Patent Description:
Vibratory meters, such as for example, Coriolis mass flowmeters, liquid density meters, gas density meters, liquid viscosity meters, gas/liquid specific gravity meters, gas/liquid relative density meters, and gas molecular weight meters, are generally known and are used for measuring characteristics of fluids. Generally, vibratory meters comprise a sensor assembly and a meter electronics. The material within the sensor assembly may be flowing or stationary. The vibratory meter may be used to measure a mass flow rate, density, or other properties of a material in the sensor assembly.

The vibratory meter may be oriented in different directions. For example, where the sensor assembly has two bent conduits containing the material, the bent conduits may have a tubes-up, tubes-down, or flag orientation. Additionally, the vibratory meter may be calibrated in an orientation and installed at a customer site in a different orientation. For example, the vibratory meter may be calibrated in a tubes-up orientation and installed in a customer site in a flag orientation.

However, due to the density of the material varying due to pressure (i.e., head pressure can cause density of the material to increase) and other effects on the vibration characteristics of vibratory meters (e.g., rotational elements of mode shapes) caused by the relative direction of gravitational forces, the orientation of the sensor assembly may affect a measurement of the vibratory meter. For example, a density measurement by a sensor assembly in a tubes-down orientation may be greater than a density measurement by the same sensor assembly in a tubes-up orientation. Accordingly, there is a need to detect the orientation of the vibratory meter and compensate the measurement of the vibratory meter based on the detected orientation.

<CIT> Al discloses a meter electronics and a measuring device comprising a measuring tube in accordance with the prior art, wherein a dependence of the signal parameters on the inclination of a measuring tube is taken into account by means of an inclinometer.

A meter electronics for detecting an orientation and compensating a measurement based on the detected orientation is provided. According to an embodiment, the meter electronics comprises an interface configured to communicatively couple to a sensor assembly and a processing system. The processing system is configured to detect an orientation of the sensor assembly based on one or more vibration modes as observed in one or more sensor signals provided by the sensor assembly.

A vibratory meter for detecting an orientation and compensating a measurement based on the detected orientation is provided. According to an embodiment, the vibratory meter comprises a sensor assembly and a meter electronics communicatively coupled to the sensor assembly. The meter electronics is configured to detect an orientation of the sensor assembly based on one or more vibration modes as observed one or more sensor signals provided by the sensor assembly.

A method for detecting an orientation of a vibratory meter and compensating a measurement based on the detected orientation is provided. According to an embodiment the method comprises receiving one or more sensor signals from a sensor assembly and detecting an orientation of the sensor assembly based one or more vibration modes as observed in the one or more sensor signals provided by the sensor assembly.

According to an aspect, a meter electronics (<NUM>) for detecting an orientation and compensating a measurement based on the detected orientation comprises an interface (<NUM>) configured to communicatively couple to a sensor assembly (<NUM>), and a processing system (<NUM>) configured to detect an orientation of the sensor assembly (<NUM>) based on one or more vibration modes as observed in one or more sensor signals provided by the sensor assembly (<NUM>).

Preferably, the processing system (<NUM>) being configured to detect the orientation of the sensor assembly (<NUM>) based on the one or more sensor signals comprises the processing system (<NUM>) being configured to detect the orientation based on a time-period of one or more vibration modes of the sensor assembly (<NUM>) as observed in a sensor signal in the one or more sensor signals provided by the sensor assembly (<NUM>).

Preferably, the meter electronics (<NUM>) being configured to detect the orientation based on the time-period of one or more vibration modes comprises the meter electronics (<NUM>) being configured to detect the orientation based on density values determined from at least two of the one or more vibration modes.

Preferably, the processing system (<NUM>) is further configured to compensate a measurement based on the detected orientation of the sensor assembly (<NUM>).

Preferably, the processing system (<NUM>) being further configured to compensate the measurement based on the detected orientation of the sensor assembly (<NUM>) comprises the processing system (<NUM>) being further configured to compensate the measurement based on a relationship of the detected orientation of the sensor assembly (<NUM>) to a reference orientation of the sensor assembly (<NUM>).

Preferably, the reference orientation is a calibration orientation.

Preferably, the detected orientation of the sensor assembly (<NUM>) is one of a tubes-down orientation (500A), a tubes-up orientation (500B), and a flag orientation (500C).

According to an aspect, a vibratory meter (<NUM>) for detecting an orientation and compensating a measurement based on the detected orientation comprises a sensor assembly (<NUM>), and a meter electronics (<NUM>) communicatively coupled to the sensor assembly (<NUM>). The meter electronics (<NUM>) is configured to detect an orientation of the sensor assembly (<NUM>) based on one or more vibration modes as observed in one or more sensor signals provided by the sensor assembly (<NUM>).

Preferably, the meter electronics (<NUM>) being configured to detect the orientation of the sensor assembly (<NUM>) based on the one or more sensor signals comprises the meter electronics (<NUM>) being configured to detect the orientation based on a time-period of one or more vibration modes of the sensor assembly (<NUM>) as observed in a sensor signal in the one or more sensor signals provided by the sensor assembly (<NUM>).

Preferably, meter electronics (<NUM>) is further configured to compensate a measurement based on the detected orientation of the sensor assembly (<NUM>).

Preferably, the meter electronics (<NUM>) being further configured to compensate the measurement based on the detected orientation of the sensor assembly (<NUM>) comprises the meter electronics (<NUM>) being further configured to compensate the measurement based on a relationship of the detected orientation of the sensor assembly (<NUM>) to a reference orientation of the sensor assembly (<NUM>).

According to an aspect, a method for detecting an orientation of a vibratory meter and compensating a measurement based on the detected orientation comprises receiving one or more sensor signals from a sensor assembly, and detecting an orientation of the sensor assembly based on the one or more sensor signals provided by the sensor assembly.

Preferably, detecting the orientation of the sensor assembly based on the one or more sensor signals comprises detecting the orientation based on a time-period of one or more vibration modes of a sensor assembly as observed in a sensor signal in the one or more sensor signals provided by the sensor assembly.

Preferably, detecting the orientation based on the time-period of one or more vibration modes comprises detecting the orientation based on density values determined from at least two of the one or more vibration modes.

Preferably, the method further comprises compensating a measurement based on the detected orientation of the sensor assembly.

Preferably, compensating the measurement based on the detected orientation of the sensor assembly comprises compensating the measurement based on a relationship of the detected orientation of the sensor assembly to a reference orientation of the sensor assembly.

Preferably, the detected orientation of the sensor assembly is one of a tubes-down orientation, a tubes-up orientation, and a flag orientation.

<FIG> and the following description depict specific examples to teach those skilled in the art how to make and use the best mode of embodiments of detecting an orientation and correcting a measurement based on the detected orientation. For the purpose of teaching inventive principles, some conventional aspects have been simplified or omitted. Those skilled in the art will appreciate variations from these examples that fall within the scope of the present description. Those skilled in the art will appreciate that the features described below can be combined in various ways to form multiple variations of detecting an orientation and correcting a measurement based on the orientation. As a result, the embodiments described below are not limited to the specific examples described below, but only by the claims and their equivalents.

<FIG> shows a vibratory meter <NUM> for detecting an orientation and compensating a measurement based on the detected orientation. As shown in <FIG>, the vibratory meter <NUM> comprises a sensor assembly <NUM> and meter electronics <NUM>. The sensor assembly <NUM> responds to mass flow rate and density of a process material. The meter electronics <NUM> is connected to the sensor assembly <NUM> via leads <NUM> to provide density, mass flow rate, and temperature information over port <NUM>, as well as other information.

The sensor assembly <NUM> includes a pair of manifolds <NUM> and <NUM>', flanges <NUM> and <NUM>' having flange necks <NUM> and <NUM>', a pair of parallel conduits <NUM> and <NUM>', driver <NUM>, resistive temperature detector (RTD) <NUM>, and a pair of pick-off sensors <NUM> and 170r. Conduits <NUM> and <NUM>' have two essentially straight inlet legs <NUM>, <NUM>' and outlet legs <NUM>, <NUM>', which converge towards each other at conduit mounting blocks <NUM> and <NUM>'. The conduits <NUM>, <NUM>' bend at two symmetrical locations along their length and are essentially parallel throughout their length. Brace bars <NUM> and <NUM>' serve to define the axis W and W' about which each conduit <NUM>, <NUM>' oscillates. The legs <NUM>, <NUM>' and <NUM>, <NUM>' of the conduits <NUM>, <NUM>' are fixedly attached to conduit mounting blocks <NUM> and <NUM>' and these blocks, in turn, are fixedly attached to manifolds <NUM> and <NUM>'. This provides a continuous closed material path through sensor assembly <NUM>.

When flanges <NUM> and <NUM>', having holes <NUM> and <NUM>' are connected, via inlet end <NUM> and outlet end <NUM>' into a process line (not shown) which carries the process material that is being measured, material enters inlet end <NUM> of the meter through an orifice <NUM> in the flange <NUM> and is conducted through the manifold <NUM> to the conduit mounting block <NUM> having a surface <NUM>. Within the manifold <NUM> the material is divided and routed through the conduits <NUM>, <NUM>'. Upon exiting the conduits <NUM>, <NUM>', the process material is recombined in a single stream within the block <NUM>' having a surface <NUM>' and the manifold <NUM>' and is thereafter routed to outlet end <NUM>' connected by the flange <NUM>' having holes <NUM>' to the process line (not shown).

The conduits <NUM>, <NUM>' are selected and appropriately mounted to the conduit mounting blocks <NUM>, <NUM>' so as to have substantially the same mass distribution, moments of inertia and Young's modulus about bending axes W--W and W'--W', respectively. These bending axes go through the brace bars <NUM>, <NUM>'. Inasmuch as the Young's modulus of the conduits change with temperature, and this change affects the calculation of flow and density, RTD <NUM> is mounted to conduit <NUM>' to continuously measure the temperature of the conduit <NUM>'. The temperature of the conduit <NUM>' and hence the voltage appearing across the RTD <NUM> for a given current passing therethrough is governed by the temperature of the material passing through the conduit <NUM>'. The temperature dependent voltage appearing across the RTD <NUM> is used in a well-known method by the meter electronics <NUM> to compensate for the change in elastic modulus of the conduits <NUM>, <NUM>' due to any changes in conduit temperature. The RTD <NUM> is connected to the meter electronics <NUM> by lead <NUM>.

Both of the conduits <NUM>, <NUM>' are driven by driver <NUM> in opposite directions about their respective bending axes W and W' and at what is termed the first out-of-phase bending mode of the flow meter. This driver <NUM> may comprise any one of many well-known arrangements, such as a magnet mounted to the conduit <NUM>' and an opposing coil mounted to the conduit <NUM> and through which an alternating current is passed for vibrating both conduits <NUM>, <NUM>'. A suitable drive signal <NUM> is applied by the meter electronics <NUM>, via a lead, to the driver <NUM>.

The meter electronics <NUM> receives the RTD temperature signal on lead <NUM>, and sensor signals <NUM> appearing on leads <NUM> carrying left and right sensor signals <NUM>, 165r, respectively. The meter electronics <NUM> produces the drive signal <NUM> appearing on the lead to driver <NUM> and vibrate conduits <NUM>, <NUM>'. The meter electronics <NUM> processes the left and right sensor signals <NUM>, 165r and the RTD signal <NUM> to compute the mass flow rate and the density of the material passing through sensor assembly <NUM>. This information, along with other information, is applied by meter electronics <NUM> over path <NUM> as a signal. A more detailed discussion of the meter electronics <NUM> follows.

<FIG> shows a block diagram of the vibratory meter <NUM>, including a block diagram representation of the meter electronics <NUM>. As shown in <FIG>, the meter electronics <NUM> is communicatively coupled to the sensor assembly <NUM>. As described in the foregoing with reference to <FIG>, the sensor assembly <NUM> includes the left and right pick-off sensors <NUM>, 170r, driver <NUM>, and temperature sensor <NUM>, which are communicatively coupled to the meter electronics <NUM> via the set of leads <NUM> through a communications channel <NUM>.

The meter electronics <NUM> provides a drive signal <NUM> via the leads <NUM>. More specifically, the meter electronics <NUM> provides a drive signal <NUM> to the driver <NUM> in the sensor assembly <NUM>. In addition, sensor signals <NUM> comprising the left sensor signal <NUM> and the right sensor signal 165r are provided by the sensor assembly <NUM>. More specifically, in the embodiment shown, the sensor signals <NUM> are provided by the left and right pick-off sensor <NUM>, 170r in the sensor assembly <NUM>. As can be appreciated, the sensor signals <NUM> are respectively provided to the meter electronics <NUM> through the communications channel <NUM>.

The meter electronics <NUM> includes a processor <NUM> communicatively coupled to one or more signal processors <NUM> and one or more memories <NUM>. The processor <NUM> is also communicatively coupled to a user interface <NUM>. The processor <NUM> is communicatively coupled with the host via a communication port over the port <NUM> and receives electrical power via an electrical power port <NUM>. The processor <NUM> may be a microprocessor although any suitable processor may be employed. For example, the processor <NUM> may be comprised of sub-processors, such as a multi-core processor, serial communication ports, peripheral interfaces (e.g., serial peripheral interface), on-chip memory, I/O ports, and/or the like. In these and other embodiments, the processor <NUM> is configured to perform operations on received and processed signals, such as digitized signals.

The processor <NUM> may receive digitized sensor signals from the one or more signal processors <NUM>. The processor <NUM> is also configured to provide information, such as a phase difference, a property of a fluid in the sensor assembly <NUM>, or the like. The processor <NUM> may provide the information to the host through the communication port. The processor <NUM> may also be configured to communicate with the one or more memories <NUM> to receive and/or store information in the one or more memories <NUM>. For example, the processor <NUM> may receive calibration factors and/or sensor assembly zeros (e.g., phase difference when there is zero flow) from the one or more memories <NUM>. Each of the calibration factors and/or sensor assembly zeros may respectively be associated with the flow meter <NUM> and/or the sensor assembly <NUM>. The processor <NUM> may use the calibration factors to process digitized sensor signals received from the one or more signal processors <NUM>.

The one or more signal processors <NUM> is shown as being comprised of an encoder/decoder (CODEC) <NUM> and an analog-to-digital converter (ADC) <NUM>. The one or more signal processors <NUM> may condition analog signals, digitize the conditioned analog signals, and/or provide the digitized signals. The CODEC <NUM> is configured to receive the sensor signals <NUM> from the left and right pick-off sensors <NUM>, 170r. The CODEC <NUM> is also configured to provide the drive signal <NUM> to the driver <NUM>. In alternative embodiments, more or fewer signal processors may be employed.

As shown, the sensor signals <NUM> are provided to the CODEC <NUM> via a signal conditioner <NUM>. The drive signal <NUM> is provided to the driver <NUM> via the signal conditioner <NUM>. Although the signal conditioner <NUM> is shown as a single block, the signal conditioner <NUM> may be comprised of signal conditioning components, such as two or more op-amps, filters, such as low pass filters, voltage-to-current amplifiers, or the like. For example, the sensor signals <NUM> may be amplified by a first amplifier and the drive signal <NUM> may be amplified by the voltage-to-current amplifier. The amplification can ensure that the magnitude of the sensor signals <NUM> is approximate the full-scale range of the CODEC <NUM>.

In the embodiment shown, the one or more memories <NUM> is comprised of a read-only memory (ROM) <NUM>, random access memory (RAM) <NUM>, and a ferroelectric random-access memory (FRAM) <NUM>. However, in alternative embodiments, the one or more memories <NUM> may be comprised of more or fewer memories. Additionally, or alternatively, the one or more memories <NUM> may be comprised of different types of memory (e.g., volatile, non-volatile, etc.). For example, a different type of non-volatile memory, such as, for example, erasable programmable read only memory (EPROM), or the like, may be employed instead of the FRAM <NUM>. The one or more memories <NUM> may be a storage configured to store process data, such as drive or sensor signals, mass flow rate or density measurements, etc..

A mass flow rate measurement (ṁ) can be generated according to the equation: <MAT> The Δt term comprises an operationally-derived (i.e., measured) time delay value comprising the time delay existing between the pickoff sensor signals, such as where the time delay is due to Coriolis effects related to mass flow rate through the vibratory flowmeter <NUM>. The measured Δt term ultimately determines the mass flow rate of the flow material as it flows through the vibratory flowmeter <NUM>. The Δt<NUM> term comprises a time delay/phase difference at zero flow calibration constant. The Δt<NUM> term is typically determined at the factory and programmed into the vibratory flowmeter <NUM>. The time delay/phase difference at zero flow Δt<NUM> term will not change, even where flow conditions are changing. A mass flow rate of flow material flowing through the flow meter is determined by multiplying a measured time delay (or phase difference/frequency) by the flow calibration factor FCF. The flow calibration factor FCF is proportional to a physical stiffness of the flow meter.

As to density, a resonance frequency at which each conduit <NUM>, <NUM>' will vibrate may be a function of the square root of a spring constant of the conduit <NUM>, <NUM>' divided by the total mass of the conduit <NUM>, <NUM>' having a material. The total mass of the conduit <NUM>, <NUM>' having the material may be a mass of the conduit <NUM>, <NUM>' plus a mass of a material inside the conduit <NUM>, <NUM>'. The mass of the material in the conduit <NUM>, <NUM>' is directly proportional to the density of the material. Therefore, the density of this material may be proportional to the square of a period at which the conduit <NUM>, <NUM>' containing the material oscillates multiplied by the spring constant of the conduit <NUM>, <NUM>'. Hence, by determining the period at which the conduit <NUM>, <NUM>' oscillates and by appropriately scaling the result, an accurate measure of the density of the material contained by the conduit <NUM>, <NUM>' can be obtained. The meter electronics <NUM> can determine the period or resonance frequency using the sensor signals <NUM> and/or the drive signal <NUM>. The conduits <NUM>, <NUM>' may oscillate with more than one vibration mode.

<FIG> show wireline diagrams of conduits to illustrate vibration modes of the conduits, such as the conduits <NUM>, <NUM>' described above. As shown in <FIG>, the conduits are depicted by wirelines <NUM>. The wirelines <NUM> have a U-shape to reflect U-shaped conduits, which may be comprised of a left conduit and a right conduit. As shown in <FIG>, the wirelines <NUM> include a left at-rest wireline 312a and a right at-rest wireline 312b. Also shown in <FIG> are bend axes W-W, W'-W', which is collocated with a vibration node of the wirelines <NUM>. In <FIG>, the wirelines <NUM> also include a left first order bend mode wireline 314a and a right first order bend mode wireline 314b. Also shown are a left second order bend mode wireline 316a and a right second order bend mode wireline 316b. In <FIG>, the wirelines <NUM> include a left first order twist mode 318a and a right first order twist mode 318b.

The left and right first order bend mode wirelines 314a, 314b are shown by arrows to be <NUM> degrees out of phase. That is, they move in an opposing manner. This may be beneficial in various ways, such as reducing a vibration of a vibratory meter due to an unbalanced displacement of the conduits. The left and right first order bend mode wirelines 314a, 314b are also shown as having a single node, which is collocated with the bend axes W-W, W-W'. The left and right second order bend mode wirelines 316a, 316b are also shown by arrows to be <NUM> degrees out of phase with each other. However, the left and right second order bend mode wirelines 316a, 316b have two vibration nodes, hence the term "second order. " A natural frequency of the left and right second order bend mode wirelines 316a, 316b may be higher than a natural frequency the left and right first order bend mode wirelines 314a, 314b. The left first order twist mode 318a and the right first order twist mode 318b are shown as having asymmetric displacement relative to the left and right at-rest wirelines 312a, 312b along their respective lengths. Arrows illustrate that the left and right first order twist modes 318a, 318b are out of phase with each other.

The vibration modes illustrated by the wirelines <NUM> are shown as being separate but may be superimposed onto the conduits modeled by the wirelines <NUM>. That is, the conduits modeled by the wirelines <NUM> may have multiple vibration modes. For example, a left conduit of the conduits may have a first order bend mode, a second order bend mode, and a twist mode. Accordingly, the conduits may have a first order out of phase bend mode, a second order out of phase bend mode, and a first order twist mode. The conduits may have additional modes, such as higher order bend modes (e.g., third, fourth, fifth, etc.), in-phase bend modes, and higher order twist modes (e.g., second, third, fourth, etc.).

As the foregoing illustrates, a vibration mode may have a shape, amplitude, and natural frequency. The shape of the vibration modes can be detected by comparing the sensor signals, such as the sensor signals <NUM>, to each other. A phase difference between a sensor signal provided by the left pick-off sensor <NUM> and a sensor signal provided by the right pick-off sensor signal 170r may indicate a twist mode excitation caused by Coriolis forces due to flow through the vibratory meter as the tubes vibrate in a bending or other mode, and may be proportional to the phase difference between the conduits <NUM>, <NUM>'. The amplitude of the vibration modes may be proportional to an amplitude of the sensor signals <NUM>.

The frequencies of the vibration modes may be determined from the sensor signals <NUM> and/or the drive signal <NUM>. More specifically, due to each vibration mode having a natural mode frequency, the sensor signals <NUM> may have components that correspond to the vibration modes of the conduits <NUM>, <NUM>'. Accordingly, filtering may be used to isolate the components to determine a frequency of each component. The frequency of each component corresponds to frequency of a vibration mode. The frequencies of the vibration modes may be referred to individually as a mode frequency. That is, the mode frequency is a natural frequency of a vibration mode, each of which corresponds to a component in the sensor signals <NUM> and/or the drive signal <NUM>.

The vibration modes may have relationships. For example, a relationship between two vibration modes, herein referred to as a mode relationship, may be based on the phase, amplitude, and frequency of the two vibration modes. In one example, a mode relationship may be a difference in a frequency of the left and right second order bend mode wirelines 316a, 316b and a frequency of the left and right first order bend mode wirelines 314a, 314b. The mode relationship may be quantified as mode difference. For example, the mode relationship may be a difference between a time-period of the left and right second order bend mode wirelines 316a, 316b relative to a time-period of the left and right first order bend mode wirelines 314a, 314b.

<FIG> shows the meter electronics <NUM> for detecting an orientation of a vibratory meter and compensating a measurement based on the detected orientation. As shown in <FIG>, the meter electronics <NUM> includes an interface <NUM> and a processing system <NUM>. The meter electronics <NUM> receives a vibrational response, such as from the sensor assembly <NUM>, for example. The meter electronics <NUM> processes the vibrational response in order to obtain flow characteristics of the flow material flowing through the sensor assembly <NUM>.

The interface <NUM> may receive the sensor signals <NUM> from one of the pick-off sensors <NUM>, 170r shown in <FIG> and <FIG>. The interface <NUM> can perform any necessary or desired signal conditioning, such as any manner of formatting, amplification, buffering, etc. Alternatively, some or all of the signal conditioning can be performed in the processing system <NUM>. In addition, the interface <NUM> can enable communications between the meter electronics <NUM> and external devices. The interface <NUM> can be capable of any manner of electronic, optical, or wireless communication. The interface <NUM> can provide information based on the vibrational response. The interface <NUM> may be coupled with a digitizer, such as the CODEC <NUM> shown in <FIG>, wherein the sensor signal comprises an analog sensor signal. The digitizer samples and digitizes an analog sensor signal and produces a digitized sensor signal.

The processing system <NUM> conducts operations of the meter electronics <NUM> and processes flow measurements from the sensor assembly <NUM>. The processing system <NUM> executes one or more processing routines and thereby processes the flow measurements in order to produce one or more flow characteristics. The processing system <NUM> is communicatively coupled to the interface <NUM> and is configured to receive the information from the interface <NUM>.

The processing system <NUM> can comprise a general-purpose computer, a micro-processing system, a logic circuit, or some other general purpose or customized processing device. Additionally, or alternatively, the processing system <NUM> can be distributed among multiple processing devices. The processing system <NUM> can also include any manner of integral or independent electronic storage medium, such as the storage system <NUM>.

The storage system <NUM> can store flow meter parameters and data, software routines, constant values, and variable values. In one embodiment, the storage system <NUM> includes routines that are executed by the processing system <NUM>, such as the operational routine <NUM> and compensation routine <NUM> of the vibratory meter <NUM>. The storage system can also store statistical values, such as a standard deviation, confidence intervals, or the like.

The compensation routine <NUM> may compensate a measurement, such as a mass flow rate measurement, for an orientation of a vibratory meter. For example, as will be described in more detail in the following, the compensation routine <NUM> may detect an orientation of a sensor assembly of the vibratory meter, such as the sensor assembly <NUM> described above, based on one or more sensor signals provided by the sensor assembly <NUM>. The compensation routine <NUM> may compensate a measurement, such as a mass flow rate measurement, based on a relationship of the detected orientation of the sensor assembly to a reference orientation of the sensor assembly. The reference orientation may be a calibration orientation.

Accordingly, the storage system <NUM> may also store calibration information <NUM>. As shown in <FIG>, the calibration information <NUM> includes a calibration orientation <NUM> and calibration signals <NUM>. The calibration orientation <NUM> may be a value of a list of orientations, such as a tubes-up orientation, a tubes-down orientation, or a flag orientation. The calibration orientation <NUM> may be detected from the calibration signals <NUM>, input by a user, automatically detected by an accelerometer, or the like. The calibration orientation <NUM> is associated with the calibration signals <NUM>.

The calibration signals <NUM> may be measured and stored during a calibration of the vibratory meter <NUM>. The calibration signals <NUM> may be a time-domain sampling of the sensor signals <NUM>, a frequency spectrum signal showing frequencies of vibration modes, a list of component frequencies where each component frequency is associated with a vibration mode frequency, a list of relationships between the components, any suitable combination of the foregoing, or the like. The calibration signals <NUM> are associated with the calibration orientation <NUM>.

The storage system <NUM> can also store operational information <NUM> that can include data related to an installation of the vibratory meter <NUM>. As shown in <FIG>, the operational information <NUM> includes a detected orientation <NUM>, operational signals <NUM>, an uncorrected measurement <NUM>, and a corrected measurement <NUM>. The detected orientation <NUM> may be a value taken from or pointing to a list of orientations, such as the tubes-up orientation, the tubes-down orientation, or the flag orientation. The detected orientation <NUM> may be detected from the operational signals <NUM>, input by a user, automatically detected by an accelerometer, or the like. The detected orientation <NUM> may be an installation orientation. The detected orientation <NUM> is associated with the operational signals <NUM>.

The operational signals <NUM> may be measured and stored during a calibration of the vibratory meter <NUM>. The operational signals <NUM> may be a time-domain sampling of the sensor signals <NUM> and/or drive signal <NUM>, a frequency spectrum signal showing frequencies of vibration modes, a list of component frequencies where each component frequency is associated with a vibration mode frequency, a list of relationships between the components, any suitable combination of the foregoing, or the like. The operational signals <NUM> may be associated with the detected orientation <NUM>.

The uncorrected measurement <NUM> and the corrected measurement <NUM> may be values of a parameter of a material that is measured by the vibratory meter <NUM>. The parameter may be any suitable parameter, such as density, mass flow rate, or any derived values, such as percentage void fraction, mixture or mixture component densities, etc. The uncorrected measurement <NUM> may not be corrected for the detected orientation of the vibratory meter <NUM>. For example, if the calibration orientation <NUM> is the tubes-up orientation and the detected orientation is the tubes-down orientation then a value of the uncorrected measurement <NUM> may not be equal to a measurement of the vibratory meter <NUM> in the tubes-up orientation. However, as will be explained in more detail in the following, the uncorrected measurement <NUM> may be corrected into the corrected measurement <NUM> by using corrected measurement <NUM> so as to be equal to the measurement by the vibratory meter <NUM> in the tubes-up orientation.

The storage system <NUM> may also store reference information <NUM> that can include reference related data that can be used to determine an orientation of the vibratory sensor <NUM>. As shown in <FIG>, the reference information <NUM> includes reference signals <NUM> and orientation correlations <NUM>. The reference signals <NUM> may be sensor signals associated with known orientations. For example, the reference signals <NUM> may be a list of component frequencies, each of which is associated with a given vibration mode, that is associated with an orientation. This list may be used to determine an orientation signature, such as one of the orientation correlations <NUM> shown in <FIG>. The reference orientations <NUM> may be a list of orientations, for example, that may be used during a calibration that are associated with the reference signals <NUM>. Accordingly, the reference signals <NUM> may be the same as the calibration signals <NUM>.

The orientation correlations <NUM> may be a list of mode relationships that are associated with orientations of the vibratory meter <NUM>. For example, the orientation correlations <NUM> may be a list of mode relationships that are correlated with orientations of the sensor assembly <NUM>. The mode relationships may be quantitative relationships, such as differences and ratios, of two or more vibration parameter values respectively associated with modes, as is explained in the following with respect to <FIG>, which relies on tube periods and observed density values, although any suitable parameters may be employed.

Still referring to <FIG>, the storage system <NUM> may also include correction information <NUM>. The correction information <NUM> is shown as including correction values <NUM>, correction orientations <NUM>, and orientation relationships <NUM>. The correction values <NUM> may be associated with orientations of the vibratory meter <NUM>. For example, the correction values <NUM> may include a list of values each of which is associated with an orientation of the vibratory meter <NUM>, such as the correction orientations <NUM> shown in <FIG>. The correction orientations <NUM> may include a list of orientations, such as a tubes-up orientation, a tube-down orientation, or flag orientation, or the like.

As can be appreciated, the correction values <NUM> may be associated with the correction orientations <NUM> depending on relationships between orientations, such as a relationship between the calibration orientation <NUM> and the detected orientation <NUM>. These and other relationships may be in the orientation relationships <NUM>. For example, if the calibration orientation <NUM> is a tubes-up orientation and the detected orientation is a tubes-down orientation, then the orientation relationship may be tubes-up to tubes-down relationship. The orientation relationships <NUM> may relate the tubes-up to tube-down relationship to a correction value in the correction values <NUM>. Accordingly, the uncorrected measurement <NUM> may be corrected to the corrected measurement <NUM> using the correction value.

The orientation relationships <NUM> may also include relationships between two of the correction values <NUM> and the orientation relationships. For example, a first correction value in the correction values <NUM> may be associated with the tubes-up to tubes-down relationship and a second correction value may be associated with a tubes-down to tubes-up relationship. A difference between the first and second correction value may be associated with a tubes-down to flag relationship. That is, the calibration orientation <NUM> may be the tubes-down orientation and the detected orientation <NUM> may be the flag orientation. Accordingly, the uncorrected measurement <NUM> may be corrected to the corrected measurement <NUM> using the difference between the first and second correction value.

As can be appreciated, the calibration orientation <NUM> may always be in a particular orientation, such as the tubes-down orientation. Accordingly, the correction values <NUM> may only have three values that are each associated by the orientation relationship <NUM> with the tubes-up, tube-down, and flag orientations of the corrections orientations <NUM>. However, the orientation relationships <NUM> may also include relationships between correction values relationships, such as a relationship between two of the correction values, and an orientation relationship.

As can also be appreciated, the correction value associated with an indifferent orientation relationship (e.g., tubes-up to tubes-up, tubes-down to tubes-down, flag to flag relationships, etc., see <FIG>) may be null, zero, or the like. For example, if the uncorrected measurement <NUM> is corrected by adding the correction value, the correction value may be zero for the indifferent orientation relationship. If the uncorrected measurement <NUM> is corrected by multiplying the correction value, the correction value may be null to indicate that the multiplication operation should not be performed. Accordingly, the corrected measurement <NUM> may be the same as the uncorrected measurement <NUM>. The correction may need to be made based on a detected orientation of a vibratory meter, which means that the orientations may need to be defined, as is shown in the following with reference to <FIG>.

<FIG> show different exemplary orientations of the vibratory meter <NUM>. As shown in <FIG>, the vibratory meter <NUM> has a tubes-down orientation 500A and in <FIG> the vibratory meter <NUM> has a tube-up orientation 500B. The vibratory meter <NUM> is shown as having a flag orientation 500C in <FIG>. In <FIG>, the vibratory meter <NUM> includes a transverse axis <NUM> that may be defined as being transversal to a material flow direction. The vibratory meter <NUM> also includes a longitudinal axis <NUM>. The material flow direction may be viewed as collinear with the longitudinal axis at the flange <NUM> to flange <NUM>' even though the material may flow in other directions between the flanges <NUM>, <NUM>'.

Also shown in <FIG> are a tubes-down center-of-gravity 530a, a tubes-up center-of-gravity 530b, and a flag center-of-gravity 530c. A center-of-gravity for a vibratory meter may be a center of mass of the fluid and conduit material between the brackets, although any suitable center of mass may be employed. As shown in <FIG>, a tubes-down transversal length 532a corresponds to the tubes-down center-of-gravity 530a, a tubes-up transversal length 532b corresponds to the tubes-up center-of-gravity 530b, and a flag transversal length 532c corresponds to the flag center-of-gravity 530c. A flag longitudinal length 534c also corresponds to the flag center-of-gravity 530c. As can be appreciated from <FIG>, the location of the center-of-gravity relative to the location of the brackets differs depending on the orientation of the vibratory meter <NUM>. More specifically, head pressure can cause density of a material to be greater when the vibratory meter <NUM> is in the tubes-down orientation 500A relative to the tubes-up orientation 500B. This can cause a measurement of the material in the vibratory meter <NUM> to be inaccurate. Accordingly, by detecting an orientation of the vibratory meter, the measurement may be corrected.

As will be explained in more detail in the following, an orientation of a vibratory meter may be detected by measuring sensor signal parameters of two or more vibration modes. For example, time-periods of conduits in the vibratory meter may be measured for a first order bend mode and a second order bend mode. These two time periods may be used to respectively determine observed density values: a first order observed density value and a second order observed density value. A difference in between the first and second observed density value may be compared to previously determined correlations to orientations of the vibratory meters to detect the orientation of the vibratory meter. Other sensor signal parameters may be used.

<FIG> shows a frequency spectrum graph <NUM> of a vibratory meter. As shown in <FIG>, the frequency spectrum graph <NUM> includes a frequency axis <NUM> in units of hertz (Hz) and a magnitude axis <NUM> in decibels (dB). As can be seen, the frequency axis <NUM> ranges from <NUM> to <NUM> and the magnitude axis <NUM> ranges from -<NUM> to <NUM> dB, although any suitable units and numerical ranges may be employed. The frequency spectrum graph <NUM> also includes a spectrum plot <NUM>. The spectrum plot <NUM> is shown as having a first order drive peak <NUM> and a second order drive peak <NUM>. Also shown is a first order twist mode peak <NUM> and an in-phase bending mode peak <NUM>. The first order drive peak <NUM> is at about <NUM> and the second order drive peak <NUM> is at about <NUM>.

The spectrum plot <NUM> may be generated by sweeping from <NUM> to <NUM> and measuring the resulting vibration. By way of example, with reference to the vibratory meter <NUM> described above, the drive signal <NUM> may be a sinusoidal signal provided to the conduits <NUM>, <NUM>' over a frequency of <NUM> to <NUM> at a fixed amplitude. An amplitude of the left and right sensor signals <NUM>, 165r may be measured as the drive signal <NUM> is swept from <NUM> to <NUM>. As can be appreciated, the first order drive peak <NUM> is centered about a natural frequency of the vibratory meter <NUM>. However, as can be seen in the spectrum plot <NUM>, both the first and second order drive peak <NUM>, <NUM> are above a noise floor of the spectrum plot <NUM> and may therefore be filtered and measured.

The first order drive peak <NUM> may correspond to a first order bend mode of the conduits <NUM>, <NUM>'. Similarly, the second order drive peak <NUM> may correspond to a second order bend mode of the conduits <NUM>, <NUM>'. Accordingly, during operation, the drive signal <NUM> may have two sinusoidal components that are respectively centered at about <NUM> and <NUM>. The sensor signals <NUM>, 165r may be filtered by two band pass filters respectively centered at about <NUM> and <NUM>. The CODEC <NUM> may track the first and second order drive peaks <NUM>, <NUM> as their frequencies vary due to material flow through the conduits <NUM>, <NUM>'.

Accordingly, sensor signal parameters of each vibration mode may be measured and may be correlated to the properties of the material in the conduits <NUM>, <NUM>'. For example, a time-period and a frequency of the drive signal <NUM> and/or sensor signals <NUM>, 165r may vary according to a density of the material in the conduits <NUM>, <NUM>'. Similarly, an amplitude of the drive signal <NUM> and/or sensor signals <NUM>, 165r may vary. As can be appreciated, other parameters of the material may be determined, such as, for example viscosity, flow rate, composition, or the like.

As can be appreciated, these sensor signal parameters may correspond to modes of vibration. For example, the first order bend mode corresponding to the first order drive peak <NUM> may have a frequency that is lower than a frequency of the second order bend mode corresponding to the second order drive peak <NUM>. Accordingly, the first order bend mode may be used to generate a first order density value and the second order bend mode may be used to generate a second order density value. As can be appreciated, these density values should be equal to each other, but may not be equal to each other due to an orientation of the vibratory meter. Accordingly, the difference in the density values, or other measured values or the sensor signal parameters, may be used to detect an orientation of the vibratory meter, as the following discussion illustrates.

<FIG> shows a calibration graph <NUM> illustrating a detection of an orientation of a vibratory meter. As shown in <FIG>, the calibration graph <NUM> includes a density axis <NUM> in units of grams-per-centimeter cubed (g/cm<NUM>) and a squared time-period axis <NUM> in units of micro-seconds squared (µs<NUM>). As indicated, the calibration graph <NUM> is of the vibratory meter in a tubes-down orientation. The calibration graph <NUM> includes a calibrated density value <NUM>. In other words, if an unknown material having a density value that is the same as the calibrated density value <NUM> is measured in the tube-down orientation (which is the same as the calibration orientation), then the observed density value will equal the calibrated density value <NUM>.

As can be seen, the calibration graph <NUM> includes a first order graph <NUM> and second order graph <NUM>. The first and second order graphs <NUM>, <NUM> were respectively obtained by measuring tube periods of first and second order bend modes during a calibration. More specifically, the first and second order graphs <NUM>, <NUM> were obtained by measuring the tube periods when the vibratory meter was alternatively filled with water and air. Air has a density of about <NUM>/cm<NUM> and water has a density of about <NUM>/cm<NUM>, which are respectively denoted as D1 and D2 in the calibration graph <NUM>.

As shown in <FIG>, the first order graph <NUM> includes a first order calibration plot <NUM> and the second order graph <NUM> includes a second order calibration plot <NUM>. The first and second order calibration plots <NUM>, <NUM> have respectively first order air coordinate 732a and a first order water coordinate 732b, and a second order air coordinate 742a and a second order water coordinate 742b. The first order air coordinate 732a and a second order air coordinate 742a are determined by measuring respectively the tube period of the first order bend mode and the second order bend mode, respectively, while air is in the conduits of the vibratory flow meter. Similarly, the first order water coordinate 732b and the second order water coordinate 742b are determined by measuring the tube period of the first order bend mode and the tube period of the second order bend mode, respectively, while water is in the conduits of the vibratory flow meter.

In most vibratory meters there is a linear relationship between a density of a material and a square of the tube period of the conduits containing the material. Accordingly, the first order air coordinate 732a and the first order water coordinate 732b are respectively comprised of a squared first order air tube period K1<NUM> and the air density value D1, and a squared first order water tube period K2<NUM> and the water density value D2. Similarly, the second order air coordinate 742a and a second order water coordinate 742b are comprised of a squared second order air tube period K3<NUM> and the air density value D1, and a squared second order water tube period K4<NUM> and the water density value D2. The linear relationship between the density of the material and the square of the tube period is relied on to generate the first and second order calibration plots <NUM>, <NUM> between their respective first order air coordinate 732a and first order water coordinate 732b, and second order air coordinate 742a and second order water coordinate 742b. For other vibratory meters, which exhibit a non-linear relationship, calibration plots can be defined as polynomial or other curve fits to two or more coordinates determined in a similar fashion at other densities with other fluid materials or fluid temperatures.

The first and second order calibration plots <NUM>, <NUM> may be used to determine a density of an unknown material. For example, where the vibratory meter is installed in a tubes-down orientation and the material has a density that is equal to the calibrated density value <NUM>, then the observed density value may equal the calibrated density value <NUM> determined from the first and second order calibration plots <NUM>, <NUM>. That is, first and second order calibration plots <NUM>, <NUM> will generate the same calibrated density value <NUM>. Associated with the calibrated density value <NUM> are a squared first order calibrated tube period 736a that is an ordinate on the first order calibration plot <NUM> and a squared second order calibrated tube period 746a that is an ordinate on the second order calibration plot <NUM>.

However, the vibratory meter may be installed in an orientation that is not the tube-down orientation used during calibration. When the vibratory meter is installed in an orientation that is not the same as the calibration orientation, the first and second order calibration plots <NUM>, <NUM> may not generate the calibrated density value <NUM>. In addition, the first and second order calibration plots <NUM>, <NUM> may respectively generate unequal first and second order density values <NUM>, <NUM>. This difference between the observed density values may be used to determine the orientation of the vibratory meter during measurement, as the following explains.

When the vibratory meter is installed in a flag orientation, the first and second order calibration plots <NUM>, <NUM> may respectively generate a first order flag density value 734b and a second order flag density value 744b that respectively correspond to a square first order flag tube period 736b and a square second order flag tube period 746b. When the vibratory meter is installed in a tubes-up orientation, the first and second order calibration plots <NUM>, <NUM> may respectively generate a first order tubes-up density value 734c and a second order tubes-up density value 744c that respectively correspond to a square first order tubes-up tube period 736c and a square second order tubes-up tube period 746c. As can be seen, the first and second order flag density values 734b, 744b are not equal to each other. Also, the first and second order tubes-up density values 734c, 744c are not equal to each other. The differences between the first and second order density values <NUM>, <NUM> are discussed in more detail in the following with reference to <FIG>.

<FIG> shows a detailed view of a portion of the calibration graph <NUM>. As shown in <FIG>, the density axis of the second order graph <NUM> is intersected by lines representing the first order flag density value 734b, the first order tubes-up density value 734c, the second order flag density value 744b, and the second order tubes-up density value 744c. A tubes-down density difference Δρdown is equal to zero, as is expected because the vibratory meter is calibrated in the tubes-down orientation. As can be appreciated, a flag density difference Δρflag is not equal to a tubes-up density difference Δρflag. As can also be appreciated, the tubes-up density difference Δρflag is about double the size of the flag density difference Δρflag. Accordingly, the orientation of the vibratory meter may be detected.

For example, the meter electronics <NUM> may store orientation correlations <NUM> that correlate the tubes-up density difference Δρup with a tubes-up orientation and the flag density difference Δρflag with the flag orientation. The correlations may be indexed by, for example, operating frequency, tube period, etc. That is, a value of the tubes-up density difference Δρup or the flag density difference Δρflag may differ in proportion to the operating frequency of the vibratory meter <NUM>. The orientation correlations <NUM> may be in any suitable form, such as percentages, ratios, or the like that are relative to or operate on other parameters, such the operating frequency of the vibratory meter <NUM>, observed density value, etc. Values other than density may be used in the orientation correlations <NUM>. For example, the orientation correlations <NUM> may correlate time periods, or squared time periods, or differences thereof, of the conduits <NUM> in the vibratory meter <NUM> with the orientations of the vibratory meter <NUM>. These and other correlations may be used to determine the orientation of a vibratory meter, such as the vibratory meter <NUM> described above, which may then be used to correct a measurement.

The correlations may be generalized to sensor signal parameters or other material parameters. For example, a time-period of a vibration may be denoted as tMO where "MO" denote the mode (m) and the order (O). The modes can be denoted by β and ζ respectively as bend and twist mode. The order may be denoted by <NUM>, <NUM>, <NUM>. So a first order bend mode and a first order twist mode can be respectively denoted as β1 and ζ1. A first order bend mode and a second order bend mode may be denoted as β1 and β2. Accordingly, a difference may be defined as tβ<NUM> - tβ<NUM>. This can be shortened to Δtβ<NUM>β<NUM>. This nomenclature may be used for material parameters, such as, for example, density. A density difference between densities determined using the first order bend mode and the second order bend mode may defined by ρβ<NUM> - ρβ<NUM>, which can be shortened to Δρβ1β2.

The below table illustrates how a measurement may be compensating based on an orientation of a vibratory meter. In the below table, the columns and rows are headed by the three orientations of tubes-down, tubes-up, and flag, although any suitable orientations and/or descriptions of the orientations may be employed. The table below also includes correction values designated by letters 'A' and 'B' that are in percentage of an uncorrected measurement. As shown, the correction values A, B are associated with a change from a calibration orientation to a current orientation. That is, A is a correction value (in % of reading) from tubes-down calibration to flag operation. B is a correction value (in % of reading) from tubes-down calibration to tubes-up operation.

The tubes-down calibration to a tubes-up operation may be a relationship between a reference orientation and a detected orientation of the vibratory meter. That is, the reference orientation may be the calibration orientation and the detected orientation may be the current orientation. Additionally, with reference to above <FIG>, the calibration orientation may be a value in the reference orientations <NUM>, the current orientation may be a value in the correction orientations <NUM>, and the relationship between the reference orientation and the detected orientation may be a value in the orientation relationships <NUM>.

Accordingly, when the current orientation is the same as the calibration orientation then the above table returns a null value indicating that the uncorrected measurement may not be corrected. Therefore, the uncorrected measurement may be provided as an accurate measurement. When the calibration orientation is tubes-down and the current orientation is tubes-up, then the correction value may be B. The uncorrected measurement may be corrected with B by, for example, adding the uncorrected measurement multiplied by B to the uncorrected measurement. As can also be seen in the above table, the tubes-up calibration orientation to flag orientation has a correction value of A-B. That is, the uncorrected measurement may be corrected by adding the uncorrected measurement multiplied by the difference of A and B to the uncorrected measurement.

<FIG> shows a method <NUM> of detecting an orientation of a vibratory meter. As shown in <FIG>, the method <NUM>, in step <NUM>, receives one or more sensor signals from a sensor assembly. The sensor assembly may be the same as the sensor assembly <NUM> described above, although any suitable sensor assembly may be employed. The one or more sensor signals may be received by, for example, the interface <NUM> described above. The interface <NUM> and/or processing system <NUM> may condition, sample, digitize, compress and/or expand, decimate, etc., the one or more received sensor signals. In step <NUM>, the method <NUM> detects an orientation of the sensor assembly based on the one or more sensor signals provided by the sensor assembly. The above described processing system <NUM> may detect the orientation.

The method <NUM>, in step <NUM>, may detect the orientation based on a time-period of one or more vibration modes of a sensor assembly as observed in a sensor signal in the one or more sensor signals provided by the sensor assembly. For example, the orientation may be detected based on the time-period of one or more vibration modes comprises detecting the orientation based on density values determined from at least two of the one or more vibration modes. In one example that is described above with reference to <FIG> and <FIG>, the method <NUM> may compare the first order flag density value 734b and the second order flag density value 744b to determine that the sensor assembly is in a flag orientation. This comparison may be a difference between the two density values or may be made relative to the calibrated density value <NUM>. For example, a difference between the first order flag density value 734b and the calibrated density value <NUM> may be compared to the difference between the second order flag density values 744b and the calibrated density value <NUM>. Other ways, such as comparing time periods, frequencies, or the like, may be employed to detect the orientation. Additionally, more than two vibration modes may be employed.

The method <NUM> may also compensate a measurement based on the detected orientation of the sensor assembly. For example, the measurement may be compensated based on a relationship of the detected orientation of the sensor assembly to a reference orientation of the sensor assembly. Referring to the example of the above table, the relationship of the detected orientation and the reference orientation may be the relationship of the current orientation, such as a flag orientation and the calibration orientation, such as a tubes-down orientation. This relationship determines that the correction value is A. This value may be applied to correct a measurement of, for example, a density or a volume flow rate measurement of a material in the sensor assembly. As can be seen in the above table, the current orientation and/or calibration orientation of the sensor assembly may be a tubes-down orientation, tubes-up orientation, and flag orientation. However, other orientations may be employed.

The vibratory meter <NUM>, meter electronics <NUM>, and method <NUM> described above may detect the orientation of the sensor assembly <NUM> and correct a measurement. As a result, the corrected measurement may be accurate. The orientation may be detected based on the sensor signals provided by the sensor assembly <NUM> and therefore does not require additional hardware. Accordingly, the orientation may be detected in any vibratory meter that can be configured to, for example, vibrate the sensor assembly <NUM> in two or more vibration modes. This may include vibratory meters installed in the field. The orientation may be detected by any suitable parameters of, or determined from, the sensor signals, such as using density values determined from two or more vibration modes and can therefore be configured as needed to reduce computing resources while preserving a desired amount of accuracy. Although any suitable parameter, such as tube-period or frequency, may be employed, the density values of the first order bend mode and the second order bend mode may be more accurate due to, for example, temperature correction that may be employed to determine the density values.

The detailed descriptions of the above embodiments are not exhaustive descriptions of all embodiments contemplated by the inventors to be within the scope of the present description. Indeed, persons skilled in the art will recognize that certain elements of the above-described embodiments may variously be combined or eliminated to create further embodiments, and such further embodiments fall within the scope and teachings of the present description. It will also be apparent to those of ordinary skill in the art that the above-described embodiments may be combined in whole or in part to create additional embodiments within the scope and teachings of the present description.

Claim 1:
A meter electronics (<NUM>) for detecting an orientation and compensating a measurement based on the detected orientation, the meter electronics (<NUM>) comprising:
an interface (<NUM>) configured to communicatively couple to a sensor assembly (<NUM>); and
characterised in that a processing system (<NUM>) is configured to detect an orientation of the sensor assembly (<NUM>) based on one or more vibration modes as observed in one or more sensor signals provided by the sensor assembly (<NUM>).