Rheological measurement device with optical data transfer

Abstract

A rheological measurement method and apparatus (e.g., viscometer or rheometer) for measuring rheological properties is disclosed. A rheological property, such as viscosity, is determined by detecting data corresponding to a torque between a drive shaft and a measurement shaft, generating an optical signal corresponding to the detected data, transmitting the corresponding optical signal by an optical transmitter supported by a rotational structure coupled to the drive shaft, the optical signal from the optical transmitter is received by an optical receiver supported by a fixed structure of the rheology measurement device, an electrical signal corresponding to the received optical signal is generated, and a measurement signal is generated based on an electrical signal corresponding to a torque between the drive shaft and the measurement shaft.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Application Serial No. 63 / 336,737, filed on April 29, 2022, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0003] The present subject matter relates to rheological measurement devices. Background Art

[0004] Rheological measuring devices such as rheometers and viscometers measure the rheological properties of a material (e.g., a liquid, suspension, or slurry). A viscometer typically measures the viscosity of a material. A rheometer typically measures other rheological properties (e.g., yield, creep, elasticity, etc.) in addition to or in lieu of viscosity. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] The accompanying drawings depict one or more embodiments by way of example only and not limitation. In the accompanying drawings, the same reference numerals represent the same or similar elements. From the detailed description below with reference to the accompanying drawings, it will be easy to understand the features of the disclosed different embodiments. The reference numerals are used with each element in this specification and in multiple views throughout the accompanying drawings. When there are multiple similar elements, a single reference numeral may be assigned to the similar elements, with the added letters representing the specific elements.

[0006] Unless otherwise specified, the various elements shown in the drawings are not drawn to scale. For clarity, the sizes of the various elements may be enlarged or reduced. The various drawings depict one or more embodiments and are presented by way of example only and should not be construed as limiting. The drawings include the following:

[0007] Figure 1A is a three-dimensional diagram of the rheological measurement device;

[0008] Figure 1B is a cross-sectional side view of the internal components of a rheometric device for driving a spindle within a material and detecting rheological parameters of the material.

[0009] Figure 2 A block diagram showing aspects of wireless power transfer and data flow within a rheological measurement device, partially in circuit diagram form.

[0010] Figure 3A is a circuit diagram of a resonant converter used in a rheological measuring device.

[0011] Figure 3B is used for Figure 3A The resonant converter and Figure 3C Illustration of the coil of a wireless power receiving circuit.

[0012] Figure 3C It is a circuit diagram of a wireless power receiving circuit used in a rheological measuring device.

[0013] Figure 4A is a circuit diagram of an optical data link transmitter used to transfer data within a rheological measurement device.

[0014] Figure 4B is an image of a circuit board with a superimposed diode pair branch layout pattern.

[0015] Figure 4C is a circuit diagram of an optical data link receiver used to transfer data within a rheological measurement device.

[0016] Figure 5 It is a circuit diagram of an angular displacement sensing circuit of an angle transducer circuit in a rheological measuring device.

[0017] Fig. 6A is a block diagram showing the layout of a transducer coil on a printed circuit board used in a transducer of a rheological measuring device.

[0018] Figure 6B is used for Fig. 6A Illustration of the spoiler coil of the transducer.

[0019] Fig. 7A , Figure 7B , Figure 7C , Fig.7D , Fig. 7E and Figure 7F is a block diagram partially represented in circuit diagram form of an alternative transducer example for use in a transducer of a rheological measuring apparatus.

[0020] Figure 8 is an illustration of a level sensor used with a rheometric measurement device.

[0021] Fig.9A , Fig. 9B and Fig. 9C is a flow chart of an example process performed by a rheometric measurement device. DETAILED DESCRIPTION

[0022] A rheological measurement method and apparatus (e.g., a viscometer / rheometer) for measuring rheological properties are disclosed. The rheological property (such as viscosity) is determined by detecting data corresponding to the torque between a drive shaft and a measuring shaft, generating an optical signal corresponding to the detected data, transmitting the corresponding optical signal via an optical transmitter supported by a rotating structure coupled to the drive shaft, receiving the optical signal from the optical transmitter via an optical receiver supported by a fixed structure of the rheological measurement apparatus, generating an electrical signal corresponding to the received optical signal, and generating a measurement signal based on the electrical signal corresponding to the torque between the drive shaft and the measuring shaft.

[0023] Additional objects, advantages and novel features of the examples will be set forth in part in the following description and will become apparent to those skilled in the art upon examination of the following and accompanying drawings, or may be learned by production or operation of the examples. The objects and advantages of the subject matter may be realized and obtained by the methods, means and combinations particularly pointed out in the appended claims.

[0024] In the following detailed description, many specific details are set forth by way of example in order to provide a thorough understanding of the relevant teachings. However, it should be clear to those skilled in the art that the present teachings can be practiced without such details. In other instances, well-known methods, processes, components, and circuits have been described at a relatively high level without details to avoid unnecessarily obscuring aspects of the present teachings.

[0025] As used herein, the term "coupled" refers to any logical, optical, physical or electrical connection, link, etc., whereby a signal or light generated or provided by one system element is imparted to another coupled element. Unless otherwise described, coupled elements or devices are not necessarily directly connected to each other and may be separated by intermediate components, elements or communication media that may modify, manipulate or carry light or signals.

[0026] Reference will now be made in detail to examples illustrated in the accompanying drawings and discussed below.

[0027] Figure 1A A rheological measuring device 100 (in the form of a viscometer) is depicted. The device 100 comprises a base 102 and a measuring unit 104 supported by the base 102. The illustrated measuring unit 104 comprises means for rotating a spindle 106 having a measuring head 108 within a housing 105 ( Figure 1B). The measurement unit 104 rotates the spindle and, in turn, the measurement head 108 within the material under test to detect torque, which is used to generate rheological properties of the material. A guard 110 may be positioned adjacent the spindle 106 and the measurement head 108 to prevent damage to the spindle 106 and the measurement head 108. A user interface 112 (e.g., a touch screen display) receives user input and presents rheological properties.

[0028] A spindle coupling 120 extending from a bottom portion of the measurement unit 104 is provided for releasably attaching the spindle 106 to the measurement unit 104. This enables different spindles / measurement heads to be attached. The coupling may be physically (e.g. by using mating threads) or magnetically secured.

[0029] Figure 2 Depicted are the components contained within the housing 105 of the measurement unit 104 which rotate the spindle coupling 120 and in turn the spindle 106 (with the measurement head 108) attached thereto. A base plate 122 within the housing provides support for a support structure 123 which supports the measurement unit 104. A stepper motor 124 under the control of a microprocessor (not shown) provides the rotational force for rotating a drive shaft 126.

[0030] A motor vibration mount 128 and a rubber coupling 130 are provided to reduce vibration during use. An upper bushing 132 radially supports an upper portion of the drive shaft 126 and a lower bushing 134 supports a lower portion of the drive shaft 126.

[0031] The fixed component 136 is supported by the fixed support structure 123 in a fixed area within the measuring unit 104. As used herein, the term fixed area / support structure refers to an area / support structure within the rheological measuring device that does not move during typical operation of the rheological measuring device. The fixed component 136 includes optical components, such as an optical receiver and an optional optical transmitter. The optical receiver and transmitter can be implemented as an optical transceiver. The fixed component may additionally include other components, such as a microprocessor for processing signals. In one example, the fixed component is a printed circuit board (PCB) including optical and electrical components.

[0032] When in use, the rotating component 138 is coupled to the drive shaft 126 in a rotating region relative to the fixed region. As used herein, the term rotating region / support structure refers to a region / support structure that rotates within the rheological measuring device during typical operation of the rheological measuring device. The rotating component 138 includes optical components, such as an optical transmitter and an optional optical receiver. The optical transmitter and receiver can be implemented as an optical transceiver. The rotating component may additionally include other components, such as a microprocessor for processing signals. In one example, the rotating component is a printed circuit board (PCB) including optical components and electrical components.

[0033] In one example, if Figure 1B As shown, the measurement shaft 150 is supported by the upper jewel bearing and pin 140 and the lower jewel bearing and pin 152. The measurement shaft 150 is coupled to the drive shaft 126 by a spring 146 (e.g., a coil spring) within a spring housing 148, which is coupled to the transducer housing 142. The transducer housing 142 houses an angular displacement transducer 144, which is coupled between the drive shaft 126 and the measurement shaft 150 to detect data corresponding to the torque between the drive shaft 126 and the measurement shaft 150. In this example, the displacement angle corresponds to the torque between the drive shaft 126 and the measurement shaft 150.

[0034] In one example, the displacement can be determined using a Rotary Variable Differential Inductance (RVDI) transducer to measure the angular displacement of a wound spring. According to this example, the same oscillating circuit can be used to measure the inductance of the two coils, with a differential response to a given angular displacement to minimize any circuit drift. The transducer output can be in the form of a frequency and can be measured using a counter with high accuracy. The resulting data is in pure digital form and is suitable for transmission over an optical data link.

[0035] In another example, displacement can be determined using a rotary variable differential transformer (RVDT) transducer that measures the angle of a wound spring. The analog output gives a very high resolution. According to this example, the output is digitized before optical transmission.

[0036] In another example, magnetic components (e.g., on-axis or radial) are used to determine displacement. In the on-axis example, an absolute end-of-axis magnetic sensor and a dipole magnet can be used to measure the angular displacement of a wound spring. Following this on-axis example, a similar magnet can be placed in the opposite direction (away from the sensor path) to cancel the earth's magnetic field, which can cause torque ripple while rotating.

[0037] In another example, an optical component (e.g., an optical radial or photointerrupter) is used to determine the displacement. In the optical radial example, an optical sensor in the form of an incremental or absolute encoder can be used to measure the angular displacement of the wound spring. In the photointerrupter example, the relative time between marks or the imaging of the relationship between the drive shaft markings and the sense shaft markings can be used to measure the angular displacement of the wound spring.

[0038] In another example not shown, the measuring shaft 150 is coupled to the drive shaft by a torsionable element coupled therebetween. According to this example, the transducer may be a strain gauge coupled to or integrated into the torsionable element. As non-limiting examples, the torsionable element may be spring steel, stainless steel, aluminum, beryllium copper, phosphor bronze, or an exotic alloy (e.g., such as found in Rolex watch springs).

[0039] In use, the fixed component 136 remains fixed in the fixed area when the stepper motor 124 drives the drive shaft 126. The measuring shaft 150 (rotating component) is connected to the drive shaft 126 and rotates in the rotating area relative to the fixed area. The drive shaft 126 is connected to the measuring shaft 150 (for example, via a spring or a torsion element) to impart a rotational force. The transducer 144 is connected between the drive shaft 126 and the measuring shaft 150 to sense the angular offset or force therebetween. The angular offset or force indicates the torque between the drive shaft 126 and the measuring shaft 150, which corresponds to the rheological properties (such as viscosity) of the fluid. The angular offset / force / torque is optically transmitted from the measuring shaft 150 in the rotating area to the fixed component 136 in the fixed area for processing to determine the rheological properties (for example, for storage in a memory or display on the user interface 112).

[0040] Figure 2 Depicted are example components of a circuit 200 for wireless power delivery and communication across an air gap 205 between a fixed region and a rotating region.

[0041] To wirelessly transfer power across the air gap 205, the primary coil 220 is driven by a resonant converter 222 to generate electromagnetic energy. The shunt capacitor 221 is used to adjust the impedance of the primary coil 220 to operate at the optimal frequency and load. By switching the two transistors 325 and 326 ( Figure 3A ), the current flows through a pair of inductors 323 and 324 ( Figure 3A ) is fed to excite the primary coil ( Figure 3A and Figure 3B ). The coil voltage can be used directly to achieve natural zero-crossing switching - thus forming a self-sustaining current-fed resonant converter. The primary coil 220, capacitor 221, resonant converter 222, inductor 323 / 324 and switch 325 / 326 can be mounted to a printed circuit board (PCB) in a fixed area.

[0042] Secondary coil 227 and shunt capacitor 228 (which may be similar or identical to primary coil 220 and shunt capacitor 221) receive the electromagnetic energy generated by primary coil 220. Figure 3C The depicted bridge rectifier and smoothing capacitor 229 rectifies and smoothes the alternating current (AC) power. The switching voltage regulator 230 regulates the power to a desired voltage (e.g., positive 5 volts) for providing power to components in the rotating area. The secondary coil 227, capacitor 228, bridge rectifier and smoothing capacitor 229, and switching voltage regulator 230 may be mounted to another PCB in the rotating area.

[0043] Such as Figure 4AThe illustrated optical transmitter 232 transmits data (e.g., transducer data) from the rotating region to the fixed region. The illustrated optical transmitter 232 includes six switched light emitting diodes (LEDs). The LEDs are arranged in three branches, with each branch having two LEDs (branch #1 includes LED D1 and LED D2, branch #2 includes LED D3 and LED D4, and branch #3 includes LED D5 and LED D6). Each pair of LEDs in a branch is arranged in opposite directions from a center point, and as shown in FIG. Figure 4B As shown in FIG, the branches are equally spaced to maintain contact with the photodiode 435 ( Figure 4C ) line of sight. The optical transmitter 232 may be mounted to a PCB in the rotating area.

[0044] There may also be Figure 4A An optical transmitter 233 is shown to transfer data (eg, configuration or firmware updates) from the fixed area to the rotating area. The optical transmitter 233 may be mounted to a PCB in the fixed area.

[0045] Such as Figure 4C The optical receiver 231 shown receives data (e.g., transducer data) from the rotating area in the fixed area. The photodiode 435 in the fixed area receives the optical signal from the optical transmitter 232 in the rotating area and generates a corresponding analog electrical signal. The amplifier 436 (such as a high-speed operational amplifier (op-amp)) amplifies the electrical signal and the processing circuit (such as a Schmitt trigger 437) generates an associated logic level signal. The optical receiver 231 can be mounted to a PCB in the fixed area. The optical transmitter 233 and the optical receiver 231 can be implemented as an optical transceiver.

[0046] There may also be a light receiver 234, such as Figure 4C , to receive data (e.g., configuration or firmware update) in the rotating area from the optical transmitter 233 in the fixed area. The optical receiver 234 may be mounted to a PCB in the rotating area. The optical transmitter 232 and the optical receiver 234 may be implemented as optical transceivers.

[0047] Angular displacement sensing circuit 239 ( Figure 5 ) senses the angular displacement between the drive shaft 126 and the measurement shaft 150. The angular displacement sensing circuit may include a resonant circuit 541, two printed circuit board (PCB) coils 542, 543, a spoiler 644 ( Fig. 6A and Figure 6B), and coil selector 545. The spoiler 644 angular position changes the coil inductance in a differential manner. Coils 542, 543 are fed to the same resonant circuit 541 to generate a frequency output proportional to the coil inductance. The differential frequency measurement reduces the thermal drift effects of the resonant circuit 541 by selecting one coil at a time. In the example, the spoiler 644 operates at + / -37.5 degrees (i.e., 0 degrees to 75 degrees full power). The spoiler 644 can be made of a conductive material such as aluminum or copper to reduce the coil inductance by covering the coil inductance due to the eddy current effect.

[0048] The rheological measurement device may include other sensing circuits, such as an onboard temperature sensor 240. The microcontroller 238 may receive data from the sensing circuits for light transmission from the rotating region to the fixed region, for example, for further processing to determine the rheological properties of the material to be measured. The rotating microcontroller 238 may additionally receive data from light receivers in the rotating region, for example to selectively activate one or more sensing circuits and update firmware. The data (such as commands) sent to the rotating microcontroller can be used to selectively activate the mechanical device to, for example, turn on / off different springs / torqueable elements, thereby producing a single instrument with the ability to measure substantially different torque ranges. In addition, commands can be sent to, for example, turn on / off normal force control (active cancellation), heat or cool the sample, etc.

[0049] Fig. 7A , Figure 7B , Figure 7C , Fig.7D , Fig. 7E and Figure 7F is a block diagram depicting an alternative sensor example for use with a microcontroller 702 to detect angular offset or force between a drive shaft 126 and a measurement shaft 150 of a rheometry device. Fig. 7A A linear variable differential transformer (LVDT) / rotary variable differential transformer (RVDT) sensor is depicted. Figure 7B A strain gauge / torque cell sensor is depicted. Figure 7C An on-shaft magnetic sensor is depicted. In one example, the on-shaft magnetic sensor includes a magnet on the end of the measuring shaft 150 (eg, at the upper jewel bearing and pin 140) and a magnetic sensor on the PCB in the rotating region adjacent to the magnet. Fig.7D An off-axis magnetic sensor is depicted. Fig. 7E A transmissive light sensor is depicted. Figure 7F A reflective optical sensor is depicted.

[0050] Figure 8is an illustration of a level sensor 800 used with a rheometric device to measure whether it is level, for example, to ensure acceptable levelness of a sensitive instrument. The level sensor includes a three-dimensional (3D) accelerometer 802 positioned on the surface of a PCB that rotates within the rheometric device and provides measurements to a microprocessor 702. In one example, the 3D accelerometer 802 is calibrated to indicate a level condition in a static state. If the 3D accelerometer is rotated and the g readings in the x and y directions are monitored, no prior calibration is necessary. To achieve a level condition, the adjustment foot is moved up (automatically / manually) and down until there is no change in the g readings in the x and y directions. This avoids the effects of errors in the 3D accelerometer 802 due to heat, aging, and calibration errors.

[0051] Fig.9A , Fig. 9B and Fig. 9C is a flow chart of an example process performed by a rheometric device. A flow chart may describe operations as a sequential process, however, many of these operations may be performed in parallel or simultaneously. In addition, the order of the operations may be rearranged. A process terminates when its operations are completed. A process may correspond to a method, procedure, etc. The steps of a method may be performed in whole or in part, may be performed in combination with some or all steps of other methods, and / or may be performed by any number of different systems, such as FIG. 1- Figure 8 The system described in .

[0052] Fig.9A is a flow chart 900 depicting a method for generating rheological measurement data, such as viscosity. At block 902, a rheological measurement device inserts a spindle into a material to be tested such that a measurement head on the spindle is fully inserted into the material.

[0053] At block 904, the rheometer rotates the spindle. The rheometer can be accelerated uniformly from a stop to a desired rotation rate. Additionally, the rheometer can be periodically started / stopped and can raise / lower the spindle.

[0054] At block 906, a measurement sensor (such as a transducer) obtains measurement data. In one example, the transducer detects data corresponding to the torque between the drive shaft 126 and the measurement shaft 150 (coupled to the spindle). In another example, a temperature sensor detects data corresponding to the temperature within the rheological measurement device. In another example, a level sensor senses the orientation of the rheological measurement device (e.g., whether it is horizontal).

[0055] At block 908, the optical component optically transmits the data, for example, from the rotating region to the fixed region. The optical component may receive an electrical signal from the measurement sensor, convert the electrical signal into an optical signal transmitted from the rotating region via an LED, receive the transmitted optical signal in the fixed region, and convert the received optical signal into an electrical signal carrying the data for processing.

[0056] At block 910, a processor within the rheometer receives and processes the data in the electrical signal. In one example, the processor of the rheometer identifies the viscosity of the material being measured by processing the data corresponding to the torque.

[0057] At block 912, a processor within the rheological measurement device stores and presents the processed data. In one example, the processor of the rheological measurement device stores the identified viscosity of the material to be measured in a memory accessible to the processor. In another example, the processor sends the viscosity to a screen for presentation to a user.

[0058] Fig. 9B 9 is a flow chart depicting a method for transferring data generated in a fixed region to a rotating region (e.g., to configure or update a measurement sensor). At block 922, a processor (located in the fixed region) assembles instructions for configuring or updating a measurement sensor in the rotating region. These instructions may include configuration data, firmware updates, or other data.

[0059] At block 924, the optical component transmits the data / instructions, for example, optically from the fixed region to the rotating region. The optical component may receive an electrical signal from the processor, convert the electrical signal into an optical signal transmitted from the fixed region via an LED, receive the transmitted optical signal in the rotating region, and convert the received optical signal into an electrical signal carrying the data / instructions for processing.

[0060] At block 926, the processor executes the data / instructions in the received instructions. In one example, the processor of the measurement device performs a firmware update of the measurement device. In another example, the processor switches when the measurement device is active.

[0061] Fig. 9C 9 is a flow chart depicting a method for wirelessly transferring power from a fixed region of a rheometer to a rotating region (e.g., to power components in the rotating region). At block 932, power is provided in the fixed region. The power may be DC power generated from an AC power outlet.

[0062] At block 934, power is wirelessly transferred from the fixed region to the rotating region. In an example, power is wirelessly transferred as electromagnetic energy between a primary coil in the fixed region and a secondary coil in the rotating region.

[0063] At block 936 , the wirelessly transferred power is used to power one or more components in the rotating area.

[0064] It will be understood that the terms and expressions used herein have the ordinary meaning, as given to such terms and expressions for the corresponding queries and research fields to which they correspond, except where specific meanings have been otherwise elaborated herein. Relational terms such as first and second, etc., may be used only to distinguish one entity or action from another entity or action, without requiring or implying any actual such relationship or order between these entities or actions. The terms "comprises", "comprising", "includes", "including" or any other variation thereof are intended to cover non-exclusive inclusions, so that a process, method, article or device that includes or includes a series of elements or steps includes not only those elements or steps, but may also include other elements or steps that are not explicitly listed or inherent to such processes, methods, articles or devices. Without further limitation, an element preceded by "a" or "an" does not exclude the presence of additional identical elements in the process, method, article or device that includes the element.

[0065] Unless otherwise indicated, any and all measurements, values, ratings, positions, amplitudes, dimensions, and other specifications set forth in this specification (including in the appended claims) are approximate and imprecise. Such quantities are intended to have reasonable ranges consistent with the functions to which they are related and with the customary practices in the art to which they belong. For example, parameter values, etc., whether or not qualified by degree terms (e.g., approximately, substantially, or about) may vary from the recited quantities by as much as ±10%, unless expressly specified otherwise.

[0066] The embodiments shown herein are described in sufficient detail to enable those skilled in the art to implement the disclosed teachings. Other examples may be used and derived therefrom, so that structural and logical substitutions and changes may be made without departing from the scope of the present disclosure. Therefore, the detailed description should not be taken as limiting, and the scope of the different examples is limited only by the appended claims and the full scope of equivalents to which these claims are assigned.

Claims

1. A rheological measuring device, comprising: a drive shaft configured to be driven by a motor, a measuring shaft coupled to the drive shaft; Fixed structure; a rotating structure coupled to the drive shaft; a transducer configured to detect data corresponding to a torque between the drive shaft and the measurement shaft; an optical transmitter, the optical transmitter being supported by the rotating structure, the optical transmitter being configured to generate an optical signal corresponding to the detected data; an optical receiver supported by the fixed structure, the optical receiver configured to receive the optical signal from the optical transmitter and generate an electrical signal corresponding to the received optical signal; a first induction coil coupled to the fixed structure; a second induction coil coupled to the rotating structure, the first induction coil and the second induction coil being positioned relative to each other to transfer power from the first induction coil to the second induction coil; as well as A processor is coupled to the optical receiver, the processor being configured to receive the electrical signal and to generate a measurement signal corresponding to the torque between the drive shaft and the measurement shaft based on the electrical signal.

2. The device according to claim 1, wherein: The transducer is coupled to the rotating structure and the measurement axis.

3. The apparatus according to claim 1, further comprising: A twistable element couples the drive shaft to the measurement shaft.

4. The device according to claim 3, wherein: The transducer includes a strain gauge integrated into or coupled to the twistable element.

5. The apparatus according to claim 1, further comprising: another optical transmitter supported by the fixed structure, the optical transmitter configured to transmit another optical signal; as well as Another optical receiver is supported by the rotating structure, and is configured to receive the another optical signal from the another optical transmitter.

6. The device according to claim 1, wherein: The transducer includes at least one of a rotary variable differential inductor (RVDI) transducer or a rotary variable differential transformer (RVDT) transducer.

7. The device according to claim 1, wherein: The transducer comprises: On-axis magnets; and An additional magnet is configured to cancel the effects of the earth's magnetic field.

8. The device according to claim 1, wherein: The fixed structure includes a first printed circuit board, the rotating structure includes a second printed circuit board, the optical receiver is mounted on the first printed circuit board, and the optical transmitter is mounted on the second printed circuit board.

9. The apparatus according to claim 1, further comprising: A three-dimensional accelerometer is supported by the rotating structure for leveling.

10. A rheological measurement method, comprising: detecting data corresponding to a torque between a drive shaft and a measuring shaft of a rheometer; generating an optical signal corresponding to the detected data; transmitting the corresponding optical signal via an optical transmitter supported by a rotating structure coupled to the drive shaft; receiving the optical signal from the optical transmitter via an optical receiver supported by a fixed structure of the rheological measuring device; transferring power between a first induction coil coupled to the fixed structure and a second induction coil coupled to the rotating structure; generating an electrical signal corresponding to the received optical signal; as well as A measurement signal is generated based on the electrical signal corresponding to the torque between the drive shaft and the measurement shaft.

11. The method according to claim 10, wherein: A transducer is coupled to the rotating structure and the measuring axis to detect the data.

12. The method according to claim 10, wherein: A twistable element couples the drive shaft to the measurement shaft.

13. The method according to claim 12, wherein: The data is detected using strain gauges integrated into or coupled to the twistable element.

14. The method according to claim 10, further comprising: transmitting another optical signal via another optical transmitter supported by the fixed structure; as well as The further optical signal from the further optical transmitter is received at an optical receiver supported by the fixed structure.

15. The method according to claim 10, wherein: The measurement signal is generated by a transducer, and wherein the transducer comprises at least one of a Rotary Variable Differential Inductor (RVDI) transducer or a Rotary Variable Differential Transformer (RVDT) transducer.

16. The method according to claim 10, wherein: The measurement signal is generated by a transducer, and wherein the transducer comprises an on-axis magnet and an additional magnet configured to cancel the influence of the earth's magnetic field.

17. The method according to claim 10, wherein: The fixed structure includes a first printed circuit board, the rotating structure includes a second printed circuit board, the optical receiver is mounted on the first printed circuit board, and the optical transmitter is mounted on the second printed circuit board.

18. The method according to claim 10, further comprising: The rheological measurement device is leveled using a three-dimensional accelerometer supported by the rotating structure.

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