Reduced power consumption sensor and associated method

Abstract

A sensing device is provided. For example, a sensing device may include a sensing element, a power source, and a processor that controls application of power from the power source to the sensing element and measures a response of the sensing element. The processor controls the application of power from the power supply to the sensing element according to an adaptive duty cycle in which power is repeatedly applied to the sensing element for a steady-state period, and two or more times of power is applied to the sensing element for an unsteady-state period each time the power is applied for the steady-state period. The steady-state time period is a time period long enough to cause the sensing element to achieve a steady-state response. The non-steady state time period is a time period insufficient for the sensing element to achieve a steady state response.

Description

Technical Field

[0001] Embodiments of the present disclosure relate generally to sensing devices, and more particularly to heated sensing devices. Background Art

[0002] Heated sensing devices, such as thermal conductivity gas sensing devices, require power to raise the sensing element to the desired operating temperature. In many applications, it is desirable to reduce the power to a low level, for example to extend battery life in portable devices. However, for some sensing device types, there is a trade-off between power and accuracy.

[0003] Such heated sensing devices are plagued by technical challenges and limitations. Through effort, ingenuity, and innovation, many of these identified problems have been addressed by developing solutions, including in the embodiments of the present disclosure, many examples of which are described in detail herein. Summary of the invention

[0004] Various implementations described herein relate to sensing devices and associated methods of reducing power consumption of sensing devices.

[0005] According to various embodiments of the present disclosure, a sensing device is provided. In some embodiments, the sensing device includes a sensing element, a power supply, and a processor, the processor controlling the application of power from the power supply to the sensing element and measuring the response of the sensing element to the application of power. The processor controls the application of power from the power supply to the sensing element according to an adaptive duty cycle, in which power is repeatedly applied to the sensing element during a steady-state time period, and each time power is applied during a steady-state time period, power is applied to the sensing element twice or more during a non-steady-state time period. The steady-state time period is a time period long enough for the sensing element to reach a steady-state response. The non-steady-state time period is a time period that is not enough for the sensing element to reach a steady-state response.

[0006] In some embodiments, the sensing element comprises a heated sensing element and the measured response is the temperature of the sensing element.

[0007] In some embodiments, the sensing element includes a thermopile, and the measured temperature of the sensing element is based on a voltage output of the thermopile.

[0008] In some embodiments, the processor applies power from the power source to the sensing element at predetermined time intervals.

[0009] In some embodiments, after each application of power, the processor compares the measured responses to detect changes from the previous application of power.

[0010] In some embodiments, after each application of power during the non-steady-state time period, the processor compares the measured response to the measured response of a corresponding portion of a previous steady-state time period to detect a change compared to the corresponding portion of the previous steady-state time period.

[0011] In some embodiments, if the processor detects a change from a previous power application during a non-steady-state time period, the processor controls the application of power from the power supply to the sensing element according to a fixed duty cycle, in which power is repeatedly applied to the sensing element only during the steady-state time period until a change from a previous power application is no longer detected.

[0012] In some embodiments, the non-steady-state time period is variable, and each non-steady-state time period ends if a change in the measured response is detected compared to a previous application of power.

[0013] In some embodiments, the non-steady-state time period is variable, and each non-steady-state time period ends when enough response data is measured to determine that there has been no change in the measured response from a previous application of power.

[0014] In some embodiments, the processor controls the display of the sensing element's response to the application of power based on one of: (i) the sensing element's response to the most recent application of power within a steady-state time period, (ii) an average of responses to previous applications of power within a steady-state time period, or (iii) a weighted average of responses to previous applications of power within a steady-state time period and a non-steady-state time period.

[0015] According to various embodiments of the present disclosure, a method for reducing the power consumption of a sensing device is provided. In some embodiments, the method includes controlling the application of power from the power supply of the sensing device to the sensing element of the sensing device by a processor of the sensing device; and measuring the response of the sensing element to the application of power by the processor. The processor controls the application of power from the power supply to the sensing element according to an adaptive duty cycle, in which power is repeatedly applied to the sensing element during a steady-state time period, and each time power is applied during the steady-state time period, power is applied to the sensing element twice or more during a non-steady-state time period. The steady-state time period is a time period long enough for the sensing element to reach a steady-state response. The non-steady-state time period is a time period that is not enough for the sensing element to reach a steady-state response.

[0016] The above exemplary invention content and other exemplary objects and / or advantages of the present disclosure and the manner of achieving these objects and / or advantages are further explained in the following detailed description and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The description of the exemplary embodiments may be read in conjunction with the accompanying drawings. It will be appreciated that, for simplicity and clarity of illustration, the elements shown in the figures are not necessarily drawn to scale unless otherwise described. For example, the dimensions of some of the elements may be exaggerated relative to other elements unless otherwise described. Embodiments incorporating the teachings of the present disclosure are shown and described with respect to the drawings presented herein, in which:

[0018] Figure 1 A block diagram showing an exemplary sensing device according to an exemplary embodiment of the present disclosure is shown;

[0019] Figure 2 It is shown Figure 1 a graph of a transient response of a heated sensing device of an exemplary sensing device of FIG. 1 ; and

[0020] Figure 3A and Figure 3B is a flow chart illustrating an exemplary method for operating an exemplary sensing device according to an exemplary embodiment of the present disclosure. DETAILED DESCRIPTION

[0021] Some embodiments of the present disclosure will be described more fully below with reference to the accompanying drawings, which illustrate some, but not all, embodiments of the present disclosure. In fact, these disclosures may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that the present disclosure satisfies applicable legal requirements. Throughout the content, similar reference numerals refer to similar elements.

[0022] As used herein, terms such as "front," "rear," "top," "bottom," "left," "right," and the like are used for illustrative purposes in the examples provided below to describe the relative positions of certain components or portions of components. Additionally, as will be apparent to one of ordinary skill in the art from this disclosure, the terms "substantially" and "approximately" indicate that the referenced element or associated description is accurate within an applicable engineering tolerance.

[0023] 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. It should be understood that the use of broad terms such as "comprising," "including," and "having" provides support for narrower terms such as "consisting of," "consisting essentially of," and "consisting essentially of."

[0024] The phrases "in one embodiment," "according to one embodiment," "in some embodiments," and the like generally mean that the particular feature, structure, or characteristic following the phrase may be included in at least one embodiment of the present disclosure, and may be included in more than one embodiment of the present disclosure (importantly, such phrases are not necessarily referring to the same embodiment).

[0025] Phrases such as "in one example," "according to one example," "in some examples," and the like generally mean that a particular feature, structure, or characteristic following the phrase may be included in at least one example of the present disclosure, and may be included in more than one example of the present disclosure (importantly, such phrases do not necessarily refer to the same example).

[0026] If the specification states that a component or feature "may", "can", "could", "should", "will", "preferably", "likely", "usually", "optionally", "for example", "as an example", "in some examples", "often" or "might" (or other such language) be included or have a property, the specific component or feature is not required to be included or have that property. Such components or features may be optionally included in some examples, or may be excluded.

[0027] The word “example” or “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any implementation described herein as “example” or “exemplary” is not necessarily to be construed as preferred or advantageous over other implementations.

[0028] The terms “electrically coupled,” “electrically coupled,” “in communication with,” “in electronic communication with,” or “connected” in this disclosure refer to two or more elements or components that are connected by wired means and / or wireless means such that signals, voltage / current, data and / or information can be transmitted to and / or received from these elements or components.

[0029] The term "component" may refer to an article, device, or apparatus that may include one or more surfaces, parts, layers, and / or elements. For example, an exemplary component may include one or more substrates that may provide one or more underlying layers for the component, and may include one or more elements that form part of atop a substrate and / or one or more elements that may be disposed on top of a substrate. In the present disclosure, the term "element" may refer to an article, device, or apparatus that may provide one or more functions.

[0030] The term "sensing device" or "sensing instrument" may refer to an article, device, or apparatus that measures a physical input from its environment and converts that input into data that can be interpreted by a person or a machine. Sensing devices can be used in a variety of applications, including detecting hazardous gases in an environment. Sensing devices can be mounted in a fixed location or can be portable so as to be carried by a user. Portable sensing devices are typically powered by batteries. One common type of sensing device is a thermal conductivity gas sensing device, which can measure the concentration of a gas based on the difference in thermal conductivity of different gases relative to air.

[0031] The terms "sensor", "sensor circuit", "sensing circuit", "sensing element", etc. may refer to one or more components, integrated circuits, etc. within a sensing device that interact with the environment, detect an input to be detected (e.g., whether a hazardous gas is present), and provide an output (e.g., a voltage) to another component in the sensing device for interpretation. In an exemplary thermal conductivity gas sensing device, the sensing circuit includes a resistive heating element and one or more thermopiles. When power is applied to the resistive heating element, a temperature gradient is generated across the thermopiles, thereby generating an output voltage corresponding to the temperature. When exposed to a gas with a higher thermal conductivity than air, the heat loss from the resistive heating element is greater, and therefore the temperature is lower. This temperature difference varies with gas concentration and can be detected, measured, and used to provide an alarm.

[0032] Heated sensing devices, such as thermal conductivity gas sensing devices, require power to raise the sensing element to the desired operating temperature. Since many such sensing devices are portable and therefore battery powered, it is desirable to reduce power consumption whenever possible to extend battery life. One way to reduce power consumption is to run the sensing circuit in a duty cycle rather than continuously. For example, a thermal conductivity sensing circuit that requires 20mW of power when operating continuously can be operated at a 10% duty cycle, taking a reading once per second, with an average power of 2mW, while still achieving the desired accuracy. However, running at a shorter duty cycle can reduce the accuracy of the readings to a level that may be unacceptable. Similarly, taking readings less frequently than once per second may make the response time too slow. Therefore, when powering a sensor using a fixed duty cycle, a trade-off needs to be made between power, accuracy, and response time.

[0033] To address the challenges and limitations associated with conventional sensing devices, various examples of the present disclosure may be provided. For example, various examples of the present disclosure may provide exemplary sensing devices, apparatuses, methods, and systems that have reduced power consumption compared to some conventional sensing devices. An exemplary sensing device provides power to a sensing circuit using an adaptive duty cycle as described herein. Embodiments of the present disclosure may be used with any suitable sensing device that can apply power using an adaptive duty cycle, including but not limited to heated sensing devices, such as heated metal oxide sensing devices, heated catalytic bead sensing devices, and thermal flow sensing devices.

[0034] Reference now Figure 1 , a block diagram of an exemplary sensing device 100 according to various embodiments of the present disclosure is provided. Figure 1 As shown, in some embodiments, the sensing device 100 includes a processor or processing circuit 102, a memory circuit 104, an input / output circuit 106, a communication circuit 108, a sensing circuit 110, and a power supply 116. In some embodiments, the sensing device 100 is configured to perform and carry out the operations described herein.

[0035] Although these components are described with respect to functional limitations, it should be understood that at least some specific implementations necessarily 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 circuits utilize the use of the same processor, memory, circuits, etc. to perform their associated functions, so that each set of circuits does not require duplicate hardware.

[0036] The processing circuit 102 can be embodied in a variety of different ways. In various embodiments, the use of the term "processor" or "processing circuit" should be understood to include a single-core processor, a multi-core processor, multiple processors within the sensing device 100, and / or one or more remote or "cloud" processors outside the sensing device 100. In some exemplary embodiments, the processing circuit 102 may include one or more processing devices configured to execute independently. Alternatively or additionally, the processing circuit 102 may include one or more processors configured in series via a bus to enable independent execution of operations, instructions, pipelining, and / or multithreading.

[0037] In an exemplary embodiment, the processing circuit 102 may be configured to execute instructions stored in the memory circuit 104 or otherwise accessible by the processor. Alternatively or additionally, the processing circuit 102 may be configured to perform hard-coded functions. Therefore, whether configured by hardware methods or software methods, or by a combination thereof, the processing circuit 102 may represent an entity (e.g., physically embodied in circuit form) that is capable of performing operations according to the embodiments of the present disclosure while being configured accordingly. Alternatively or additionally, the processing circuit 102 may be embodied as an executor of software instructions, and these instructions may specifically configure the processing circuit 102 to perform various algorithms embodied in one or more operations described herein when executing such instructions. In some embodiments, the processing circuit 102 includes hardware, software, firmware, and / or a combination thereof that performs one or more operations described herein.

[0038] In some embodiments, the processing circuit 102 (and / or a coprocessor or any other processing circuit that assists the processor or is otherwise associated with the processor) communicates with the memory circuit 104 via a bus for transferring information between components of the sensing device 100.

[0039] The memory or memory circuit 104 may be non-transitory and may include, for example, one or more volatile and / or non-volatile memories. In some embodiments, the memory circuit 104 includes or embodies an electronic storage device (e.g., a computer-readable storage medium). In some embodiments, the memory circuit 104 is configured to store information, data, content, applications, instructions, etc. for enabling the sensing device 100 to perform various operations and / or functions according to exemplary embodiments of the present disclosure.

[0040] Input / output circuit 106 may be included in sensing device 100. In some embodiments, input / output circuit 106 may provide output to a user and / or receive input from a user. Input / output circuit 106 may communicate with processing circuit 102 to provide such functions. Input / output circuit 106 may include one or more user interfaces. In some embodiments, the user interface may include a display including an interface presented as a web user interface, an application user interface, a user device, a backend system. In some embodiments, input / output circuit 106 also includes a keyboard, a mouse, a joystick, a touch screen, a touch area, a soft key, a microphone, a speaker or other input / output mechanism. Processing circuit 102 and / or input / output circuit 106 may be configured to control one or more operations and / or functions of one or more user interface elements by computer program instructions (e.g., software and / or firmware) stored on a processor-accessible memory (e.g., memory circuit 104, etc.). In some embodiments, input / output circuit 106 includes or utilizes a user-oriented application to provide input / output functions to a computing device and / or other display associated with a user.

[0041] The communication circuit 108 may be included in the sensing device 100. The communication circuit 108 may include any device, such as a device or circuit embodied in hardware or a combination of hardware and software, which is configured to receive and / or transmit data from / to a network and / or any other device, circuit or module that communicates with the sensing device 100. In some embodiments, the communication circuit 108 includes, for example, a network interface for implementing communication with a wired or wireless communication network. Additionally or alternatively, the communication circuit 108 may include one or more network interface cards, antennas, buses, switches, routers, modems and supporting hardware, firmware and / or software, or any other device suitable for implementing communication via one or more communication networks. In some embodiments, the communication circuit 108 may include a circuit for interacting with an antenna and / or other hardware or software to cause a signal to be transmitted via an antenna and / or to process a signal received via an antenna. In some embodiments, the communication circuit 108 enables data to be transmitted and / or received to and / or from a user device, one or more sensors and / or other external computing devices that communicate with the sensing device 100.

[0042] The sensing circuit 110 may include any suitable circuitry to provide the desired sensing functionality. In the case of a thermal conductivity gas sensing device, the sensing circuit 110 includes a resistive heating element 112 and one or more thermopiles 114 .

[0043] The power source 116 provides power to the sensing device 100, including providing power to the sensing circuit 110. The power source 116 may include any suitable power source, and for a portable sensing device, may include one or more batteries.

[0044] In some embodiments, two or more of the groups of circuits 102-110 are combinable. Alternatively or additionally, one or more of the groups of circuits 102-110 perform some or all of the operations and / or functions described herein as being associated with another circuit. In some embodiments, two or more of the groups of circuits 102-110 are combined into a single module embodied in the form of hardware, software, firmware, and / or a combination thereof.

[0045] Although the above description provides an exemplary sensing device 100, it should be noted that the scope of the present disclosure is not limited to the above description. In some examples, the exemplary sensing device 100 according to the present disclosure can be in other forms. In some examples, the exemplary sensing device 100 may include one or more additional and / or alternative elements, and / or may be used with Figure 1 The shown structures are different.

[0046] As described above, when power is applied to the resistive heating element of the thermal conductivity gas sensing device, a temperature gradient is generated across the thermopile, thereby generating an output voltage corresponding to the temperature. Figure 2 , which is a graph 200 illustrating the transient response of an exemplary thermal conductivity gas sensing device. Figure 2 Two different exemplary transient response curves are shown. (Note that in a real-world exemplary sensing device, these two different response curves will not exist at the same time because they show different gas concentrations. For illustrative purposes, both curves are included in Figure 2 ) Each response curve plots the thermopile voltage output in volts versus time in milliseconds. A first response curve 202 represents the thermopile voltage output when the ambient air is clean and there are no potentially harmful gases that the device is designed to detect. A second response curve 204 represents the thermopile voltage output when 2% (by volume) hydrogen is present. Figure 2 As shown, there is only a small difference in the thermopile voltage output between the two conditions. Figure 2 As further shown in , the thermopile voltage output curve is "noisy". Figure 2As further shown in , it takes time for the thermopile voltage output to ramp up to a steady-state condition where the thermopile voltage output is relatively constant. Taking into account the noise signal, the thermopile voltage output may not reach a completely steady-state condition. However, for the purposes of the embodiments of the present disclosure, a condition where the thermopile voltage output does not change by more than a suitable threshold (e.g., 5%) can be considered a steady state. Figure 2 In the example shown, the thermopile voltage output reaches a steady state approximately 15-20 milliseconds after power is supplied to the sensing circuit. Within approximately the first 6 milliseconds after power is supplied to the sensing circuit, any difference in the response curve cannot be discerned in the noise signal. From approximately 7 milliseconds after power is supplied to the sensing circuit until steady state is reached, differences in the response curve can be discerned, but the magnitude of the difference is difficult to determine due to the presence of noise. Therefore, although the difference in the response curve is discernible before steady state is reached, the magnitude of the difference (and the amount of gas detected) is less accurate. However, as further described below, this lower accuracy may be acceptable in certain circumstances to reduce power consumption.

[0047] The sensing devices of various embodiments of the present disclosure use adaptive duty cycles, where, for example, occasional, more accurate "long" duty cycles (where the sensing circuit is powered long enough to reach steady state) are interspersed with multiple shorter, less accurate "short" or "variable" duty cycles (which can be fixed length or variable length), thereby achieving a combination of good overall accuracy and lower power without affecting response speed.

[0048] The sensing devices of various embodiments of the present disclosure take advantage of the fact that sensing devices used for, for example, industrial safety gas detection generally do not need to provide high accuracy over short time scales, but only over longer averaging periods. For short time scales (e.g., less than 10 seconds to 1 minute), in some embodiments, accuracy may be affected if the sensor still responds quickly (e.g., within a few seconds) to larger potential hazardous concentrations. In some embodiments, for example, a more accurate (i.e., longer, steady-state) reading may be taken every 10 seconds to 1 minute, and multiple less accurate (e.g., shorter, non-steady-state) readings may be taken every 1 second, and acceptable accuracy and response time may be obtained with less power consumption.

[0049] In some embodiments, a weighted average of the readings (giving more weight to longer, more accurate readings) provides accurate readings over time, while shorter, more frequent, less accurate readings per second still provide a fast response. For example, if nine shorter, more frequent readings are taken for every longer, more accurate reading, each longer, more accurate reading may be weighted as high as nine shorter, more frequent readings.

[0050] In some embodiments, if shorter, more frequent readings detect a significant change in gas concentration, the sensor defaults to taking longer, more accurate readings more frequently (e.g., every 1 second) (without any shorter, less accurate readings) until the gas readings stabilize or fall back below a threshold.

[0051] In one specific example, a thermal conductivity sensing device has a thermal time constant of about 5 to 10 milliseconds. In such an example, to obtain an accurate, low-noise reading, it may be necessary to heat the sensing circuit for about 100 milliseconds to allow the reading time to stabilize and average enough data to filter out the noise. However, to obtain a less accurate reading in such an example, it may not be necessary to average a large amount of data or wait for the reading to reach a steady state. For example, the sensing circuit may be heated for only 10 milliseconds, and its transient response compared to the first 10 milliseconds of the most recent "full" (100 millisecond) reading. In such an example, if the transients are similar enough (e.g., within 0.1%), there is enough data to confirm that the gas concentration has not changed significantly.

[0052] In some embodiments, an adaptive approach may also be used wherein, instead of operating for a specified time, the sensing circuit may be heated and its transients continuously monitored until there is sufficient data to determine whether the gas concentration has changed significantly, at which point power to the sensing circuit heater may be shut off and the processing circuitry placed into a sleep mode, thereby reducing power to nearly zero.

[0053] In some embodiments, a more accurate average reading can be obtained by averaging only longer readings, giving an accurate reading that is updated less frequently (e.g., once every 10 seconds). Alternatively, more preferably, in some embodiments, a moving average is used. In some embodiments, the average is weighted in proportion to the "on" time of each measurement, so that the overall average reading remains accurate while updated readings are obtained more frequently (e.g., once every 1 second).

[0054] In the embodiments of the present disclosure, while maintaining the desired accuracy and response speed, the reduction in power can be significant. For example, the exemplary sensing circuit can consume about 20 milliwatts of power when it is continuously powered. If the same exemplary sensing circuit has a pulse duration of 100 milliseconds (i.e., fixed duty cycle) in every 1 second, the sensing circuit will consume an average value of 2 milliwatts. If the same exemplary sensing circuit has a pulse duration of 10 milliseconds (i.e., fixed duty cycle, but the readings are all short readings) in every 1 second, the sensing circuit will consume an average value of 0.2 milliwatts, but the accuracy and noise will be unacceptable. Therefore, according to the embodiments of the present disclosure, if the same exemplary sensing circuit has a pulse duration of 100 milliseconds for every 10 readings per second and a pulse duration of 10 milliseconds for the other 9 readings per second, the average power consumed will be 0.38 milliwatts and the accuracy will be acceptable. This is just an example, and the actual duty cycle can be customized according to the accuracy and response time requirements of the application.

[0055] Now refer to Figure 3A and Figure 3B , which provides a flowchart showing exemplary steps, processes, procedures and / or operations according to various embodiments of the present disclosure. The various methods described herein (including, for example, Figure 3A and Figure 3B The method shown) can provide various technical benefits and improvements.

[0056] Reference now Figure 3A and Figure 3B , showing an exemplary method 300. In some embodiments, the exemplary method includes a method for reducing power consumption of a sensing device. At step / operation 302, a processor (such as but not limited to the above combined Figure 1 The processing circuit 102 of the exemplary sensing device 100 described above sets a counter to 1. In some embodiments, this counter is used to track the number of shorter readings, as several shorter readings (eg, 9) are completed for each longer reading.

[0057] At step / operation 304, a processor (such as but not limited to the above combined Figure 1 The processing circuit 102 of the exemplary sensing device 100 described above resets and starts a cycle timer. In some embodiments, the cycle timer is used to determine when each new reading (shorter and longer reading) should start. For example, the cycle timer (which can be a count-up timer or a count-down timer) can be 1 second, so that a new reading (shorter or longer) starts every 1 second.

[0058] At step / operation 306, a processor (such as but not limited to the above combined Figure 1The processing circuit 102 of the exemplary sensing device 100 applies power to the sensing circuit for a predetermined short period of time. For example, the short period of time may be 10 milliseconds.

[0059] At step / operation 308, a processor (such as but not limited to the above combined Figure 1 The processing circuit 102 of the exemplary sensing device 100 described herein increments the counter by 1 because a shorter reading has been completed.

[0060] At step / operation 310, a processor (such as but not limited to the above combined Figure 1 The processing circuit 102 of the exemplary sensing device 100 receives and stores the output (eg, the thermopile voltage) from the sensing circuit.

[0061] At step / operation 312, a processor (such as but not limited to the above combined Figure 1 The processing circuit 102 of the exemplary sensing device 100 described analyzes the output from step / operation 310 and determines whether there is a change in the output from the sensing circuit. As described above, in some embodiments, this is determined by comparing the output to a corresponding portion of a recent longer reading (e.g., the previous 10 milliseconds).

[0062] If it is determined at step / operation 312 that there is a change in the output from the sensing circuit, the method proceeds to step / operation 314. At step / operation 314, a processor (such as, but not limited to, the above-described combination of Figure 1 The processing circuit 102 of the exemplary sensing device 100 described above sets an alarm. In some embodiments, setting an alarm may involve triggering an auditory and / or visual indication to the user. The method then proceeds to the following description Figure 3B Step / operation 332 above.

[0063] If it is determined at step / operation 312 that there is no change in the output from the sensing circuit, the method proceeds to step / operation 316. At step / operation 316, a processor (such as, but not limited to, the above in conjunction with Figure 1 The processing circuit 102 of the exemplary sensing device 100 described above determines whether the cycle timer has elapsed. If the cycle timer has not elapsed, the method remains in step / operation 316 until the cycle timer has elapsed.

[0064] If it is determined at step / operation 316 that the cycle timer has elapsed, the method proceeds to step / operation 318. At step / operation 318, a processor (such as, but not limited to, the above-described combination Figure 1The processing circuit 102 of the exemplary sensing device 100 described above determines whether a counter has reached a predetermined number (eg, 9) of shorter readings to be completed for each longer reading.

[0065] If it is determined at step / operation 318 that the counter has not reached the predetermined number of shorter readings, the method returns to step / operation 304 to start another shorter reading. In some embodiments, the method repeats steps / operations 304-318 until it is determined at step / operation 318 that the counter has reached the predetermined number of shorter readings.

[0066] If it is determined at step / operation 318 that the counter has reached a predetermined number of shorter readings, the method proceeds to step / operation 320. At step / operation 320, a processor (such as, but not limited to, the processor described above in conjunction with Figure 1 The processing circuit 102 of the exemplary sensing device 100 described above resets and starts a cycle timer (ie, the cycle timer mentioned in step / operation 304).

[0067] At step / operation 322, a processor (such as but not limited to the above combined Figure 1 The processing circuit 102 of the exemplary sensing device 100 applies power to the sensing circuit for a predetermined longer period of time. For example, the longer period of time may be 100 milliseconds.

[0068] At step / operation 324, a processor (such as but not limited to the above combined Figure 1 The processing circuit 102 of the exemplary sensing device 100 receives and stores the output (eg, the thermopile voltage) from the sensing circuit.

[0069] At step / operation 326, a processor (such as but not limited to the above combined Figure 1 The processing circuit 102 of the exemplary sensing device 100 described analyzes the output from step / operation 324 and determines whether there is a change in the output from the sensing circuit. As described above, in some embodiments, this can be determined by comparing the output to the most recent longer reading, to an average of (some predetermined number of) previous longer readings, or to a weighted average of previous longer and shorter readings.

[0070] If it is determined at step / operation 326 that there is a change in the output from the sensing circuit, the method proceeds to step / operation 328. At step / operation 328, a processor (such as, but not limited to, the above in conjunction with Figure 1 The processing circuit 102 of the exemplary sensing device 100 described above sets an alarm. In some embodiments, setting an alarm may involve triggering an auditory and / or visual indication to the user. The method then proceeds to the following description Figure 3BStep / operation 332 above.

[0071] If it is determined at step / operation 326 that there is no change in the output from the sensing circuit, the method proceeds to step / operation 330. At step / operation 330, a processor (such as, but not limited to, the above-described combination of Figure 1 The processing circuit 102 of the exemplary sensing device 100 described above determines whether the cycle timer has elapsed. If the cycle timer has not elapsed, the method remains in step / operation 330 until the cycle timer has elapsed.

[0072] If it is determined at step / operation 330 that the cycle timer has elapsed, the method proceeds to step / operation 302. At step / operation 302, a processor (such as, but not limited to, the above-described combination Figure 1 The processing circuit 102 of the exemplary sensing device 100 described sets the counter to 1. In some embodiments, the method repeats steps / operations 302-330 unless a change is detected at step / operation 312 or step / operation 326.

[0073] If a change is detected at step / operation 312 or step / operation 326, then in some embodiments, the method will switch to performing only longer readings until a change is no longer detected. In this regard, at step / operation 332, a processor (such as, but not limited to, the above-described method in conjunction with Figure 1 The processing circuit 102 of the exemplary sensing device 100 described above determines whether the cycle timer has elapsed. If the cycle timer has not elapsed, the method remains in step / operation 332 until the cycle timer has elapsed.

[0074] If it is determined at step / operation 332 that the cycle timer has elapsed, the method proceeds to step / operation 334. At step / operation 334, a processor (such as, but not limited to, the above-described combination Figure 1 The processing circuit 102 of the exemplary sensing device 100 described above resets and starts a cycle timer (ie, the cycle timer mentioned in step / operation 304).

[0075] At step / operation 336, a processor (such as but not limited to the above combined Figure 1 The processing circuit 102 of the exemplary sensing device 100 applies power to the sensing circuit for a predetermined longer period of time. For example, the longer period of time may be 100 milliseconds.

[0076] At step / operation 338, a processor (such as but not limited to the above combined Figure 1 The processing circuit 102 of the exemplary sensing device 100 receives and stores the output (eg, the thermopile voltage) from the sensing circuit.

[0077] At step / operation 340, a processor (such as but not limited to the above combined Figure 1 The processing circuit 102 of the exemplary sensing device 100 analyzes the output from step / operation 338 and determines whether a change still exists in the output from the sensing circuit (ie, whether a potentially harmful gas is still present).

[0078] If it is determined at step / operation 340 that there is still a change in the output from the sensing circuit, the method proceeds to step / operation 342 and continues the alarm. The method then proceeds to step / operation 332. In some embodiments, the method repeats steps / operations 332-340 unless a change is no longer detected at step / operation 340.

[0079] If it is determined at step / operation 340 that there is no longer a change in the output from the sensing circuit, the method proceeds to step / operation 344. At step / operation 344, a processor (such as, but not limited to, the above-described combination of Figure 1 The processing circuit 102 of the exemplary sensing device 100 described above resets the alarm. In some embodiments, resetting the alarm may involve stopping any audible and / or visual indication to the user.

[0080] At step / operation 346, a processor (such as but not limited to the above combined Figure 1 The processing circuit 102 of the exemplary sensing device 100 described above determines whether the cycle timer has elapsed. If the cycle timer has not elapsed, the method remains in step / operation 346 until the cycle timer has elapsed.

[0081] If it is determined at step / operation 330 that the cycle timer has elapsed, the method proceeds to Figure 3A Step / operation 302 of the above. At step / operation 302, a processor (such as but not limited to the above combined Figure 1 The processing circuit 102 of the exemplary sensing device 100 described sets the counter to 1. In some embodiments, the method repeats steps / operations 302-330 unless a change is detected at step / operation 312 or step / operation 326.

[0082] The operations and processes described herein support a combination of means for performing the specified functions and a combination of operations for performing the specified functions. It will be understood that one or more operations and a combination of operations can be implemented by a computer system based on dedicated hardware that performs the specified functions or a combination of dedicated hardware and computer instructions.

[0083] In some example embodiments, some of the operations herein may be modified or further amplified as described below. In addition, in some embodiments, additional optional operations may also be included. It should be understood that each of the modifications, optional additions, or amplifications described herein may be included in the operations herein, either individually or in combination with any other features described herein.

[0084] The foregoing method and process descriptions are provided only as illustrative examples, and are not intended to require or imply that the steps of the various embodiments must be performed in the order presented. As will be appreciated by those skilled in the art, the order of steps in the above-described embodiments may be performed in any order. Words such as "afterwards," "then," "next," and the like are not intended to limit the order of the steps; these words are simply used to guide the reader through the description of the method. In addition, for example, any reference to a claim element in the singular form using the articles "a," "an," or "the" should not be construed as limiting the element to the singular and, in some cases, may be construed in the plural.

[0085] Although various embodiments according to the principles disclosed herein have been shown and described above, modifications may be made thereto by those skilled in the art without departing from the teachings of the present disclosure. The embodiments described herein are representative only and are not intended to be limiting. Many variations, combinations and modifications are possible and are within the scope of the present disclosure. Alternative embodiments obtained by merging, integrating and / or omitting the features of one or more embodiments are also within the scope of the present disclosure. Therefore, the scope of protection is not limited by the description given above, but by the following claims, which include all equivalents of the subject matter of the claims. Each claim is incorporated into the specification as further disclosure, and the claims are embodiments of the present disclosure. In addition, any of the above advantages and features may relate to specific embodiments, but the application of such published claims should not be limited to methods and structures that achieve any or all of the above advantages or have any or all of the above features.

[0086] In addition, the section headings used herein are intended to be consistent with the recommendations of 37 CFR § 1.77 or to provide organizational clues. These headings should not limit or characterize the disclosures set forth in any claims that may be published from this disclosure. For example, the description of the technology in the "background technology" should not be interpreted as an admission that a certain technology is prior art to any disclosure in this disclosure. "Summary of the invention" should also not be considered as a limiting characterization of the disclosure set forth in the published claims. In addition, any reference to the singular "disclosure" or "embodiment" in this disclosure should not be used to prove that there is only one novel point in this disclosure. According to the limitations of multiple claims published from this disclosure, multiple embodiments of the disclosure may be set forth, and such claims accordingly define the disclosures protected by them and their equivalents. In all cases, the scope of these claims should be considered in accordance with the present disclosure on the merits of the claims themselves, and should not be limited by the titles set forth herein.

[0087] Moreover, without departing from the scope of the present disclosure, the systems, subsystems, devices, techniques and methods described and shown in a discrete or separate manner in various embodiments may be combined or integrated with other systems, modules, techniques or methods. Other devices or components shown or discussed as being connected or communicating with each other may be indirectly connected through some intermediate devices or components, whether such connection is made electrically, mechanically or otherwise. Other examples of changes, substitutions and modifications may be determined by those skilled in the art and may be made without departing from the scope disclosed herein.

[0088] Those skilled in the art to which these embodiments belong will think of many modifications and other embodiments of the disclosure set forth herein, which have the benefit of the teachings presented in the foregoing description and the associated drawings. Although the drawings only show certain components of the devices and systems described herein, various other components can be used in combination with the components and structures disclosed herein. Therefore, it should be understood that the present 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. For example, various elements or components may be combined, rearranged or integrated into another system, or certain features may be omitted or not implemented. In addition, the steps in any of the above methods may not necessarily occur in the order depicted in the drawings, and in some cases, one or more of the depicted steps may occur substantially simultaneously, or may involve additional steps. Although specific terms are used herein, they are used only in a general and descriptive sense, not for the purpose of limitation.

Claims

1. A sensing device, comprising: Sensing element; power supply; and a processor that controls application of power from the power source to the sensing element and measures a response of the sensing element to the application of power; wherein the processor controls the application of the power from the power source to the sensing element according to an adaptive duty cycle in which power is repeatedly applied to the sensing element during a steady-state period, and in which power is applied to the sensing element two or more times during a non-steady-state period for each application of power during the steady-state period; wherein the steady-state time period is a time period long enough for the sensing element to reach a steady-state response; and The non-steady-state time period is a time period that is insufficient for the sensing element to reach a steady-state response.

2. The sensing device of claim 1, wherein the sensing element comprises a heated sensing element and the measured response is the temperature of the sensing element.

3. The sensing device of claim 2, wherein the sensing element comprises a thermopile; and The measured temperature of the sensing element is based on a voltage output of the thermopile.

4. The sensing device of claim 1, wherein after each application of power, the processor compares the measured responses to detect changes compared to a previous application of power.

5. The sensing device of claim 4, wherein after each application of power during a non-steady-state time period, the processor compares the measured response with the measured response of a corresponding portion of a previous steady-state time period to detect a change compared to the corresponding portion of the previous steady-state time period.

6. A sensing device according to claim 4, wherein if the processor detects a change compared to a previous power application during a non-steady-state time period, the processor controls the power application from the power supply to the sensing element according to a fixed duty cycle, in which power is repeatedly applied to the sensing element only during the steady-state time period until a change compared to the previous power application is no longer detected.

7. The sensing device according to claim 4, wherein the non-steady-state time period is variable; and Each non-steady-state time period ends if a change in the measured response compared to a previous application of power is detected.

8. The sensing device according to claim 4, wherein the non-steady-state time period is variable; and Each non-steady-state time period ends wherein sufficient response data is measured to determine that there has been no change in the measured response from a previous application of power.

9. A sensing device according to claim 1, wherein the processor controls the display of the response of the sensing element to the application of power based on one of the following items: (i) the response of the sensing element to the most recent application of power within a steady-state time period, (ii) an average of the responses to previous applications of power within a steady-state time period, or (iii) a weighted average of the responses to previous applications of power within a steady-state time period and a non-steady-state time period.

10. A method for reducing power consumption of a sensing device, the method comprising: controlling, by a processor of the sensing device, application of power from a power source of the sensing device to a sensing element of the sensing device; as well as measuring, by the processor, a response of the sensing element to the application of the electrical power; wherein the processor controls the application of the power from the power source to the sensing element according to an adaptive duty cycle in which power is repeatedly applied to the sensing element during a steady-state period, and in which power is applied to the sensing element two or more times during a non-steady-state period for each application of power during the steady-state period; wherein the steady-state time period is a time period long enough for the sensing element to reach a steady-state response; and The non-steady-state time period is a time period that is insufficient for the sensing element to reach a steady-state response.

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