of the shield is at least partially soluble in the fluid
such that the shield at least partially transitions from the first
condition to the second condition when the at least a portion of
the shield at least partially dissolves when the shield is exposed
to the fluid; exposing the shield to the predetermined
environmental condition such that the shield transitions from the
first condition to the second condition; reading with the
interrogator the predetermined information stored on the device;
and indicating that the predetermined environmental condition
exists in response to the interrogator reading the predetermined
information stored on the device; and wherein the shield comprises
a shielding layer and a facilitator, when the shield is in the
first condition the shielding layer is configured to preclude the
interrogator from reading at least some of the information stored
on the device, the facilitator is configured to at least partially
enable the transition of the shield from the first condition to the
second condition when the shield is exposed to the predetermined
environmental condition, the facilitator is configured to increase
in volume when exposed to the predetermined environmental
condition, the facilitator at least partially encloses the device,
the shielding layer encloses at least a portion of the device and
at least a portion of the facilitator, and the increase in volume
of the facilitator when it is exposed to the predetermined
environmental condition induces stresses in the shielding layer
sufficient to at least partially rupture the shielding layer.
68. A sensor for detecting a predetermined environmental condition,
comprising: a device capable of providing information, wherein the
device includes a passive RFID transponder configured to transmit
information to an external reader in response to an interrogation
signal from the external reader, the interrogation signal provides
operating power to the passive RFID transponder, and the device
provides information in a machine-readable format; and a shield
disposed proximate the device, the shield having a first condition
and a second condition, wherein in the first condition the shield
comprises a conductive material configured to preclude at least one
of the provision of operating power from the interrogation signal
to the passive RFID transponder and the transmission of information
from the passive RFID transponder to the external reader, in the
second condition the shield is configured to permit the provision
of operating power from the interrogation signal to the passive
RFID transponder and to permit the transmission of information from
the passive RFID transponder to the external reader, the shield is
configured to transition from the first condition to the second
condition when the shield is exposed to the predetermined
environmental condition, and the sensor detects the predetermined
environmental condition when the shield transitions to its second
condition, the passive RFID transponder receives operating power
from the interrogation signal, and the passive RFID transponder
transmits the information to the external reader.
69. The sensor of claim 68, wherein in the first condition the
shield comprises a conductive sheet.
70. The sensor of claim 68, wherein in the first condition the
shield comprises a conductive mesh.
71. The sensor of claim 68, wherein in the first condition at least
a portion of the shield is conductive ink, conductive paint, or
conductive grease.
72. The sensor of claim 68, wherein the device includes first and
second opposed major sides, and the-shield is disposed on at least
one of the first and second major sides of the device.
73. The sensor of claim 68, wherein the predetermined environmental
condition includes a predetermined fluid proximate at least one of
the device and the shield, and at least a portion of the shield is
at least partially soluble in the predetermined fluid such that the
shield at least partially transitions from the first condition to
the second condition when the at least a portion of the shield at
least partially dissolves when the shield is exposed to the
predetermined fluid.
74. The sensor of claim 73, wherein the shield comprises a
shielding layer and an at least partially soluble carrier, the
shielding layer is at least partially disposed on the carrier, when
the shield is in the first condition the shielding layer is
configured to prevent access to information provided by the device,
the at least partially soluble carrier is subject to breakdown when
the carrier is exposed to the predetermined fluid, and the
breakdown of the carrier at least partially transitions the shield
from the first condition to the second condition.
75. The sensor of claim 73, wherein the predetermined fluid
includes a fluid discharged by a patient during an incontinence
event.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation of and claims
priority to U.S. patent application Ser. No. 11/615,313, filed Dec.
22, 2006, the entire disclosure of which is hereby incorporated by
reference in its entirety.
FIELD OF THE DISCLOSURE
[0002] The present disclosure relates generally to sensors and
systems for detecting environmental conditions or changes.
BACKGROUND OF THE DISCLOSURE
[0003] The need to detect environmental conditions or changes
arises in many situations. For example, solid materials or liquids
may be introduced into or collect within an environment, parts or
components of a system may wear down or out, or the temperature,
pressure, chemical composition, atmosphere and/or some other
environmental condition may change. Regardless of whether such
changes or conditions may be beneficial, benign, harmful, desirable
and/or undesirable, an indication of the change or condition may be
useful. However, such changes or conditions may occur in locations
where access is difficult or even impossible, where access,
although possible or even simple, is undesirable for any number of
reasons, and/or where the environmental conditions or changes may
be hazardous to humans and/or equipment.
[0004] Nonexclusive illustrative examples of such environmental
conditions or changes may include detecting worn-out equipment or
materials, detecting leaks in containers carrying a fluid,
detecting the presence of fluids in undesirable locations,
detecting leaching (leaks of chemicals) in silver or gold mining
operations, detecting water or gas line bursts, or the like.
Additional examples may include the detection of temperature
changes, atmospheric changes (such as changes in pressure and/or
composition), the presence or absence of one or more materials,
and/or changes in other physical or environmental conditions such
as light or noise levels, or wear of mechanical devices, such as
brake pads or the like.
[0005] Additional nonexclusive illustrative examples of situations
in which it would be desirable to detecting environmental
conditions or changes arise in the field of health care. For
example, the detection of body fluids would be desirable for
assisting in the prevention of diaper rash, for potty training of
infants, and in curing enuretic youngsters, as well as for
detecting the leakage of blood or other fluids after surgery and
invasive diagnostic procedures. As a further nonexclusive
illustrative example, the detection of incontinence in chronically
bedridden persons, such as in the elder care field, would be useful
to facilitate better care for chronically bedridden persons.
[0006] For example, incontinence is a considerable problem in elder
health care. Elders often are immobile, and if these immobile
elders become incontinent and lose control of the evacuative
functions of urination or defecation and soil themselves, they may
be unable to help themselves or seek help. The urine or feces might
stay in place long enough for the elder to develop sores, which can
result in sickness, infection, and in the worse cases, even
death.
[0007] The current method of determining whether an elder has lost
control of his or her evacuative functions of urination or
defecation requires a caregiver to manually check the elder's
bedding and/or diaper. This is an arduous and demeaning process,
both for the caregiver and for the elder. Thus, there exists a need
for an easy and non-intrusive method of detecting incidents of
incontinence in elders.
[0008] Examples of sensors or systems for detecting predetermined
environmental conditions are disclosed in the following U.S. Pat.
Nos. 5,557,263; 5,570,082; 5,904,671; 6,294,997; 6,373,395;
6,583,722; 6,774,800; 6,846,994; 6,916,968; 7,053,781; 7,071,830;
and U.S. Patent Application Publication Nos. 2004/0061655;
2005/0012616; 2005/0285746. Examples of radio frequency
identification (RFID) devices and systems are disclosed in the
following U.S. Pat. Nos. 5,904,671; 6,294,997; 6,583,722;
6,774,800; 6,898,489; U.S. Patent Application Publication Nos.
2004/0061655; 2005/0012616; 2005/0285746; and in PCT Publication
Nos. WO 99/16019; WO 01/80174; WO 2004/016454; WO 2004/046762; WO
2005/006243; WO 2005/025554; WO 2005/076205; WO 2005/109308. The
complete disclosures of these and all other publications referenced
herein are incorporated by reference in their entirety for all
purposes.
SUMMARY OF THE DISCLOSURE
[0009] In one example, a system for detecting a predetermined
environmental condition may include a device capable of providing
information, a non-human interrogator, and a shield. The
interrogator may be configured to read information provided by the
device. The shield may have a first condition and a second
condition. In the first condition the shield may be configured to
preclude the interrogator from reading information provided by the
device. In the second condition the shield may be configured to
enable the interrogator to read information provided by the device.
The shield may be configured to transition from the first condition
to the second condition when the shield is exposed to the
predetermined environmental condition.
[0010] In one example, a system for detecting a predetermined
environmental condition may include a first device configured to
transmit a first signal, a second device configured to receive a
second signal, and a sensor. The sensor may include a third device
and a shield disposed proximate the third device. The third device,
responsive to receipt of the first signal by the third device, may
be configured to transmit the second signal. The shield may be
configured to preclude transmission of at least one of the first
signal to the third device and the second signal from the third
device. The efficacy of the shield may, upon exposure of the shield
to the predetermined environmental condition, be sufficiently
disrupted such that the disrupted shield may permit transmission of
at least one of the first signal to the third device and the second
signal from the third device.
[0011] In one example, a sensor for detecting a predetermined
environmental condition may include a device capable of providing
information and a shield disposed proximate the device. The shield
may have a first condition and a second condition. In the first
condition the shield may be configured to prevent access to
information provided by the device. In the second condition the
shield may be configured to permit access to information provided
by the device. The shield may be configured to transition from the
first condition to the second condition when the shield is exposed
to the predetermined environmental condition.
[0012] In one example, a method of detecting a predetermined
environmental condition may include providing a device capable of
storing information, which may include predetermined information
stored thereon, and a non-human interrogator, which may be
configured to read information stored on the device. The method may
further include providing a shield. The shield may have a first
condition and a second condition. In the first condition the shield
may be configured to preclude the interrogator from reading
information stored on the device. In the second condition the
shield may be configured to enable the interrogator to read
information stored on the device. The shield may be provided in the
first condition, and the shield may be configured to transition
from the first condition to the second condition when the shield is
exposed to the predetermined environmental condition. The method
may further include exposing the shield to the predetermined
environmental condition such that the shield may transition from
the first condition to the second condition; reading with the
interrogator the predetermined information stored on the device;
and indicating that the predetermined environmental condition
exists in response to the interrogator reading the predetermined
information stored on the device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a schematic view of an illustrative example of a
system for detecting environmental conditions or changes, with the
shield shown in a first or shielding condition.
[0014] FIG. 2 is a schematic view of the system of FIG. 1, with the
shield shown in a second or disrupted condition.
[0015] FIG. 3 is a schematic view of an illustrative example of an
RFID-based system for detecting environmental conditions or
changes, with the shield shown in a first or shielding
condition.
[0016] FIG. 4 is a schematic view of the RFID-based system of FIG.
3, with the shield shown in a second or disrupted condition.
[0017] FIG. 5 is a schematic cross-sectional view of an
illustrative example of a sensor that has separate shields.
[0018] FIG. 6 is a schematic cross-sectional view of an
illustrative example of a sensor that has a continuous shield.
[0019] FIG. 7 is a schematic cross-sectional view of an
illustrative example of a sensor that has a shield that includes a
carrier.
[0020] FIG. 8 is a schematic cross-sectional view of an
illustrative example of a sensor that has an expanding facilitator,
with the shield shown in a first or shielding condition.
[0021] FIG. 9 is a schematic cross-sectional view of the sensor of
FIG. 8, with the shield shown in a second or disrupted
condition.
[0022] FIG. 10 is a schematic cross-sectional view of an
illustrative example of a sensor that has a differential surface
area based facilitator, with the shield shown in a first or
shielding condition.
[0023] FIG. 11 is a schematic cross-sectional view of the sensor of
FIG. 10, with the shield shown in a second or disrupted
condition.
[0024] FIG. 12 is a schematic view of an illustrative example of
the components of a system for detecting the occurrence of an
incontinence event.
[0025] FIG. 13 is a schematic view of an illustrative example of
the components of an installed system for detecting the occurrence
of an incontinence event.
DETAILED DESCRIPTION
[0026] A nonexclusive illustrative example of a system 20 for
detecting environmental conditions or changes is shown generally at
20 in FIGS. 1 and 2. Unless otherwise specified, system 20 and its
various components may, but are not required to, contain at least
one of the structure, components, functionality, and/or variations
as the other systems for detecting environmental conditions or
changes described and/or illustrated herein. As shown in the
nonexclusive illustrative example presented in FIGS. 1 and 2,
system 20 includes a sensor 22, a corresponding non-human reader or
interrogator 24, and a communication path 26 extending between the
sensor 22 and the interrogator 24. When used in combination, sensor
22 and a corresponding appropriately configured interrogator 24
provide a system suitable for detecting at least one predetermined
environmental condition 30 or predetermined environmental change
32, as will be more fully described below.
[0027] Sensor 22 includes a device 36, which is capable of storing,
representing, or providing information 38 in a machine readable
format, and a shield 40, which may be disposed proximate device 36.
In some nonexclusive illustrative examples, the information 38 that
is represented or provided by device 36 may be stored in or on
device 36. As used herein, the storage of information refers to any
embodiment of data or information in and/or on a tangible object,
whether intrinsically, actively or intentionally.
[0028] Shield 40 is configured to prevent access to the information
38 stored in or on, represented by or provided by device 36, such
as by precluding interrogator 24 from reading the information 38
that is stored in or on, represented by or provided by device 36.
For example, shield 40 may at least partially disrupt, interfere
with, or interrupt communication path 26, as shown in the
schematically represented nonexclusive illustrative example
presented in FIG. 1.
[0029] A corresponding interrogator 24 for sensor 22 is one that is
configured to read or otherwise access the information 38 that is
stored in or on, represented by or provided by device 36 in a
particular machine readable format. If there is a communications
path 26 between interrogator 24 and device 36, interrogator 24
reads or otherwise accesses the information 38 stored in or on,
represented by or provided by device 36 when interrogator 24
receives a second or information signal 42 from device 36, such as
in response to a first or interrogation signal 44. In some
nonexclusive illustrative examples, information signal 42 may at
least partially include at least a portion of the information 38
that is stored in or on, represented by or provided by device 36.
In some nonexclusive illustrative examples, information signal 42
may at least partially include, or be based on or derived from, at
least a portion of interrogation signal 44 that has been at least
partially reflected or otherwise retransmitted from device 36. As
shown schematically in the nonexclusive illustrative example
presented in FIG. 2, interrogation signal 44 may be generated by
interrogator 24. However, in some nonexclusive illustrative
examples the interrogation signal 44 may be generated externally
from interrogator 24.
[0030] Information 38 may be stored in or on, represented by or
provided by device 36 in any suitable machine readable format. As
used herein, machine readable format refers to any format, system,
mechanism or manner of embodying, storing, representing or
providing data or information in a form that can be accessed, read,
sensed, interpreted or otherwise detected by the hardware and/or
software of an appropriately configured machine and/or computer.
The suitability of a particular machine readable format may be
determined based on the nature and suitability of the potentially
available communications paths 26 between sensor 22 and
interrogator 24. The nature and suitability of the available
communications paths 26 may depend on such factors as the quantum
of information stored in or on, represented by or provided by
device 36, the environment in which device 36 is or is expected to
be used, the physical proximity or distance between sensor 22 and
interrogator 24, or the like.
[0031] In some nonexclusive illustrative examples, when sensor 22
and interrogator 24 are optically visible relative to each other
such that there is an optical communication path 26 between sensor
22 and interrogator 24, information 38 may be stored, represented
or provided in an optically readable format such as a barcode or
any suitable type of machine readable characters or indicia. In
some nonexclusive illustrative examples, such as where physical
obstructions preclude an optical communication path 26 between
sensor 22 and interrogator 24, a magnetic or electromagnetic
communication path 26 may exist between sensor 22 and interrogator
24. When a magnetic communication path 26 is used, information 38
may be stored in or on, represented by or provided by a magnetic
label or marker and may be detected by an appropriate device such
as a Hall effect sensor. When an electromagnetic communication path
26 is used, information may be stored in or on, represented by or
provided by an RFID tag, the usage of which will be more fully
discussed below. Other nonexclusive illustrative examples of a
communication path 26 may be based on acoustics, such as the use of
surface acoustic wave devices, or any other suitable mechanism or
method that is capable of transmitting information. These and other
nonexclusive illustrative examples of communication paths are
discussed in Klaus Finkenzeller, RFID HANDBOOK (Rachel Waddington
trans., 2d ed. 2003), the complete disclosure of which is
incorporated by reference in its entirety for all purposes.
[0032] Information 38 may be any quantum of data that is
configurable to provide an indication of a detected predetermined
environmental condition 30 or predetermined environmental change
32. In some nonexclusive illustrative examples, information 38 may
be as simple as a single bit of data, which is sufficient to
provide an indication of the existence or absence of the particular
predetermined environmental condition 30 or predetermined
environmental change 32 that sensor 22 is configured to detect. For
example, device 36 may provide information 38 in the form of a
simple binary yes/no indication that device 36 is detectable or
otherwise readable by interrogator 24, which may correspond to the
existence or absence of the particular predetermined environmental
condition 30 or predetermined environmental change 32 that sensor
22 is configured to detect. In some nonexclusive illustrative
examples, such as in some nonexclusive illustrative examples where
information 38 is a simple binary yes/no indication that device 36
is detectable or otherwise readable by interrogator 24, the
information 38 may be limited to the existence of the device. In
some nonexclusive illustrative examples, such as where device 36 is
capable of storing more than a single bit of information,
information 38 may be sufficient to provide more than a simple
indication of the existence or occurrence of a particular
environmental condition or environmental change. For example,
information 38 may include any suitable combination of information
or data such as location, object or personal identification,
details regarding the particular environmental condition or
environmental change that exists or has occurred, timing
information regarding the duration of the detected environmental
condition, elapsed time since the occurrence of the environmental
change, or the like.
[0033] As shown in the nonexclusive illustrative example presented
in FIGS. 1 and 2, shield 40 may be in a shielding or first
condition 46 or in a disrupted or second condition 48. When shield
40 is in the first condition 46, shield 40 is configured to prevent
access to the information 38 stored in or on, represented by or
provided by device 36, such as by precluding interrogator 24 from
reading or otherwise accessing the information 38 that is stored in
or on, represented by or provided by device 36, such as by at least
partially disrupting, interfering with, or interrupting
communication path 26, as schematically shown in FIG. 1. For
example, when shield 40 is in the first condition 46, shield 40 may
at least partially preclude transmission of an interrogation signal
44 from interrogator 24 to device 36 and/or shield 40 may at least
partially preclude the transmission of an information signal 42,
which may at least partially contain or represent the information
38 stored in or on, represented by or provided by the device 36,
from device 36 to the interrogator 24.
[0034] The method or mechanism by which shield 40 disrupts,
interferes with, or interrupts communication path 26 varies with
the nature of the communication path 26, the interrogation signal
44, and information signal 42. For example, if the information 38
stored in or on, represented by or provided by device 36 is
optically readable by interrogator 24, then shield 40 might be at
least partially opaque to at least one of communication path 26,
interrogation signal 44, and information signal 42 when shield 40
is in the first condition 46. If the information 38 stored in or
on, represented by or provided by device 36 is magnetically
readable by interrogator 24, then shield 40 might be configured to
at least partially oppose the magnetic field of the interrogation
signal 44 generated by interrogator 24. For example, shield 40 may
include a metallic surface positioned adjacent device 36 such that
the eddy currents induced in the metallic surface at least
partially oppose the magnetic field of the interrogation signal 44.
If the information 38 stored in or on, represented by or provided
by device 36 is readable by interrogator 24 via electromagnetic
coupling between interrogator 24 and device 36, then shield 40 may
be configured to at least partially disrupt, interfere with, or
interrupt the electromagnetic field generated by interrogator 24,
such as where shield 40 acts as a radio frequency (RF) shield when
device 36 is an RFID transponder. The use and operational
principles of RF shields are known, and will not be discussed in
detail here.
[0035] When shield 40 is in the second condition 48, shield 40 is
configured to permit access to the information 38 stored in or on,
represented by or provided by device 36, such as by enabling or
permitting interrogator 24 to read or otherwise access the
information 38 that is stored in or on, represented by or provided
by device 36, such as by permitting communication path 26 to extend
from interrogator 24 to device 36, as schematically shown in FIG.
2. For example, when shield 40 is in the second condition 48, the
efficacy of shield 40 is sufficiently disrupted such that the
disrupted shield 40 permits transmission of the interrogation
signal 44 from interrogator 24 to device 36 and/or the disrupted
shield 40 permits transmission of the information signal 42 and/or
the information 38 stored in or on, represented by or provided by
the device 36 from device 36 to the interrogator 24.
[0036] System 20 detects environmental conditions or changes based
on the transition of shield 40 between the first condition 46 and
the second condition 48. In particular, as shown in the
nonexclusive illustrative example presented in FIGS. 1 and 2,
shield 40 is configured such that exposure to a predetermined
environmental condition 30 or predetermined environmental change 32
sufficiently disrupts shield 40 such that shield 40 transitions
from first condition 46 to second condition 48, which permits
transmission of the interrogation signal 44 from interrogator 24 to
device 36 and transmission of the information signal 42 and/or the
information 38 stored in or on, represented by or provided by the
device 36 from device 36 to the interrogator 24. When interrogator
24 receives information signal 42 and/or information 38 from device
36, system 20 provides an indication 54 of the predetermined
environmental condition 30 or predetermined environmental change
32. In some nonexclusive illustrative examples, the complexity of
indication 54 may vary with the complexity of information 38 stored
in or on, represented by or provided by device 36 as well as with
the ability of interrogator 24 to access information 38.
[0037] The particular predetermined environmental condition or
change to which a particular sensor is responsive may be determined
by selecting a shield that has a shielding efficacy that will be
disrupted when the shield is exposed to a particular condition or
change. As nonexclusive illustrative examples, a soluble shield may
be used when it is desired to detect the presence of a particular
solvent, a shield that degrades or otherwise changes properties at
certain temperatures may be used when it is desired to detect a
particular temperature, or a selectively positioned material having
low mechanical durability may be used when it is desired to detect
mechanical wear beyond a certain threshold. In some nonexclusive
illustrative examples, a shield may be selected based on its
nonresponsiveness to a particular predetermined environmental
condition or change whose detection is not desired. For example, if
it is desired to detect temperature variations, but not the
presence of a solvent, an insoluble shield that degrades at certain
temperatures may be used.
[0038] In some nonexclusive illustrative examples, disruption of
the shielding efficacy of a particular shield 40 or shielding
material when the shield 40 transitions from a first or shielding
condition 46 to a second or disrupted condition 48 may not
correspond to mechanical disruption or damage to the shield or
shielding material. In such an example, only the particular
physical property that corresponds to shielding efficacy needs to
be disrupted or altered. As a nonexclusive illustrative example,
shield 40 may include an environmentally responsive liquid crystal
material that is capable of at least partially disrupting,
interfering with, or interrupting communication path 26 when the
liquid crystal material is exposed to a predetermined environmental
condition 30 or predetermined environmental change 32. For example,
where the information 38 stored in or on, represented by or
provided by device 36 is optically readable by interrogator 24,
shield 40 might be an environmentally responsive liquid crystal
material that transitions from an at least partially opaque
condition to an at least partially transparent condition when
shield 40 transitions from first condition 46 to second condition
48 upon exposure to predetermined environmental condition 30 or
predetermined environmental change 32.
[0039] In some nonexclusive illustrative examples, system 20 may be
configured to only provide an indication that sensor 22 has been
exposed to predetermined environmental condition 30 or
predetermined environmental change 32. For example, shield 40 may
be configured such that exposure to predetermined environmental
condition 30 or predetermined environmental change 32 irreversibly
disrupts shield 40 such that shield 40 is permanently transitioned
from first condition 46 to second condition 48. In such an example,
sensor 22 may be considered a single-use sensor, which must be
replaced after use, or device 36 may be provided with a new shield
40 such the sensor 22 is at least partially reusable.
[0040] In some nonexclusive illustrative examples, system 20 may be
configured to provide an indication that sensor 22 has not been
exposed to predetermined environmental condition 30 or
predetermined environmental change 32. For example, system 20 may
be configured to provide an indication that sensor 22 has not been
exposed to predetermined environmental condition 30 or
predetermined environmental change 32 when interrogator 24 has not
received information signal 42 and/or information 38 from device 36
because shield 40 has not transitioned from first condition 46 to
second condition 48.
[0041] In some nonexclusive illustrative examples, system 20 may be
configured to provide an indication that sensor 22 is not currently
exposed to and/or has previously been exposed to predetermined
environmental condition 30 or predetermined environmental change
32. For example, shield 40 may be configured to transition from
second condition 48 to first condition 46 when shield 40 is no
longer exposed to predetermined environmental condition 30 or
predetermined environmental change 32, such as where shield 40 is
configured to reversibly transition between first condition 46 and
second condition 48. In such an example, system 20 may be
configured to provide an indication that sensor 22 is not currently
exposed to and/or has previously been exposed to predetermined
environmental condition 30 or predetermined environmental change 32
when interrogator 24 has previously received, but is not currently
receiving, information signal 42 and/or information 38 from device
36, such as where the efficacy of shield 40 is at least partially
restored when shield 40 is no longer exposed to predetermined
environmental condition 30 or predetermined environmental change
32.
[0042] A nonexclusive illustrative example of an RFID-based system
60 for detecting environmental conditions or changes is shown
generally at 60 in FIGS. 3 and 4. Unless otherwise specified,
system 60 and its various components may, but are not required to,
contain at least one of the structure, components, functionality,
and/or variations as the other systems for detecting environmental
conditions or changes described and/or illustrated herein. As shown
in the nonexclusive illustrative example presented in FIGS. 3 and
4, RFID-based system 60 may include an interrogator 24, a
corresponding sensor 22, and a shield 40, all of which are
configured for use within an RFID-based system.
[0043] Nonexclusive illustrative examples of RFID technologies and
systems that are suitable for use with the RFID-based system 60 may
be classified based on the type of coupling and/or communication
path 26 that exists between interrogator 24 and transponder or
device 36. Such nonexclusive illustrative examples may include
inductive coupling, electromagnetic backscatter coupling, close
coupling, electrical coupling, or the like. The use and operational
principles of such RFID technologies and systems are known, and
will not be discussed in detail here. Further discussion of RFID
technologies and systems may be found in Klaus Finkenzeller, RFID
HANDBOOK (Rachel Waddington trans., 2d ed. 2003), the complete
disclosure of which is incorporated by reference in its entirety
for all purposes
[0044] As shown in the nonexclusive illustrative example presented
in FIGS. 3 and 4, when used with an RFID-based system 60,
interrogator 24 includes an RFID reader 62 that is coupled to an
antenna 64. Antenna 64 is configured to transmit an interrogation
signal 44, such as when the RFID reader 62 generates an
electromagnetic field within an interrogation zone 66. In some
nonexclusive illustrative examples, RFID reader 62 may continuously
generate an electromagnetic field within interrogation zone 66.
RFID reader 62 is also configured to receive a second or
information signal 42, such as when an RFID-based sensor 22 is
disposed within interrogation zone 66.
[0045] As shown in the nonexclusive illustrative example presented
in FIGS. 3 and 4, when used with an RFID-based system 60, sensor 22
may include device 36, which may be included in the RFID
transponder 68. Device 36 may include a data carrier 70, such as a
microchip, which is coupled to a suitable coupling element 72, such
as a coil or an antenna. In some nonexclusive illustrative
examples, data carrier 70 may be conductively coupled to coupling
element 72. When the shield 40 is in the second condition 48, RFID
transponder 68 is configured to transmit information signal 42,
and/or the information 38 that is stored in or on, represented by
or provided by data carrier 70, to the RFID reader 62 of
interrogator 24 in response to RFID transponder 68 receiving an
interrogation signal 44 from interrogator 24. In some nonexclusive
illustrative examples, information signal 42 may at least partially
include, or be based on or derived from, at least a portion of
interrogation signal 44 that has been at least partially reflected
or otherwise retransmitted from device 36. For example, RFID
transponder 68 may be configured to reflect back to the
interrogator 24 at least a portion of the electromagnetic field
that corresponds to the interrogation signal 44. In some
nonexclusive illustrative examples, an information signal 42 based
on a reflected portion of interrogation signal 44 may provide a
simple binary yes/no indication that device 36 is detectable or
otherwise readable by interrogator 24, which may correspond to the
existence or absence of the particular predetermined environmental
condition 30 or predetermined environmental change 32 that sensor
22 is configured to detect. In some nonexclusive illustrative
examples, information signal 42 may at least partially carry
information 38 in the form of a modulation imposed on a reflected
portion of the interrogation signal 44, such as due to modulation
of the reflection cross-section of RFID transponder 68. When RFID
transponder 68 is passive, such as when RFID transponder 68 does
not include its own power source, the interrogation signal 44 that
is transmitted by interrogator 24 may provide operating power to
RFID transponder 68.
[0046] As shown in the nonexclusive illustrative example presented
in FIG. 3, when used with an RFID-based system 60, shield 40 may be
configured to preclude access to the information 38 stored in or
on, represented by or provided by device 36 when shield 40 is in
the first condition 46. For example, when shield 40 is in the first
condition 46, shield 40 at least partially disrupts, interferes
with, or interrupts RF-based communication path 26, which precludes
interrogator 24 from reading the information 38 that is stored in
or on, represented by or provided by device 36, such as by
precluding interrogator 24 from transmitting interrogation signal
44 or power to device 22, by precluding device 22 from receiving
interrogation signal 44 or power from interrogator 24, and/or by
precluding device 22 from transmitting information signal 42.
[0047] When used with an RFID-based system 60, shield 40 may
include any material or configuration capable of at least partially
disrupting, interfering with, or interrupting the RF-based
communication path 26 that exists between interrogator 24 and
device 36, such as between antenna 64 and coupling element 72. For
example, shield 40 may include a material capable of providing
electromagnetic or RF shielding, such as a conductive material
disposed between interrogator 24 and device 36, such as where
shield 40 includes a conductive material 74 that at least partially
surrounds device 36 and/or coupling element 72. In some
nonexclusive illustrative examples, conductive material 74 may at
least partially form a Faraday cage around device 36 and/or
coupling element 72. Nonexclusive illustrative examples of suitable
conductive materials 74 include conductive sheets, conductive
meshes, conductive greases, paints or ink, and the like.
Nonexclusive illustrative examples of conductive sheets may include
metal foils, such as gold or aluminum foils, carbon-based sheets,
such as those based on carbon fibers, and the like. Nonexclusive
illustrative examples of conductive meshes may include metallic
meshes, carbon-based meshes, and the like.
[0048] Schematic cross-sectional views of nonexclusive illustrative
examples of sensors 22 and shields 40 are shown in FIGS. 5-11.
Unless otherwise specified, each of the sensors 22 shown in FIGS.
5-11 may, but are not required to, contain at least one of the
structure, components, functionality, and/or variations as the
other sensors described and/or illustrated herein.
[0049] As shown in the nonexclusive illustrative example presented
in FIG. 5, shield 40 may completely surround device 36. For
example, as discussed above, shield 40 may be in the form of a
Faraday cage, such as where a conductive material 74 completely or
nearly completely surrounds device 36.
[0050] In some nonexclusive illustrative examples, shield 40 may
not completely surround device 36. For example, as shown in the
nonexclusive illustrative example presented in FIG. 6, sensor 22
may include a device 36 that has first and second opposed major
sides, faces or surfaces 80, 82. In such an example, shield 40
includes first and second portions 84, 86 of conductive material 74
that are disposed on the respective first and second opposed major
sides, faces or surfaces 80, 82 of device 36.
[0051] In some nonexclusive illustrative examples, the
predetermined environmental condition 30 or predetermined
environmental change 32 that system 20 is configured to detect may
include the presence of a predetermined fluid. In such an example,
at least a portion of shield 40 exhibits a response when exposed to
the fluid. For example, at least a portion of shield 40 may
chemically respond when exposed to the fluid, such as where at
least a portion of shield 40 is at least partially soluble or
otherwise subject to breakdown when exposed to the predetermined
fluid. Such an at least partially soluble shield 40 may be
configured to at least partially transition from the first or
shielding condition 46 to the second or disrupted condition 48 when
shield 40 is exposed to the predetermined fluid. For example, at
least a portion of an at least partially soluble shield may
dissolve when the shield is exposed to the predetermined fluid,
which may enable the transition of shield 40 from the first or
shielding condition 46 to the second or disrupted condition 48,
such as by sufficiently disrupting the efficacy of shield 40 such
that there is a communication path 26 extending from interrogator
24 to device 36, as suggested in FIG. 2. In some nonexclusive
illustrative examples, at least a portion of shield 40 may
otherwise respond when exposed to the predetermined fluid such as
by hardening, swelling, or the like.
[0052] In some nonexclusive illustrative examples, an at least
partially soluble shield 40 may include a shielding layer 90 that
is at least partially disposed on a carrier material 92, as shown
in FIG. 7. The shielding layer 90 may be configured such that, when
shield 40 is in the first condition 46, shielding layer 90 prevents
access to the information 38 stored in or on, represented by or
provided by device 36, such as by precluding interrogator 24 from
reading the information 38 that is stored in or on, represented by
or provided by device 36, such as by at least partially disrupting,
interfering with, or interrupting communication path 26, as
schematically shown in FIG. 1. For example, when shield 40 is in
the first condition 46, shielding layer 90 may at least partially
preclude transmission of an interrogation signal 44 from
interrogator 24 to device 36 and/or shielding layer 90 may at least
partially preclude the transmission of an information signal 42,
which may at least partially contain or represent the information
38 stored in or on, represented by or provided by the device 36,
from device 36 to the interrogator 24.
[0053] The use of a carrier material may permit or simplify the use
of particular shielding materials for shielding layer 90. For
example, such as in the case of an RFID-based system, shielding
layer 90 may be in the form of a conductive ink, grease or paint
that is printed or otherwise deposited onto the carrier material
92. In such an example, the structural integrity of shield 40 may
be provided by the carrier material 92 while the shielding efficacy
may be provided by the shielding layer 90. Even though the
shielding material itself may be relatively insoluble or otherwise
unresponsive to the presence of the predetermined environmental
condition 30, predetermined environmental change 32, or
predetermined fluid to which shield 40 is exposed, the carrier
material 92 itself may be at least partially soluble or otherwise
subject to breakdown when so exposed. Thus, because the structural
integrity of shield 40 is provided by the carrier material 92, the
breakdown of carrier material 92 may at least partially disrupt
shielding layer 90 and cause the transition of shield 40 from the
first or shielding condition 46 to the second or disrupted
condition 48 when shield 40 is exposed to predetermined
environmental condition 30, predetermined environmental change 32,
or the predetermined fluid.
[0054] When sensor 22 is configured for use in the detection of a
water-based fluid, examples of suitable materials for carrier
material 92 may include a water-soluble polymer such as polyvinyl
alcohol (PVA). Other water-soluble materials such as soluble rice
paper or the like may also be used.
[0055] In some nonexclusive illustrative examples, the at least
partially soluble shield 40 of sensor 22 may be configured such
that its solubility is at least partially temperature dependent.
For example, the water solubility of a water-soluble carrier
material 92 may be changed by changing the molecular weight of a
polymer utilized in the carrier material, such as by controlling
crosslinking of the polymer. By increasing crosslinking of the
polymer by a suitable amount, such as by a several-fold increase in
molecular weight, the water-soluble material may become
substantially insoluble in cold water, but still may remain soluble
in hot water.
[0056] In some nonexclusive illustrative examples where an
RFID-based system 60 is configured to detect the presence of a
predetermined fluid, shielding layer 90 may include a conductive
material that has its conductivity characteristics altered by
exposure to a predetermined substance or chemical. For example,
shielding layer 90 may include a conductive material whose
conductance is reduced or eliminated when the conductive material
is exposed to a predetermined fluid such as water or a fluid that
is discharged during an incontinence event, such as urine.
[0057] In addition to use with at least partially soluble shields,
a shielding layer 90 may be used in sensors configured to detect
mechanical changes. As a nonexclusive illustrative example, a
shielding layer 90, such as a metal foil in the case of an
RFID-based system 60, may be selectively placed within a component
that is subject to mechanical wear or chemically induced reductions
to structural volume. A nonexclusive illustrative example of such
use of a shielding layer 90 would be the inclusion of sensor 22
within a friction-inducing component, such as one tending to
decrease in thickness during use, such as a brake pad. By placing
sensor 22 at a predetermined depth in such a component, wear of the
component to the predetermined depth will expose the shielding
layer 90 of the sensor to wear. In such an example, use of a
shielding layer 90 that has little resistance to wear, such as a
metal foil in the case of an RFID-based system 60, will cause the
shield 40 to quickly transition from the first condition 46 to the
second condition 48 such that the system 60 will detect the wear of
the component to the predetermined depth.
[0058] In some nonexclusive illustrative examples, sensor 22 may
include a facilitator 96 configured to at least partially ensure,
stimulate, accelerate or otherwise enable the transition of shield
40 from the first or shielding condition 46 to the second or
disrupted condition 48 when sensor 22 and/or shield 40 is exposed
to predetermined environmental condition 30 or the predetermined
environmental change 32. Unless otherwise specified, each of the
facilitators 96 described herein may, but are not required to,
contain at least one of the structure, components, functionality,
and/or variations as the other facilitators described and/or
illustrated herein. The facilitator 96 may be any material,
structure, or mechanism capable of at least partially enabling the
transition of shield 40 from the first or shielding condition 46 to
the second or disrupted condition 48 when sensor 22 and/or shield
40 is exposed to the predetermined environmental condition 30 or
the predetermined environmental change 32. For example, by
expanding, contracting, and/or mechanically or chemically
interacting with the environment, facilitator 96 may enable the
transition of shield 40 from the first or shielding condition 46 to
the second or disrupted condition 48, such as by sufficiently
disrupting the efficacy of shield 40 such that a communication path
26 is enabled from interrogator 24 to device 36, as suggested in
FIG. 2. Nonexclusive illustrative examples of mechanisms by which
facilitator 96 may mechanically or chemically interact with the
environment may include melting, swelling, charring, dissolving, or
otherwise decomposing. In some nonexclusive illustrative examples,
facilitator 96 may be configured to ensure the transition of shield
40 from the first or shielding condition 46 to the second or
disrupted condition 48 when sensor 22 and/or shield 40 is exposed
to the predetermined environmental condition 30 or the
predetermined environmental change 32.
[0059] In some nonexclusive illustrative examples, the facilitator
96 may be at least partially enclosed by, or integral with, the
shielding layer 90 and/or carrier material 92. For example, as
suggested in the nonexclusive illustrative example presented in
FIG. 7, facilitator 96 may be at least partially disposed within,
or be a part of, carrier material 92. In such examples, facilitator
96 may be at least partially formed from a material that is
non-shielding relative to device 36. For example, when sensor 22 is
used in an RFID-based system 60, facilitator 96 may be fabricated
from a suitable non-conducting material such as a plastic, a glass,
a ceramic, or the like.
[0060] In some nonexclusive illustrative examples, facilitator 96
may be configured to expand or increase in volume when sensor 22 is
exposed to predetermined environmental condition 30 or
predetermined environmental change 32. For example, facilitator 96
may be configured to expand or increase in volume when shield 40 is
exposed to a predetermined fluid. In some nonexclusive illustrative
examples, facilitator 96 may include a carrier material 92 that at
least partially encloses device 36, with shielding layer 90
enclosing at least a portion of device 36 and at least a portion of
facilitator 96. A facilitator 96 that is configured to expand or
increase in volume when sensor 22 is exposed to predetermined
environmental condition 30 or the predetermined environmental
change 32 may be distinct from but within or enclosed by carrier
material 92, or the carrier material 92 may itself be configured to
expand or increase in volume when it is exposed to predetermined
environmental condition 30 or the predetermined environmental
change 32.
[0061] As shown in the nonexclusive illustrative example presented
in FIGS. 8 and 9, at least a portion of shield 40, such as at least
a portion of shielding layer 90, including any associated carrier
material 92, may enclose a facilitator 96 that is configured to
expand or increase in volume when sensor 22 is exposed to
predetermined environmental condition 30 or predetermined
environmental change 32. In such an example, when facilitator 96 is
in a first or unexpanded condition 100, shielding layer 90 is
sufficiently intact such that shield 40 is in the first or
shielding condition 46, as shown in FIG. 8. When sensor 22 and/or
facilitator 96 are exposed to predetermined environmental condition
30 or predetermined environmental change 32, such as to a
predetermined fluid, facilitator 96 increases in volume and
transitions from first condition 100 to a second or expanded
condition 102, as shown in FIG. 9. The increase in volume of
facilitator 96 when it is exposed to the predetermined
environmental condition or change induces stresses in the shielding
layer 90 that are sufficient to at least partially disrupt or
rupture the shielding layer 90, such as by formation of gaps 104 in
the shielding layer 90, which may cause the transition of shield 40
from the first or shielding condition 46 to the second or disrupted
condition 48. The presence of gaps 104 in the shielding layer 90
may alone be sufficient to cause the transition of shield 40 from
the first or shielding condition 46 to the second or disrupted
condition 48. However, in some nonexclusive illustrative examples,
the transition of shield 40 from the first or shielding condition
46 to the second or disrupted condition 48 may occur when the
fragments 106 of the shielding layer 90 slough off or otherwise
separate from sensor 22, as indicated in FIG. 9. In some
nonexclusive illustrative examples, environmental conditions may
assist or enhance the separation of fragments 106 from sensor 22.
For example, fluid flow, which may be turbulent, proximate sensor
22 may assist or enhance the separation of fragments 106 from
sensor 22.
[0062] Nonexclusive illustrative examples of suitable materials for
a facilitator 96 that is configured to expand or increase in volume
when sensor 22 is exposed to predetermined environmental condition
30 or the predetermined environmental change 32 include those
materials that provide an expansion large enough to induces
stresses in the shielding layer 90 that are sufficient to at least
partially disrupt or rupture the shielding layer 90. For example,
when used with a sensor 22 configured to detect the presence of a
fluid, facilitator may be in the form of a compressed sponge or
other material or object tending to expand in response to
absorption of the fluid. For example, facilitator 96 may be an
absorbent polymer, such as a high-gelling capacity crosslinked salt
of polyacrylic acid, such as sodium polyacrylate, which is a
crosslinked acrylic acid polymersodium salt.
[0063] In some nonexclusive illustrative examples of sensor 22,
facilitator 96 may be configured to expand or increase in volume
based on a chemical reaction. For example, facilitator 96 may be
configured to undergo a chemical reaction when sensor 22 and/or
facilitator 96 are exposed to the predetermined environmental
condition 30 or the predetermined environmental change 32. Such a
chemical reaction may be one that expansively produces a gas. For
example, when used with a sensor 22 configured to detect the
presence of a fluid, facilitator 96 may be configured to react with
the fluid in a chemical reaction that produces a gaseous product.
For example, facilitator 96 may include a mixture of citric acid
and sodium bicarbonate, which react vigorously to produce carbon
dioxide when mixed in a fluid such as water.
[0064] In some nonexclusive illustrative examples of sensor 22,
such as where sensor 22 includes an expanding facilitator 96 as
described above, shielding layer 90 may include at least one stress
enhancer 108, as indicated in FIG. 8. In such an example, shield 40
is configured such that at least one stress enhancer 108 induces
stress concentrations within the shielding layer 90 when the
expanding facilitator 96 increases in volume. Such stress
concentrations within the shielding layer 90 may be sufficient to
at least partially enable rupture of the shielding layer 90 and
enable the transition of shield 40 from the first or shielding
condition 46 to the second or disrupted condition 48. For example,
as indicated in FIG. 8, at least one stress enhancer 108 may be
provided on shielding layer 90 in the form of regions of reduced
thickness. Such regions of reduced thickness will lead to locally
higher tensile stresses when the shielding layer is stretched over
the expanded facilitator 96 when the facilitator is in the second
or expanded condition.
[0065] In some nonexclusive illustrative examples, facilitator 96
may be configured to mechanically ensure the disruption of
shielding layer 90 when sensor 22 and/or shield 40 are exposed to
predetermined environmental condition 30 or the predetermined
environmental change 32. For example, as schematically represented
in the nonexclusive illustrative example presented in FIGS. 10 and
11, facilitator 96 may include a plurality of ridges or projections
112. Ridges or projections 112 may be formed in any suitable
pattern. For example, ridges or projections 112 may include a
series of two-dimensional projections in the form of linear or
curvilinear ridges, which may intersect and/or be parallel. Ridges
or projections 112 may alternately or additionally include an array
or other distribution of a series of generally one-dimensional
projections such as generally pyramidal or conical shapes. Ridges
or projections 112 may be at least partially formed from a material
that is non-shielding relative to device 36. For example, when
sensor 22 is used in an RFID-based system 60, the ridges or
projections 112 may be fabricated from a suitable non-conducting
material such as a plastic, a glass, a ceramic, or the like.
[0066] A facilitator 96 that includes a plurality of ridges or
projections 112, may be used with a shield 40 that has a shielding
layer 90 deposited on a carrier material 92, such as where
shielding layer 90 includes a conductive ink or the like printed
onto carrier material 92, as schematically represented in FIG. 10.
As discussed above, the structural integrity of such a shield may
be provided by the carrier material 92 while the shielding efficacy
may be provided by the shielding layer 90. For example, the
thicknesses of shielding layer 90 may be significantly larger than
the thickness of carrier material 92. By way of nonexclusive
illustrative example, carrier material 92 may have a thickness of
approximately 0.003 inches (76 .mu.m) while shielding layer 90 may
have a thickness of approximately 0.0005 inches (12 .mu.m).
[0067] Although the at least partial dissolution or breakdown of
carrier material 92 may disrupt shielding layer 90 to a sufficient
extent as to cause shield 40 to transition from the first or
shielding condition 46 to the second or disrupted condition 48 when
shield 40 is exposed to predetermined environmental condition 30 or
predetermined environmental change 32, the inclusion of a
facilitator 96 that includes a plurality of ridges or projections
112 may ensure that shielding layer 90 is sufficiently disrupted to
transition shield 40 to the second or disrupted condition 48. In
particular, the plurality of ridges or projections 112 may prevent
shielding layer 90 from depositing or decaling itself onto the
surfaces 114 of device 36 subsequent to the dissolution or
breakdown of carrier material 92. As may be observed from the
schematic representation of the nonexclusive illustrative example
presented in FIG. 10, the surface area of the exterior surfaces 116
of the plurality of ridges or projections 112 is significantly
larger than the surface area of the shielding layer 90 due to the
fact that shielding layer 90 passes across the valleys 118 between
the ridges or projections 112. Thus, in the event that shielding
layer 90 tends to deposit or decal itself onto the plurality of
ridges or projections 112 upon the dissolution or breakdown of
carrier material 92, shielding layer 90 may be disrupted into
fragments 106 that are separated by gaps 104. Shielding layer 90
may be disrupted into fragments 106 because shielding layer 90
lacks sufficient material to deposit or decal itself over the
entirety of the surfaces 116 of the peaks 120 and valleys 118 of
the ridges or projections 112 without rupturing, as schematically
represented in FIG. 11. By way of nonexclusive illustrative
example, the depths of the valleys 118 between the ridges or
projections 112 may be approximately 0.063 inches (1.6 mm or 1600
.mu.m).
[0068] A nonexclusive illustrative example of a system for
detecting the occurrence of an incontinence event is shown
generally at 130 in FIG. 12. Unless otherwise specified, system 130
and its various components may, but are not required to, contain at
least one of the structure, components, functionality, and/or
variations described and/or illustrated herein. As discussed above,
system 130 is based on at least one sensor 22 that is paired with
at least one corresponding interrogator 24, which is configured to
read information that is stored in or on, represented by, or
provided by sensor 22 when its shield 40 is disrupted. System 130
may include a diaper 132 and an interrogator 24.
[0069] As shown in the nonexclusive illustrative example presented
in FIG. 12, diaper 132 may include at least one sensor 22. The
sensors 22 may be disposed within diaper 132 such that the sensors
are suitably located to detect a fluid, such as urine or fecal
matter, discharged by a patient during an incontinence event. For
example, at least one sensor 22 may be located proximate a frontal
region 134 of diaper 132, at least one sensor 22 may be located
proximate a posterior region 136 of diaper 132, and/or at least one
sensor 22 may be located proximate a lower region 138 of diaper
132. In some nonexclusive examples, diaper 132 may be configured
such that, when diaper 132 is worn by a patient, at least one
sensor 22, and/or its corresponding shield 40, is located proximate
a urine discharge orifice and/or proximate a fecal discharge
orifice of the patient.
[0070] During operation of system 130, a patient may be fitted with
a diaper 132 that includes at least one suitably located sensor 22.
The patient may be located such that the patient, or at least
diaper 132, is positioned within the interrogation zone 66 of
interrogator 24. In some nonexclusive illustrative examples, the
interrogator 24 may continuously transmit an interrogation signal
44 into the interrogation zone 66. For example, if system 130 is
RFID-based, interrogator 24 may continuously generate an
electromagnetic field within interrogation zone 66. When the
patient experiences an incontinence event, the discharged fluids
may be collected in diaper 132 proximate at least one of the
sensors 22 and/or its corresponding shield 40. The presence of the
discharged fluid proximate the sensor 22 and/or its shield 40, may
disrupt the shield 40 such that, responsive to the interrogation
signal 44, the sensor 22 may transmit an information signal 42 to
the interrogator 24, which may provide an indication 140 of the
occurrence of the incontinence event. In some nonexclusive
illustrative examples, information signal 42 may provide an
indication of the type of incontinence event or it may provide
identification and location information.
[0071] A nonexclusive illustrative example of an installed system
for detecting the occurrence of an incontinence event is shown
generally at 150 in FIG. 12. Unless otherwise specified, system 150
and its various components may, but are not required to, contain at
least one of the structure, components, functionality, and/or
variations as the other systems for detecting the occurrence of an
incontinence event described and/or illustrated herein. System 150
may be installed in a fixed location such as a hospital or nursing
home room 152.
[0072] System 150 may include at least one interrogator 24 mounted
or otherwise disposed within the room 152. In some nonexclusive
illustrative examples of system 150, at least one interrogator 24
may be configured to continuously transmit an interrogation signal
44 into a fixed interrogation zone 66, such as a zone generally
surrounding the bed 154 in which the individual receiving care or
patient 156 is located. For example, at least one interrogator 24
may be fixedly mounted within the room 152 or the bed 154. In some
nonexclusive illustrative examples, system 150 may be RFID-based,
in which case interrogator 24 may continuously generate an
electromagnetic field within interrogation zone 66.
[0073] In some nonexclusive illustrative examples of system 150, at
least one interrogator 24 may be portable, such as to permit usage
outside a fixed interrogation zone. In some nonexclusive
illustrative examples, at least one interrogator 24 may be fixedly
mounted to bed 154.
[0074] In some nonexclusive illustrative examples of system 150, at
least one sensor 22 may be mounted within the room 152, such as in
a piece of furniture or other location in which the patient 156 may
experience an incontinence event. For example, as shown in the
nonexclusive illustrative example presented in FIG. 13, at least
one sensor 22 may be mounted in bed 154, such as within the
mattress or sheets.
[0075] As shown in the nonexclusive illustrative example presented
in FIG. 13, system 150 may include at least one monitoring station
158. Monitoring station 158 may be located at any suitable location
where it can receive an indication 140 from at least one of the
interrogators 24 that the patient 156 has experienced an
incontinence event. Monitoring station 158 may be configured to
notify an appropriate party, such as an attendant or nurse, that
the patient 156 has experienced an incontinence event. The use of
system 150 to provide notification that a patient 156 has
experienced an incontinence event may permit an attendant or nurse
to become aware of the occurrence of an incontinence event without
having to manually examine the patient, which may permit enhanced
patient privacy or dignity.
[0076] As a nonexclusive illustrative example of operation of a
system for detecting environmental conditions or changes, a sensor
such as a device capable of storing, representing, or providing
information may be provided. In some nonexclusive illustrative
examples, the device may be provided with predetermined information
stored thereon. The predetermined information may include any
suitable combination of information such as location, object or
personal identification, details regarding the particular
environmental condition or environmental change that exists or has
occurred, timing information regarding the duration of the detected
environmental condition, elapsed time since the occurrence of the
environmental change, or the like.
[0077] A non-human interrogator that is configured to read
information stored in or on, represented by or provided by the
device may be provided. In the case of an RFID-based system for
detecting environmental conditions or changes, the interrogator may
continuously generate an electromagnetic field within an
interrogation zone.
[0078] A shield that has a first condition and a second condition
may be provided with the shield provided in the first condition. In
some nonexclusive illustrative examples, the shield may be provided
proximate the device. In the first condition the shield is
configured to preclude the interrogator from reading information
stored in or on, represented by or provided by the device. In the
second condition the shield is configured to enable the
interrogator to read information stored in or on, represented by or
provided by the device. The shield is configured to transition from
the first condition to the second condition when the shield is
exposed to a predetermined environmental condition or change, such
as the presence of a predetermined fluid.
[0079] During operation of the system, the sensor may be placed
into an environment in which there is an interest in detecting
environmental conditions or changes, such as a predetermined
environmental condition or change, such as the presence of a
unexpected and/or undesirable material, such as the presence of an
unexpected and/or undesirable fluid. The interrogator may be
positioned such that, if it could read the information stored in or
on, represented by or provided by the device, it would read the
information stored in or on, represented by or provided by the
device. The interrogator will attempt to read the information
stored in or on, represented by or provided by the device. In the
case of an RFID-based system for detecting environmental conditions
or changes, the interrogator may continuously attempt to read the
information stored in or on, represented by or provided by a device
located within the interrogation zone. The failure of the
interrogator to read the information stored in or on, represented
by or provided by the device may be used as an indication that the
shield is in the first condition because the predetermined
environmental condition or change has not occurred and/or is not
currently occurring.
[0080] When the shield and/or the sensor are exposed to the
predetermined environmental condition or change, the shield will
transition from the first condition to the second condition. Once
the shield is in the second condition, the interrogator will be
able to read the information stored in or on, represented by or
provided by the device, and the interrogator will read the
information that is stored in or on, represented by or provided by
the device. Based on the information read by the interrogator from
the device, the interrogator may provide an indication that the
predetermined environmental condition or change exists and/or has
occurred.
[0081] In some nonexclusive illustrative examples of using the
system for detecting environmental conditions or changes where the
system is being used to provide an indication that a person has
experienced an incontinence event, the method may include
positioning at least one of the sensor and/or the shield proximate
at least one of a urine discharge orifice and/or a fecal discharge
orifice of a patient. In such an example, the predetermined fluid
includes a fluid discharged by the patient during an incontinence
event, such as urine or fecal matter.
[0082] It is believed that the disclosure set forth herein
encompasses multiple distinct inventions with independent utility.
While each of these inventions has been disclosed in its preferred
form, the specific embodiments thereof as disclosed and illustrated
herein are not to be considered in a limiting sense as numerous
variations are possible. The subject matter of the disclosure
includes all novel and non-obvious combinations and subcombinations
of the various elements, features, functions and/or properties
disclosed herein. Similarly, where the claims recite "a" or "a
first" element or the equivalent thereof, such claims should be
understood to include incorporation of one or more such elements,
neither requiring nor excluding two or more such elements.
[0083] It is believed that the following claims particularly point
out certain combinations and subcombinations that are directed to
one of the disclosed inventions and are novel and non-obvious.
Inventions embodied in other combinations and subcombinations of
features, functions, elements and/or properties may be claimed
through amendment of the present claims or presentation of new
claims in this or a related application. Such amended or new
claims, whether they are directed to a different invention or
directed to the same invention, whether different, broader,
narrower or equal in scope to the original claims, are also
regarded as included within the subject matter of the inventions of
the present disclosure.
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