The present invention generally relates to signal measurement, and, more
particularly, to a device for measuring electrocardiogram (ECG) signals, abdominal EMG signals, Maternal ECG signals etc..
BACKGROUND OF THE INVENTION
[0002] Advancement in the field of medical diagnosis and examination has brought
about various innovations, and technologies over the years. Monitoring of Electrocardiogram
(ECG) signals has been widely used on adult patients for detecting medical conditions, for
example, abnormities associated with the condition of heart. Monitoring of fetal ECG can be
difficult due to the co-existence of maternal and fetal signals in raw signals acquired from a
patient, as well as the relatively low fetal signal level relative to the maternal signal and other
noise sources. Some conventional approaches to collecting fetal ECG signals include placing
a wire electrode onto the fetal scalp. Although the fetal scalp electrode may provide a
relatively clean fetal signal, this procedure can only be performed under limited clinical
circumstances (e.g., when a patient is in labor, has ruptured amniotic membranes, and has a
dilated cervix) and thus may not be suitable for the vast majority of pregnant and laboring
patients. The placement of the fetal scalp electrode may also present certain risks to fetal
safety, as rare cases of fetal scalp abscess and newborn death have been reported.
[0003] Further, other observation methods like Doppler ultrasound measurements
also need the continuous attention of a trained physician, making them unsuitable for long-term observation.
[0004] Therefore, non-invasive FECG tends to be a preferred method to provide
comfort to pregnant women in comparison to invasive FECG. FECG through abdominal
FECG electrodes, i.e., through Non-invasive (NIFECG) monitoring, has a widespread clinical
acceptance as it is suitable for long-term recordings without surgery, unlike invasive.
[0005] In prolonged measurement periods in ambulatory monitoring through
abdominal electrodes, comfort in placing and wearing the sensors is crucial, imposing additional requirements on the electrode spacing and number of sensors used. When we talk about electrode spacing and the number of sensors used, electrode orientation and distance significantly influence the measurement quality of the signals of interest.

SUMMARY OF THE INVENTION
[0006] In view of the foregoing disadvantages inherent in the prior art, the general
purpose of the present invention is to provide an abdominal signal measuring device to include all advantages of the prior art, and to overcome the drawbacks inherent in the prior art.
[0007] An object of the present invention is to continually provide accurate FECG
measurements.
[0008] Another object of the present invention is to measure electrocardiogram (ECG) signals, abdominal EMG signals, Maternal ECG signals etc..
[0009] Another object of the present invention is to provide an abdominal signal
measuring device that can be utilized with considerable ease.
[0010] Another object of the present invention is to provide an abdominal signal
measuring device that precludes a possibility of having electrode distance greater than preferred.
[0011] To achieve the above objects, in an aspect of the present invention, an
abdominal signal measuring device is provided. The device of the present invention includes a holding member, a set of arm members. Each of the set of arm members comprise a curvilinear body portion having a first end portion adapted to movably hold at least one sensing electrode, and a second end portion opposite to the first end connected to the holding member. The set of arm members are positioned at a predetermined distance with respect to one another and with respect to the holding member. Accordingly each sensing electrode continues to remain separated from corresponding sensing electrodes by at least a predetermined liner distance, and each sensing electrode continues to remain positioned, with respect to corresponding sensing electrodes, at a predetermined angular position.
[0012] This together with the other aspects of the present invention, along with the
various features of novelty that characterize the present invention, is pointed out with

particularity in the claims annexed hereto and forms a part of the present invention. For a better understanding of the present invention, its operating advantages, and the specified object attained by its uses, reference should be made to the accompanying drawings and descriptive matter in which there are illustrated exemplary embodiments of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The advantages and features of the present invention will become better
understood with reference to the following detailed description and claims taken in conjunction with the accompanying drawings, wherein like elements are identified with like symbols, and in which:
[0014] FIG. 1 illustrates a front view of abdominal signal measuring device, in
accordance with an embodiment of the present invention;
[0015] FIG. 2 illustrates a perspective view of the abdominal signal measuring device
of FIG. 1, in accordance with an embodiment of the present invention;
[0016] FIG. 3 illustrates a bottom view of the abdominal signal measuring device, in
accordance with an exemplary embodiment of the present invention;
[0017] FIG. 4 illustrates another front view of abdominal signal measuring device, in
accordance with an embodiment of the present invention;
[0018] FIG. 5 illustrates a side view of abdominal signal measuring device, in
accordance with an embodiment of the present invention;;
[0019] FIG. 6 illustrates a side perspective view of abdominal signal measuring
device, in accordance with an embodiment of the present invention;
[0020] FIG. 7 illustrates another side view of abdominal signal measuring device, in
accordance with an embodiment of the present invention;;

[0021] FIG. 8A illustrates a top view of an arm of the abdominal signal measuring
device, in accordance with an embodiment of the present invention;
[0022] FIG. 8B illustrates a bottom view of an arm of the abdominal signal measuring
device, in accordance with an embodiment of the present invention; and
[0023] FIG. 9 illustrates a front view of abdominal signal measuring device, in
accordance with an embodiment of the present invention.
[0024] Like reference numerals refer to like parts throughout the description of
several views of the drawings.
DETAILED DESCRIPTION OF THE INVENTION
[0025] For a thorough understanding of the present invention, reference is to be made
to the following detailed description, including the appended claims, in connection with the above-described drawings. Although the present invention is described in connection with exemplary embodiments, the present invention is not intended to be limited to the specific forms set forth herein. It is understood that various omissions and substitutions of equivalents are contemplated as circumstances may suggest or render expedient, but these are intended to cover the application or implementation without departing from the spirit or scope of the claims of the present invention. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of "including," "comprising," or "having" and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items.
[0026] The terms, "a" and "an" herein do not denote a limitation of quantity, but
rather denote the presence of at least one of the referenced item.
[0027] The present invention provides an abdominal signal measuring device. The
abdominal signal measuring device is designed in such a way that, the electrode orientation and distance between bipolar electrodes can be easily changed for the different belly sizes, thereby, making the application and use of the abdominal signal measuring device easy and less cumbersome, so that not only trained people but anyone with limited knowledge about

the abdominal signal measuring device can operate it in considerable less time and with considerable accuracy.
[0028] Referring now to FIG. 1, FIG. 2, FIG. 3, and FIG. 4, various views of an
abdominal signal measuring device (100). The abdominal signal measuring device (100) includes a holding member (102). The holding member (102) has a circular profile. In other embodiments of the present disclosure, the holding member (102) may have an oval, a cylindrical, or any other shape without deviating from the spirit of the present disclosure. The holding member (102) may be also referred to as a central sensor board or enclosure. The circular profile of the holding member (102) has a circumferential face, a top face (104), and an inner face (106). As would be evident to those skilled in the art that, during application of the device (100), the inner face (106) faces the patient/expectant mother, and is adapted to be places on, for example, belly of the patient/expectant mother, whereas the top face (104) is on opposite side of the inner face (102). The inner face (106) is adapted to removably receive a biocompatible adhesive. For allowing adhesion of the holding member (102) on belly of the expectant mother, for example, as shown in Figure 5. In an example, the inner face (106) of the holding member (102) includes an engraved pattern. The engraved pattern enables adhesion, and removal of the biocompatible adhesive therefrom.
[0029] The holding member (102) also includes a central, through hole (not
numbered). The hole, being at the center, may help in enabling placement of abdominal signal measuring device (100) on the abdomen considering the navel as a visual reference. The signal measuring device is used for measuring abdominal signals, ECG signals, abdominal EMG signals, Maternal ECG signals etc..
[0030] As shown in Figure 6, the abdominal signal measuring device (100) further
includes a set of arm members (200). Each of the set of arm members (200) extends outwardly from the holding member (102). Each of the set of arm members (200) comprise a body portion having a first end portion (200a) adapted to movably hold at least one sensing electrode (300), and a second end portion (200b) opposite to the first end (200a) which is connected to the holding member (102). The set of arm members (200) are positioned at a predetermined distance with respect to one another and with respect to the holding member (102). Accordingly, whereby each sensing electrode (300) continues to remain separated from corresponding sensing electrodes by at least a predetermined liner distance, and each

sensing electrode (300) continues to remain positioned, with respect to corresponding sensing electrodes, at a predetermined angular position.
[0031] In accordance with an embodiment of the present disclosure, each arm
member is composed of material elastic enough for allowing the arm members to elastically
reshape according to shape of a surface the arm member is pressed against. In an example,
each of the set of arm members (200) are embodied as straps, and may be silicone material,
Thermoplastic Polyurethane material, or Polyurethane material, and therefore are flexible. In
an example, the set of arm members (200) have a 3 mm thickness. The set of arm members
(200) provide additional support to the central sensor board enclosure during the mobility
Instead of solely relying on the adhesive used on the central sensor board enclosure. In an
example, electrodes (explained later in description) connected to the holding member (102) is
through snap wires, which may be manufactured through inserted molding, or manually
routing through the set of arm members (200). In another example, the set of arm members
(200) may be printed with the conductive ink instead of molding the cable there within
[0032] The set of arm members (200) comprises, a first arm member (202), a second
arm member (204), a third arm member (206) and a fourth arm member (208). In alternative embodiments of the present disclosure, the set of arm members (200) may provide fewer or a greater number of arm members, than four, without deviating from the spirit of the present disclosure.
[0033] More specifically, the first arm member (202) has a body portion (202c)
having a first end portion (202a) adapted to movably hold a first sensing electrode (302), and a second end portion (202b) opposite to the first end portion (202a) connected to the holding member (102). The second arm member (204) has a body portion (204c) having a first end portion (204a) adapted to movably hold a second sensing electrode (304), and a second end portion (204b) opposite to the first end portion (204a) connected to the holding member (102). The third arm member (206) has a body portion (206c) having a first end portion (206a) adapted to movably hold a third sensing electrode (306), and a second end portion opposite (206b) to the first end portion (206a) connected to the holding member (102). In an embodiment, each of the first arm member (202), the second arm member (204), and the third arm member (206) have a bulge (not numbered) in the structure, which is provided to give extra flexibility apart from the material being an elastomer. The bulge can flex inwards, depending on the physiology of the patient body.

[0034] In an embodiment, the first arm member (202), the second arm member (204),
and the third arm member (206) may be structurally identical, but positioned at different locations on the holding member (102).
[0035] As shown in Figure 7, the fourth arm member (208) has a curvilinear body
portion (208c) having a first end portion (208a) adapted to movably hold a fourth sensing electrode (308), and a second end portion (208b) opposite to the first end portion (208a) hingedly connected to the holding member (102). Each of the first arm member (202), the second arm member (204), the third arm member (205) and the fourth arm member (208) are positioned at a predetermined angular positioned with respect to each other. In an embodiment, each of the first arm member (202), the second arm member (204), the third arm member (205) and the fourth arm member (208) are positioned at an angle of 60 degree with respect to adjacent arm member.
[0036] The fourth arm member (208) further includes a fifth sensing electrode (310)
movably mounted on the curvilinear body portion (208c) thereof. In an embodiment the electrodes are removably connected to the respective arm members. Accordingly, if required, only the electrodes can be removed, disposed, and new electrodes may be attached. This reduces the cost associated with usage of the present disclosure, as only the electrodes are the disposable units.
[0037] The position of the first arm member (202) and the third arm member (206)
with respect to one another on abdominal signal measuring device (100) is such that they
define a first channel length separating the first sensing electrode (302) from the third sensing
electrode (306) by a first predetermined liner distance. In one embodiment, the first
predetermined liner distance is preset to obtain a good SNR for fECG, mECG & EHG. In an
example, the first predetermined liner distance is kept at 14.5 cm. It may herein be noted that
this linear distance between electrodes is also referred to as inter electrode distance.
[0038] In the same manner, the third arm member (206) and the fourth arm member
(208) define a fourth channel length separating the third sensing electrode (306) from the
fourth sensing electrode (308) by a fourth predetermined liner distance. In one embodiment,
the fourth predetermined liner distance is preset to obtain a good SNR for fECG, mECG &
EHG. In an example, the fourth predetermined liner distance is kept at 15.5 cm.
[0039] The first arm member (202) and the fourth arm member (208) define a third
channel length separating the first sensing electrode (302) from the fourth sensing electrode (308) by a third predetermined liner distance. Similarly, the second arm member (204) and

the fourth arm member (208) define a second channel length separating the second sensing electrode (304) from the fourth sensing electrode (308) by a second predetermined liner distance. The second predetermined linear distance and the third predetermined distance is also kept with a preferred range.
[0040] Each arm member includes one or more engagement provisions (250),
wherein engagement provisions (250) allow removable engagement of connectors of the respective sensing electrode. Specifically, as shown in Fig. 8A, each arm member, at the respective first end portion thereof, includes one or more engagement provisions (250). The engagement provisions (250) allow removable engagement of the respective sensing electrodes.
[0041] Such connection of the respective sensing electrodes on the respective arm
members, also allows angular movement, in one or more of clockwise and anticlockwise
direction, with respect to the arm member it is attached to. Specifically, as shown in Figure.
2, the first sensing electrode (302) is allowed to move in a clockwise direction along its pivot
axis, with respect to the first arm member (202). In the same manner, the second sensing
electrode (304) is allowed to move in a clockwise direction along its pivot axis, with respect
to the second arm member (204). The third sensing electrode (306) is allowed to move in a
clockwise direction along its pivot axis, with respect to the third arm member (206).
[0042] On the other hand, the fourth sensing electrode (308) is allowed to move in a
clockwise and counter-clockwise direction along its pivot axis, with respect to the fourth arm member (208).
[0043] As would be evident to those skilled in the art that exfoliation is a step to be
followed to remove the dead skin cells to get better signal reception, in other terms to increase the signal-noise ratio. Exfoliation is a step that has to be conducted at the precise location, where the electrodes are going to be placed. The arm members (200) of the present disclosure, the electrode location is easily recognized and this in turn, helps in enabling exfoliating at the right place, as shown in Figure 8. To make the skin preparation easier and on the exact location of where the electrodes are placed, the strap snap button may be considered as a reference point.
[0044] Further, a connection of the fourth arm member (208) to the holding member
(102), allows angular movement of the arm members (200) along a plane traverse to the holding member (102) whereby the fourth arm member (208) remains adapted to rest on a belly of an expectant mother. In an example, the connection of the fourth arm member (208)

to the holding member (102), is embodied as the dowel pin enabled connection. However, such example shall not be considered as limiting as in alternative embodiments of the present disclosure, various other types of connections enabling hinged movement between the fourth arm member (208) and the holding member (102) may be utilized, without deviating from the spirit of the present disclosure.
[0045] In accordance with other embodiments of the present disclosure as shown in
Figure 8A, and Figure 8B, each arm member of the abdominal signal measuring device (100) includes one or more snap fitting provisions (110), wherein the snap fitting provisions (110) allow connection of cables (not illustrated) of respective sensing electrode. The cables can be manually routed through the snap fitting provisions (110) of the arm members. In case of cable damage, the cables it can be replaced with ease, which makes the arm members reusable.
[0046] During utilizing the abdominal signal measuring device (100) of the present
disclosure, the sensor board enclosure, also referred to as the holding member (102) is firmly attached to the belly of the mother with the help of biocompatible adhesive, to make sure the abdominal signal measuring device (100) is intact without any movement, which otherwise can introduce the motion artifact noise. The arm members additionally helps in keeping the whole device firm and stay put, along with keeping the electrodes strongly attached to the belly.
[0047] The design and attachment of the electrodes with the arm members provides
the freedom to change the inter electrode distance and the angle between each channel, for better SNR on high BMI patients. The feature of changing the inter electrode distance and angle will also help during the antepartum monitoring. In special cases such as breech and transverse lie the patch design makes the application part easier, by rotating the whole patch to 180 degree, making sure the fourth electrode is at the top for breech position, and 90 degree rotation towards, right or left for monitoring the transverse lie position.

We Claim:

1. An abdominal signal measuring device (100), the device (100) comprising:
a holding member (102);
a set of arm members (200), each of the set of arm members (200) comprise a curvilinear body portion having a first end portion (200a) adapted to movably hold at least one sensing electrode (300), and a second end portion (200b) opposite to the first end (200a) connected to the holding member (102),
wherein each of the set of arm members (200) are positioned at a predetermined distance with respect to one another and with respect to the holding member (102), whereby each sensing electrode (300) continues to remain separated from corresponding sensing electrodes by at least a predetermined liner distance, and each sensing electrode (300) continues to remain positioned, with respect to corresponding sensing electrodes, at a predetermined angular position.
2. The abdominal signal measuring device (100) as claimed in claim 1, wherein the set
of arm members (200) comprises,
a first arm member (202) having a curvilinear body portion (202c) having a first end portion (202a) adapted to movably hold a first sensing electrode (302), and a second end portion (202b) opposite to the first end portion (202a) connected to the holding member (102), a second arm member (204) having a curvilinear body portion (204c) having a first end portion (204a) adapted to movably hold a second sensing electrode (304), and a second end portion (204b) opposite to the first end portion (204a) connected to the holding member (102),
a third arm member (206) having a curvilinear body portion (206c) having a first end portion (206a) adapted to movably hold a third sensing electrode (306), and a second end portion opposite (206b) to the first end portion (206a) connected to the holding member (102), and a fourth arm member (208) having a curvilinear body portion (208c) having a first end portion (208a) adapted to movably hold a fourth sensing electrode (308), and a second end portion (208b) opposite to the first end portion (208a) hingedly connected to the holding member (102), wherein each of the first arm member (202), the second arm member (204), the third arm member (205) and the fourth arm member (208) are positioned at a predetermined angular positioned with respect to each other.

3. The abdominal signal measuring device (100) as claimed in claim 2, wherein the fourth arm member (208) includes a fifth sensing electrode (310) movably mounted on the curvilinear body portion (208c) thereof, and wherein the first arm member (202) and the third arm member (206) define a first channel length separating the first sensing electrode (302) from the third sensing electrode (306) by a first predetermined liner distance.
4. The abdominal signal measuring device (100) as claimed in claim 3, wherein the third arm member (206) and the fourth arm member (208) define a fourth channel length separating the third sensing electrode (306) from the fourth sensing electrode (308) by a fourth predetermined liner distance.
5. The abdominal signal measuring device (100) as claimed in claim 4, wherein the first arm member (202) and the fourth arm member (208) define a third channel length separating the first sensing electrode (302) from the fourth sensing electrode (308) by a third predetermined liner distance.
6. The abdominal signal measuring device (100) as claimed in claim 5, wherein the second arm member (204) and the fourth arm member (208) define a second channel length separating the second sensing electrode (304) from the fourth sensing electrode (308) by a second predetermined liner distance, and wherein each arm member is composed of material elastic enough for allowing the arm members to elastically reshape according to shape of a surface the arm member is pressed against.
7. The abdominal signal measuring device (100) as claimed in claim 1, wherein each arm member includes one or more engagement provisions (250), wherein engagement provisions (250) allow removable engagement of the respective sensing electrode, and wherein hinged connection of the fourth arm member (208) to the holding member (102), allows angular movement of the arm members (200) along a plane traverse to the holding member (102) whereby the fourth arm member (208) remains adapted to rest on a belly of an expectant mother.

8. The abdominal signal measuring device (100) as claimed in claim 1, wherein the holding member (102) has a circular profile having a top face (104), and an inner face (106), the inner face (104) is adapted to removably receive a biocompatible adhesive, for allowing adhesion of the holding member (102) on belly of an expectant mother.
9. The abdominal signal measuring device (100) as claimed in claim 8, wherein the inner face (106) includes an engraved pattern enabling removal of the biocompatible adhesive therefrom, and wherein each arm member includes one or more snap fitting provisions (110), wherein the snap fitting provisions (110) allow connection of connectors of respective sensing electrode.
10. The abdominal measuring device (100) as claimed in claim 1, wherein the first end portion of each arm member is connected to respective sensing electrode such that each sensing electrode is adapted to be manually and selectively moved in one of a clockwise and anti-clockwise direction with respect to the holding member (102).