U.S. patent application number 12/456221 was filed with the patent office on 2010-02-18 for physiological monitoring garment.
Invention is credited to Jeremy Bowman, Brian Farrell, Joseph Ting.
Application Number | 20100041974 12/456221 |
Document ID | / |
Family ID | 34421486 |
Filed Date | 2010-02-18 |
United States Patent
Application |
20100041974 |
Kind Code |
A1 |
Ting; Joseph ; et
al. |
February 18, 2010 |
Physiological monitoring garment
Abstract
A physiological monitoring garment includes a fabric portion. At
least one elongate stretchable textile data/power bus is disposed
the fabric portion. The elongate stretchable textile data/power bus
includes a plurality of integral conductors, woven, knitted, or
braided along the length thereof. One or more sensors are connected
to the elongate stretchable textile data/power bus.
Inventors: |
Ting; Joseph; (Acton,
MA) ; Farrell; Brian; (Quincy, MA) ; Bowman;
Jeremy; (Arlington, MA) |
Correspondence
Address: |
Iandiorio Teska & Coleman
260 Bear Hill Road
Waltham
MA
02451
US
|
Family ID: |
34421486 |
Appl. No.: |
12/456221 |
Filed: |
June 12, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10922336 |
Aug 20, 2004 |
7559902 |
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12456221 |
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60497423 |
Aug 22, 2003 |
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Current U.S.
Class: |
600/388 ;
600/300 |
Current CPC
Class: |
A41D 13/1281 20130101;
A61B 5/11 20130101; A41D 1/002 20130101; A61B 5/0816 20130101; A61B
5/01 20130101; A61B 5/318 20210101; A61B 5/296 20210101; A61B
5/6804 20130101; A61B 5/6831 20130101; A61B 5/25 20210101; G16H
40/63 20180101; A61B 5/389 20210101; A61B 5/291 20210101 |
Class at
Publication: |
600/388 ;
600/300 |
International
Class: |
A61B 5/04 20060101
A61B005/04; A61B 5/00 20060101 A61B005/00 |
Goverment Interests
GOVERNMENT RIGHTS
[0002] This invention was made with U.S. Government support under
Contract No. Contract No. DAMD17-03-C-0022 awarded by the U.S. Army
Medical Material Command. The Government may have certain rights in
the subject invention.
Claims
1. A physiological monitoring garment comprising: a fabric portion;
at least one elongate stretchable textile data/power bus disposed
on the fabric portion, the elongate stretchable textile data/power
bus including a plurality of integral conductors, woven, knitted,
or braided along the length thereof; and one or more sensors
connected to the elongate stretchable textile data/power bus.
2. The physiological monitoring garment of claim 1 in which at
least one of said plurality of integral conductors extends
externally from said textile/data power bus for connecting said one
or more sensors thereto.
3. The physiological monitoring garment of claim 1 in which the
fabric portion is an elastic fabric portion.
4. The physiological monitoring garment of claim 1 in which the
plurality of conductors are woven, knitted, or braided in a strain
relief pattern.
5. The physiological monitoring garment of claim 4 in which the
plurality of conductors include conductors for data transfer,
conductors for power transfer, and conductors structured and
arranged to form an electric shield for reducing noise.
6. The physiological monitoring garment of claim 4 in which a
coating of conductive material is disposed on the elongate
stretchable textile data/power bus to form an electrical shield for
reducing noise.
7. The physiological monitoring garment of claim 4 in which said
strain relief pattern is out of the plane of said stretchable
data/power bus.
8. The physiological monitoring garment of claim 4 in which said
strain relief pattern is in the plane of said stretchable
data/power bus.
9. The physiological monitoring garment of claim 1 in which
connectors connect the one or more sensors to the elongate
stretchable textile data/power bus.
10. The physiological monitoring device of claim 9 in which the
connectors are insulation displacement connectors.
11. The physiological monitoring garment of claim 1 in which a
sensor includes a respiration monitoring device.
12. The physiological monitoring garment of claim 11 in which said
respiration monitoring device includes: at least a first elongate
stretchable textile member, at least first and second conductive
components associated with said textile member, and threads of said
textile member providing dielectric separation between the at least
first and second conductive components so that the expansion and
contraction of the textile member results in a change in the
spacing between the first and second conductive components for
measuring change in capacitance.
13. The physiological monitoring garment of claim 12 in which the
first conductive component includes woven, knitted, or braided
conductive threads integral with said first textile member.
14. The physiological monitoring garment of claim 13 in which there
are a plurality of elongate stretchable textile members adjacent
each other and each includes integral woven, knitted, or braided
conductive threads.
15. The physiological monitoring garment of claim 12 in which said
respiration monitoring device is disposed in or on said garment
proximate said data/power bus.
16. The physiological monitoring garment of claim 1 in which a said
sensor includes: a flexible circuit board configured as an
electrode, a conductive portion on one surface of said flexible
circuit board, and a dielectric material on said conductive
portion.
17. The physiological monitoring garment of claim 16 in which an
opposing surface of said flexible circuit board includes signal
conditioning circuitry.
18. The physiological monitoring garment of claim 16 in which said
flexible circuit board is connected to a second flexible circuit
board including signal conditioning circuitry.
19. The physiological monitoring garment of claim 17 further
including conductive traces interconnecting said conductive portion
with said signal conditioning circuitry.
20. The physiological monitoring garment of claim 16 in which said
conductive portion is a conductive foil laminated on said flexible
circuit board.
21. The physiological monitoring garment of claim 16 in which said
conductive portion is conductive material sputtered or plated on
said flexible circuit board.
22. The physiological monitoring garment of claim 16 in which said
dielectric material is material sputtered, laminated, evaporated,
or spun onto said conductive portion.
23. The physiological monitoring garment of claim 16 in which the
sensor further includes an insulating edge for preventing short
circuits.
24. The physiological monitoring garment of claim 16 in which the
flexible circuit board is configured to include at least two
electrodes.
25. The physiological monitoring garment of claim 24 in which the
two electrodes each include signal conditioning circuitry.
26. A physiological monitoring garment comprising: a first fabric
portion; a second fabric portion; an elongate stretchable textile
data/power bus between the first fabric portion and the second
fabric portion, the elongate stretchable textile data/power bus
including a plurality of integral conductors, woven, knitted, or
braided along the length thereof; and one or more sensors connected
to the elongate stretchable textile data/power bus.
27. A physiological monitoring device comprising: an elongate
stretchable textile data/power bus including a plurality of
integral conductors, woven, knitted, or braided along the length
thereof; and one or more sensors connected to the elongate
stretchable textile data/power bus.
28. A sensor for an individual comprising: a circuit board
configured as a bioelectrode, a conductive portion on one surface
of said circuit board, and a dielectric material on said conductive
portion electrically isolating said bioelectrode from the
individual.
29. The sensor of claim 28 in which an opposing surface of said
circuit board includes signal conditioning circuitry.
30. The sensor of claim 28 in which said circuit board is connected
to a second circuit board including signal conditioning
circuitry.
31. The sensor of claim 29 further including conductive traces
interconnecting said conductive portion with said signal
conditioning circuitry.
32. The sensor of claim 28 in which said conductive portion is a
conductive foil laminated on said circuit board.
33. The sensor of claim 28 in which said conductive portion is
conductive material sputtered or plated on said circuit board.
34. The sensor of claim 28 in which said dielectric material is
material sputtered, laminated, evaporated, or spun onto said
conductive portion.
35. The sensor of claim 28 in which the circuit board is
flexible.
36. The sensor of claim 28 in which the circuit board is rigid.
37. The sensor of claim 28 in which said sensor monitors
biopotentials.
38. The sensor of claim 37 in which the biopotentials monitored by
said sensor include at least one of ECG, EMG, EEG and EOG.
39. A sensor comprising: a circuit board configured as a
bioelectrode, a conductive portion on one surface of said circuit
board, and a dielectric material on said conductive portion whereby
said sensor is an electrostatic sensor.
Description
RELATED APPLICATIONS
[0001] This application is a continuation of prior U.S. patent
application Ser. No. 10/922,336 filed Aug. 20, 2004 which claims
the benefit of and priority to U.S. Provisional Patent Application
Ser. No. 60/497,423 filed Aug. 22, 2003, and each application is
incorporated herein by reference.
FIELD OF THE INVENTION
[0003] This invention relates to "wearable electronics", "wearable
computers", "smart fabrics" and the like and more particularly a
physiological monitoring garment including at least an integrated
data/power bus. This invention also relates to a respiration
monitoring device and sensors useful in connection with the
physiological monitoring garment or other physiological sensor
systems.
BACKGROUND OF THE INVENTION
[0004] The idea of "wearable computers" and electronic circuits
built entirely out of textiles to distribute data and power and
designed to perform functions such as touch sensing was first fully
described in a disclosure called "Smart Fabric, or Washable
Computing" by E. Rehmi Post and Maggie Orth of the MIT Media
Laboratory available on the Internet at
http:/www.media.mit.edu%7EREHMI/fabric/index.html and also on pp.
167-168 of the Digest of Papers of the First IEEE International
Symposium on Wearable Computers, Oct. 13-14, 1997 held in
Cambridge, Mass.
[0005] Prior to the applicant's invention described herein,
electrical or electronic components were sometimes fastened to
articles of clothing or placed in pouches or pockets. Individual
wires between these components were then fastened to the outside of
the clothing or disposed partially or wholly in seams and the like.
In this way, a soldier could "wear" a radio and a computer and/or
global positioning satellite system. Consumers, in turn, could, for
example, "wear" a cellular telephone connected to a headset or a
speaker and/or microphone located on the collar of a jacket.
[0006] The problem with this design is that the wires are separate
from the textile material of the clothing. As a result, the wires
are unsightly and uncomfortable, do not wear well, can catch and
tangle on objects, reduce mobility, add weight, are not washable,
and are not resistant to corrosion. In general, such a design is
not very robust.
[0007] Therefore, those skilled in the art sought to integrate the
electronic circuits and data and power conductors within the
textile of the articles of clothing themselves. See the MIT
disclosure referred to above and incorporated herein by this
reference. In the MIT reference, metallic yarn forms the weft of
the fabric and, running in the other direction, plain silk thread
forms the warp of the fabric. Surface mount light emitting diodes
(LED's), crystal piezo transducers, and other surface mount
components are then soldered directly onto the metallic yarn.
[0008] But, since the metallic yarn only runs in one direction,
communications and interconnections between the electronic devices
can only take place in that direction. Worse, the individual
metallic yarns which do not electrically interconnect two
components must be cut to provide electrical isolation for the
individual metallic yarns which do electrically interconnect two
components. This design thus raises serious design concerns, namely
manufacturability, shielding, and electrical interference.
Moreover, the fabric including the soldered-on electronic
components is delicate, cannot be washed, has no stretch, and is
uncomfortable to wear. Finally, if the fabric is folded back on
itself, an electrical short will occur. Thus, special insulative
coatings or substrates must be used which further render the fabric
uncomfortable to wear.
[0009] Others have designed textile fabrics with conductive fibers
for electrically interconnecting two electronic components. See
U.S. Pat. Nos. 6,080,690 and 5,906,004 incorporated herein by this
reference. Again, the main idea is that the whole garment is made
of this special fabric. As such, a sensor can be electrically
connected to a controller right on the garment. Still, routing of
the data or power between the devices is limited without extensive
formation of electrical junctions in the fabric--a very cumbersome
manufacturing process. In addition, such garments are also
uncomfortable and cannot withstand repeated wash cycles. See also
U.S. Pat. No. 3,414,666 incorporated herein by this reference.
[0010] Commonly owned U.S. Pat. No. 6,727,197, incorporated herein
by this reference, discloses designs of textile materials with
integrated data or power buses which are simple to manufacture,
pleasing in appearance, comfortable, washable, which wear well,
which do not add significant weight, which are corrosion resistant,
which do not impede mobility, which exhibit high fatigue strengths,
and which also properly meet or exceed the electrical interface and
shielding requirements of the specific application, be it military
or consumer-based.
[0011] The present invention more particularly relates to
physiological sensing systems as they pertain to wearable
electronics. Such systems (e.g., garments) are useful for
ambulatory/home monitoring (prophylaxis, diagnosis and/or
treatment), in-hospital post-operative monitoring, athletic
performance training, infant respiration monitoring for the
detection of sudden infant death syndrome, and the like. There has
been a lot of activity in this field and in one example it is
proposed to include conductive electrocardiogram electrodes and
inductive plethysmographic sensors sewn, embroidered, embedded or
otherwise attached to a garment such as a shirt with an adhesive.
See, for example, U.S. Pat. No. 6,047,203 incorporated herein by
this reference.
[0012] To date, however, the applicants are unaware of a marketable
system which employs low profile sensors held in position against
the body throughout a typical range of movements for mechanical and
electrical coupling. And, although the prior art teaches garments
with integral electrodes and sensors, there is a general failure in
the art to consider a non-intrusive, conformable, comfortable
integrated data/power bus for providing power to the sensors and
electrodes (as required) and for routing sensor/electrode signals
to the appropriate processing and/or transmission circuitry.
[0013] Any viable system will probably be required to include
physiological sensors, electrodes, a textile data/power bus with
the appropriate connectors and conductors, sensor
conditioning/processing capability, and a power source. Optional
elements could be body worn or externally located for analysis and
warning features and also include a communication system to support
data transmission. A preferred system would include a textile-based
elastic body conforming garment including textile fibers formed
using knitting, weaving, or braiding techniques and incorporating
elastic fiber elements such as Lycra. The sensors would include one
or more physiological sensors such as ECG or R-wave sensors, EMG
sensors, a respiration sensor, and perhaps skin temperature and
body position and motion sensors. Preferably, the sensors would be
integral to the garment and operate without the requirement of any
user manipulation. Gels and adhesives would preferably not be
required. The sensors and their associated electronics should be
modular and detachable from the garment for replacement or
maintenance. The data/power bus should also be integrated into the
garment textile structure to minimize intrusiveness and to maximize
user comfort and convenience. The data/power bus should also be
transparent to the user and require minimal user manipulation after
the system has been donned. The garment should be moisture and
temperature resistant for operation under typical environmental
conditions, and could include a combination of reusable washable
elements and, in some examples, disposable elements. Integral
connectors would allow the sensors and electronics to be detached
for washing and the remaining garment should survive numerous wash
cycles. In another possibility, the sensors and electronics of the
system are permanently attached to the garment if it can be
manufactured at such a cost that it can be disposed of.
[0014] A review of the prior art reveals no system which meets the
above criteria for a viable physiological monitoring garment.
BRIEF SUMMARY OF THE INVENTION
[0015] It is therefore an object of this invention to provide an
improved physiological monitoring garment.
[0016] It is a further object of this invention to provide a more
comfortable and more robust physiological monitoring garment.
[0017] It is a further object of this invention to provide a
physiological monitoring garment that does not impede mobility and
is simple to manufacture.
[0018] It is a further object of this invention to provide a
physiological monitoring garment that is useful for numerous
applications such as ambulatory home and outpatient monitoring and
athletic performance training.
[0019] It is a further object of this invention to provide a
physiological monitoring garment including an integrated
stretchable power/data bus for use with a variety of sensors.
[0020] It is a further object of this invention to provide an
improved flexible low profile sensor, as well as to provide an
improved respiration monitoring device, each of which may be used
in conjunction with the improved physiological monitoring
garment.
[0021] The invention results from the realization that an improved
physiological monitoring garment can be achieved with an elongate
stretchable textile data/power bus disposed in an elastic fabric
having one or more sensors connected to it. The invention results
from the further realization that an improved sensor useful with
the physiological monitoring garment can be achieved with a
flexible circuit board configured as an electrode with a conductive
portion on one surface and a dielectric material on the conductive
portion. The flexibility helps prevent bridging and capacitive
coupling avoids the necessity of conductive gels or adhesives. The
invention also results from the further realization that an
improved respiration monitoring device useful with the
physiological monitoring garment can be achieved with an elongate
stretchable textile member and conductive components associated
therewith, where the textile member provides dielectric separation
between the conductive components such that expansion and
contraction of the textile member results in a change in the
spacing between the conductive components, resulting in a change of
capacitance, by which respiration can be measured.
[0022] The subject invention, however, in other embodiments, need
not achieve all these objectives and the claims hereof should not
be limited to structures or methods capable of achieving these
objectives.
[0023] This invention features a physiological monitoring garment
including a first elastic fabric portion, a second elastic fabric
portion, and an elongate stretchable textile data/power bus between
the first fabric portion and the second fabric portion. The
elongate stretchable textile data/power bus includes a plurality of
integral conductors, woven, knitted, or braided along the length
thereof. One or more sensors are connected to the elongate
stretchable textile data/power bus. The first fabric portion may be
the upper portion of a shirt and the second fabric portion may be
the lower portion of the shirt. The first fabric portion may be
connected to the second fabric portion via the elongate stretchable
textile data/power bus. The elongate stretchable textile data/power
bus may be attached to the garment between the first fabric portion
and the second fabric portion. The physiological monitoring garment
may further include at least a third elastic fabric portion and at
least a second elongate stretchable textile data/power bus
including a plurality of integral conductors, woven, knitted, or
braided along the length thereof, and one or more sensors connected
to the at least second elongate stretchable textile data/power bus.
The plurality of conductors may be woven, knitted, or braided in a
strain relief pattern. The plurality of conductors may include
conductors for data transfer, conductors for power transfer, and
conductors structured and arranged to form an electronic shield for
reducing noise. Also, a coating of conductive material may be
disposed on the elongate stretchable textile data/power bus to form
an electrical shield for reducing noise. The strain relief pattern
may be out of the plane of the elongate stretchable textile
data/power bus or in the plane of the elongate stretchable textile
data/power bus. Connectors may connect the one or more sensors to
the elongate stretchable textile data/power bus, and the connectors
may be insulation displacement connectors.
[0024] A sensor connected to the elongate stretchable textile
data/power bus may include a respiration monitoring device, and the
respiration monitoring device may include at least a first elongate
stretchable textile member, a first conductive component associated
with said textile member, and a second conductive component
associated with said textile member. Threads of the textile member
provide dielectric separation between the at least first and second
conductive components so that the expansion and contraction of the
textile member results in a change in the spacing between the first
and second conductive components for measuring change in
capacitance. The first conductive component may include woven,
knitted, or braided conductive threads integral with the first
textile member. There may be a plurality of elongate stretchable
textile members adjacent each other, and each may include integral
woven, knitted, or braided conductive threads. The respiration
monitoring device may be disposed in or on the garment proximate
the data/power bus.
[0025] Another sensor connected to the elongate stretchable textile
data/power bus may include a flexible circuit board configured as
an electrode, a conductive portion on one surface of the flexible
circuit board, and a dielectric material on the conductive portion.
An opposing surface of the flexible circuit board may include
signal conditioning circuitry, or the flexible circuit board may be
connected to a second flexible circuit board that includes signal
conditioning circuitry. Conductive traces may interconnect the
conductive portion with the signal conditioning circuitry. The
conductive portion may be a conductive foil laminated on the
flexible circuit board. The conductive portion may be conductive
material sputtered or plated on the flexible circuit board. The
dielectric material may be material sputtered, laminated,
evaporated, or spun onto the conductive portion. The sensor may
include an insulating edge for preventing short circuits. The
sensor may be configured to include at least two electrodes, and
each of the electrodes may each include signal conditioning
circuitry.
[0026] This invention also features a physiological monitoring
garment including an elastic fabric portion, at least one elongate
stretchable textile data/power bus disposed on the elastic fabric
portion, the elongate stretchable textile data/power bus including
a plurality of integral conductors, woven, knitted, or braided
along the length thereof, and one or more sensors connected to the
elongate stretchable textile data/power bus. The plurality of
conductors may be woven, knitted, or braided in a strain relief
pattern. The plurality of conductors may include conductors for
data transfer, conductors for power transfer, and conductors
structured and arranged to form an electronic shield for reducing
noise. A coating of conductive material may be disposed on the
elongate stretchable textile data/power bus to form an electrical
shield for reducing noise. The strain relief pattern may be out of
the plane of the elongate stretchable textile data/power bus or in
the plane of the elongate stretchable textile data/power bus.
Connectors may connect the one or more sensors to the elongate
stretchable textile data/power bus, and the connectors may be
insulation displacement connectors.
[0027] A sensor connected to the elongate stretchable textile
data/power bus may include a respiration monitoring device, and the
respiration monitoring device may include at least a first elongate
stretchable textile member, a first conductive component associated
with said textile member, and a second conductive component
associated with said textile member. Threads of the textile member
provide dielectric separation between the at least first and second
conductive components so that the expansion and contraction of the
textile member results in a change in the spacing between the first
and second conductive components for measuring change in
capacitance. The first conductive component may include woven,
knitted, or braided conductive threads integral with the first
textile member. There may be a plurality of elongate stretchable
textile members adjacent each other, and each may include integral
woven, knitted, or braided conductive threads. The respiration
monitoring device may be disposed in or on the garment proximate
the data/power bus.
[0028] Another sensor connected to the elongate stretchable textile
data/power bus may include a flexible circuit board configured as
an electrode, a conductive portion on one surface of the flexible
circuit board, and a dielectric material on the conductive portion.
An opposing surface of the flexible circuit board may include
signal conditioning circuitry, or the flexible circuit board may be
connected to a second flexible circuit board that includes signal
conditioning circuitry. Conductive traces may interconnect the
conductive portion with the signal conditioning circuitry. The
conductive portion may be a conductive foil laminated on the
flexible circuit board. The conductive portion may be conductive
material sputtered or plated on the flexible circuit board. The
dielectric material may be material sputtered, laminated,
evaporated, or spun onto the conductive portion. The sensor may
include an insulating edge for preventing short circuits. The
sensor may be configured to include at least two electrodes, and
each of the electrodes may each include signal conditioning
circuitry.
[0029] This invention further features a physiological monitoring
garment including an elongate stretchable textile data/power bus
including a plurality of integral conductors, woven, knitted, or
braided along the length thereof, and one or more sensors connected
to the elongate stretchable textile data/power bus.
[0030] This invention also features a physiological monitoring
garment including a first fabric portion, a second fabric portion,
and an elongate stretchable textile data/power bus between the
first fabric portion and the second fabric portion. The elongate
stretchable textile data/power bus includes a plurality of integral
conductors, woven, knitted, or braided along the length thereof in
a strain relief pattern. A respiration monitoring device is
connected to the textile data/power bus and includes a first
elongate stretchable textile member, a first conductive component
associated with the textile member, and a second conductive
component associated with the textile member. Threads of the
textile member provide dielectric separation between the first and
second conductive components so that the expansion and contraction
of said textile member results in a change in the spacing between
the first and second conductive components. At least two sensors
may be connected to the textile data/power bus. The sensors each
may include a flexible circuit board configured as an electrode, a
conductive portion on one surface of the flexible circuit board,
and a dielectric material on the conductive portion.
[0031] This invention also features a physiological monitoring
garment including an elastic fabric portion, at least one elongate
stretchable textile data/power bus disposed on the elastic fabric
portion, the elongate stretchable textile data/power bus including
a plurality of integral conductors, woven, knitted, or braided
along the length thereof in a strain relief pattern, and a
respiration monitoring device connected to the textile/data power
bus. The respiration monitoring device includes a first elongate
stretchable textile member, a first conductive component associated
with the textile member, a second conductive component associated
with the textile member, and threads of the textile member
providing dielectric separation between the first and second
conductive components so that the expansion and contraction of the
textile members results in a change in the spacing between the
first and second conductive components. The physiological
monitoring garment also includes at least two sensors connected to
the textile data/power bus, the sensors each including a flexible
circuit board configured as an electrode, a conductive portion on
one surface of the flexible circuit board, and a dielectric
material on the conductive portion.
[0032] This invention further features a physiological monitoring
garment including a first fabric portion, a second fabric portion,
and an elongate stretchable textile data/power bus between the
first fabric portion and the second fabric portion, the elongate
stretchable textile data/power bus including a plurality of
integral conductors, woven, knitted, or braided along the length
thereof in a strain relief pattern. The physiological monitoring
garment may include at least a third elastic fabric portion and at
least a second elongate stretchable textile data/power bus
including a plurality of integral conductors, woven, knitted, or
braided along the length thereof, and one or more sensors connected
to the at least second elongate stretchable textile data/power
bus.
[0033] This invention also features a physiological monitoring
garment including an elastic fabric portion and at least one
elongate stretchable textile data/power bus disposed on the elastic
fabric portion, the elongate stretchable textile data/power bus
including a plurality of integral conductors, woven, knitted, or
braided along the length thereof in a strain relief pattern.
[0034] This invention also features a physiological monitoring
garment including a first fabric portion, a second fabric portion,
and an elongate stretchable textile data/power bus between the
first fabric portion and the second fabric portion. The elongate
stretchable textile data/power bus includes a plurality of integral
conductors, woven, knitted, or braided along the length thereof in
a strain relief pattern. A respiration monitoring device is
connected to the data/power bus and includes a first elongate
stretchable textile member, a first conductive component associated
with the textile member, a second conductive component associated
with the textile member, and threads of the textile member
providing dielectric separation between the first and second
conductive components so that the expansion and contraction of the
textile member results in a change in the spacing between the first
and second conductive components. The physiological monitoring
garment may include at least a third elastic fabric portion and at
least a second elongate stretchable textile data/power bus
including a plurality of integral conductors, woven, knitted, or
braided along the length thereof, and one or more sensors connected
to the at least second elongate stretchable textile data/power
bus.
[0035] This invention further features a physiological monitoring
garment including an elastic fabric portion, at least one elongate
stretchable textile data/power bus disposed on the elastic fabric
portion, the elongate stretchable textile data/power bus including
a plurality of integral conductors, woven, knitted, or braided
along the length thereof in a strain relief pattern, and a
respiration monitoring device connected to the data/power bus. The
respiration monitoring device includes a first elongate stretchable
textile member, a first conductive component associated with the
textile member, a second conductive component associated with the
textile member, and threads of textile member providing dielectric
separation between the first and second conductive components so
that the expansion and contraction of the textile member results in
a change in the spacing between the first and second conductive
components.
[0036] This invention further features a physiological monitoring
garment including a first fabric portion, a second fabric portion,
an elongate stretchable textile data/power bus between the first
fabric portion and the second fabric portion, the elongate
stretchable textile data/power bus including a plurality of
integral conductors, woven, knitted, or braided along the length
thereof in a strain relief pattern, and at least one sensor
connected to the textile data/power bus, the sensor including a
flexible circuit board configured as an electrode, a conductive
portion on one surface of the flexible circuit board, and a
dielectric material on the conductive portion. The physiological
monitoring garment may include at least a third elastic fabric
portion and at least a second elongate stretchable textile
data/power bus including a plurality of integral conductors, woven,
knitted, or braided along the length thereof, and one or more
sensors connected to the at least second elongate stretchable
textile data/power bus.
[0037] This invention also features a physiological monitoring
garment including an elastic fabric portion, at least one elongate
stretchable textile data/power bus disposed on the elastic fabric
portion, the elongate stretchable textile data/power bus including
a plurality of integral conductors, woven, knitted, or braided
along the length thereof in a strain relief pattern. At least one
sensor is connected to the textile data/power bus, the sensor
including a flexible circuit board configured as an electrode, a
conductive portion on one surface of the flexible circuit board,
and a dielectric material on the conductive portion.
[0038] This invention also features a data/power bus for a garment,
the data/power bus including an elongate stretchable textile member
and a plurality of conductors woven, knitted, or braided along the
length thereof integral with threads of the elongate stretchable
textile member in a strain relief pattern. The strain relief
pattern may be out of the plane of the elongate stretchable
data/power bus or the strain relief pattern may be in the plane of
the elongate stretchable data/power bus. The data/power bus may
include connectors for attaching sensors to the data/power bus. The
plurality of conductors may include conductors for data transfer,
conductors for power transfer, and conductors structured and
arranged to form an electronic shield for reducing noise.
[0039] This invention further features a respiration monitoring
device including a first elongate stretchable textile member, a
first conductive component associated with the textile member, a
second conductive component associated with the textile member, and
threads of the textile member providing dielectric separation
between the first and second conductive components so that the
expansion and contraction of the textile member results in a change
in the spacing between the first and second conductive components.
The first conductive component may include woven, knitted, or
braided conductive threads integral with the textile member. There
may be first and second elongate stretchable textile members
adjacent each other and each may include integral woven, knitted,
or braided conductive threads.
[0040] This invention also features a sensor for a garment
including a flexible circuit board configured as an electrode, a
conductive portion on one surface of the flexible circuit board,
and a dielectric material on the conductive portion. The opposing
surface of the flexible circuit board may include signal
conditioning circuitry. The flexible circuit board may be connected
to a second flexible circuit board including signal conditioning
circuitry. Conductive traces may interconnect the conductive
portion with the signal conditioning circuitry. The conductive
portion may be a conductive foil laminated on the flexible circuit
board or the conductive portion may be conductive material
sputtered or plated on the flexible circuit board. The dielectric
material may be material sputtered, laminated, evaporated, or spun
onto the conductive portion.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0041] Other objects, features and advantages will occur to those
skilled in the art from the following description of a preferred
embodiment and the accompanying drawings, in which:
[0042] FIG. 1A is a schematic view of one example of a
physiological monitoring garment in accordance with the present
invention;
[0043] FIG. 1B is a schematic view of another example of a
physiological monitoring garment in accordance with the present
invention;
[0044] FIG. 1C is an enlarged schematic cross-sectional view of the
physiological monitoring garment of FIG. 1B;
[0045] FIG. 1D is another form of the physiological monitoring
garment in accordance with the present invention with a single
fabric section;
[0046] FIG. 1E is an enlarged schematic cross-sectional view of the
physiological monitoring garment of FIG. 1D;
[0047] FIG. 2 is a schematic view of one form of the elongate
stretchable textile data/power bus of the physiological monitoring
garment of FIG. 1A;
[0048] FIG. 3A is an enlarged schematic partial view of the
elongate stretchable textile data/power bus of FIG. 2 showing
breakouts in the fabric where individual conductive components may
be accessed for connection;
[0049] FIG. 3B is an enlarged cross-sectional view of a portion of
the elongate stretchable textile data/power bus of FIG. 3A;
[0050] FIG. 3C is an enlarged cross-sectional side view of a
portion of the elongate stretchable textile data/power bus of FIG.
3A;
[0051] FIG. 4 is an enlarged schematic partial view of another form
of the elongate stretchable textile data/power bus of the
physiological monitoring garment of FIG. 1A;
[0052] FIG. 5 is a schematic view of the elongate stretchable
textile data/power bus of FIG. 4;
[0053] FIG. 6 is a schematic view of the physiological monitoring
garment of FIG. 1A including sensors connected thereto;
[0054] FIGS. 7A-7B are enlarged cross-sectional views of one
example of an improved respiration monitoring device in accordance
with the present invention;
[0055] FIG. 7C is an enlarged cross-sectional view of another
example of an improved respiration monitoring device in accordance
with the present invention;
[0056] FIG. 8 is a schematic view showing the placement of the
improved respiration monitoring device of the subject invention
when in use on a subject or patient;
[0057] FIG. 9 is an enlarged schematic partial view of another
embodiment of the improved respiration monitoring device in
accordance with the present invention;
[0058] FIGS. 10A and 10B are enlarged schematic partial views of
another embodiment of the improved respiration monitoring device in
accordance with the present invention;
[0059] FIG. 11 is a schematic view of the improved respiration
monitoring device of FIGS. 10A and 10B;
[0060] FIG. 12 is a schematic view of the major components of one
prior art ECG sensor;
[0061] FIG. 13 is a schematic front view of the prior art ECG
sensor of FIG. 12;
[0062] FIG. 14 is a schematic rear view of an improved sensor in
accordance with the present invention;
[0063] FIG. 15 is a schematic front view of the improved sensor of
FIG. 14;
[0064] FIGS. 16A-16D are enlarged cross-sectional views of
alternative embodiments of the improved sensor of FIG. 14;
[0065] FIG. 17 is a schematic isometric view of the sensor of FIG.
14; and
[0066] FIG. 18 is a schematic view of the physiological monitoring
garment of FIG. 1A including the improved sensor of FIG. 14.
DETAILED DESCRIPTION OF THE INVENTION
[0067] Aside from the preferred embodiment or embodiments disclosed
below, this invention is capable of other embodiments and of being
practiced or being carried out in various ways. Thus, it is to be
understood that the invention is not limited in its application to
the details of construction and the arrangements of components set
forth in the following description or illustrated in the drawings.
If only one embodiment is described herein, the claims hereof are
not to be limited to that embodiment. Moreover, the claims hereof
are not to be read restrictively unless there is clear and
convincing evidence manifesting a certain exclusion, restriction,
or disclaimer.
[0068] One embodiment of a physiological monitoring garment in
accordance with the present invention is shown at 10 in FIG. 1A. As
shown, physiological monitoring garment 10 includes elastic fabric
portions 12 and 14. Elongate stretchable textile data/power bus 16
is disposed between elastic fabric portions 12 and 14. Elongate
stretchable textile data/power bus 16 includes a plurality of
integral conductors 20 woven, knitted, or braided along the length
of elongate stretchable textile data/power bus 16 and one or more
sensors 30, 32 connected to the elongate stretchable textile
data/power bus. These latter features are discussed more fully
below, as well as the multiple sensors which are not limited to any
particular type or number and which may be attached to elongate
stretchable textile data/power bus 16. In the example shown, the
elastic fabric portion 12 is connected to the elastic fabric
portion 14 via elongate stretchable textile data/power bus 16.
Elongate stretchable textile data/power bus 16 is attached to
garment 10 between elastic fabric portion 12 and elastic fabric
portion 14. As shown, elastic fabric portion 12 is the upper
portion of a shirt, and fabric portion 14 is the lower portion of a
shirt, although this is not a necessary limitation of the
invention. Elongate stretchable textile data/power bus 16 may also
be located at any point between elastic fabric portions 12 and 14.
Further, elongate stretchable textile data/power bus 16 or another
similar bus may be located between the right and left elastic
fabric portions of the garment such that it extends vertically
through physiological monitoring garment 10 rather than around the
torso of the wearer.
[0069] Also, physiological monitoring garment 10, FIG. 1B, may
include two or more elongate stretchable textile data/power buses
16 and 16' as desired for a particular application. In such an
example, elongate stretchable textile data/power bus 16 is between
fabric portions 12 and 14 and elongate stretchable textile
data/power bus 16' is between fabric portions 14 and 15. Elongate
stretchable textile data/power bus 16, FIG. 1C, may connect fabric
portions 12 and 14, and elongate stretchable textile data/power bus
16' may connect fabric portions 14 and 15. Elongate stretchable
textile data/power bus 16' may also include a plurality of
conductors 20' (not shown), woven, knitted, or braided along the
length of elongate stretchable textile data/power bus 16'. Elongate
stretchable textile data/power bus 16' may also include one or more
sensors 30', 32' attached to it. Also, elongate stretchable textile
data/power bus 16, FIG. 1D, may be disposed on fabric portion 12 of
physiological monitoring garment 10, for example, as shown in FIG.
1E in cross-section but not to scale. In the latter case, there is
a single fabric portion 12 instead of multiple fabric portions.
Fabric portion 12 may be in the form of a sports bra or tube top,
for example. Elongate stretchable textile data/power bus 16 may be
attached to fabric portion 12 by any known appropriate means.
Overall, there may be any number of fabric portions as desired, and
there may be any number of desired elongate stretchable textile
data power buses, also as desired or needed for a particular
application.
[0070] In another example, physiological monitoring garment 10
including elongate stretchable textile data/power bus 16 as shown
in FIG. 1D, may be worn as a strap directly on the subject or
patient underneath the fabric portion (not shown), without being
attached to a fabric portion, such as fabric portion 12, at
all.
[0071] In all embodiments, the elastic fabric portions, including
elastic fabric portions 12, 14 and 15, FIGS. 1A-1E, preferably
include an elastic material such as Lycra, which has radial and
longitudinal stretchability. The elastic material, i.e. Lycra, is
incorporated with textile fibers such as nylon, polyester, silk, or
cotton, by weaving, knitting or braiding. This allows physiological
monitoring garment 10 to be form fitting yet comfortable, such that
various sensors as described below are properly held in position.
Furthermore, the moisture sensitivity of physiological monitoring
garment 10 may be reduced using water-repellant coatings, and
biocidal materials may be incorporated into physiological
monitoring garment 10 to minimize bacterial growth. In any of the
foregoing examples, the elongate stretchable textile data/power bus
of the physiological monitoring garment may include integral
conductors, connectors, materials and/or sensors as will now be
more fully described.
[0072] As noted above, elongate stretchable textile data/power bus
16, FIG. 2, typically includes a plurality of integral conductors
20 which are woven, knitted, or braided along the length of
stretchable textile data/power bus 16. In FIG. 2 integral
conductors 20 are shown as woven with external loops from elongate
stretchable textile data/power bus 16. This can also be effective
for making electrical connections, as discussed further below. In
use, integral conductors 20 may not be visible to the user.
Stretchable textile data/power bus 16 also includes textile portion
18. Textile portion 18 of physiological monitoring garment 10 may
be comprised of either natural or synthetic textile materials such
as polyester, cotton or nylon. In a preferred embodiment, textile
portion 18 is comprised of Lycra combined with natural or synthetic
textile materials through weaving, knitting, or braiding, in order
to provide elasticity.
[0073] Typically, plurality of integral conductors 20 in
stretchable textile data/power bus 16 are woven, knitted, or
braided in a strain relief pattern as described below. When the
subject invention is in use, textile portion 18 expands or
stretches, and the strain relief pattern of integral conductors 20
allows them to lengthen and shorten. FIG. 3A is an enlarged view of
elongate stretchable textile data/power bus 16 with plurality of
integral conductors 20 woven in strain relief pattern 22 in the
plane of elongate stretchable textile data/power bus 16. Integral
conductors 20, FIG. 3B, include conductors 20' for data transfer
and power transfer. Integral conductors 20 may also include
conductors 20'' structured and arranged to form an electrical
shield for reducing noise, as known in the art. Alternatively, a
coating of conductive material 19, FIG. 3C, such as metal, may be
disposed on elongate stretchable textile data/power bus 16 to form
an electrical shield to reduce noise.
[0074] In another embodiment, the strain relief pattern 25, FIG. 4,
for conductors 20, shown as 20a . . . 20n, is perpendicular to or
out of the plane of elongate stretchable textile data/power bus 16.
In this embodiment, integral conductors 20a . . . 20n may be
partially visible to the user. Alternatively, the strain relief
pattern may be a combination of in plane and out of plane (not
shown). Either in plane strain relief pattern 22 or out of plane
strain relief pattern 25 of integral conductors 20 and 20a . . .
20n may resemble a sinusoidal pattern.
[0075] In one example, strain relief patterns 22 and 25, FIGS. 3A
and 4, are achieved by weaving, knitting or braiding integral
conductors 20 and 20a . . . 20n when textile portion 18 is fully or
partially stretched. Integral conductors 20, 20a . . . 20n may
include conventional insulated cables or wires. Thus, when textile
portion 18 is released from its stretched configuration, integral
conductors 20 form a strain relief pattern whereby slack is
introduced into integral conductors 20. In this way, when textile
portion 18 of stretchable textile data/power bus 16 is expanded or
stretched during use, damage to integral conductors 20 due to
stretching forces is lessened or eliminated.
[0076] Sensors 30-38, FIG. 6 may be mechanically attached to
physiological monitoring garment 10 through energy welding
processes including ultrasonic welding, thermal melding, RF
welding, or other suitable techniques. Preferably, however, sensors
30-38 are configured to take greater advantage of physiological
monitoring garment 10 by being attachable to and detachable from
stretchable textile data/power bus 16 via sensor connectors 100.
Elongate stretchable textile data/power bus 16 may include one or
more connectors 100 for connecting sensors 30-38, which are
included in physiological monitoring garment 10, to elongate
stretchable textile data/power bus 16. Insulation displacement
(IDC) type connectors, which are generally available off the shelf,
or end type connectors, may be used as connectors 100 to attach
sensors 30-38 to integral conductors 20. Such IDC connectors are
best shown in FIG. 5 at 100. Alternatively, integral conductors 20,
FIG. 3A, may be spliced or broken to allow for connections to
sensors 30-38, FIG. 6. It will be apparent that, as necessary or
desired, sensors 30-38 may be attached to one another, and then
connected to elongate stretchable textile data/power bus 16.
[0077] The outputs of sensors 30-38, FIG. 6, are typically fed into
conditioning electronics 105 in processing hub 112, which includes
microprocessor 115, and may include an analog-to-digital converter
114 and filters 116. Microprocessor 115 will also typically include
appropriate software/algorithms for determining the applicable
health status of the patient from the data and information
received. Processing hub 112 and power supply 120 are electrically
connected to elongate stretchable textile data/power bus 16.
Preferably, processing hub 112 and power supply 120 are
incorporated into physiological monitoring garment 10, but this is
not a necessary limitation of the invention. For example,
processing hub 112 and power supply 120 may attach to or snap onto
the patient's belt or be hip mounted, or otherwise be carried by
the patient, depending on the needs of a particular desired
application. Additionally, power source 120 is preferably not
separate from processing hub 112 but is in one package (not shown)
as part of a hip mounted package, for example.
[0078] Additionally, a wireless telemetry system 200 may be
connected to elongate stretchable textile data/power bus 16 of
physiological monitoring garment 10 for wireless communication via
radio frequency or other conventional means. Wireless telemetry
system 200 may also be incorporated into physiological monitoring
garment 10 or part of a hip mounted package with processing hub 112
and/or power supply 120, for remote connection between the patient
user and personal computer 300 at a distance.
[0079] Thus, physiological monitoring garment 10 including elongate
stretchable textile data/power bus 16 provides the capability of
data and power routing from a multiplicity of sensors 30-38, to and
from processing hub 112 and power supply 120, and does so while
effectively and comfortably maintaining pressure on sensors 30-38
to hold sensors 30-38 in place against the patient or subject.
Physiological monitoring garment 10 further allows sensors 30-38 to
be detachable via connectors 100 in stretchable textile data/power
bus 16. This gives physiological monitoring garment 10 adaptability
and washability without risk of damage to potentially fragile
and/or expensive sensors.
[0080] The physiological monitoring garment of the present
invention is not limited to any particular type of sensor, however.
Any number or type of sensors may be utilized, depending on a
particular desired application or health status information
desired. Sensors which may be connected to elongate stretchable
textile/data power bus 16 in physiological monitoring garment 10
include electrocardiogram (ECG) sensors 32, sensors for muscle
activity (EMG) 33, skin temperature 34, body orientation 36, and
motion sensors 38, and may include associated alarm systems to
alert the patient to various physiological conditions.
[0081] Another type of sensor for use with physiological monitoring
garment 10 is respiration sensor 30. Preferably, respiration sensor
30 is an improved respiration sensor for use with physiological
monitoring garment 10, namely respiration monitoring device 40,
FIGS. 7A-7C. Conventional respiration sensors include impedance
pneumography, inductive plethysmography, or measurements of changes
in strain (resistive strain gage or piezoelectric), tension or
pressure which can be used to infer respiration.
[0082] In contrast, respiration monitoring device 40 in accordance
with this invention provides textile based capacitive transduction
as a means for sensing respiration. Conductive portions act as
electrodes and non-conductive textile material acts as a dielectric
material between the conductive portions. Particularly, respiration
monitoring device 40 includes elongate stretchable textile member
42, and conductive components or members 44 and 46 associated with
textile member 42. Textile member 42, including threads 48 of
textile member 42, provide dielectric separation between conductive
components 44 and conductive component 46 such that expansion and
contraction of textile member 42 results in a change in the spacing
between conductive components 44 and 46. Conductive components 44
and 46 act as electrodes, and are used to sense the capacitance of
textile member 42, which acts as a non-conductive dielectric.
Textile member 42 may be comprised of either synthetic or natural
textile materials such as polyester, cotton, or nylon.
[0083] Respiration monitoring device 40 in use on a patient or
subject is preferably placed around the patient near the diaphragm
of patient 55, FIG. 8. As the patient inhales and exhales, textile
member 42, FIGS. 7A and 7B, expands and contracts, thus causing the
length of textile member 42 to change. This change in length in
turn changes the spacing between conductive components 44 and 46,
which changes the capacitance. In general, the theoretical
capacitance of a dielectric between two conductive plates is:
C=A.di-elect cons..sub.o/[d+t(1/.di-elect cons..sub.r-1)] (1)
where A is the area of the conductive plates, .di-elect cons..sub.o
is the dielectric of any air between the plates, d is the spacing
between the plates, t is the thickness of the dielectric, and
.di-elect cons..sub.r is the dielectric of the material. Therefore,
it can be seen that the capacitance of a dielectric material is
proportional to the dielectric constant of the material and the
thickness of the material or spacing between the electrodes. For
respiration monitoring device 40, as textile member 42 is
stretched, the spacing between conductive components or members 44
and 46 decreases, decreasing the space between conductive
components "electrodes" 44 and 46. Tests have revealed that
measured capacitance varies nearly linearly with elongation of
respiration monitoring device 40. From this capacitive transduction
mechanism, including sensing the change in capacitance, both the
type and rate of respiration can be determined.
[0084] In further detail, respiration monitoring device 40, FIGS.
7A and 7B, includes textile member 42 having threads 48, as well as
conductive components 44 and 46 shown a distance d.sub.1 apart.
When the subject or patient inhales, for example, textile member 42
stretches lengthwise, as shown at 50, FIG. 7B, along the length of
respiration monitoring device 40. As textile member 42 stretches,
the distance between conductive components 44 and 46 decreases to a
distance d.sub.2, where d.sub.2 is less than d.sub.1. As noted, the
change in the spacing between conductive components 44 and 46
changes the capacitance, which is an indication of respiration.
Conductive components 44 and 46 may be woven, knitted or braided
integral with textile member 42.
[0085] Also, in another example, there may be a plurality of
conductive components 44a . . . 44n and 46a . . . 46n, FIG. 7C,
which may also be woven, knitted or braided integral with textile
member 42. The operation of these conductive components will be the
same as described above in FIGS. 7A and 7B, that is, as textile
member 42 stretches lengthwise, distance d.sub.1' between
conductive threads 44a and 46a will decrease. The same will hold
true with conductive threads 44b . . . 44n and 46b . . . 44n. As
shown in FIGS. 7A-7C, the stretching is in plane.
[0086] In another embodiment of respiration monitoring device 40,
FIG. 9, stretching of the textile occurs out of plane, but
capacitance is measured in much the same way, namely, the distance
between conductive components or threads changes which is reflected
as a change in capacitance. In this embodiment, respiration
monitoring device 40 includes elongate stretchable textile members
60 and 62 adjacent each other. Each of elongate stretchable textile
members 60 and 62 also include threads 48. Textile member 60
further includes integral woven, knitted or braided conductive
component 44 including conductive threads or yarns 64a . . . 64n,
and textile member 62 includes conductive component 46 including
integral woven, knitted or braided conductive threads 66a . . .
66n, such that textile member 60 is between conductive threads or
yarns 64a . . . 64n and 66a . . . 66n.
[0087] In this configuration, a textile/conductive laminate
structure is formed. With conductive threads 64a . . . 64n and 66a
. . . 66n acting as electrodes and textile member 60 as a
dielectric, when respiration monitoring device 40 stretches
lengthwise as shown at 50, textile member 60 becomes thinner.
Therefore, the spacing between conductive threads 64a . . . 64n and
66a . . . 66n is less, thus changing the capacitance. Elongate
stretchable textile members 60 and 62 are preferably connected
along stitched regions 65 at predetermined spaced intervals. In
this example, the conductive threads which collectively serve as
the electrodes also undergo a change in respective electrode area
as they are stretched. This effects a change in capacitance in
addition to the change in capacitance due to the change caused by
the spacing between the conductive threads.
[0088] FIGS. 10A and 10B show respiration monitoring device 40 with
a single elongate stretchable textile layer or member 60'. In a top
view, FIG. 10A, integral woven, knitted or braided conductive
component 44 includes conductive threads 64a' . . . 64n' on top
side 65 of elongate stretchable textile member 60', and conductive
threads 64a'' . . . 64n'', FIG. 10B, on bottom side 67 of elongate
stretchable textile member 60'. In this single layer or member
configuration, respiration monitoring device 40 can be even
thinner.
[0089] In any of the foregoing embodiments, respiration monitoring
device 40 may be disposed in or on physiological monitoring garment
10, FIG. 6 as an improved respiration sensor 30. Respiration
monitoring device 40 may be in or on the garment as shown, or
respiration monitoring device 40 may be disposed on elongate
stretchable textile data/power bus, and attached by any
conventional means. In either case, respiration monitoring device
40 is connected to elongate stretchable textile data/power bus 16.
Alternatively, respiration monitoring device 40 may be in the form
of a strap. The respiration monitoring device 40 of FIGS. 10A and
10B is shown fully, in strap form, in FIG. 11. In this view, only
one conductive component 46 including conductive threads 66a . . .
66n and only one textile member 62 are discernible. Fastener 200
such as Velcro at each end of respiration monitoring device 40
holds respiration monitoring device 40 tightly around the subject
or patient. To minimize the effects of moisture, respiration
monitoring device 40 is typically treated with a moisture-resistant
material, or a coating is applied such as fluoropolymer fabric
water proofing spray. Other treatments include, for example,
incorporation of biocidal materials in order to minimize bacterial
growth. Thus, respiration monitoring device 40 provides textile
based capacitive sensing in a convenient, comfortable and
functional form as a means for sensing respiration rate and type of
respiration.
[0090] As noted above, other known sensors such as sensor 32, FIG.
6, may also be used with physiological monitoring garment 10.
However, a majority of such sensors, i.e. bioelectrode sensors used
for bioelectric sensing (e.g., ECG etc.) are conductively coupled,
and suffer from a number of disadvantages, such as: extraneous
noise induced by contact movement or pressure; base line drift
associated with shifts in D.C. levels at the electrode-skin
interface, and partial rectification or polarization of the
monitored signal. Conductive electrodes are also size-sensitive.
Electrode application becomes easier with decreasing size, but
since source impedance increases with decreasing size, small
electrodes are subject to greater noise. Furthermore, these
conventional electrodes are subject to chemical reactions or even
drying which can affect signals and tend to cause skin irritation,
especially after extended use.
[0091] In contrast, capacitively coupled electrodes eliminate any
current flow between the skin and the electrode. This decoupling
has advantages including: eliminating the possibility for tissue
polarization; minimizing sensitivity to chemical reactions;
eliminating contact and movement artifacts; minimizing noise
sensitivity; and providing an increased level of safety, since
electrical problems in the conditioning electronics cannot create a
shock to the user. Thus, the advantages of capacitively coupled
electrodes over any conductive electrode are clear.
[0092] In one example, sensor 32, FIG. 6, for use with
physiological monitoring garment 10 of the subject invention, a
conventional bioelectrode sensor 70, FIG. 12, which may be a
capacitive electrode such as an electrocardiogram (ECG) sensor.
Although an improvement over conductive electrodes, such a
conventional prior art sensor 70 typically includes thick rigid
plastic housing 72, printed circuit board with conditioning
electronics 74, and a stamped metal electrode 76, FIG. 13 which
usually includes a thin oxide coating 77 on its front side 78. Even
though this form of capacitive electrode does not require complete
surface contact with the skin, however, because it is rigid and
thick, prior art sensor 70 is prone to bridging, i.e. sensor 70
does not remain in full contact with the patient's skin. Folds of
flesh, either fat or muscle, can lift rigid disk sensor 70 on an
edge, leading to a complete loss of contact. When bridging occurs,
a true signal from sensor 70 is not maintained, resulting in less
than accurate readings.
[0093] Although such conventional sensors may be used, even with
their inherent disadvantages, preferably sensor 32, FIG. 6, for use
with physiological monitoring garment 10 of the subject invention
is improved sensor 80, FIG. 14. Sensor 80 includes flexible circuit
board 82 configured as an electrode, with conductive portion or
layer 84, FIG. 15, on one surface 86. Flexible circuit board 82 is
preferably comprised of a flexible material such as a liquid
crystal polymer or polyesters. Conductive layer or portion 84 can
be etched using conventional circuit board fabrication techniques
to form specific circuit patterns on the surface. In this way,
opposing surface 88, FIG. 14, of flexible circuit board 82
typically includes signal conditioning circuitry 90, although this
is not a necessary limitation of the invention as discussed below.
Conductive traces 94 interconnect conductive portion 84 with signal
conditioning circuitry 90. The flexible nature of circuit board 82
allows the low-profile signal conditioning circuitry 90 to be
located with flexible circuit board 82, thus minimizing electrical
connections. In one example, conductive portion 84 is a conductive
foil laminated on flexible circuit board 82. Conductive portion 84
may also be conductive material that is sputtered or plated on
flexible circuit board 82. Thermal lamination or deposition
techniques such as vapor deposition may also be utilized to
integrate conductive portion 84 onto flexible circuit board 82.
Conductive layer or portion 84 may include a thin layer of copper,
although the invention is not limited to this material.
[0094] Dielectric material or coating 96, FIG. 15, is disposed on
conductive portion 84. In FIG. 15, dielectric material 96 is
invisible and covers the entirety of conductive portion 84 and
flexible circuit board 82 on this front side. Dielectric material
96 separates flexible circuit board 82, acting as an electrode,
from the patient's tissue. As known in the art, changes in
biological signals induce a charge in the electrode
electrostatically. When dielectric material 96 completely covers
conductive portion 84 on the front side of improved sensor 80, it
forms insulating edge 97 to prevent short circuiting. Dielectric
material 96 may include ceramics or polymers. Dielectric material
96 may include oxides and nitrides such as titanium oxide, silicon
oxide or silicon dioxide, titanium oxide or titanium dioxide.
Dielectric material 96 may be sputtered, laminated, evaporated, or
spun onto conductive portion 84, with a typical thickness of
approximately 100 nanometers to 1 micron.
[0095] As noted, flexible circuit board 82, FIG. 16A, preferably
includes signal conditioning circuitry 90, and conductive traces 94
interconnect conductive portion 84 with signal conditioning
circuitry 90. However, signal conditioning circuitry 90', FIG. 16B,
may be included on second flexible circuit board 83 connected by
wire 99 or other suitable means to flexible circuit board 82, or
adjacent conductive portion 84 on flexible circuit board 82, FIG.
16C. In another example, flexible circuit board 82, FIG. 16D, may
be configured as at least two electrodes 400, 402 with conductive
portions 84' and 84'', and dielectric material 96', 96'',
respectively, and each electrode 400, 402 may include signal
conditioning circuitry 90'' and 90'''.
[0096] The result is improved sensor 80 which is flexible, thin and
low profile, as best shown in FIG. 17. These features make improved
sensor 80 more comfortable, and decrease the likelihood of bridging
and its effects. Also, with flexible circuit board 82 configured as
an electrode and dielectric material disposed on the surface for
contact with the patient's skin, sensor 80 acts as a dry capacitive
sensor. Thus, the necessity of conductive lubricants or gels, which
are required for conventional conductive sensors is eliminated.
[0097] For ECG monitoring, for example, in operation physiological
monitoring garment 10, FIG. 18, will typically include two sensors
80 and 80', and may include as many as twelve sensors placed at
various locations on the subject or patient as known in the art. In
accordance with the present invention, typically one conductive
electrode 110 is used as a driven ground to reduce the effects of
noise. It is well known that ECG signal strength increases with
decreasing distance and orientation to the heart muscle. Thus, when
sensor 80 is utilized as an ECG sensor, sensors 80 and 80', are
suitably placed on the patient at optimum locations for ECG
recording, with locations being known by those skilled in the art.
For capacitively coupled electrodes such as improved sensor 80,
high impedance buffer electronics 118 will typically be included
between sensor 80 and conditioning electronics 105. This is due to
the time constant, .tau., that exists in the equivalent RC circuit.
Heart signal detection requires low frequency response with a large
time constant since the events themselves are relatively slow.
Furthermore, buffer electronics 118 may act as a transformer to
make the signal compatible with conventional monitoring systems,
such as conventional ECG monitoring which are typically designed
for low source impedance sensors. The signals from buffer
electronics 118 can then be fed to the analog-to-digital converter
114 and filters 116 in processing hub 112, which includes
microprocessor 115. In accordance with improved sensor 80, buffer
electronics 118 are typically included on flexible circuit board
82, FIG. 14. As noted above, however, buffer electronics 118 need
not be on flexible circuit board 118 but may be on a second circuit
board, for example. Although the operation of sensor 80 has been
described as associated with ECG monitoring, sensor 80 may be used
for EMG (electromyography) monitoring or EEG
(electroencephalograph) monitoring as well.
[0098] The physiological monitoring garment of the present
invention thus provides a comfortable non-obtrusive, versatile,
robust system for monitoring any number of physiological conditions
under dynamic conditions and environments, and it does so while the
subject or patient remains ambulatory. The garment is useful for
ambulatory monitoring, whether in-patient, out-patient, or for
non-clinical use, such as athletic performance training, sleep
studies, or detection of the onset of sudden infant death syndrome.
The inclusion of the stretchable textile data/power bus provides
power and data transfer and routing to and from a variety of
sensors, which can be attached to or detached from the stretchable
textile data/power bus. Thus, the physiological monitoring garment
can be washed, without damage to the sensors, and because
stretchable textile data/power bus is incorporated into the
physiological monitoring garment, it is more comfortable than
wiring attached to or surrounding the patient. Also, the improved
respiration monitoring device and flexible sensor according to the
present invention can be attached or connected to the garment. The
respiration monitoring device provides the advantage of added
comfort as well as textile based capacitive transduction as a means
for sensing respiration. The flexible sensor provides a low profile
structure with flexibility to decrease bridging effects and
distinct, clear signals for indicating physiological status. By
utilizing capacitance, in contrast to conductive systems, there is
no direct electrical contact from the patient's skin to the
electrode. There is an increased level of safely for the patient or
subject, and conductive gels or pastes are not necessary.
[0099] Although specific features of the invention are shown in
some drawings and not in others, this is for convenience only as
each feature may be combined with any or all of the other features
in accordance with the invention. The words "including",
"comprising", "having", and "with" as used herein are to be
interpreted broadly and comprehensively and are not limited to any
physical interconnection. Moreover, any embodiments disclosed in
the subject application are not to be taken as the only possible
embodiments. Other embodiments will occur to those skilled in the
art and are within the following claims.
[0100] In addition, any amendment presented during the prosecution
of the patent application for this patent is not a disclaimer of
any claim element presented in the application as filed: those
skilled in the art cannot reasonably be expected to draft a claim
that would literally encompass all possible equivalents, many
equivalents will be unforeseeable at the time of the amendment and
are beyond a fair interpretation of what is to be surrendered (if
anything), the rationale underlying the amendment may bear no more
than a tangential relation to many equivalents, and/or there are
many other reasons the applicant can not be expected to describe
certain insubstantial substitutes for any claim element
amended.
* * * * *
References