Patent Application
20190365574
The present disclosure relates to incontinence detection systems and particularly, to incontinence detection systems that use a pad beneath a person lying in a patient bed. More particularly, the present disclosure relates to incontinence detection systems that are able to communicate wirelessly between the pad and a reader on the patient bed.
Incontinence detection systems that have incontinence detection pads placed beneath a patient on a patient bed are known. For example, U.S. Pat. No. 5,537,095 discloses an incontinence detection pad having electrical circuitry that couples via a wired connection to a controller of a patient bed. Recent efforts have involved the development of wireless communication between the circuitry of the incontinence detection and a reader on a patient bed. The antennae in some such prior systems are individually powered by a reader to energize a passive RFID chip on the incontinence detection pad and to read backscattered data sent from the passive RFID chip back to the reader via the antennae.
In the known wireless incontinence detection pad systems, signal to interfere (S/I) ratio issues are prevalent. For example, when a monostatic architecture using a hybrid directional coupler to provide receiver isolation from the transmitter and to allow simultaneous transmission and reception on the same antenna, the coupling between the transmitter and receiver ports of the hybrid coupler is about −10 decibels (dB). This means that 90% of the received signal does not end up in the receiver. Furthermore, if the antenna impedance deviates from the transmission line characteristic impedance, the power reflected from the antenna is coupled into the receiver input and is much stronger than the backscattered signal from the RFID tag, which creates the situation where the receiver must reject a very strong signal near the signal of interest in order to detect and demodulate only the signal of interest, which in the case of an EPC 2 compliant tag, is 256 kilohertz (kHz) away from the carrier. In such situations the S/I ratio can be on the order of 50 dB. An alternative known architecture is the use of a circulator which couples the transmitter and receiver, functionally, in a similar way as a hybrid coupler. However, the S/I ratio using a circulator is only about 1.6 dB better than the hybrid coupler approach.
Other interfering signals include forward power coupling into the receiver port, which can be 5 dB higher than the tag backscattered signal, and power reflected from the RF forward power, which can be 34 dB stronger than the backscattered signal. All of these signals add into the front end of the receiver, which subjects it to overload and intermodulation distortion products which may further impact the performance of the receiver. In other words, because there is a strong signal close in frequency to a weak signal, it is difficult to detect the weak signal. A further concern is that RFID systems that are located in close proximity to a patient's body experience communication channel degradation due to the interaction of the biological tissue and body fluids with the RFID tag.
Based on the foregoing, it should be apparent that there is an ongoing need for improved electrical architecture in wireless incontinence detection pad systems used on patient support apparatuses such as patient beds. It will also become apparent that there is a need to provide an incontinence detection system for use in settings in which the expense of a purchasing or renting a hospital grade bed is not justified.
The present application discloses one or more of the features recited in the appended claims and/or the following features which, alone or in any combination, may comprise patentable subject matter:
According to the present disclosure, an incontinence detection system may include an incontinence detection pad for placement beneath a person to be monitored. The incontinence detection pad may have a passive radio frequency identification (RFID) tag. A reader may be provided and a plurality of antennae may be coupled to the reader. The reader may include a bistatic radio frequency (RF) switch matrix which may be operable to establish a first antenna of the plurality of antennae as a transmit antenna that may be used to wirelessly energize the passive RFID tag and to establish a second antennae of the plurality of antennae as a receive antenna that may be used to read backscattered data that may be emitted from the passive RFID tag. The first and second antennae may be situated in respective housings that are spaced apart from each other.
In some embodiments, the plurality of antennae may include a third antenna and a fourth antenna. The bistatic RF switch matrix may be operated in a full cycle scanning mode so that each of the first, second, third and fourth antenna may be selectively chosen to be established as the transmit antenna and each of the remaining antenna may be selectively cycled through to be the receive antenna such that twelve transmit antenna and receive antenna combinations may be operated.
During the full cycle mode, the transmit antenna and receive antenna combinations that may produce valid reads of the RFID tag may be stored. A modified cycle scanning mode then may be determined for operation of the bistatic RF switch matrix based on the valid reads such that only transmit antenna and receive antenna combinations that produced valid reads may be cycled through for a predetermined number of cycles, after which the bistatic RF switch matrix may be once again operated in the full cycle scanning mode. If no valid reads of the passive RFID tag are detected during the full cycle scanning mode, then the bistatic RF switch matrix may continue to operate in the full cycle scanning mode until at least one valid read is detected, after which the bistatic RF switch matrix may be operated in the modified cycle scanning mode.
In some embodiments, the plurality of antennae may be operated by the reader by transmitting using a frequency hopping scheme at a power less than or equal to 1 Watt (W). The frequency hopping scheme may use 50 distinct frequencies, for example, with each frequency being used only once in a pseudo-random order before any of the 50 frequencies may be repeated. Optionally, the 50 frequencies may lie within a range between about 902 MegaHertz (MHz) and 928 MHz. At least one antenna of the plurality of antennae may comprise a ½ wave ceramic patch antenna. If desired, however, each antenna of the plurality of antennae may comprise a ½ wave ceramic patch antenna.
The incontinence detection system may further include a patient bed that may have a frame and a mattress support deck that may be carried by the frame. The mattress support deck may include a head section, a seat section, and a thigh section. At least the head section and the thigh section may be raiseable and lowerable relative to the frame. The first and second antennae may be coupled to the head section, the third antenna may be coupled to the seat section, and the fourth antenna may be coupled to the thigh section. Alternatively, the first antenna may be coupled to the head section, the second and third antennae may be coupled to the seat section, and the fourth antenna may be coupled to the thigh section. Further alternatively, the first antenna may be coupled to the head section, the second antenna may be coupled to the seat section, and the third and fourth antennae may be coupled to the thigh section.
In some embodiments, the incontinence detection may further include a patient bed that may have a frame and a mattress support deck carried by the frame. The mattress support deck may include a first section and a second section that each may be raiseable and lowerable relative to the frame. The first section and the second section each may be formed in a step deck arrangement that may have a bottom wall and a side wall that may extend generally upwardly from the bottom wall. The first antennae may be coupled to the bottom wall of the first section, the second antenna may be coupled to a side wall of the first section, the third antenna may be coupled to the bottom wall of the second section, and the fourth antenna may be coupled to the side wall of the second section.
It is within the scope of this disclosure that the incontinence detection system may further include a patient bed that may have a frame and a mattress support deck carried by the frame. The reader may be coupled to the frame and the plurality of antennae may be coupled to the mattress support deck so as to be closer to a first side of the mattress support deck than an opposite second side of the mattress support deck.
In some embodiments, the incontinence detection system may further include an indicator that may be located adjacent a foot end of the bed and that may be operable to indicate that an incontinence event has occurred. Optionally, an output port may be located adjacent a head end of the bed and may be connectable to a nurse call system for providing incontinence event data to the nurse call system.
According to the present disclosure, an electrical sheet for an incontinence detection pad may be provided. The electrical sheet may include a layer of material that may be shaped generally as a rectangle that may have first and second long sides and first and second short sides. An RFID tag may be coupled to the layer closer to the first short side than the second short side. First and second electrodes may be provided on the layer and may be electrically coupled to the RFID tag. The first and second electrodes may include first, second, third and fourth electrode segments that may be generally parallel with the first and second long sides of the layer. The second and third electrode segments may be situated between the first and fourth electrode segments. The second and third electrode segments may be spaced apart by a first distance that may be at least twice a second distance that may be defined between the first and second electrode segments and between the third and fourth electrode segments.
The first and second electrodes may also provide fifth, sixth, seventh and eighth electrode segments that may be generally parallel with the first and second short sides of the layer. The sixth and seventh electrode segments may be situated between the fifth and eighth electrode segments. The fifth and sixth electrode segments may be spaced apart by a third distance that may be at least six times a fourth distance that may be defined between the fifth and sixth electrode segments and between the seventh and eighth electrode segments.
The fifth and seventh electrode segments may be included as part of the first electrode and the sixth and eighth electrode segments may be included as part of the second electrode. The first and third electrode segments may be included as part of the first electrode and wherein the second and fourth electrode segments may be included as part of the second electrode. The layer may be devoid of any electrode portions between the second and third electrode segments.
In some embodiments, the first distance between the second and third electrode segments may be greater than 30% of a third distance that may be defined between the first and second long sides of the layer. For example, the first distance between the second and third electrode segments may be greater than 40% of a third distance that may be defined between the first and second long sides of the layer. The spacing between the second and third electrode segments is intended to be sufficiently large to prevent a gel or ointment applied to a patient's buttocks and/or sacral region from providing an electrically conductive path between the second and third electrode segments that are oriented parallel with the first and second long sides of the layer.
According to a further aspect of this disclosure, an electrical sheet for an incontinence detection pad is provided. The electrical sheet may include a layer of material shaped generally as a rectangle having first and second long sides and first and second short sides. An RFID tag may be coupled to the layer closer to the first short side than the second short side. First and second electrodes may be provided on the layer and may be electrically coupled to the RFID tag. The first and second electrodes may include first, second, third and fourth electrode segments that may be generally parallel with the first and second short sides of the layer. The second and third electrode segments may be situated between the first and fourth electrode segments. The second and third electrode segments may be spaced apart by a first distance that may be at least six times a second distance that may be defined between the first and second electrode segments and between the third and fourth electrode segments.
The layer may be devoid of any electrode portions between the second and third electrode segments. The first distance between the second and third electrode segments may be greater than 50% of a third distance defined between the first and second short sides of the layer. The spacing between the second and third electrode segments is intended to be sufficiently large to prevent a gel or ointment applied to a patient's buttocks and/or sacral region from providing an electrically conductive path between the second and third electrode segments that are oriented parallel with the first and second short sides of the layer.
In some embodiments, the electrical sheet may further have at least one icon that may include a water droplet with WiFi curves and that may be printed on a surface of the layer that may be opposite from a surface on which the first and second electrodes may be provided. Optionally, the layer may include a first substrate that may be made of a fluid impermeable material and a second substrate that may be made of a nonwoven material. The first and second electrodes may be located on the fluid impermeable material and the at least one icon may be located on the nonwoven material.
For each of the above aspects and embodiments contemplated herein, a reader of an incontinence detection system may be equipped with an 802.11 wireless communication capability for communication with a wireless access point which may, in turn, be connected via a network to a remote computer, such as a remote computer or server of a Clinical Workflow Solutions (CWS) medical data management system. The CWS system may or may not be included as part of nurse call system, for example. The reader may send tag identification (ID) and an encrypted ID, both of which may be received by the reader from a RFID tag of an incontinence detection pad, to the remote server of the CWS system for remote validation of the incontinence detection pad that may be placed on a bed. More than one pad may be placed on the bed 10 in which case the reader may receive more than one tag ID and more than one encrypted ID. The CWS system may perform decryption remotely and may compare the tag ID and the data that may be derived from decrypting the encrypted ID from the tag to complete the validation. If desired, the data sent from the reader may be protected against transmission errors corrupting the data with standard Internet Protocol error checking algorithms and/or additional error detection that may be applied by the reader at the bed.
By moving the validation operation to a remote site, such as a computer or server of CWS system that may have internet connectivity may result in a number of advantages. Firstly, the processor of the reader at the bed may not have the computational resources either in terms of memory or CPU cycles to accomplish the decryption locally. Secondly, the encryption algorithm may be changed at will and the algorithm that may be used may be determined by tag ID so the deployment in the field may be seamless. The encryption details and private keys may be managed by an online connection to a secure server at another facility (e.g., a server at the entity which may manufacture or sell the incontinence detection system and/or the bed), which may enable the modification of the private key on an as-needed basis, a periodic change in private key or the wholesale replacement of the encryption algorithm in a secure fashion. In this way, the data generated for pad validation may be done in an entirely secure fashion, and may be done on an as needed basis. If it is detected that the private key has become compromised, a new private key may be instituted and the pad serial numbers/private key may be maintained in a database at the CWS server for pad validation.
In some embodiments, the incontinence detection systems and the bed may be used in home healthcare and other markets outside a traditional hospital or other healthcare facility. For such markets, the reader may be constructed with a very limited functionality microprocessor by having the high compute resource intensity operations, such as decryption algorithms, accomplished remotely via any available internet connection. As a collateral benefit, a service may be used to automatically bill and send more incontinence pads to a customer (via prior arrangement), thereby enabling e-commerce business using existing hardware connections. Thus, a server of the CWS system or a server at a remote facility may perform pad usage data collection, may perform billing functions, and/or may generate inventory management data, as well as provide other notifications to hospitals or home users about incontinence detection pad usage. For example, such usage data may include a number of pads used per day, week, and/or month; average amount of time before a dry pad becomes soiled; average amount of time after soiling before the wet pad is removed and/or replaced with a dry pad; and number of pads remaining from prior shipment quantity for usage.
Additional features, which alone or in combination with any other feature(s), including those listed above and those listed in the claims, may comprise patentable subject matter and will become apparent to those skilled in the art upon consideration of the following detailed description of illustrative embodiments exemplifying the best mode of carrying out the invention as presently perceived.
The detailed description particularly refers to the accompanying figures in which:
Referring now to
With the exception of bed 10 of
Reader 12 is operated so that a selected one of antennae 13, 14, 15, 16 is established as a transmit antenna and another of antennae 13, 14, 15, 16 is established as a receive antenna. As will be described in further detail below, reader 12 is operated to cycle through each antennae 13, 14, 15, 16 as being the transmit antenna and to cycle through the remaining three antennae, one at a time, as being the receive antenna. The transmit antenna emits wireless energy to power an RFID chip of RFID tag 64 and, in response, the RFID tag transmits backscattered data which is potentially read by the receive antenna. The data indicates whether the pad 60 is wet or dry. The pad 60 is considered “wet” if there is enough moisture or liquid, such as incontinence, to bridge a space between the electrode traces and the pad 60 is considered “dry” if there is insufficient moisture or liquid to bridge the space between the electrode traces.
Bed 10 of
Bed 10 of
In the illustrative
In the illustrative
Bed 10 of
Bed circuitry 72 is operable to output bed data, including data detected by the incontinence detection system 20, through a nurse call output port 80 shown diagrammatically in
Each antenna 13, 14, 15, 16 is smaller than the two antennae disclosed in International Patent Application No. PCT/US2016/062167, filed Nov. 16, 2016, titled “Incontinence Detection Systems for Hospital Beds,” and owned by the same Assignee as the present application. A footprint of each antenna 13, 14, 15, 16 is about three inches by three inches. Furthermore, each antenna 13, 14, 15, 16 comprises a ½ wave ceramic patch antenna. This type of antenna is an improvement over the antenna disclosed in International Patent Application No. PCT/US2016/062167. In particular, about 25 to about 30 dB of isolation is achieved by using the ½ wave ceramic patch antenna as part of antennae 13, 14, 15, 16 which represents better isolation by about 15 to about 25 dB as compared to a directional coupler design. This is because the reflected power signal back from the transmit antenna is no longer coupled into the receiver of reader 12. The receiver circuitry of reader 12 is isolated from the transmitter circuitry.
Referring now to
As shown in
Antennae 13, 14 of
The reason for locating antennae 13, 14, 15, 16 closer to the left side of bed 10 is twofold. First, the thickness of each antenna 13, 14, 15, 16 is in the range of about ½ inch, give or take a ¼ inch or so, and therefore, by placing the antennae 13, 14, 15, 16 closer to the left side of deck 30, a patient positioned on a mattress supported by deck 30 is less likely to “feel” the antennae 13, 14, 15, 16 through the mattress. Second, incontinence detection pads 60 contemplated by this disclosure have RFID tags 64 situated near the left side of the pads 60. Thus, the antennae 13, 14, 15, 16 which emit or radiate energy to power the RFID tags 64 and to read the data sent or reflected back from the RFID tags 64 operate more efficiently when they are closer to the RFID tags 64. Accordingly, it should be appreciated that, in alternative embodiments of incontinence detection system 20, antennae 13, 14, 15, 16 may be located closer to the right side of bed 10 if the incontinence pads 60 of such alternative embodiments have their respective RFID tags 64 situated near the right sides of the pads 60 rather than the left sides. Alternatively or additionally, deck sections 32, 34 may be formed with recesses in which respective antennae 13, 14, 15, 16 are received so that upper surfaces of antennae 13, 14, 15, 16 are generally flush with upper surfaces of the bottom panel of deck sections 32, 34.
In the embodiment of
Cable 25 is routed from reader 12 to visual indicator 1118 along an underside of thigh section 34 and foot section 36 as shown in
Suitable cable management devices such as zip ties, hooks, clips, straps, bands, and the like are provided in some embodiments to attach cables 23, 25, 27 to portions of bed 10 at various locations to prevent unwanted sagging or movement of cables 23, 25, 27. However, as suggested above, some portions of cables 23, 25, 27 should be sufficiently slack to permit movement of the various portions of bed 10 without stretching, pinching or binding the respective cable 23, 25, 27. Reader 12 of
Referring now to
Deck 30 of
In some embodiments, a pivot axis about which head section 32 of bed 10 of
A seat section 33 of deck 30 of bed 10 can be seen in
In the illustrative example of
Foot section 36 of bed 10 of
Referring now to
A head section motor 90 for pivotably raising and lowering head section 32 and a thigh section motor 92 for pivotably raising and lowering thigh section 34, such as through flanges, brackets, and/or linkages attached to frame 38 and sections 32, 34, are shown diagrammatically in
As indicated diagrammatically in
If reader 12 determines that pad 60 is wet, a second bit (aka a kill bit) is set in RFID tag 64 by reader 12 via the established transmit antennae 13, 14, 15, 16. Once the kill bit is set in RFID tag 64, it remains unchanged thereafter. If pad 60 dries out after having been wet, reader 12 will see that the kill bit is still set when it receives subsequent data from RFID tag 64 such that the particular pad 60 should not be re-used. In some embodiments, reader 12 sends an alert to indicate that the pad 60 is a “bad” pad that should not be used because it has been previously soiled with wetness. In other embodiments, reader 12 simply causes visual indicator 18 to emit white light indicating that a “good” pad is not being read by the reader 12.
If desired, caregivers may place multiple pads 60 on mattress 100 beneath the patient. For example, it is not uncommon for two pads 60 to be used to increase the area of incontinence absorption beneath a patient. The reader 12 is able to read backscattered data from multiple RFID tags 64 of multiple pads 60 according to this disclosure. Some transmit/receive antennae combinations, for example, may read one RFID tag 64 and other transmit/receive antennae combinations may read another RFID tag 64, for example. Some transmit/receive antennae combinations may read multiple tags 64. Reader 12 initiates an alert, as described elsewhere herein, if any one or more of the multiple incontinence detection pads 60 indicate that they are wet.
As further indicated diagrammatically in
As shown diagrammatically in
In some embodiments contemplated herein, reader 12 of incontinence detection system 20 is equipped with an 802.11 wireless communication capability for communication with wireless access point 118 which is, in turn, connected via network 120 to a remote computer or server of a Clinical Workflow Solutions (CWS) medical data management system 122. CWS system 122 may or may not be included as part of nurse call system 122. Block 122 in
By moving the validation operation to a remote site, such as a computer of CWS system 122, having internet connectivity results in a number of advantages. Firstly, the processor of reader 12 at the bed 10 may not have the computational resources either in terms of memory or CPU cycles to accomplish the decryption locally. Secondly, the encryption algorithm can be changed at will and the algorithm used determined by tag ID so the deployment in the field is seamless. The encryption details and private keys may be managed by an online connection to a secure server at another facility (e.g., a server at the entity which manufactures or sells system 20 and/or bed 10), which enables the modification of the private key on an as-needed basis, a periodic change in private key or the wholesale replacement of the encryption algorithm in a secure fashion. In this way, the data generated for pad validation is done in an entirely secure fashion, and may be done on an as needed basis. If it is detected that the private key has become compromised, a new private key may be instituted and the pad serial numbers/private key maintained in a database at the CWS server 122 for pad validation.
System 20 and bed 10 may be used in home healthcare and other markets outside a traditional hospital or other healthcare facility. For such markets, the reader 12 may be constructed with a very limited functionality microprocessor by having the high compute resource intensity operations, such as decryption algorithms, accomplished remotely via any available internet connection. As a collateral benefit, a service is contemplated to automatically bill and send more incontinence pads to a customer (via prior arrangement), thereby enabling e-commerce business using existing hardware connections. Thus, a server of CWS system 122 or a server at a remote facility may perform pad usage data collection, may perform billing functions, and/or may generate inventory management data, as well as provide other notifications to hospitals or home users about incontinence detection pad 60 usage. For example, such usage data may include number of pads 60 used per day, week, and/or month; average amount of time before a dry pad becomes soiled; average amount of time after soiling before the wet pad is removed and/or replaced with a dry pad; and number of pads remaining from prior shipment quantity for usage.
In some embodiments, such as the illustrative embodiments of
In some embodiments, reader 12 energizes antennae 13, 14, 15, 16 to scan for RFID tag 64 using a linear frequency hopping scheme that cycles through fifty frequencies between a lower frequency limit and an upper frequency limit. In some embodiments, the lower frequency limit is about 902 Megahertz (MHz) and the upper frequency limit is about 928 MHz. The frequency hopping scheme is non-consecutive and the hops are arranged in groups of five that start near the bottom of the frequency band and hop in approximately 5 Megahertz (MHz) jumps to near the top of the frequency band, then the hops go back near the bottom of the frequency band until all fifty frequencies are used. No frequency is used twice until all fifty frequencies have been used, at which time the sequence restarts. In some embodiments, the sequence of frequencies is as follows: 902.75; 907.75; 912.75; 917.75; 922.75; 906.75; 911.75; 916.75; 921.75; 926.75; 904.75; 909.75; 914.75; 919.75; 924.75; 903.25; 908.25; 913.25; 918.25; 923.25; 907.25; 912.25; 917.25; 922.25; 927.25; 905.25; 910.25; 915.25; 920.25; 925.25; 903.75; 908.75; 913.75; 918.75; 923.75; 905.75; 910.75; 915.75; 920.75; 925.75; 904.25; 909.25; 914.25; 919.25; 924.25; 906.25; 911.25; 916.25; 921.25; and 926.25. However, it should be appreciated that other sequences of fifty frequencies may be used in the frequency hopping scheme in other embodiments. In some embodiments, the sequence of fifty frequency hops is set arbitrarily by software.
As discussed above, each antenna 13, 14, 15, 16 is cycled through as being the transmit antenna and each of the remaining three antennae 13, 14, 5, 16 are cycled through as being the receive antenna. In this regard, the following twelve transmit and receive antenna combinations are provided in some embodiments: antenna 13 transmits and antenna 14 receives, followed by antenna 16 receives, followed by antenna 16 receives; antenna 14 transmits and antenna 13 receives, followed by antenna 15 receives, followed by antenna 16 receives; antenna 15 transmits and antenna 13 receives, followed by antenna 14 receives, followed by antenna 16 receives; and antenna 16 transmits and antenna 13 receives, followed by antenna 14 receives, followed by antenna 15 receives. In this scenario, there is only one transmit antenna and one receive antenna at any given instance during operation of reader 12. In each case, reader 12 uses the next available frequency in the hopping sequence when cycling through the transmit and the receive antennae combinations.
In the illustrative example, a multiple input multiple output (MIMO) antenna control scheme is not used because only one antenna transmits at any given time and only one other antenna is established as the receive antenna at any given time. However, it is within the scope of this disclosure for multiple output antennae (i.e., multiple transmit antennae that transmit substantially simultaneously) and/or multiple input antennae (i.e., multiple receive antennae that are established as receive antennae) to be established by reader 12 in other embodiments. For example, antennae 13, 14 may be established by reader 12 as transmit antenna and antennae 15, 16 may be established by reader 12 as receive antennae. All 2-by-2 combinations of antennae 13, 14, 15, 16 are contemplated. Alternatively, three of antennae 13, 14, 15, 16 may be established as transmit antennae and the remaining one antenna 13, 14, 15, 16 may be established as the receive antenna. All 3-by-1 combinations of antennae 13, 14, 15, 16 are contemplated. Further alternatively, one of antenna 13, 14, 15, 16 may be established as the transmit antennae and the remaining three antenna 13, 14, 15, 16 may be established as receive antennae. All 1-by-3 combinations of antennae 13, 14, 15, 16 are contemplated. In some embodiments, incontinence detection system 20 may have only three antennae or may have more than four antennae. All permutations and combinations of receive and transmit antennae designations are contemplated by this disclosure.
As shown in
According to this disclosure, the bistatic RF switch matrix 140 is operated in a full cycle scanning mode so that each of the first, second, third and fourth antenna 13, 14, 15, 16 is selectively chosen to be established as the transmit antenna and each of the remaining three antenna are selectively cycled through to be the receive antenna such that twelve transmit antenna and receive antenna combinations are operated. During the full cycle scanning mode, the transmit antenna and receive antenna combinations that produce valid reads of one or more RFID tags 64 of respective one or more incontinence detection pads 60 that are bed 10 are stored. In some embodiments, a modified cycle scanning mode is then determined for operation of the bistatic RF switch matrix 140 based on the valid reads such that only transmit antenna and receive antenna combinations that produced valid reads of the one or more RFID tags 64 are cycled through for a predetermined number of cycles, after which the bistatic RF switch matrix 140 is once again operated in the full cycle scanning mode.
The full cycle scanning mode may operate for several iterations so that, for example, ten reads of all possible antenna 13, 14, 15, 16 transmit/receive combinations are made before determining those combinations to be used in the modified cycle scanning mode. The predetermined number of iterations of the modified cycle scanning mode may be more or less than ten, for example. During the modified cycle scanning mode, the frequency hopping scheme described above continues to be used, just on a lesser number of transmit and receive antennae 13, 14, 15, 16 combinations. In some embodiments, if no valid reads of the passive RFID tag 64 are detected during the full cycle scanning mode, then the bistatic RF switch matrix 140 continues to operate in the full cycle scanning mode until at least one valid read is detected, after which the bistatic RF switch matrix 140 is operated in the modified cycle scanning mode.
Antennae 13, 14, 15, 16 of reader 12 are operated at low power (e.g., less than or equal to 1 Watt) to meet U.S. Federal Communications Commission (FCC) regulations for maximum permissible exposure (MPE) limits. The MPE limits specified by the FCC are dependent upon frequency and power density limits which are specified as an average value over a six minute period. In the 902 MHz-928 MHz frequency band, the power density limit is 0.601 milliWatts (mW)/cm2 over any six minute period of time. In some embodiments, a delay period is provided between transmissions from antennae 13, 14, 15, 16 to keep within the MPE limits.
Referring now to
Electrode 202 has a first straight line segment portion 206, a second straight line segment portion 208 that is substantially perpendicular to portion 206, a third straight line segment portion 210 which is substantially perpendicular to second portion 208 and which couples to RFID tag 64, a fourth straight line segment portion 212 that is substantially parallel with portion 208, a fifth straight line segment portion 214 which is parallel with portions 206, 210, a sixth straight line segment portion 216 which is parallel with portions 208, 212, and a seventh straight line segment portion 218 which is parallel with portions 206, 210, 214 and aligned with portion 206. The transitions between portions 206, 208, 210, 212, 214, 216, 218 are rounded such as having a radius of about 51.5 mm, although the radius between portions 208, 210 is about 36.5 mm and the radius between portions 210, 212 is even less than that. The rounded portions of trace 202 each extend over an arc of about 90°.
Electrode 204 has a first straight line segment portion 220, a second straight line portion 222 that is substantially perpendicular to portion 220, a third straight line segment portion 224 that extends from portion 222 in perpendicular relation therewith, a fourth straight line segment portion 226 that is substantially parallel with portion 220, a fifth straight line segment portion 228 that is substantially parallel with portion 226 and offset therefrom, and a sixth straight line segment portion 230 that, when extended, forms an included angle 232 of about 45° with portion 226. Portion 230 provides and inclined transition between portions 226, 228. Portion 228 also couples electrically with RFID tag 64. The transition between portion 220 and portion 222 and the transition between portion 224 and portion 226 is rounded over an arc of about 90° such as having a radius about 51.5 mm.
Portion 206 of trace 202 is substantially parallel with, and situated between, portions 220, 226 of trace 204. Portion 226 of trace 204 is substantially parallel with, and situated between, portions 206, 214 of trace 202. Similarly, portion 208 of trace 202 is substantially parallel with, and situated between, portions 222, 224 of race 204. Portion 224 of trace 204 is parallel with, and situated between, portions 208, 216 of trace 202. Electrodes 202, 204 are printed on backsheet 200 and comprise a conductive ink such as carbon ink, silver ink, or the like. In some embodiments, the thickness of traces 202, 204 is about 3.0 mm+/−0.5 mm.
Perpendicular distances 234 between portion 206 of electrode 202 and portion 220 of electrode 204 and between portion 214 of electrode 202 and portion 226 of electrode 204 is about 127.0 mm in the illustrative example. A perpendicular distance 236 between portion 206 of electrode 202 and portion 226 of electrode 204 is about 317.0 mm in the illustrative example. Thus, the distance 236 between portions 206, 226 is more than twice that of each of distances 234. In particular, the ratio of distance 236 to 234 is about 317/127=2.496.
Perpendicular distances 238 between portion 208 of electrode 202 and portion 222 of electrode 204 and between portion 216 of electrode 202 and portion 224 of electrode 204 is about 77.0 mm in the illustrative example. A perpendicular distance 240 between portion 208 of electrode 202 and portion 224 of electrode 204 is about 537.0 mm in the illustrative example. Thus, the distance 240 between portions 208, 224 is more than six times that of each of distances 238. In particular, the ratio of distance 236 to 234 is about 537/77=6.974.
Long side edges 242 of backsheet 200 have lengths of about 900.0 mm and short end edges 244 have lengths of about 750.0 mm in the illustrative example. The long dimension of backsheet 200 is sometimes referred to as the machine direction (MD) and the short dimension of backsheet 200 is sometimes referred to as the cross direction (CD). Distance 236 between the electrode segment portions 206, 226 is greater than 30% and greater than 40% of the 750.0 mm distance defined between the long sides 242 of the layer 200. In particular, the ratio of distance 236 to 750.0 mm is 317/750=0.423 or 42.3% on a percentage basis. Distance 240 between the electrode segment portions 208, 224 is greater than 40% and greater than 50% of the 900.0 mm distance defined between the short ends 242 of the layer 200. In particular, the ratio of distance 240 to 900.0 mm is 537/900=0.597 or 59.7% on a percentage basis.
Distances 236 between electrode portions 206, 226 and distance 240 between electrode portions 208, 224 provide the incontinence detection pad 60 having backsheet 200 with a relative large central region that is devoid of any electrode portions. This represents an improvement over the electrode trace geometry of the incontinence detection pad disclosed in International Patent Application No. PCT/US2016/062167, particularly in connection with
Backsheet 200 includes a sacrificial trace 246 in an end region adjacent to one of edges 244. Sacrifical trace 246 is left over from an electrode trace of a next adjacent backsheet 200 during a manufacturing process as is described in further detail in International Patent Application No. PCT/US2016/062167, particularly in connection with
Still referring to
The beds of
The incontinence detection system also includes an off-board RFID reader 350. The reader includes circuitry 352 analogous to that of
The incontinence detection system also includes an off-board antenna array 370 having at least one antenna member. The illustrated antenna array includes four antennas 370A, 370B, 370C, 370D. Each member of antenna array 370 is adapted to communicate with reader 12 by way of a cable 23. The term “off-board” used in connection with the antenna array means that unlike the antennas of
As seen in
Reader 350 is adapted to communicate with a destination device, either wirelessly or by way of a wired connection. For simplicity, the destination device may be referred to herein as a destination. In one embodiment the reader is equipped with an IEEE 802.11 wireless communication capability for communication with the destination. Other wireless protocols may also be satisfactory. The destination is a device configured or configurable to receive information from the reader and to display the information to a user or to provide the information to a display unit that responds by displaying the information. The information is information related to possible incontinence events, such as whether an incontinence event has occurred. Other useful information may include frequency of incontinence events and response time of a caregiver, to name just two.
In some cases the destination device is configured to or is configurable to receive information from two or more readers and to associate the information displayed on the display with a single one of the readers from which the information originated. For example
The nurses' station is equipped with a destination device such as an information display monitor 390. The monitor is configurable to receive information from all the readers and to associate the displayed information with the reader that was the source of that information.
As already noted, the reader and antenna array of
In one embodiment the incontinence detection system may also include an indicator 400 which is the destination to which the reader communicates. The indicator issues an audible and/or visual alert when the incontinence pad is in a state consistent with a person having experienced an incontinence event, i.e. when moisture or liquid bridge the space between the electrode traces 306, 308. The illustrated indicator is a unit having three indicator lights. One light glows when reader 350 determines that a pad is not present on the bed; another glows when the reader determines that a pad is present and dry; the third light glows when the reader determines that a pad is present and wet.
The indicator, like the reader and antenna array, is “off-board” That is, it is not built in to the bed. Nevertheless it may be equipped with a hook 398 (and is illustrated as so equipped) or other mounting device so that the indicator can be mounted on the bed or other convenient host by the user.
The destination may also be a mobile communication device. A mobile communication device is a device that is typically used by a single person at a time and that the person frequently carries with him. Examples include a mobile phone or a small personal computer that the person carries with him. In some cases two or more people may carry the mobile communication device at different times. For example if two members of a household share caregiving duties for a loved one in the household, each may carry the device when he or she is “on duty” Such sharing among caregivers does not defeat the device's status as a personal device.
The destination may also be a fixed communication device. In contrast to a mobile device, a fixed device is not readily portable, as is the case with a mobile telephone or a small computer. A fixed device is one that a person would not routinely carry with him. One example is a monitor (e.g. monitor 390 of
As seen in
The chassis mounted arrangement, like the discrete arrangement, is “off-board” by reason of not being built-in to the bed. However as seen in
Because the reader and antennas are not built-in features of a costly hospital grade bed, the incontinence detection system is portable and may be easily, conveniently, and inexpensively deployed in non-hospital settings. The user places one or more pads on the person support surface and places the antennas and reader at any convenient place, for example on the floor underneath the bed, on a table, or on a dresser. Placement of the reader relative to the pad is subject only to the constraints that the reader must be able to interrogate the pad and receive usable signals from it.
The off-board incontinence detection system has thus far been described in the context of its operational environment. The system can also be described in terms of a kit as shipped by its manufacturer or distributor and as received by its recipient.
Referring back to
Alternatively, one or more incontinence pads may be included as part of the kit instead of being a separately acquired component.
The kit comprised of the reader 350 and antenna array 370, and the kit comprised of the reader 350, antenna array 370, and incontinence 302 pad may also include an “indicator” 400.
In one embodiment the kit includes at least the reader 350 and antenna array 370 mounted on a chassis 410 as seen in
Although certain illustrative embodiments have been described in detail above, variations and modifications exist within the scope and spirit of this disclosure as described and as defined in the following claims.
The present application is a continuation-in-part of U.S. patent application Ser. No. 15/596,036 entitled “Incontinence Detection Apparatus Electrical Architecture” filed on May 16, 2017, which is a continuation in part of International Application No. PCT/US2016/062167, which was filed Nov. 16, 2016, which claims the benefit, under 35 U.S.C. § 119(e), of U.S. Provisional Application No. 62/255,592, which was filed Nov. 16, 2015, and each of which is hereby incorporated by reference herein in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 62255592 | Nov 2015 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 15596036 | May 2017 | US |
| Child | 16504654 | US | |
| Parent | PCT/US2016/062167 | Nov 2016 | US |
| Child | 15596036 | US |
