SCIENTIFIC INSTRUMENT

PRIORITY CLAIM

This application claims priority of U.S. Provisional Application

Serial No. 62/086,685, filed on December 2, 2014. U.S. Provisional Application Serial No. 62/086,685 is incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present invention relates generally to scientific instruments, and more specifically to methods and apparatuses for heating and/or de-icing of scientific instruments in harsh environments.

BACKGROUND

Scientific research is often conducted in remote areas of the planet where, or when, freezing conditions are present all, or most of, the time. Such remote areas include remote locations where it is desirable to perform measurements in unattended, unmanned ways.

For example, spatial and temporal data coverage of Arctic ecosystem-atmosphere carbon (C) exchange is sparse and year-round coverage is lacking. The scarcity of continuous, year-round measurements in the Arctic relates to the extreme environmental conditions, especially in winter, relative lack of infrastructure, and the remote nature of representative Arctic sites.

Spatial and temporal data coverage can be provided by a combination of a gas analyzer and a sonic anemometer. A range of sonic anemometers have been used in the Arctic, but a major challenge for measuring fluxes in these regions is their performance in extreme weather conditions when water, snow, and ice can block the sonic signal of the sonic anemometer's transducers. In order to measure fluxes outside the summer period, the transducers of the sonic anemometer need to be maintained ice-free.

Heating systems for sonic anemometers have generally utilized heating tape wrapped around the anemometer, or hot film devices. An example commercially available 3D-anemometer providing a self-heating system is the uSonic-3 Class A anemometer, manufactured by METEK GmbH, Helmshorn, Germany. Such anemometers can be heated continuously, or activated based on absolute temperature. However, heating scientific instruments requires significant power, and the heating itself can bias results from the scientific instrument.

There is therefore a need in the art for automatically heated scientific instruments and methods for operating such instruments.

SUMMARY

In alternative embodiments, provided are automatic heating apparatuses for heating a scientific instrument comprising a data quality measurement module for measuring quality of collected data; a heater for heating the scientific instrument; and an activation switch for activating the heater when the measured quality of the collected data is less than a predetermined value.

In alternative embodiments, and in combination with any or all of the above, the automatic heating apparatus further comprises a deactivation switch for deactivating the heater when the measured quality of the collected data reaches or exceeds the predetermined value.

In alternative embodiments, and in combination with any or all of the above, the automatic heating apparatus further comprises a status recording module for indicating that the heater is heating the scientific instrument.

In alternative embodiments, and in combination with any or all of the above, the automatic heating apparatus further comprises a status recording module for indicating that collected data was collected during heating. In alternative embodiments, and in combination with any or all of the above, the scientific instrument comprises a sonic anemometer.

In alternative embodiments, and in combination with any or all of the above, the heater comprises a sonic heating element.

In alternative embodiments, and in combination with any or all of the above, the scientific instrument comprises a sonic anemometer; the heater comprises a sonic heating element; and the activation switch is configured to allow power to be provided to the heater only when the measured quality of the collected data is less than the predetermined value.

In alternative embodiments, and in combination with any or all of the above, wherein the activation switch comprises: a switch port; a relay coupled to said switch port; and a power supply coupled to and configured to power the heater, said power supply being coupled to said relay.

In alternative embodiments, and in combination with any or all of the above, the data quality measurement module is configured to measure quality of collected data by determining whether the collected data is within a predetermined range.

In alternative embodiments, and in combination with any or all of the above, the heater comprises a de-icing capability.

In alternative embodiments, and in combination with any or all of the above, provided are methods for automatically heating a scientific instrument, the method comprising: collecting data from the scientific instrument; determining whether data quality of the collected data is less than a predetermined value; and activating a heater to heat the scientific instrument if the data quality is less than the predetermined value.

In alternative embodiments, and in combination with any or all of the above, the method further comprises deactivating the heater if the data quality meets or exceeds the predetermined value.

In alternative embodiments, and in combination with any or all of the above, said determining whether data quality of the collected data is less than a predetermined value comprises: collecting training data from the scientific instrument when one or more transducers of the scientific research equipment is blocked; and determining a range within which data quality is low based on the collected training data.

In alternative embodiments, and in combination with any or all of the above, the method further comprises blocking the one or more transducers before said collecting training data.

In alternate embodiments, and in combination with any or all of the above, said determining whether data quality of the collected data is less than a predetermined value comprises one or more of determining whether the collected data is within a predetermined closed-ended or open ended range, performing wavelet analysis, or performing statistical analysis.

In alternative embodiments, and in combination with any or all of the above, the method further comprises recording a heating status for the scientific research equipment if the data quality is less than the predetermined value.

In alternative embodiments, and in combination with any or all of the above, the scientific research equipment comprises a sonic anemometer, and the heater comprises a sonic heater.

In alternative embodiments, and in combination with any or all of the above, said activating the heater comprises allowing current to flow to the heater.

In alternative embodiments, and in combination with any or all of the above, provided are automatically heated sonic anemometers comprising: a transducer configured for detecting temperature and fluid flow; a data quality measurement module coupled to said transducer for measuring quality of collected data; a heater coupled to said transducer for heating the transducer; an activation switch configured to activate the heater when the measured quality of the collected data is less than a predetermined value; a deactivation switch configured for deactivating the heater when the measured quality of the collected data reaches or exceeds the predetermined value; and a status recording module coupled to said data quality measurement module for indicating that the heater is heating the transducer.

In alternative embodiments, and in combination with any or all of the above, the automatically heated sonic anemometer further comprises: a power supply for the heater; wherein said activation switch is configured to allow power to said heater when the measured quality of the collected data reaches or exceeds the predetermined value; and wherein said deactivation switch is configured to cut off power to said heater when the measured quality of the collected data reaches or exceeds the predetermined value.

The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.

All publications, patents, patent applications cited herein are hereby expressly incorporated by reference for all purposes.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGURE 1 shows a sonic anemometer and an apparatus for heating the sonic anemometer according to an embodiment of the invention;

FIG. 2 shows an example process for automatically heating the sonic anemometer; and

FIG. 3 shows temperature controls installed on a METEK uSonic3 Class A sonic anemometer in two setup configurations: A, where the sonic anemometer was initially deactivated and then continuously heated; and B, where the sonic anemometer was heated according to an example method. Thermocouples are attached to the sonic anemometers to control the temperature in corresponding locations (upper spar: red lines; lower spar: blue lines; air temperature: black line). BEST MODE OF CARRYING OUT THE INVENTION

Systems and methods for automatically heating an instrument, such as a sonic anemometer, based on a quality of collected data are provided. Automatically heated sonic anemometers and methods for automatically heating sonic anemometers are also provided according to example embodiments. Such systems and methods are particularly useful for remotely located scientific instruments that cannot easily be manually operated, and where power may be limited.

As a non-limiting example, scientific instruments for performing unmanned temperature, wind, or other measurements in remote areas where ice and freezing conditions occur for substantial portions of the year can be automatically heated and/or de-iced. By automatically and selectively heating a scientific instrument such as a sonic anemometer, more accurate measurements can be obtained from the sonic anemometer even when the sonic anemometer is located in a remote location, where measurements are typically or necessarily performed in unattended, unmanned ways. Further, required power for heating the equipment can be reduced.

By contrast, conventionally scientific instruments may be continuously operated, or activated only based on whether temperatures drop below a predetermined value. Example methods and systems can apply heating only when needed, and record when such heating is occurring. Such recording is desirable because heating of scientific instruments may otherwise affect measured values from the scientific instrument by creating a bias in the sign and magnitude of flux measurements or other data. Heating of such scientific instruments may also be switched off automatically when not needed. Additionally, the increase in temperature of the scientific instrument (e.g., increased temperature of a bar of the sonic anemometer) when heated continuously, and the resulting potential to bias the data, is limited or avoided when an intermittent heating is applied.

An example automatic heating apparatus for a scientific instrument includes a data quality measurement module for measuring quality of collected data, a heater for heating the scientific instrument, and an activation switch for activating the heater when the measured quality of the collected data is less than a predetermined value. In some embodiments, the system further includes a deactivation switch for deactivating the heater when the measured quality of the collected data reaches a predetermined value.

In a particular example embodiment, a sonic anemometer can be heated in response to quality of data generated by the anemometer. By contrast, some conventional sonic anemometers are heated only response to an absolute temperature.

The term "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.

Preferred embodiments will now be discussed with respect to the drawings. The drawings include schematic figures that are not to scale, which will be fully understood by skilled artisans with reference to the accompanying description. Features may be exaggerated for purposes of illustration. From the preferred embodiments, artisans will recognize additional features and broader aspects of the invention.

FIG. 1 shows an example apparatus 10 for automatically heating a scientific instrument. In the example embodiment shown in FIG. 1 , the scientific instrument is embodied in a sonic anemometer 12. As a non-limiting example, the sonic anemometer 12 can be disposed in a tower for measuring fluid flow in a remote environment. A particular example sonic anemometer is the METEK uSonic-3 Class A sonic anemometer, manufactured by METEK GmbH, Helmshorn, Germany.

The sonic anemometer 12 includes transducers 14 for generating data representing sonic temperature T _s as well as wind speed and direction measurements for the environment in which the apparatus 10 is located. The transducers 14 are coupled to a processor 16 via a signal path 18, such as a serial or direct connection. An example processor 16 is embodied in a datalogger, a particular example of which is a Campbell CR3000 Micro logger, manufactured by Campbell Scientific, Logan, UT. Suitable power supplies (not shown) are provided to power the sonic anemometer 12 and the processor 16.

The processor 16 includes a data collection module 18 for recording and collecting data from the sonic anemometer 12 and a data quality measurement module 20 for measuring a quality of the collected data. The processor 16 may be coupled to one or more additional processors 22 for downstream processing, equipment control, network transmission, etc. A particular example of an additional processor 22 includes an embedded computer 24 coupled via lines 26 to a network switch 28 and modem 30, as well as a power supply 32. The additional processor 22 may be disposed within a suitable enclosure 34, such as a cooler case, for use within a remote environment.

To automatically heat the sonic anemometer 12, a heater 36 may be coupled to or integrated with the sonic anemometer. Example heaters 36 for the sonic anemometer 12 include heating tape or hot film wrapped around or formed on the transducers 14, heating cables or lines covering the transducers or support arms, or an integrated sonic heating element, such as that provided in the METEK uSonic-3 Class A sonic anemometer. Preferably, the heater 36 includes a de-icing capability for removing ice that forms on the transducers 14 of the sonic anemometer 12. The heater 36 may be powered by a separate power supply (not shown) or by the same power supply as the sonic anemometer 12 in some embodiments.

The heater 36, whether separate or integrated, is coupled to an activation switch 38 and deactivation switch 40 for activating and deactivating heating, respectively. The activation switch 38 and the deactivation switch 40 can be embodied in the same switch (e.g., an on/off switch, closed-loop control, etc.) in some embodiments. The activation switch 38 and the deactivation switch 40 can be provided within a signal path of a receiver of output signals from the sonic anemometer 12. A particular example activation switch 38 and deactivation switch 40 is embodied in a switch port that is disposed on (or coupled to) the processor 16. For example, if the processor 16 is embodied in a datalogger, the switch port can be provided on the datalogger. The switch port is in turn coupled to a relay (e.g., a normally closed solid state DC relay) linked to a power supply 41 for the heater 36. In an example configuration, a sonic anemometer with integrated heating can internally be powered "on," but power is selectively supplied to the heater via the activation switch 38 and the deactivation switch 40 for controlling the heater's operation.

The activation switch 38 is configured to activate the heater 36 when the data quality measurement module 20 determines that the measured quality of collected data, e.g., from the data collection module 18, is less than a predetermined value; i.e., low data quality, such as when the transducers 14 are blocked by ice, snow, and/or water. The data quality measurement module 20 can determine low data quality in various ways. For example, if the collected data from the data collection module 20 (e.g., the original data output from the analog output of the sonic anemometer 12) falls within a predetermined range indicating low data quality (or alternatively, falls outside of a predetermined range indicating acceptable data quality), the data quality can be determined to be less than a predetermined value. This predetermined range can be established either before operation of the sonic anemometer 12 in its intended environment (e.g., by intentionally blocking the transducers 14, such as with a panel, and observing collected data), or established during operation (e.g., by observing collected data during ice, snow, and/or water blockage). Such ranges may be open-ended (including a single threshold) or closed-ended (including upper and lower limits). Other example methods for determining low data quality include, but are not limited to, statistical sampling (e.g., to detect unusual data changes), wavelet analysis (e.g., to detect a signature for ice or other blockage), etc. Simpler data quality detection methods may require lower processing resources.

Similarly, the deactivation switch 40 is preferably configured for deactivating the heater 36 when the data quality measurement module 20 determines that the measured quality of collected data, e.g., from the data collection module 18, reaches or exceeds the predetermined value, such as via one or more methods described above. If the activation switch 38 is configured to activate the heater 36 only when the data quality is less than the predetermined value, the activation switch 38 can also provide deactivation.

The activation switch 38 and deactivation switch 40 (if a separate switch is provided) can be controlled via instructions for the processor 16. Alternatively, the activation switch 38 and deactivation switch 40 can be embodied in electrical devices, e.g., filters and switches, coupled to the transducers 14, for activation or deactivation based on electrical signals.

The processor 16 preferably further includes a status recording module 42 for recording a status of the sonic heating (e.g., on or off) in the data stream provided by the data collection module 18. In an example embodiment, the status recording module 42 records, along with the collected data, a data flag (0 = heating off, 1 = heating on). This indicates when the sonic anemometer 12 is being heated, and thus when the sonic measurements may be affected. The recording data can thus be adjusted or removed later if needed. The status recording module 42 can be implemented via instructions for the processor 16, a particular example of which is Campbell datalogger CRBasics code, or by other methods as will be appreciated by those of ordinary skill in the art.

FIG. 2 shows an example method of operation for the apparatus 10. The apparatus 10 may be trained (step 50) as described above to provide a range or other indication for determining that data quality is below a predetermined value. For example, the sonic anemometer 12 may be activated and fully or partially blocked, e.g., selectively covered by a panel, permitted to ice, etc. During operation, the (blocked) transducers 14 generate one or more output signals, resulting in training data collected by the data collection module. This training data can be used to determine a data range (open-ended or closed-ended) when the transducers 14 are covered, indicating low data quality. For example, the range established by the training data, with or without an adjustment to increase or narrow the range, can provide a range for low data quality. Training (step 50) may be performed periodically to update this range (or other indication).

After training (step 50), the sonic anemometer 12 is activated (step

52), such as in an environment to be measured by the sonic anemometer. The heater 36 is set to an "OFF" or "LOW" state (step 54). In an example method of operation in which the sonic anemometer 12 includes an integrated heater 36, the heater 36 may be internally set to "ON" so that the system is internally on consistently, but without current (or low current) being supplied to the heater. In other example methods of operation, the heater 36, whether external or internal, may be more directly set to "OFF" or "LOW."

The transducers 14 generate one or more analog output signals, which produce data (step 56). A non-limiting example is data representing a voltage of the analog output. The data is collected (e.g., recorded) by the data collection module 18 (step 58). Data quality is measured (step 60) by the data quality measurement module 20, and it is determined (step 62) whether the data quality is below a predetermined value. Example methods for determining data quality are described above. In a particular example method, the data quality measurement module 20 compares data from the data collection module 18 (or as otherwise produced by the transducers 14) over an execution time (e.g., 30 seconds, but this can be greater or smaller) to an upper and lower threshold established such that data within the predetermined range is representative of transducers that are blocked, such as by ice formed on the transducers. The range or threshold of output signals representative of blocked transducers can be predetermined by the training step (step 50), either in the field or in another environment, such as a laboratory. If the data quality measurement module 20 determines that the data quality is low, suggesting icing on the transducers 14, the activation switch 38 activates the heater 36 to heat the transducers (step 64). In a particular example method, the activation switch 38 switches the relay linked to the power supply (e.g., a 24V power supply) to provide current to the heater 36. For example, low quality data can set a flag that results in the activation switch 38, and this activation triggers the relay. The status recording module 42 records an "ON" status for the heater 36 in the recorded data from the data collection module 18 (step 66), so that such data can later be adjusted or removed. The process then reverts to step 56 for collection of additional data. If, on the other hand, the data quality measurement module 20 determines that the data quality is not low, i.e., that the data quality meets or exceeds the predetermined value, and thus suggesting that the transducers 14 are unblocked, the deactivation switch 40 de-activates the heater 36 to stop (or significantly lower) heating to the transducers (step 68). In a particular example method, the deactivation switch 40 switches off the relay linked to the power supply (e.g., a 24V power supply) to cut off current to the heater 36. For example, the acceptable data quality can deactivate a flag of switch 40 indicating deactivation of the heating, and this flag triggers switching off the relay. The status recording module 42 records an "OFF" status (or removes "ON" status) for the heater 36 in the recorded data from the data collection module 18 (step 70), so that such data can later be adjusted or removed. "ON" and "OFF" may be replaced by one and zero, by flag = true or flag = false, or by other suitable identifiers. The process then reverts to step 56 for collection of additional data.

By selectively and automatically heating scientific instruments such as the sonic anemometer 12 in response to data quality, the example apparatus 10 can require less power for heating, while still being capable of unmanned operation. Further, as opposed to some conventional methods where heating is activated merely by absolute temperature, the example apparatus 10 is configured to respond to actual blockage of the scientific instruments, e.g., of the transducers 14, which results in less heating operation, saving power and limiting bias of measurements caused by heating. The apparatus 10 is particularly suitable for operating in remote environments in which icing occurs, but can be used for any environment where icing or other blockage removable by heating can occur. By indicating when the scientific equipment is being heated, and thus when resulting data may be biased, the apparatus 10 can also improve analysis of measurement data from the scientific equipment.

In an example operation, a sonic anemometer embodied in a METEK uSonic-3 Class A ultrasonic anemometer and a gas analyzer, e.g., a closed-path LI-7200 (LI-CO Biosciences, Lincoln, NE, USA), were placed at a remote location. The sonic anemometer and gas analyzer were coupled to a suitable power source. The sonic anemometer was coupled to a datalogger embodied in a Campbell CR3000 Micrologger. A switch port of the datalogger was connected to a relay linked to a 24V power supply, which powered heating for the sonic anemometer. For a remotely located automatically heating sonic anemometer, an example power source is embodied in a diesel generator, solar panels, and a wind turbine, or a combination. To provide a low-power heating strategy for the sonic anemometer, the datalogger included programmed instructions to activate the power supply when a quality flag indicated low data quality, so that the sonic anemometer was sporadically heated, i.e., activated only when blockage, e.g., ice blockage, was detected in the sonic anemometer's data stream:

'Temperature control system using the Ux data analogue output VoltDiff (METEK U, 1 ,mV5000,3,True ,0,250, 1.0,0)

'temperature control

If METEK_U>-10 AND METEK I 10 Then SW12 (2,1)

METEK_HEATING= 1

Else

SW12 (2,0)

METEK_HEATING=0

Endlf

To monitor the impact of the anemometer heating on the temperature of the anemometer itself, four thermocouples were attached to the lower and upper spars and bars of the anemometer.

The resulting sonic anemometer data was compared to data coverage obtained at another remote location using anemometers for which heating was deactivated, and then turned on continuously. FIG. 3 shows example temperature controls installed on the sporadically heated sonic anemometer (Chart B) for a period between August 26 and October 31 in comparison to air temperature for anemometers for which heating was deactivated between July 25 and August 9 (Heating OFF), and then continuously activated (Heating continuously ON) on August 15 (Chart A). To monitor the impact of anemometer heating on the temperature of the deactivated/continuously activated anemometers, three thermocouples were attached to the sonic anemometer (upper spar: red lines; lower bar: blue line; air temperature; black line). For the sporadically heated sonic anemometer, a quality flag (QF = 0: heating OFF; QF ≠ 0; heating ON) was used to record when the heating was activated (green line, right axis). Thermocouples were attached in corresponding locations for the sporadically heated anemometer (upper spar: red lines; lower bar: blue line; air temperature; black line).

To perform the cross-comparisons, all instruments were individually calibrated and compared to reference sensors: e.g., the sonic temperature was cross-compared to the air temperature measured with an HMP45C probe (Vaisala Inc., Helsinki, Finland) over 30 min time steps; sonic wind speed and orientation were compared to a cup anemometer set on the same tower at a maximum vertical separation of 50 cm.

The automatic heating apparatus successfully de-iced the transducers of the sonic anemometer with minimal hours of activation, successfully reducing power consumption. Data recorded during the heating activations, as indicated by the automatic heating apparatus, can be discarded.

Those of ordinary skill in the art will appreciate that information and signals may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

Those of ordinary skill in the art would further appreciate that the various illustrative logical blocks, modules, circuits, and process steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in various ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

The various illustrative logical blocks, modules, and circuits described in connection with the embodiments disclosed herein may be implemented or performed with a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

The steps of a method or process described in connection with the embodiments discloses herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, solid state disk, optical media (e.g., CD-ROM), or any other form of transitory or non-transitory storage medium known in the art. An exemplary storage medium can be coupled to the processor such that the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium can be integral to the processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a user terminal. In the alternative, the processor and the storage medium may reside as discrete components in a user terminal.

While various embodiments of the present invention have been shown and described, it should be understood that other modifications, substitutions, and alternatives are apparent to one of ordinary skill in the art. Such modifications, substitutions, and alternatives can be made without departing from the spirit and scope of the invention, which should be determined from the appended claims.

Various features of the invention are set forth in the appended claims.