Patent Publication Number: US-2022217474-A1

Title: Ear-worn electronic device configured to compensate for hunched or stooped posture

Description:
TECHNICAL FIELD 
     This application relates generally to ear-worn electronic devices, including hearing devices, hearing aids, personal amplification devices, and other hearables. 
     BACKGROUND 
     Hearing devices provide sound for the wearer. Some examples of hearing devices are headsets, hearing aids, speakers, cochlear implants, bone conduction devices, and personal listening devices. For example, hearing aids provide amplification to compensate for hearing loss by transmitting amplified sounds to a wearer&#39;s ear canals. Hearing devices can include components which are orientation-dependent and designed for optimal operation when worn by a wearer having normal posture. Suboptimal performance results when a hearing device with orientation-dependent components is worn by a user with hunched or stooped posture. 
     SUMMARY 
     Embodiments are directed to a method implemented by an ear-worn electronic device situated in, on, or about an ear of a wearer. The method comprises sensing an angular position of the device relative to a horizontal plane oriented orthogonal to a direction of gravity, the angular position of the device substantially corresponding to an orientation of the wearer&#39;s head relative to the horizontal plane, a longitudinal plane orthogonal to the horizontal plane, and a frontal plane orthogonal to the horizontal plane and the longitudinal plane. The method also comprises detecting a change in the angular position of the device from a first angular position to a second angular position, the first angular position corresponding to a specified angular position that provides for a target or optimal level of device performance and the second angular position resulting in suboptimal device performance. The method further comprises implementing, by the device, a corrective action that improves performance of the device relative to the suboptimal device performance while operating the device at the second angular position. For example, the corrective action can improve device performance from suboptimal device performance to about the target or optimal level when operating the hearing device at the second angular position. 
     Embodiments are directed to an ear-worn electronic hearing device configured for use in, on, or about an ear of a wearer. The device comprises a processor operatively coupled to memory, a speaker or a receiver operatively coupled to the processor, and one or both of a microphone arrangement and a telecoil arrangement operatively coupled to the processor. A sensor is operatively coupled to the processor and configured to sense an angular position of the device relative to a horizontal plane oriented orthogonal to a direction of gravity, the angular position of the device substantially corresponding to an orientation of the wearer&#39;s head relative to the horizontal plane, a longitudinal plane orthogonal to the horizontal plane, and a frontal plane orthogonal to the horizontal plane and the longitudinal plane. The processor is configured to detect a change in the angular position of the device from a first angular position to a second angular position, the first angular position corresponding to a specified angular position that provides for a target or optimal level of device performance and the second angular position resulting in suboptimal device performance. The processor is also configured to implement a corrective action that improves performance of the device relative to the suboptimal device performance while operating the device at the second angular position. For example, the corrective action can improve device performance from suboptimal device performance to about the target or optimal level when operating the hearing device at the second angular position. 
     The above summary is not intended to describe each disclosed embodiment or every implementation of the present disclosure. The figures and the detailed description below more particularly exemplify illustrative embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Throughout the specification reference is made to the appended drawings wherein: 
         FIG. 1A  is a system block diagram of an ear-worn electronic hearing device configured for use in, on, or about an ear of a wearer in accordance with any of the embodiments disclosed herein; 
         FIG. 1B  is a system block diagram of two ear-worn electronic hearing devices configured for use in, on, or about left and right ears of a wearer in accordance with any of the embodiments disclosed herein; 
         FIG. 2  shows the anatomical planes of a head of a hearing device wearer for purposes of illustration; 
         FIG. 3A  shows a hearing device oriented in a prescribed (e.g., optimal) angular position for operation when deployed in, on, or about a wearer&#39;s ear; 
         FIG. 3B  shows a hearing device oriented in a suboptimal angular position for operation when deployed in, on, or about a wearer&#39;s ear, the hearing device configured to provide improved performance when operating in the suboptimal angular position according to any of the disclosed embodiments; 
         FIG. 4  illustrates a hearing device oriented in different angular positions relative to a horizontal plane which is orthogonal to a direction of gravity, the hearing device configured to provide improved performance when operating in suboptimal angular positions according to any of the disclosed embodiments; 
         FIG. 5  illustrates various components of a hearing device configured to process multiple microphone signals and multiple telecoil signals in accordance with any of the embodiments disclosed herein; 
         FIG. 6  illustrates a method for improving the performance of a hearing device based on angular position of the device in accordance with any of the embodiments disclosed herein; 
         FIG. 7  illustrates a method for improving the performance of a hearing device based on angular position of the device in accordance with any of the embodiments disclosed herein; 
         FIG. 8  illustrates a method for improving the performance of a hearing device based on angular position of the device in accordance with any of the embodiments disclosed herein; 
         FIG. 9  illustrates a method for improving the performance of a hearing device based on angular position of the device in accordance with any of the embodiments disclosed herein; and 
         FIG. 10  illustrates a method for improving the performance of a hearing device based on angular position of the device in accordance with any of the embodiments disclosed herein. 
     
    
    
     The figures are not necessarily to scale. Like numbers used in the figures refer to like components. However, it will be understood that the use of a number to refer to a component in a given figure is not intended to limit the component in another figure labeled with the same number. 
     DETAILED DESCRIPTION 
     A typical hearing aid includes one or more microphones and can also include a telecoil. A telecoil is a device comprising a tiny coil of wire wound around a core that induces an electric current in the coil when in the presence of a changing magnetic field. A telecoil can serve as an alternate or supplemental input device for a hearing aid. For example, a telecoil can be used as an input source instead of, or in addition to, the microphone(s), allowing the hearing aid to receive a magnetic signal which represents sound. 
     A hearing aid&#39;s microphones and telecoils are, by design, oriented for users with typical posture. As such, users with hunched or stooped posture, referred to as kyphosis, often experience diminished hearing aid performance. For example, directional microphones are intended to allow the user to focus on speech originating from an individual who is facing the user. However, users with kyphosis tend to face downward towards their feet instead of towards their communication partner. 
     Similarly, the orientation of a hearing aid telecoil has a direct relationship with respect to the sensitivity that the telecoil will have to a magnetic field emanating from the horizontal plane. Specifically, if a telecoil is oriented 45 degrees from its optimal position (e.g., due to the user&#39;s hunched or stooped posture), the hearing aid will receive a 3 dB lower input. A 60 degree departure from a telecoil&#39;s optimal position will result in a 6 dB lower input, and a 90 degree departure can result in a zero or near-zero input. 
     These positional effects are exacerbated by telecoil positioning within the hearing aid, since the telecoil is often mounted at an angled inside the hearing aid by 15-45 degrees. In an extreme case, a user could tilt their head 30 degrees, but effectively have their telecoil positioned 75 degrees from the optimal position due to kyphosis. Improper hearing aid fittings (such as those that might be performed via an over-the-counter or door-to-door distribution channel) can result in the hearing aid resting on the ear in a suboptimal orientation. For example, if a receiver wire or tubing of a hearing aid is too short, then the device may be oriented excessively downward. If too long, then the device may be oriented excessively upward. Both of these scenarios can result in diminished performance characteristics, similar those described above. 
     Embodiments of the disclosure are directed to various methods and apparatuses for enhancing or optimizing the performance of a hearing device based on the angular position of the hearing device. The angular position of a hearing device can be monitored using one or more sensors (e.g., accelerometer, gyroscope, magnetometer, inertial measurement unit (IMU), etc.), and compared to the orientation for which the device was designed to performed most optimally. In some embodiments, a measurement of SNR or signal strength of one or more of a microphone(s), a telecoil(s) or other magnetic sensor(s) may be used to determine that the hearing device is in a suboptimal position. 
     In some embodiments, the hearing device may provide guidance to the user which helps the user to position the hearing device in a more optimal position. For example, when the signal strength is below a threshold or a motion sensor of the hearing device (e.g., one or more IMU sensors) detects head tilt beyond a certain level, then the hearing device can be configured to provide instructions to the user to e.g., “tilt your head upward to improve your listening experience.” Various methods of notification are contemplated, including auditory, haptic, and visual notifications. Messages may be delivered through the hearing device or by an operatively connected device, e.g. smartwatch, smartphone, etc. 
     In some embodiments, parameters of a signal processing algorithm can be adapted such that a polar pattern of a multiplicity of microphones (e.g., a microphone array) may be optimized for a given orientation. In some embodiments, frequency shaping may occur. In some embodiments, parameters of a noise reduction or speech enhancement algorithm may be adapted to attempt to recapture the amount of noise reduction/speech enhancement that is provided through an optimal directional microphone/telecoil orientation. 
     It is understood that the embodiments described herein may be used with any ear-worn or ear-level electronic device without departing from the scope of this disclosure. The devices depicted in the figures are intended to demonstrate the subject matter, but not in a limited, exhaustive, or exclusive sense. Ear-worn electronic hearing devices (referred to herein as “hearing devices”) typically include an enclosure, such as a housing or shell, within or on which internal components are disposed. Typical components of a hearing device can include a processor (e.g., a digital signal processor or DSP), memory circuitry, power management circuitry, one or more communication devices (e.g., a radio, a near-field magnetic induction (NFMI) device), one or more antennas, one or more microphones, one or more telecoils, and a receiver/speaker, for example. Hearing devices can incorporate a long-range communication device, such as a Bluetooth® transceiver or other type of radio frequency (RF) transceiver. A communication device (e.g., a radio or NFMI device) of a hearing device can be configured to facilitate communication between a left ear device and a right ear device of the hearing device. Hearing devices can also incorporate a motion sensor or sensors that can be used to switch input between left and right hearing devices (e.g., assuming left and right devices have varying orientation of the motion sensor(s), such as a telecoil) so that optimal audio can be sent to the opposite hearing device. 
     Hearing devices of the present disclosure can incorporate an antenna operatively coupled to a high-frequency transceiver, such as a 2.4 GHz radio. The RF transceiver can conform to an IEEE 802.11 (e.g., WiFi®) or Bluetooth® (e.g., BLE, Bluetooth® 4. 2, 5.0, 5.1 or later) specification, for example. It is understood that hearing devices of the present disclosure can employ other transceivers or radios, such as a 900 MHz radio. Hearing devices of the present disclosure can be configured to receive streaming audio (e.g., digital audio data or files) from an electronic or digital source. Representative electronic/digital sources (e.g., accessory devices) include an assistive listening system, a TV streamer, a TV, a radio, a smartphone, a laptop, a cell phone/entertainment device (CPED), a consumer electronic device, or other electronic device that serves as a source of digital audio data or other types of data files. Hearing devices of the present disclosure can be configured to effect bi-directional communication (e.g., wireless communication) of data with an external source, such as a remote server via the Internet or other communication infrastructure. Hearing devices that include a left ear device and a right ear device can be configured to effect bi-directional communication (e.g., wireless communication) therebetween, so as to implement ear-to-ear communication between the left and right ear devices. 
     The term hearing device of the present disclosure refers to a wide variety of ear-level electronic devices that can aid a person with impaired hearing. The term hearing device also refers to a wide variety of devices that can produce processed sound for persons with normal hearing. Hearing devices of the present disclosure include hearables (e.g., wearable earphones, headphones, earbuds, audio monitors, virtual reality headsets), hearing aids (e.g., hearing instruments), cochlear implants, and bone-conduction devices, for example. Hearing devices include, but are not limited to, behind-the-ear (BTE), in-the-ear (ITE), in-the-canal (ITC), invisible-in-canal (IIC), receiver-in-canal (RIC), receiver-in-the-ear (RITE) or completely-in-the-canal (CIC) type hearing devices or some combination of the above. Throughout this disclosure, reference is made to a “hearing device,” which is understood to refer to a system comprising a single left ear device, a single right ear device, or a combination of a left ear device and a right ear device. 
     Embodiments of the disclosure are defined in the claims. However, below there is provided a non-exhaustive listing of non-limiting examples. Any one or more of the features of these examples may be combined with any one or more features of another example, embodiment, or aspect described herein. 
     Example Ex1. An ear-worn electronic hearing device configured for use in, on, or about an ear of a wearer, the device comprising a processor operatively coupled to memory, a speaker or a receiver operatively coupled to the processor, one or both of a microphone arrangement and a telecoil arrangement operatively coupled to the processor, and a sensor operatively coupled to the processor and configured to sense an angular position of the device relative to a horizontal plane oriented orthogonal to a direction of gravity, the angular position of the device substantially corresponding to an orientation of the wearer&#39;s head relative to the horizontal plane, a longitudinal plane orthogonal to the horizontal plane, and a frontal plane orthogonal to the horizontal plane and the longitudinal plane. The processor is configured to detect a change in the angular position of the device from a first angular position to a second angular position, the first angular position corresponding to a specified angular position that provides for a target or optimal level of device performance and the second angular position resulting in suboptimal device performance, and implement a corrective action that improves performance of the device relative to the suboptimal device performance while operating the device at the second angular position. 
     Example Ex2. The device according to Ex1, wherein the processor is configured to determine the first angular position of the device by determining orientation of the wearer&#39;s head in a direction substantially along the horizontal plane, and determine the second angular position of the device by determining the orientation of the wearer&#39;s head in a direction towards the ground. 
     Example Ex3. The device according to Ex1 or Ex2, wherein the processor is configured to compare one or more performance parameters of the device at the second angular position to corresponding one or more performance parameters of the device associated with the target or optimal level of device performance, and implement the corrective action in response to the comparison crossing a predetermined threshold. 
     Example Ex4. The device according to one or more of Ex1 to Ex3, wherein the processor is configured to implement the corrective action by one or more of changing a directional polar pattern of a microphone array of the microphone arrangement, activating selected microphones of the microphone arrangement as a function of angular position of the device, altering a mathematical weighting of one or more of microphone inputs as a function of angular position of the device, receiving signals from selected telecoils of the telecoil arrangement as a function of angular position of the device, altering a mathematical weighting of signals produced by at least two telecoils as a function of angular position of the device, selectively receiving signals from any of one or more microphones and any of one or more telecoils as a function of angular position of the device, and altering a mathematical weighting of signals produced by any of one or more microphones and any one or more telecoils as a function of angular position of the device; 
     Example Ex5. The device according to Ex1, wherein the device comprises first and second microphones situated on a first plane of the device and a third microphone situated on a second plane of the device transverse to the first plane, the processor is configured to implement the corrective action by summing signals produced by the first, second, and third microphones as a function of angular position of the device, and contribution to the summed signals by the third microphone increases as the angular position of the device changes from the first angular position towards the second angular position. 
     Example Ex6. The device according to Ex1, wherein the device comprises the telecoil arrangement and the microphone arrangement, and the processor is configured to implement the corrective action by operating the device exclusively or predominately in a telecoil mode until the angular position of the device reaches a threshold angular position relative to the horizontal plane, switching from the telecoil mode to an acoustic microphone mode and operating the device exclusively or predominately in the acoustic microphone mode in response to the angular position of the device exceeding the threshold angular position, and switching from the acoustic microphone mode to the telecoil mode and operating the device exclusively or predominately in a telecoil mode in response to the angular position of the device no longer exceeding the threshold angular position. 
     Example Ex7. The device according to one or more of Ex1 to Ex6, wherein the processor is configured to implement the corrective action by one of more of generating an audible alert prompting the wearer to change the angular direction of the device towards the horizontal plane, generating a tactile alert prompting the wearer to change the angular direction of the device towards the horizontal plane, and generating an alert signal indicating a need to change the angular direction of the device towards the horizontal plane and transmitting the alert signal to a portable electronic device attached to or situated in proximity to the wearer. 
     Example Ex8. The device according to one or more of Ex1 to Ex7, wherein the processor is configured to implement the corrective action by one or more of performing frequency shaping on signals produced by one or both of the microphone arrangement and the telecoil arrangement of the device, performing frequency filtering on signals produced by one or both of the microphone arrangement and the telecoil arrangement of the device, adjusting one or more parameters of a noise reduction system of the device, and adjusting one or more parameters of a speech enhancement system of the device. 
     Example Ex9. The device according to one or more of Ex1 to Ex8, wherein the sensor comprises one or more of one or more inertial sensors, one or more magnetic sensors, an altimeter or a barometer implemented by the processor configured to process microphone signals to detect changes in altitude or barometric pressure between microphones of the microphone arrangement, and the processor configured to sense changes in signal strength or signal-to-noise ratio using signals produced by the microphone arrangement, the telecoil arrangement or the sensor of the device. 
     Example Ex10. The device according to one or more of Ex1 to Ex9, wherein the processor is configured to determine the angular position of the device using one or both of a positional sensor and a motion sensor. 
     Example Ex11. A method implemented by an ear-worn electronic device situated in, on, or about an ear of a wearer, the method comprising sensing an angular position of the device relative to a horizontal plane oriented orthogonal to a direction of gravity, the angular position of the device substantially corresponding to an orientation of the wearer&#39;s head relative to the horizontal plane, a longitudinal plane orthogonal to the horizontal plane, and a frontal plane orthogonal to the horizontal plane and the longitudinal plane; detecting a change in the angular position of the device from a first angular position to a second angular position, the first angular position corresponding to a specified angular position that provides for a target or optimal level of device performance and the second angular position resulting in suboptimal device performance; and implementing, by the device, a corrective action that improves performance of the device relative to the suboptimal device performance while operating the device at the second angular position. 
     Example Ex12. The method according to Ex11, wherein the first angular position of the device is determined by the orientation of the wearer&#39;s head in a direction substantially along the horizontal plane, and the second angular position of the device is determined by the orientation of the wearer&#39;s head in a direction towards the ground. 
     Example Ex13. The method according to Ex11 or Ex12, comprising comparing one or more performance parameters of the device at the second angular position to corresponding one or more performance parameters of the device associated with the target or optimal level of device performance, and implementing the corrective action by the device in response to the comparison crossing a predetermined threshold. 
     Example Ex14. The method according to one or more of Ex11 to Ex13, wherein implementing the corrective action comprises one or more of changing a directional polar pattern of a microphone array of the microphone arrangement, activating selected microphones of the microphone arrangement as a function of angular position of the device, altering a mathematical weighting of one or more of microphone inputs as a function of angular position of the device, receiving signals from selected telecoils of the telecoil arrangement as a function of angular position of the device, altering a mathematical weighting of signals produced by at least two telecoils as a function of angular position of the device, selectively receiving signals from any of one or more microphones and any of one or more telecoils as a function of angular position of the device, and altering a mathematical weighting of signals produced by any of one or more microphones and any one or more telecoils as a function of angular position of the device; 
     Example Ex15. The method according to one or more of Ex11 to Ex14, wherein implementing the corrective action comprises one or more of generating an audible alert prompting the wearer to change the angular direction of the device towards the horizontal plane, generating a tactile alert prompting the wearer to change the angular direction of the device towards the horizontal plane, and generating an alert signal indicating a need to change the angular direction of the device towards the horizontal plane and transmitting the alert signal to a portable electronic device attached to or situated in proximity to the wearer. 
       FIG. 1A  is a system block diagram of an ear-worn electronic hearing device configured for use in, on, or about an ear of a wearer in accordance with any of the embodiments disclosed herein. The hearing device  100  shown in  FIG. 1A  can represent a single hearing device configured for monaural or single-ear operation or one of a pair of hearing devices configured for binaural or dual-ear operation (see e.g.,  FIG. 1B ). The hearing device  100  shown in  FIG. 1A  includes a housing  102  within or on which various components are situated or supported. 
     The hearing device  100  includes a processor  104  operatively coupled to memory  106 . The processor  104  can be implemented as one or more of a multi-core processor, a digital signal processor (DSP), a microprocessor, a programmable controller, a general-purpose computer, a special-purpose computer, a hardware controller, a software controller, a combined hardware and software device, such as a programmable logic controller, and a programmable logic device (e.g., FPGA, ASIC). The processor  104  can include or be operatively coupled to memory  106 , such as RAM, SRAM, ROM, or flash memory. In some embodiments, processing can be offloaded or shared between the processor  104  and a processor of a peripheral or accessory device. 
     A microphone arrangement  108  is operatively coupled to the processor  104 . The microphone arrangement  108  can include one or more discrete microphones or a microphone array(s) (e.g., configured for microphone array beamforming). Each of the microphones of the microphone arrangement  108  can be situated at different locations of the housing  102 . It is understood that the term microphone used herein can refer to a single microphone or multiple microphones unless specified otherwise. The microphones of the microphone arrangement  108  can be any microphone type. In some embodiments, the microphones are omnidirectional microphones. In other embodiments, the microphones are directional microphones. In further embodiments, the microphones are a combination of one or more omnidirectional microphones and one or more directional microphones. One, some, or all of the microphones can be microphones having a cardioid, hypercardioid, supercardioid or lobar pattern, for example. One, some, or all of the microphones can be multi-directional microphones, such as bidirectional microphones. One, some, or all of the microphones can have variable directionality, allowing for real-time selection between omnidirectional and directional patterns (e.g., selecting between omni, cardioid, and shotgun patterns). In some embodiments, the polar pattern(s) of one or more microphones of the microphone arrangement  108  can vary depending on the frequency range (e.g., low frequencies remain in an omnidirectional pattern while high frequencies are in a directional pattern). 
     Depending on the hearing device implementation, different microphone technologies can be used. For example, the hearing device  100  can incorporate any of the following microphone technology types (or combination of types): MEMS (micro-electromechanical system) microphones (e.g., capacitive, piezoelectric MEMS microphones), moving coil/dynamic microphones, condenser microphones, electret microphones, ribbon microphones, crystal/ceramic microphones (e.g., piezoelectric microphones), boundary microphones, PZM (pressure zone microphone) microphones, and carbon microphones. 
     A telecoil arrangement  112  is operatively coupled to the processor  104 , and includes one or more (e.g., 1, 2, 3, or 4) telecoils. It is understood that the term telecoil used herein can refer to a single telecoil or magnetic sensor or multiple telecoils or magnetic sensors unless specified otherwise. Also, the term telecoil can refer to an active (powered) telecoil or a passive telecoil (which only transforms received magnetic field energy). The telecoils of the telecoil arrangement  112  can be positioned within the housing  102  at different angular orientations. The hearing device  100  includes a speaker or a receiver  110  capable of transmitting sound from the hearing device  100  to the wearer&#39;s ear drum. A power source  107  provides power for the various components of the hearing device  100 . The power source  107  can include a rechargeable battery (e.g., lithium-ion battery), a conventional battery, and/or a supercapacitor arrangement. 
     The hearing device  100  also includes a motion sensor arrangement  114 . The motion sensor arrangement  114  includes one or more sensors configured to sense motion and/or a position of the wearer of the hearing device  100 . The motion sensor arrangement  114  can comprise one or more of an inertial measurement unit or IMU, an accelerometer(s), a gyroscope(s), a nine-axis sensor, a magnetometer(s) (e.g., a compass), and a GPS sensor. The IMU can be of a type disclosed in commonly owned U.S. Pat. No. 9,848,273, which is incorporated herein by reference. In some embodiments, the motion sensor arrangement  114  can comprise two microphones of the hearing device  100  (e.g., microphones of left and right hearing devices  100 ) and software code executed by the processor  104  to serve as altimeters or barometers. The processor  104  can be configured to compare small changes in altitude/barometric pressure using microphone signals to determine orientation (e.g., angular position) of the hearing device  100 . For example, the processor  104  can be configured to sense the angular position of the hearing device  100  by processing microphone signals to detect changes in altitude or barometric pressure between microphones of the microphone arrangement  108 . 
     The hearing device  100  can incorporate an antenna  118  operatively coupled to a communication device  116 , such as a high-frequency radio (e.g., a 2.4 GHz radio). The radio(s) of the communication device  116  can conform to an IEEE 802.11 (e.g., WiFi®) or Bluetooth® (e.g., BLE, Bluetooth® 4. 2, 5.0, 5.1 or later) specification, for example. It is understood that the hearing device  100  can employ other radios, such as a 900 MHz radio. In addition, or alternatively, the hearing device  100  can include a near-field magnetic induction (NFMI) sensor for effecting short-range communications (e.g., ear-to-ear communications, ear-to-kiosk communications). 
     The antenna  118  can be any type of antenna suitable for use with a particular hearing device  100 . A representative list of antennas  118  include, but are not limited to, patch antennas, planar inverted-F antennas (PIFAs), inverted-F antennas (IFAs), chip antennas, dipoles, monopoles, dipoles with capacitive-hats, monopoles with capacitive-hats, folded dipoles or monopoles, meandered dipoles or monopoles, loop antennas, Yagi-Udi antennas, log-periodic antennas, and spiral antennas. Many of these types of antenna can be implemented in the form of a flexible circuit antenna. In such embodiments, the antenna  118  is directly integrated into a circuit flex, such that the antenna  118  does not need to be soldered to a circuit that includes the communication device  116  and remaining RF components. 
     The hearing device  100  also includes a user interface  120  operatively coupled to the processor  104 . The user interface  120  is configured to receive an input from the wearer of the hearing device  100 . The input from the wearer can be a touch input, a gesture input, or a voice input. The user interface  120  can include one or more of a tactile interface, a gesture interface, and a voice command interface. The tactile interface can include one or more manually actuatable switches (e.g., a push button, a toggle switch, a capacitive switch). For example, the user interface  120  can include a number of manually actuatable buttons or switches, at least one of which can be used by the wearer when customizing the directionality of the microphones  108 . 
     As was discussed previously, embodiments of the disclosure are directed to various methods and apparatuses for optimizing the performance of a hearing device based on the angular position of the hearing device. To facilitate an understanding of various embodiments, reference is made to  FIG. 2  which shows the anatomical planes  200  of a head  202  of a hearing device wearer. An anatomical plane is a hypothetical plane used to transect the wearer&#39;s head in order to describe the movements of the wearer&#39;s head.  FIG. 2  shows a horizontal plane  210 , also referred to as a transverse or axial plane. In the description of various embodiments, the horizontal plane  210  refers to a reference plane which is oriented orthogonal to a direction of gravity.  FIG. 2  also shows a longitudinal plane  214 , also referred to as a median or sagittal plane. The longitudinal plane  214  is orthogonal to the horizontal plane  210  and divides the head into left and right portions.  FIG. 2  further shows a frontal plane  212 , also referred to as the coronal plane. The frontal plane  212 , which is orthogonal to the longitudinal plane  214  and the horizontal plane  210 , divides the head into back and front portions. 
     Movement of the wearer&#39;s head  102  is based on movements of the wearer&#39;s neck. There are six movements of the human neck. A first neck movement is referred to as flexion, which is movement in which the chin is lowered down towards the chest. A second neck movement is referred to as extension, in which the neck is extended, as in looking upward toward the ceiling. The third and fourth neck movements are lateral rotation to the left and lateral rotation to the right (direct lateral rotation to either side). The fifth and sixth neck movements are lateral flexion, which may be described as trying to place the ear upon the shoulder through a sideways movement of the neck, directing that ear toward the shoulder tip on both sides. Embodiments of the disclosure are directed to sensing and correcting for the angular position of a hearing device due largely to flexion and extension motions of the wearer&#39;s neck and, to a lesser degree, lateral flexion and lateral extension of the wearer&#39;s neck. 
     In accordance with any of the embodiments disclosed herein, and with further reference to  FIGS. 1A, 1B, and 2 , an ear-worn electronic hearing device  100  is configured for use in, on, or about an ear of a wearer and comprises a processor  104  operatively coupled to memory  106 . A speaker or a receiver  110  is operatively coupled to the processor  104 . One or both of a microphone arrangement  108  and a telecoil arrangement  112  is operatively coupled to the processor  104 . A motion sensor  114  is operatively coupled to the processor  104  and configured to sense an angular position of the device  100  relative to a horizontal plane  210  oriented orthogonal to a direction of gravity, g. The angular position of the hearing device  100  substantially corresponds to an orientation of the wearer&#39;s head relative to the horizontal plane  210 , a longitudinal plane  212  orthogonal to the horizontal plane  210 , and a frontal plane  212  orthogonal to the horizontal plane  210  and the longitudinal plane  214 . 
     According to disclosed embodiments, the processor  104  is configured to detect a change in the angular position of the hearing device  100  from a first angular position to a second angular position. The first angular position corresponds to a specified angular position that provides for a prescribed or optimal level (e.g., designed or target level) of hearing device performance, and the second angular position results in suboptimal hearing device performance. The first angular position can be based on how the hearing device  100  is designed and/or calibrated by the manufacturer or how the hearing device  100  has been configured by e.g., an audiologist who has adjusted the hearing device settings for the wearer. For example, through real-ear verification measures, the audiologist may have set the hearing device  100  to provide optimal telecoil audibility for the wearer in their office hearing loop, which in effect corrects for the natural hunch of the user. In this illustrative scenario, if the wearer moves to a “more optimal position” as designed by the manufacturer, the settings could result in audio output that is too loud. 
     The processor  104  is configured to implement a corrective action that improves performance of the hearing device  100  relative to the suboptimal device performance while operating the hearing device  100  at the second angular position. In some embodiments, one of the processors  104  of a binaural hearing device system (e.g., left or right device processor  104   a ,  104   b ) is configured to implement the processes described above and elsewhere herein. In other embodiments, and as shown in  FIG. 1B , the processor  104   a  of a left hearing device  100   a  and the processor  104   b  of a right hearing device  100   b  are configured to cooperate via a communication link  105  (e.g., an RF or NFMI link) to implement the processes described above and elsewhere herein. In further embodiments, one or more of the processors  104   a ,  104   b  and a processor or processors  104   c  of one or more peripheral and/or accessory devices  101  are configured to cooperate via a communication links  105 ,  103  (e.g., RF and/or NFMI links) to implement the processes described above and elsewhere herein. In some embodiments, the left and right hearing devices  100   a ,  100   b  can be configured to communicate through an “Ear-Phone-Ear” pattern by leveraging the peripheral device  104   c  via communication link(s)  103 . 
       FIG. 3A  shows a hearing device  300   a  oriented in a prescribed (e.g., optimal) angular position for operation when deployed in, on, or about a wearer&#39;s ear. The hearing device  300   a  includes a pair of microphones  302 ,  304 , which may be omnidirectional microphones whose signals may be processed to form a variety of sensitivity patterns. As is shown in  FIG. 3A , the prescribed angular position of the hearing device  300   a  provides for a forward focus of the sensitivity pattern provided by microphones  302 ,  304 .  FIG. 3B  shows a hearing device  300   b  in a suboptimal angular position due to flexion of the wearer&#39;s neck or hunched or stooped posture of the wearer. As can be seen in  FIG. 3B , the suboptimal angular position of the hearing device  300   b  provides for a downward focus of the sensitivity pattern provided by microphones  302 ,  304 . 
     According to any of the disclosed embodiments, the hearing device  300   b  can include one or more additional microphones  306  positioned at a location of the hearing device housing which is out-of-plane with respect to a plane of microphones  302 ,  304 . For example, microphones  302 ,  304  can be omnidirectional microphones placed on the top of the hearing device  300   b  (e.g., on the top of a standard BTE-type hearing device). The addition of microphone  306  (e.g., on the back or bottom of a standard BTE-type hearing device) can allow the hearing device  300   b  to form a polar pattern similar to that provided by device  300   a , but at an optimal angle for an individual who is hunching or stooped over. For example, the microphones  302  and  304  are too close to each other along the horizontal plane when in the hearing device  300   b  is the angular position show in  FIG. 3B . Utilizing the additional microphone  306  situated at a location of the hearing device  300   b  out-of-plane relative to the plane of microphones  302 ,  304  provides for enhanced or optimal device performance when operating at the suboptimal angular position shown in  FIG. 3B . 
     According to any of the disclosed embodiments, the hearing device  300   b  can also include one or more telecoils, such as telecoil  310  and  312  shown in  FIG. 3B . It is noted that telecoil  310  is oriented within the hearing device  300   b  to provide prescribed (e.g., optimal) performance when the hearing device  300   b  is oriented in a prescribed (e.g., optimal) angular position for operation, such as that shown in  FIG. 3A . The telecoil  312  is situated within the housing of hearing device  300   b  so that it is oriented at a more preferred angular position relative to telecoil  310  when the wearer&#39;s posture is hunched or stooped or when the wearer&#39;s neck is in flexion, as is depicted in  FIG. 3B . 
     In some embodiments, one or more additional telecoils and/or one or more additional microphones can be added as a “module” or “wart” to a standard hearing device (e.g., as an aftermarket option). For example, one or more additional telecoils and/or microphones can be added to a hearing device or devices much like current approaches to attaching a DAI (direct audio input) or programming “boots” to hearing aids. 
     A hearing device according to any of the embodiments disclosed herein can be configured to switch between a telecoil mode and an acoustic microphone mode depending on the angular position of the hearing device relative to a horizontal plane which is oriented orthogonal to a direction of gravity. For example, the hearing device can be configured to switch from a telecoil mode to an acoustic microphone mode when the hearing device orientation crosses a threshold, such as when the wearer is looking downward. In this illustrative embodiment, the threshold angle can be set such that if the angle of the telecoil in the hearing device relative to the horizontal plane falls below a threshold angle, performance is reduced by an unacceptable degree. To continue to provide sufficient hearing assistance, the hearing device can be configured automatically switch to an acoustic microphone mode, until the angle of the hearing device relative to the horizontal plane is exceeded. In this illustrative example, it is assumed that the threshold angle represents the most extreme acute angle that can be measured in three-dimensional space between the telecoil and the horizontal plane (e.g., ground). In some embodiments, a method of normalizing the audio levels between acoustic and telecoil inputs that are switching adaptively can be implemented by the hearing device, such as in manners disclosed in commonly owned U.S. Patent Application Ser. No. 62/914,771, filed on Oct. 14, 2019 under Attorney Docket No. 899.715PRV, and entitled “HEARING ASSISTANCE SYSTEM WITH AUTOMATIC HEARING LOOP MEMORY,” which is incorporated herein by reference. 
       FIG. 4  illustrates hearing device  402  oriented in different angular positions relative to a horizontal plane  404  which is orthogonal to a direction of gravity. In scenario A, the hearing device  402  is oriented in a prescribed (e.g., optimal) angular position for operation relative to the horizontal plane  404 . In scenarios B and C, the hearing device  402  is oriented in progressively suboptimal angular positions for operation relative to the horizontal plane  404 . For purposes of illustration, and not of limitation, the hearing device  402  includes a microphone arrangement  410  comprising three microphones, M 1 , M 2 , M 3 . The hearing device  402  also includes a telecoil arrangement  412  comprising three telecoils, T 1 , T 2 , T 3 . It is understood that the number of microphones and telecoils can be the same or different, ranging between 1 and 5, for example. The hearing device  402  includes an IMU  420  configured to measure the angular position of the hearing device  402 . The IMU  420  can be representative of any one or combination of position and/or motion sensors, such as any combination of one or more accelerometers, gyroscopes, and magnetometers. A processor  430  of the hearing device  402  and/or a processor of a peripheral or accessory device is operatively coupled to the IMU  420 , the microphone arrangement  410 , and the telecoil arrangement  412 . 
     Microphones M 1  and M 2  are situated on the hearing device  402  to provide a sensitivity pattern which is forward focused (e.g., substantially parallel to the horizontal plane  404 ) when the wearer&#39;s head is positioned at an optimal position, such as that shown in  FIG. 2 . Microphone M 3  is positioned out-of-plane relative to a plane of microphones M 1  and M 2 . Telecoils T 1 , T 2 , T 3  have longitudinal axes  413  oriented at different angles relative to a plane parallel to a direction of gravity. For example, the longitudinal axes  413  can be oriented at different angles ranging between 0 and 90° relative to the plane parallel to the direction of gravity. 
     In scenario A, the angular position of the hearing device  402  is substantially parallel to the horizontal plane  404 , in which case an angle, β 0 , measured by IMU  420  is substantially zero degrees. In this scenario, the processor  430  is configured to select microphones M 1  and M 2  and telecoil T 1  for operation, in which case signals produced by microphones M 1  and M 2  and telecoil T 1  are received and processed by the processor  430 . In scenario B, the angular position of the hearing device  402  is suboptimal due to flexion of the wearer&#39;s neck or hunched/stooped posture of the wearer resulting in a relatively large angle, β 1 , as measured by the IMU  420 . In this scenario, the processor  430  is configured to implement a corrective action by changing the directional polar pattern of the microphone arrangement  410  and selecting telecoil T 2  for operation. In this scenario, signals produced by microphones M 2  and M 3  and telecoil T 2  are received and processed by the processor  430 . In scenario C, the angular position of the hearing device  402  is more suboptimal than in scenario B due to more excessive flexion of the wearer&#39;s neck or hunched/stooped posture of the wearer resulting in a relatively large angle, β 2 , as measured by the IMU  420 . In this scenario, the processor  430  is configured to implement a corrective action by selecting microphones M 2  and M 3 , and telecoil T 3 , for operation, in which case signals produced by microphones M 2  and M 3  and telecoil T 3  are received and processed by the processor  430 . 
       FIG. 5  illustrates various components of a hearing device  500  configured to process multiple microphone signals and multiple telecoil signals in accordance with any of the embodiments disclosed herein. The hearing device  500  shown in  FIG. 5  includes a microphone arrangement  510  comprising three microphones M 1 , M 2 , M 3 . The hearing device  500  also includes a telecoil arrangement  512  comprising three telecoils T 1 , T 2 , T 3 . It is understood that the number of microphones and telecoils can be the same or different, ranging between 1 and 5, for example. The hearing device  500  further includes a processor  530  operatively coupled to an IMU  520 , the microphone arrangement  510  and the telecoil arrangement  512 . The IMU  520  can be representative of any one or combination of position and/or motion sensors, such as any combination of one or more accelerometers, gyroscopes, and magnetometers. The processor  530  includes a weighting module  540 , a first summing device  542 , and a second summing device  544 . 
     The processor  530  is configured to implement a corrective action that improves performance of the hearing device  500  in response to detecting a suboptimal angular position of the hearing device  500  (via the IMU  520 ) relative to the horizontal plane oriented orthogonal to a direction of gravity. As was discussed previously, the processor  530  can be configured to implement a corrective action by activating selected microphones M 1 , M 2 , M 3  as a function of angular position of the hearing device  500  as measured by the IMU  520 . The processor  530  can also be configured to implement the corrective action by receiving signals from selected telecoils T 1 , T 2 , T 3  as a function of angular position of the hearing device  500  as measured by the IMU  520 . 
     The processor  530  can be configured to alter a mathematical weighting (e.g., via weights w 1 , w 2 , w 3 , . . . w n ) of one or more of the microphone inputs to the first summing device  542  as a function of angular position of the hearing device  500  as measured by the IMU  520 . Additionally or alternatively, the processor  530  can be configured to alter a mathematical weighting (via weights w 4 , w 5 , w 6 , . . . w n ) of one or more of the telecoil inputs to the second summing device  544  as a function of angular position of the hearing device  500  as measured by the IMU  520 . For example, a weighted contribution to the summed microphone signal  543  by out-of-plane microphone M 3  can increase proportionally as a function of the angular position of the hearing device  500  as the device  500  changes from an angular position substantially parallel to the horizontal plane to an angular position directed towards the ground. Similarly, a weighted contribution to the summed telecoil signal  545  by telecoil T 3  can increase proportionally as a function of the angular position of the hearing device  500  as the device  500  changes from an angular position substantially parallel to the horizontal plane to an angular position directed towards the ground. Microphone and telecoil signals  543 ,  545  output from the first and second summing devices  542 ,  544  can be further processed by the processor  530  and/or other circuitry of the hearing device  500  (e.g., audio signal processing circuitry, telecoil processing circuitry) to provide enhanced or optimized hearing device performance. 
       FIGS. 6-10  illustrate various methods for improving the performance of a hearing device based on angular position of the hearing device in accordance with any of the embodiments disclosed herein. For example, the methods shown in  FIGS. 6-10  can be implemented by any of the hearing devices illustrated in  FIGS. 1A, 1B, and 3-5 . 
       FIG. 6  illustrates a method for improving the performance of a hearing device based on angular position of the device in accordance with any of the embodiments disclosed herein. The method shown in  FIG. 6  involves sensing  602  an angular position of the hearing device relative to a horizontal plane oriented orthogonal to a direction of gravity. The method involves detecting  604  change in the angular position of the hearing device from a first angular position to a second angular position. The first angular position corresponds to a specified angular position (e.g., a predefined or designed angular position in, on, or about the wearer&#39;s ear) that provides for a target or optimal level of device performance. The second angular position results in suboptimal hearing device performance. The second angular position can result, for example, from flexion, extension, lateral flexion, and/or lateral extension of the wearer&#39;s neck during operation of the hearing device. The method also involves implementing  606 , by the hearing device, a corrective action that improves performance of the hearing device relative to the suboptimal device performance while operating the device at the second angular position. 
     The method shown in  FIG. 6  and other figures can involve comparing one or more performance parameters of the hearing device at the second angular position to corresponding one or more performance parameters of the hearing device associated with the target/optimal level of device performance. For example, the method may involve measuring the SNR or signal strength of one or more microphones, telecoils or other magnetic sensors of the hearing device to determine that the hearing device is in a suboptimal position. The method may involve implementing the corrective action by the hearing device in response to the comparison crossing a predetermined threshold (e.g., a predetermined difference in SNR or signal strength measurements). 
       FIG. 7  illustrates a method for improving the performance of a hearing device based on angular position of the device in accordance with any of the embodiments disclosed herein. The method shown in  FIG. 7  involves implementing  702  one or more corrective actions by the processor of the hearing device and/or a processor of a peripheral or accessory device that improves hearing device performance. The one or more corrective actions implemented by the hearing device processor and/or a processor of a peripheral or accessory device can be performed sequentially or concurrently. For example, some corrective actions can be implemented simultaneously, while other corrective actions can be implemented sequentially by the hearing device processor and/or a processor of a peripheral or accessory device. 
     A corrective action implemented by the hearing device processor and/or a processor of a peripheral or accessory device can include changing  704  a directional polar pattern of two or more microphones of the hearing device. A corrective action can involve activating  706  selected microphones as a function of angular position of the hearing device. A corrective action can further involve altering  708  a mathematical weighting of one or more of the microphone inputs as a function of angular position of the hearing device. A corrective action can involve receiving  710  signals from selected ones of the telecoils as a function of angular position of the hearing device. A corrective action can include altering  712  a mathematical weighting of signals produced by at least two telecoils as a function of angular position of the hearing device. 
     A corrective action implemented by the hearing device processor and/or a processor of a peripheral or accessory device can involve selectively receiving  714  signals from any one or more microphones and any one or more telecoils as a function of angular position of the hearing device. A corrective action can involve altering  716  a mathematical weighting of signals produced by any one or more microphones and any one or more telecoils as a function of angular position of the hearing device. A corrective action can also involve summing  718  signals produced by two or more microphones as a function of angular position of the hearing device. A corrective action can further involve summing  720  signals produced by two or more telecoils as a function of angular position of the hearing device. A corrective action implemented by the hearing device processor and/or a processor of a peripheral or accessory device can involve summing of microphone signals and summing of telecoil signals as a function of angular position of the hearing device as described in blocks  718  and  720 . 
       FIG. 8  illustrates a method for improving the performance of a hearing device based on angular position of the device in accordance with any of the embodiments disclosed herein. The method shown in  FIG. 8  involves implementing  802  one or more corrective actions by the processor of the hearing device and/or a processor of a peripheral or accessory device that improves for device performance. The one or more corrective actions implemented by the hearing device processor and/or a processor of a peripheral or accessory device can be performed sequentially or concurrently. For example, some corrective actions can be implemented simultaneously, while other corrective actions can be implemented sequentially by the hearing device processor and/or a processor of a peripheral or accessory device. A corrective action implemented by the hearing device processor and/or a processor of a peripheral or accessory device can include generating  804  an audible alert prompting the wearer to change the angular direction of the device towards a horizontal plane which is orthogonal to a direction of gravity. The one or more corrective actions can include generating  806  a tactile alert prompting the wearer to change the angular direction of the device towards the horizontal plane. A corrective action can involve transmitting  808  an alert signal indicating a need to change angular direction of the hearing device towards the horizontal plane to a portable electronic device attached to or situated in proximity to the wearer. 
     A corrective action implemented by the hearing device processor and/or a processor of a peripheral or accessory device can include performing  810  frequency shaping on signals produced by one or both of a microphone arrangement and a telecoil arrangement. A corrective action can include performing  812  frequency filtering on signals produced by one or both of the microphone arrangement and the telecoil arrangement of the hearing device. A corrective action can involve adjusting  814  one or more parameters of a noise reduction system of the hearing device. For example, the hearing device processor can be configured to adjust one or more parameters of a noise reduction system that implements Fast Signal Mic Noise Reduction (FSMNR), spectral subtraction, spectral subtraction with over subtraction model, non-linear spectral subtraction, adaptive noise cancellation, Winer filtering, Kalman filtering, and beamforming noise suppression, for example. A corrective action implemented by the hearing device processor can include adjusting  816  one or more parameters of a speech enhancement system of the hearing device. For example, the hearing device processor and/or a processor of a peripheral or accessory device can be configured to adjust one or more parameters of a speech enhancement system that implements a frequency lowering/shifting technique, phoneme augmentation, linear predictive coding, and signal subspace methods, for example. 
       FIG. 9  illustrates a method for improving the performance of a hearing device based on angular position of the device in accordance with any of the embodiments disclosed herein. The method shown in  FIG. 9  involves operating  902  the hearing device exclusively or predominately in a telecoil mode until the angular position of the hearing device crosses a first angular position threshold relative to a horizontal plane which is orthogonal to a direction of gravity. The method involves switching  904  from the telecoil mode to an acoustic microphone mode and operating the device exclusively or predominately in the acoustic microphone mode in response to the angular position of the hearing device crossing the first angular position threshold. The method also involves switching  906  from the acoustic microphone mode to the telecoil mode and operating the device exclusively or predominately in a telecoil mode in response to the angular position of the device crossing a second angular position threshold. During each of the three operating phases  902 ,  904 ,  906 , performance of the hearing device may involve a mix of signals from the telecoil and microphone arrangements, hence the use of the term “predominately operating” in the telecoil mode (which can involve use of microphone signals) and “predominately operating” in the acoustic microphone mode (which can involve use of telecoil signals). 
       FIG. 10  illustrates a method for improving the performance of a hearing device based on angular position of the device in accordance with any of the embodiments disclosed herein. The method shown in  FIG. 10  involves summing  1002  signals produced by a telecoil arrangement and a microphone arrangement the hearing device. The method involves operating  1004  the hearing device in a telecoil mode until the angular position of the device crosses a first angular position threshold relative to a horizontal plane which is orthogonal to a direction of gravity. The method also involves switching  1006  from the telecoil mode to an acoustic microphone mode in response to the angular position of the device crossing the first angular position threshold. The method further involve switching  1008  from the acoustic microphone mode to the telecoil mode in response to the angular position of the hearing device crossing a second angular position threshold. 
     The method also involves weighting signals from the telecoil arrangement and the microphone arrangement based on the angular position of the hearing device. According to the method shown in  FIG. 10 , a weighted contribution to the summed signals  1010  is substantially from telecoil arrangement signals when operating in the telecoil mode. Also according to the method shown in  FIG. 10 , a weighted contribution to the summed signals  1012  is substantially from microphone arrangement signals when operating in the acoustic microphone mode. The method shown in  FIG. 10  can be implemented by a processor of the hearing device and/or a processor of a peripheral or accessory device. 
     Although reference is made herein to the accompanying set of drawings that form part of this disclosure, one of at least ordinary skill in the art will appreciate that various adaptations and modifications of the embodiments described herein are within, or do not depart from, the scope of this disclosure. For example, aspects of the embodiments described herein may be combined in a variety of ways with each other. Therefore, it is to be understood that, within the scope of the appended claims, the claimed invention may be practiced other than as explicitly described herein. 
     All references and publications cited herein are expressly incorporated herein by reference in their entirety into this disclosure, except to the extent they may directly contradict this disclosure. Unless otherwise indicated, all numbers expressing feature sizes, amounts, and physical properties used in the specification and claims may be understood as being modified either by the term “exactly” or “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the foregoing specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by those skilled in the art utilizing the teachings disclosed herein or, for example, within typical ranges of experimental error. 
     The recitation of numerical ranges by endpoints includes all numbers subsumed within that range (e.g.  1  to  5  includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5) and any range within that range. Herein, the terms “up to” or “no greater than” a number (e.g., up to 50) includes the number (e.g., 50), and the term “no less than” a number (e.g., no less than 5) includes the number (e.g., 5). 
     The terms “operatively coupled” or “connected” refer to elements being attached to each other either directly (in direct contact with each other) or indirectly (having one or more elements between and attaching the two elements). Either term may be modified by “operatively” and “operably,” which may be used interchangeably, to describe that the coupling or connection is configured to allow the components to interact to carry out at least some functionality (for example, a radio chip may be operably operatively coupled to an antenna element to provide a radio frequency electromagnetic signal for wireless communication). 
     Terms related to orientation, such as “top,” “bottom,” “side,” and “end,” are used to describe relative positions of components and are not meant to limit the orientation of the embodiments contemplated. For example, an embodiment described as having a “top” and “bottom” also encompasses embodiments thereof rotated in various directions unless the content clearly dictates otherwise. 
     Reference to “one embodiment,” “an embodiment,” “certain embodiments,” or “some embodiments,” etc., means that a particular feature, configuration, composition, or characteristic described in connection with the embodiment is included in at least one embodiment of the disclosure. Thus, the appearances of such phrases in various places throughout are not necessarily referring to the same embodiment of the disclosure. Furthermore, the particular features, configurations, compositions, or characteristics may be combined in any suitable manner in one or more embodiments. 
     The words “preferred” and “preferably” refer to embodiments of the disclosure that may afford certain benefits, under certain circumstances. However, other embodiments may also be preferred, under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful and is not intended to exclude other embodiments from the scope of the disclosure. 
     As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” encompass embodiments having plural referents, unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term “or” is generally employed in its sense including “and/or” unless the content clearly dictates otherwise. 
     As used herein, “have,” “having,” “include,” “including,” “comprise,” “comprising” or the like are used in their open-ended sense, and generally mean “including, but not limited to.” It will be understood that “consisting essentially of” “consisting of,” and the like are subsumed in “comprising,” and the like. The term “and/or” means one or all of the listed elements or a combination of at least two of the listed elements. 
     The phrases “at least one of,” “comprises at least one of,” and “one or more of” followed by a list refers to any one of the items in the list and any combination of two or more items in the list.