Device and method for adjusting pressure sensor data

Abstract

The invention relates to a device and a method for adjusting pressure sensor data. In accordance with various embodiments of the present disclosure, an apparatus is provided that includes a pressure sensor, an accelerometer, and a controller. The controller is configured to determine a tilt angle of the device, receive an unadjusted pressure value from the pressure sensor, determine a pressure adjustment value based on (a) the tilt angle and (b) slope values of pressure test data taken at a first test angle and at a second test angle different from the first test angle, and determining an adjusted pressure value by adding the determined pressure adjustment value to the received unadjusted pressure value.

Description

Technical Field

[0001] The exemplary embodiments of this disclosure generally relate to pressure sensors, and more specifically, to waterproof pressure sensors. Background Technology

[0002] Pressure sensors are commonly used in mobile and wearable devices, such as mobile phones and smartwatches. Such pressure sensors are used to determine air pressure, which can be used to determine the height of the device (and therefore the user). This air pressure determination can also be used to detect when a user has fallen by detecting very small pressure changes (e.g., about 0.1 hPa) corresponding to very small changes in height (e.g., about 80 cm).

[0003] Such pressure sensors are also used to measure water pressure. The measured water pressure can be used to determine underwater depth, which is useful for divers or swimmers. For this reason, mobile and wearable devices are often waterproof, which in turn requires the use of waterproof pressure sensors. Such waterproof pressure sensors typically use a gel inside the sensor to protect the electronics from water exposure.

[0004] However, movement also occurs within the gel when the device is flipped or tilted, which can affect the membrane of the pressure sensor and cause a drift in its pressure sensing capability. This drift in pressure data can cause malfunctions in some algorithms that use pressure data, such as fall detection algorithms.

[0005] The applicant has identified numerous technical challenges and difficulties associated with the use of waterproof sensors in mobile and wearable devices. Through applied effort, ingenuity, and innovation, the applicant has addressed the problems associated with the use of such waterproof sensors by developing the solutions implemented in this disclosure, which are described in detail below. Summary of the Invention

[0006] The various embodiments described herein relate to apparatus and methods for adjusting sensor data from waterproof sensors.

[0007] According to various embodiments of this disclosure, an apparatus including a pressure sensor, an accelerometer, and a controller is provided. The controller is configured to determine a tilt angle of the apparatus, receive an unadjusted pressure value from the pressure sensor, determine a pressure adjustment value based on (a) the tilt angle and (b) slope values ​​of pressure test data taken at a first test angle and a second test angle different from the first test angle, and determine an adjusted pressure value by adding the determined pressure adjustment value to the received unadjusted pressure value.

[0008] In some embodiments, the controller uses data received from the accelerometer to determine the tilt angle of the device.

[0009] In some embodiments, the slope value is based on the average of a plurality of pressure test readings taken at a first test angle and the average of a plurality of pressure test readings taken at a second test angle.

[0010] In some embodiments, the slope value is calculated as (the average of a plurality of pressure test readings taken at the second test angle minus the average of a plurality of pressure test readings taken at the first test angle) divided by the degree difference between the second test angle and the first test angle.

[0011] In some embodiments, the controller is further configured to repeatedly determine the tilt angle of the device, receive an unadjusted pressure value from a pressure sensor, determine a pressure adjustment value based on (a) the tilt angle and (b) the slope value of pressure test data taken at a first test angle and a second test angle, and determine an adjusted pressure value by adding the determined pressure adjustment value to the received unadjusted pressure value.

[0012] In some embodiments, the controller is also configured to determine whether the user of the device has fallen based on repeatedly determined changes in the adjusted pressure value.

[0013] In some embodiments, if repeated determinations of changes in the adjusted pressure value exceed a predetermined threshold, the controller determines that the user of the device has fallen.

[0014] In some embodiments, the device includes a wearable device.

[0015] In some embodiments, the first test angle and the second test angle are 180 degrees apart.

[0016] In some embodiments, the first test angle is zero degrees and the second test angle is 180 degrees.

[0017] According to various embodiments of the present disclosure, a method for adjusting pressure readings from a pressure sensor in a device is provided. In some embodiments, the method includes determining a tilt angle of the device including the pressure sensor; receiving an unadjusted pressure value from the pressure sensor; determining a pressure adjustment value based on (a) the tilt angle and (b) slope values ​​of pressure test data taken at a first test angle and a second test angle different from the first test angle; and determining an adjusted pressure value by adding the determined pressure adjustment value to the received unadjusted pressure value.

[0018] The above summary is provided merely to summarize some exemplary embodiments to provide a basic understanding of some aspects of this disclosure. Therefore, it should be understood that the above embodiments are merely illustrative and should not be construed as narrowing the scope or spirit of this disclosure in any way. It should also be understood that, in addition to the embodiments summarized herein, the scope of this disclosure covers many possible embodiments, some of which will be further described below. Attached Figure Description

[0019] The description of exemplary embodiments can be read in conjunction with the accompanying drawings. It should be understood that, for the sake of simplicity and clarity, the elements illustrated in the figures are not necessarily drawn to scale unless otherwise described. For example, the dimensions of some elements may be exaggerated relative to others unless otherwise described. Embodiments containing the teachings of this disclosure are illustrated and described herein, with reference to the figures, wherein:

[0020] Figure 1 Block diagrams of example devices for adjusting sensor data from a waterproof sensor according to some embodiments of the present disclosure are provided; and

[0021] Figure 2 Example flowcharts illustrating example methods for adjusting sensor data from a waterproof sensor according to some embodiments of the present disclosure are provided. Detailed Implementation

[0022] Some embodiments of this disclosure will now be described more fully below with reference to the accompanying drawings, which illustrate some, but not all, of the embodiments of this disclosure. In fact, these disclosures may be implemented in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Similar reference numerals always refer to similar elements.

[0023] As used herein, terms (such as “front,” “rear,” “top,” etc.) are used for illustrative purposes in the examples provided below to describe the relative positions of certain parts or portions of parts. Furthermore, as will be apparent to those skilled in the art from this disclosure, the terms “substantially” and “generally” indicate that the referenced element or associated description is accurate within applicable engineering tolerances.

[0024] As used herein, the term "comprising" means including but not limited to and should be interpreted in the manner commonly used in the patent context. The use of broader terms (such as comprising, including, and having) should be understood to be supported by narrower terms (such as consisting of, substantially consisting of, and substantially including).

[0025] The phrases “in one embodiment”, “according to one embodiment”, etc., generally mean that the specific feature, structure or characteristic following the phrase can be included in at least one embodiment of this disclosure, and can be included in more than one embodiment of this disclosure (importantly, such phrases do not necessarily refer to the same embodiment).

[0026] The term “example” or “exemplary” is used in this document to mean “serving as an example, instance, or illustration.” Any implementation described as “exemplary” in this document is not necessarily to be construed as being preferred or superior to other implementations.

[0027] If the specification states that a component or feature "may," "can," "will," "should," "will," "preferably," "possibly," "typically," "optionally," "for example," "often," or "maybe" (or other such language) include or have a characteristic, then the specific component or feature is not required to include or have that characteristic. Such a component or feature may be optionally included in some embodiments, or it may be excluded.

[0028] Various embodiments of this disclosure overcome the technical challenges and difficulties described above, and provide various technical improvements and advantages based on example devices, such as, but not limited to, devices that provide adjustment of pressure readings from a waterproof pressure sensor to compensate for drift in pressure sensing capability caused by device tilt. In some embodiments, such devices include mobile devices (e.g., mobile phones), wearable devices (e.g., smartwatches), or any other suitable devices.

[0029] In various embodiments, a pressure adjustment value is used to adjust the pressure reading from the waterproof pressure sensor. In various embodiments, such a pressure adjustment value is calculated using a slope determined during testing using average pressure readings at a zero-degree tilt angle and average pressure readings at a 180-degree tilt angle.

[0030] In various embodiments, a waterproof sensor (such as a gel sensor for an electronic device with a protective sensor) is tested to obtain pressure readings at two different tilt angles. In various embodiments, these two different tilt angles are zero degrees (i.e., upright) and 180 degrees (i.e., inverted). In some embodiments, tilt angles other than zero and 180 degrees may be used. In various embodiments, the pressure sensor test is performed before and / or after the pressure sensor is assembled into the device.

[0031] Figure 1 The illustration shows an exemplary block diagram of an example device specifically configured according to exemplary embodiments of the present disclosure. Specifically, Figure 1 An example wearable device 100 is depicted with a specific configuration according to at least some example embodiments of the present disclosure. Figure 1 The device 100 includes a processing circuitry 102, a memory circuitry 104, an input / output circuitry 106, a communication circuitry 108, a pressure sensor 110 (such as a waterproof pressure sensor), and an accelerometer 112. In the illustrated embodiment, the processing circuitry includes a pressure adjustment circuitry 114 and a fall detection circuitry 116. In some embodiments, the device 100 is configured to perform and execute the operations described herein. For example, the device 100 may be configured to implement the following regarding... Figure 2 The method described is for adjusting sensor data from a waterproof sensor based on the tilt angle of the device.

[0032] Although the components are described with respect to functional limitations, it should be understood that a particular implementation must include the use of specific computing hardware. It should also be understood that in some embodiments, certain components described herein include similar or common hardware. For example, in some embodiments, two sets of circuitry utilize the same processor, memory, circuitry, etc., to perform their associated functions, such that each set of circuitry does not require duplicate hardware.

[0033] Processing circuitry 102 can be implemented in a variety of different ways. In various embodiments, the terms "processor," "processing circuitry," "controller," or "controlling circuitry" should be understood to include a single-core processor, a multi-core processor, multiple processors within device 100, and / or one or more remote or "cloud" processors external to device 100. In some example embodiments, processing circuitry 102 may include one or more processing devices configured to perform independently. Alternatively or additionally, processing circuitry 102 may include one or more processors configured via a bus cascade to enable independent execution of operations, instructions, pipelines, and / or multithreading.

[0034] In an example embodiment, processing circuitry 102 may be configured to execute instructions stored in memory circuitry 104 or otherwise accessible to a processor. Alternatively or additionally, processing circuitry 102 may be configured to perform hard-coded functions. Thus, whether configured by a hardware or software approach, or by a combination thereof, processing circuitry 102 may represent an entity (e.g., physically implemented in a circuitry) capable of performing operations according to embodiments of this disclosure while being appropriately configured. Alternatively or additionally, processing circuitry 102 may be implemented as an executor of software instructions, and these instructions may specifically configure processing circuitry 102 to perform various algorithms implemented in one or more operations described herein when executing such instructions. In some embodiments, processing circuitry 102 includes hardware, software, firmware, and / or combinations thereof for performing one or more operations described herein.

[0035] In some embodiments, the processing circuitry 102 (and / or coprocessor or any other auxiliary processor or processing circuitry 104 otherwise associated with the processor) communicates with the memory circuitry 104 via a bus for transferring information between components of the device 100.

[0036] The memory or memory circuitry 104 may be non-transitory and may include, for example, one or more volatile and / or non-volatile memories. In some embodiments, the memory circuitry 104 includes or implements an electronic storage device (e.g., a computer-readable storage medium). In some embodiments, the memory circuitry 104 is configured to store information, data, content, applications, instructions, etc., to enable the device 100 to perform various operations and / or functions according to exemplary embodiments of this disclosure.

[0037] Input / output circuitry 106 may be included in device 100. In some embodiments, input / output circuitry 106 may provide output to a user and / or receive input from a user. Input / output circuitry 106 may communicate with processing circuitry 102 to provide such functionality. Input / output circuitry 106 may include one or more user interfaces. In some embodiments, the user interface may include a display that includes interfaces presented as a network user interface, application user interface, user device, backend system, etc. In some embodiments, input / output circuitry 106 may also include a keyboard, mouse, joystick, touchscreen, touch area, softkeys, microphone, speaker, or other input / output mechanism. Processing circuitry 102 and / or input / output circuitry 106 may be configured to control one or more operations and / or functions of one or more user interface elements via computer program instructions (e.g., software and / or firmware) stored in memory accessible to a processor (e.g., memory circuitry 104, etc.). In some embodiments, input / output circuitry 106 includes or utilizes user-facing applications to provide input / output functionality to computing devices and / or other displays associated with the user.

[0038] Communication circuitry 108 may be included in device 100. Communication circuitry 108 may include any means, such as devices or circuitry implemented in hardware or a combination of hardware and software that receive data from and / or send data to a network and / or any other device, circuitry, or module communicating with device 100. In some embodiments, communication circuitry 108 includes, for example, a network interface for enabling communication with a wired or wireless communication network. Additionally or alternatively, communication circuitry 108 may include one or more network interface cards, antennas, buses, switches, routers, modems, or any other devices adapted to enable communication via one or more communication networks, supporting hardware, firmware, and / or software. In some embodiments, communication circuitry 108 may include circuitry for interacting with an antenna and / or other hardware or software to induce signal transmission via the antenna and / or process reception of signals received via the antenna. In some embodiments, communication circuitry 108 enables the transmission of data to and / or the reception of data from a user equipment, one or more sensors, and / or other external computing devices communicating with device 100.

[0039] In some embodiments, two or more groups of circuit devices 102 to 108 are composable. Alternatively or additionally, one or more groups of circuit devices 102 to 108 perform some or all of the operations and / or functions described herein as associated with another circuit device. In some embodiments, two or more groups of circuit devices 102 to 108 are combined into a single module implemented in hardware, software, firmware, and / or combinations thereof.

[0040] In an example embodiment, pressure adjustment circuitry 114 may be configured to execute instructions stored in memory circuitry 104 or otherwise accessible to a processor for adjusting pressure sensor data based on the tilt angle of device 100 as described herein.

[0041] In an example embodiment, the fall detection circuitry 116 may be configured to execute instructions stored in the memory circuitry 104 or otherwise accessible to a processor for detecting whether a user of the device 100 has fallen using adjusted pressure sensor data.

[0042] Now refer to Figure 2 , Figure 2 Flowcharts illustrating example steps, processes, procedures, and / or operations according to various embodiments of the present disclosure are provided. Various methods described herein (including, for example, ...) Figure 2 The example methods shown can provide various technical benefits and improvements. Note that each box in the flowchart, and combinations of boxes in the flowchart, can be implemented using various means, such as hardware, firmware, circuitry, and / or other devices associated with the execution of software comprising one or more computer program instructions. For example, Figure 2 One or more of the processes described herein can be implemented by computer program instructions that can be stored in a non-transitory memory of an apparatus employing embodiments of the present disclosure and executed by a processor in that apparatus. These computer program instructions can direct a computer or other programmable apparatus to function in a particular manner, causing the instructions stored in a computer-readable memory to produce an article of writing that, when executed, implements the function specified in the flowchart.

[0043] As described above and as should be understood based on this disclosure, embodiments of this disclosure can be configured as methods, mobile devices, backend network devices, etc. Therefore, embodiments can include various means, comprising entirely hardware or any combination of software and hardware. Furthermore, embodiments can take the form of a computer program product on at least one non-transitory computer-readable storage medium having computer-readable program instructions (e.g., computer software) implemented in the storage medium. Similarly, embodiments can take the form of computer program code stored on at least one non-transitory computer-readable storage medium. Any suitable computer-readable storage medium can be utilized, including non-transitory hard disks, CD-ROMs, flash memory, optical storage devices, or magnetic storage devices.

[0044] Now refer to Figure 2 The illustration shows an example flowchart illustrating an example method 200 for adjusting sensor data from a waterproof sensor based on the tilt angle of a device, according to some embodiments of the present disclosure. In some embodiments, example method 200 may be implemented by an example device described herein, including but not limited to those described above. Figure 1 Example device 100 described.

[0045] Figure 2 The example method 200 shown in the diagram begins at step / operation 202. At step / operation 202, the processor (such as, but not limited to, those described above)... Figure 1 The processing circuitry 102 of the described device 100 determines the tilt angle of the device. In various embodiments, an accelerometer (such as, but not limited to, those described above) is used to determine the tilt angle. Figure 1 The accelerometer 112 of the described device 100 receives data and uses conventionally known calculations (such as using data from the zero-degree axis of the accelerometer (i.e., the axis with the same direction as gravity, which is usually called the Z-axis)) to determine the tilt angle of the device.

[0046] At step / operation 204, the processor (such as, but not limited to, the above-mentioned combination) Figure 1 The processing circuitry 102 of the described device 100 receives data from a pressure sensor (such as, but not limited to, those described above). Figure 1 The pressure sensor 110 of the described device 100 receives a pressure value. This pressure value may be referred to as the unadjusted pressure value because it has not been adjusted based on the tilt angle of the device.

[0047] At step / operation 206, the processor (such as, but not limited to, the above-mentioned combination) Figure 1The processing circuitry 102 and / or pressure adjustment circuitry 114 of the described device 100 determine a pressure adjustment value, which will be used to determine an adjusted pressure value (described further below). In various embodiments, the pressure adjustment value is based on (a) an inclination angle determined at step / operation 202 and (b) the slope value of pressure test data taken at each of two different test angles. In some embodiments, the two test angles are a zero-degree test angle and a 180-degree test angle, although different test angles may be used.

[0048] In various embodiments, pressure test data is determined during the manufacturing process. In various embodiments, multiple pressure readings (e.g., approximately 100) are taken when the device is positioned at zero degrees, and those readings are averaged; multiple pressure readings (e.g., approximately 100) are taken when the device is positioned at 180 degrees, and those readings are also averaged. In various embodiments, the difference between the average pressure readings at zero degrees and the average pressure readings at 180 degrees is calculated.

[0049] In various embodiments, the slope value is calculated based on the average of the pressure test readings taken at the zero-degree test angle and the average of the pressure test readings taken at the 180-degree test angle. Specifically, in some embodiments, the slope value is calculated as the average of the pressure test readings taken at the 180-degree test angle minus the average of the pressure test readings taken at the zero-degree test angle, divided by 180. If two different test angles (instead of zero and 180 degrees) are used, the slope value is calculated as the average of the pressure test readings taken at the second test angle minus the average of the pressure test readings taken at the first test angle, divided by the difference between the second and first test angles. In an example embodiment where the average pressure at 180 degrees is 0.15 hPa less than the pressure at zero degrees, the slope b = -0.15 / 180 = -0.000833.

[0050] In various embodiments, the pressure adjustment value is determined at step / operation 206 by multiplying the tilt angle determined at step / operation 202 by the slope value determined during the testing of the pressure sensor.

[0051] At step / operation 208, the processor (such as, but not limited to, the above-mentioned combination) Figure 1 The processing circuitry 102 and / or pressure adjustment circuitry 114 of the described device 100 use the pressure adjustment value determined at step / operation 206 to determine the adjusted pressure value. In various embodiments, the adjusted pressure value is determined by adding the pressure adjustment value determined at step / operation 206 to the unadjusted pressure value received at step / operation 204.

[0052] In various embodiments, example method 200 may run continuously on the device, or example method 200 may run only when, for example, a fall detection option is activated.

[0053] In various embodiments, the adjusted pressure value determined at step / operation 208 is used in the fall detection algorithm. In various embodiments, such a fall detection algorithm issues an alarm if it is determined that the user of the device has fallen. In various embodiments, such a fall detection algorithm determines whether the user of the device has fallen if the change in the adjusted pressure value exceeds a predetermined threshold.

[0054] in conclusion

[0055] Many modifications and other embodiments of these disclosures will occur to those skilled in the art who benefit from the teachings set forth in the foregoing description and associated figures. Although the figures show only certain components of the devices and systems described herein, it is to be understood that various other components may be used in conjunction with the system. Therefore, it is to be understood that this disclosure is not limited to the specific embodiments disclosed, and modifications and other embodiments are intended to be included within the scope of the appended claims. Furthermore, the steps in the methods described above may not necessarily occur in the order depicted in the figures, and in some cases, one or more of the depicted steps may occur substantially simultaneously, or additional steps may be involved. While specific terminology is used herein, it is used only in a generally descriptive sense and not for limiting purposes.

[0056] While various embodiments based on the principles disclosed herein have been shown and described above, modifications can be made thereto by those skilled in the art without departing from the spirit and teachings of this disclosure. The embodiments described herein are merely representative and not intended to be limiting. Many variations, combinations, and modifications are possible and are within the scope of this disclosure. The disclosed embodiments primarily relate to segmented broadband tympanometric techniques for true wireless stereo; however, those skilled in the art will recognize that this principle can be applied to any audio device. Alternative embodiments obtained by combining, integrating, and / or omitting features of the embodiments are also within the scope of this disclosure. Therefore, the scope of protection is not limited by the description set forth above.

[0057] In addition, the section headings used herein are provided or otherwise offer organizational clues in accordance with the recommendations of 37C.FR1.77. These headings should not limit or characterize the disclosure that may be set forth in any of the claims of this disclosure.

[0058] While this detailed description has illustrated some embodiments of the present disclosure, the appended claims cover other embodiments of the present disclosure that differ from the described embodiments according to various modifications and improvements. For example, the appended claims may cover any form of device that uses a waterproof pressure sensor or any type of sensor whose output can vary based on the tilt angle of the device, such as, but not limited to, mobile devices (e.g., mobile phones) and wearable devices (e.g., smartwatches), robots and robotic devices, and electronic cigarettes.

[0059] Within the appended claims, unless the specific terms “means for…” or “steps for…” are used in a given claim, the claims are not intended to be interpreted in accordance with paragraph 6 of 35 U.S.C. SC 112.

Claims

1. An apparatus comprising: Pressure sensor; Accelerometer; as well as A controller configured to determine the tilt angle of the device; The pressure sensor receives an unadjusted pressure value; a pressure adjustment value is determined based on the slope values ​​of pressure test data obtained at (a) the tilt angle and (b) at a first test angle and a second test angle different from the first test angle; and an adjusted pressure value is determined by adding the determined pressure adjustment value to the received unadjusted pressure value.

2. The device of claim 1, wherein the controller uses data received from the accelerometer to determine the tilt angle of the device.

3. The device according to claim 1, wherein the slope value is based on the average of a plurality of pressure test readings obtained at the first test angle and the average of a plurality of pressure test readings obtained at the second test angle.

4. The device according to claim 3, wherein the slope value is calculated as: the average of the plurality of pressure test readings obtained at the second test angle minus the average of the plurality of pressure test readings obtained at the first test angle, and then divided by the degree difference between the second test angle and the first test angle.

5. The device of claim 1, wherein the controller is further configured to: repeatedly determine the tilt angle of the device; receive the unadjusted pressure value from the pressure sensor; determine the pressure adjustment value based on (a) the tilt angle and (b) the slope value of the pressure test data obtained at the first test angle and the second test angle; and determine the adjusted pressure value by adding the determined pressure adjustment value to the received unadjusted pressure value.

6. The device of claim 5, wherein the controller is further configured to determine whether a user of the device has fallen based on changes in repeated determinations of the adjusted pressure value.

7. The device of claim 6, wherein if the change in the repeated determination of the adjusted pressure value exceeds a predetermined threshold, the controller determines that the user of the device has fallen.

8. The device of claim 1, wherein the device includes a wearable device.

9. The device according to claim 1, wherein the first test angle and the second test angle are 180 degrees apart.

10. The device according to claim 1, wherein the first test angle is zero degrees and the second test angle is 180 degrees.

11. A method for adjusting a pressure reading from a pressure sensor in a device, the method comprising: Determine the tilt angle of the device containing the pressure sensor; Receive the unadjusted pressure value from the pressure sensor; The pressure adjustment value is determined based on the tilt angle described in (a) and the slope values ​​of the pressure test data obtained at the first test angle and at a second test angle different from the first test angle. as well as The adjusted pressure value is determined by adding the determined pressure adjustment value to the received unadjusted pressure value.

12. The method of claim 11, wherein data received from the accelerometer of the device is used to determine the tilt angle of the device.

13. The method of claim 11, wherein the slope value is based on the average of a plurality of pressure test readings taken at the first test angle and the average of a plurality of pressure test readings taken at the second test angle.

14. The method of claim 13, wherein the slope value is calculated as: the average of the plurality of pressure test readings obtained at the second test angle minus the average of the plurality of pressure test readings obtained at the first test angle, and then divided by the degree difference between the second test angle and the first test angle.

15. The method of claim 11, further comprising repeating the following steps: Determine the tilt angle of the device; Receive the unadjusted pressure value from the pressure sensor; The pressure adjustment value is determined based on (a) the tilt angle and (b) the slope value of the pressure test data obtained at the first test angle and the second test angle; as well as The adjusted pressure value is determined by adding the determined pressure adjustment value to the received unadjusted pressure value.

16. The method of claim 15, further comprising determining whether the user of the device has fallen based on changes in repeated determinations of the adjusted pressure value.

17. The method of claim 16, wherein if the change in the repeated determination of the adjusted pressure value exceeds a predetermined threshold, it is determined that the user of the device has fallen.

18. The method of claim 11, wherein the device comprises a wearable device.

19. The method according to claim 11, wherein the first test angle and the second test angle are 180 degrees apart.

20. The method of claim 11, wherein the first test angle is zero degrees and the second test angle is 180 degrees.

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