Container fill level measurement and management

A content fill level sensor is disclosed. The sensor includes a transmitter located proximal to a portion of a container cover that is configured to engage an opening of a container. The sensor also includes a waveguide extending from the transmitter such that the waveguide includes a distal end that is configured to be located within an interior of the container when the container cover engages the container.

BACKGROUND OF THE INVENTION

Distances can be measured by determining the time it takes for a signal to bounce off an object located at the desired distance. For example, if the speed of the signal and the travel time of the signal are known, a distance traveled by the signal can be measured. However in certain environments, it may be difficult to obtain an accurate distance measurement. For example, a configuration of the environment may make it difficult to place an instrument that can accurately measure a desired distance.

DETAILED DESCRIPTION

A fill level sensor is disclosed. For example, the fill level sensor measures the amount of liquid contained in a bottle. In some embodiments, the fill level sensor includes an acoustic transmitter located proximal to a portion of a container cover that is configured to engage a container opening. For example, the fill level sensor is included in a cap of a bottle and includes a speaker that will transmit a signal that will be utilized to measure a liquid fill level of the bottle. In some embodiments, the fill level sensor also includes a waveguide extending from the transmitter such that the waveguide includes a distal end that is configured to be located within the container interior when the container cover engages the container. For example, the waveguide guides a signal transmitted by the transmitter to a desired location and direction where the signal is directed towards contents filling a container. The signal may reflect off the container contents and arrive at a receiver of the fill level sensor that analyzes the received reflected signal to determine the fill level of the container.

FIG. 1is a diagram illustrating an embodiment of a fill level sensor engaged in a container. Container102is filled with a liquid. In the example shown, fill level sensor100is configured as a bottle cap with a spout. The liquid fill level of container102may be determined by measuring the distance between sensor100and the liquid surface of container102. As shown by line104, a transmitter of sensor100sends out a signal (e.g., ultrasonic signal) that gets reflected by the surface of the liquid. The reflected signal is detected by a receiver of sensor100.

By measuring the amount of time it took to receive the reflected signal, the distance traveled by the signal before being reflected (e.g., distance between sensor100and liquid surface is half of the total distance traveled by the signal) may be determined by multiplying the amount of time by the speed of the signal (e.g., speed of sound).

In some embodiments, to determine the amount of time it took to receive the reflected signal, the received reflected signal is filtered to isolate the desired signal (e.g., band-pass filter the received signal), amplified, and analyzed to detect peaks that correspond to when the reflected signal was received. In some embodiments, in order to achieve consistent and accurate measurements, gain at various depths is varied to help increase the received signal strength. Gain can be varied by changing the frequency and the number of pulses. For example, higher frequency and lower number of pulses may lead to better resolution at the top of the bottle/container while lower frequency and higher number of pulses may lead to better resolution towards the bottom of the bottle/container (e.g., the act of changing the pulses and frequency is akin to organ pipe tuning). Bottles and containers may have dead zones where no measurements can be obtained due to standing waves. By continuing to pulse or use large number of pulses at the same frequency, the dead zones may be overcome. A predetermined beginning portion (e.g., predetermined amount of time in the beginning of the signal) of the received signal may be ignored when analyzing the signal to ignore signals that were detected due to coupling between the transmitter and receiver of sensor100. For example, when the transmitter transmits the signal, the signal may be received by the receiver of sensor100(e.g., conducted through sensor100, due to undesired reflection, etc.) before the signal is reflected by the contents of the container, and the undesired received signals received in the beginning portion of the received signal are ignored when identifying the desired received reflected signal.

If the total distance between the bottom of container102and sensor100is known, the fill height of container102can be determined (e.g., total distance between bottom and sensor100minus distance between sensor100and liquid surface). If the shape and volume of the bottle are known, the volume of liquid contained in container102may be determined. For example, a table/database/data structure that maps fill level (e.g., fill height, height between liquid surface and sensor100, etc.) to liquid volume of the container is utilized to determine liquid volume corresponding to the determined fill level. Different tables/databases/data structures may exist for different types of containers.

Sensor100includes a transmitter for transmitting the reflected signal and a receiver for receiving the reflected signal. However, due to the narrow opening of container102, the placement of the transmitter and receiver in sensor100is limited to the narrow configuration of the bottle opening. If the transmitter and receiver are placed too close together, the transmitter and receiver may become coupled together. For example, the receiver may receive a strong signal from the transmitter as soon as the transmitter transmits a signal and the receiver may require a long settling time before the receiver is able to detect the desired reflected signal. If the distance between sensor100and the liquid surface is small, the desired reflected signal may be received before the receiver has settled and the receiver is unable to detect the desired reflected signal. In some embodiments, the transmitter and receiver of sensor100are vertically offset from each other to create a desired amount of separation distance between the transmitter and receiver. The separation distance may reduce the coupling of the transmitter and receiver and allow dampening of the transmitted signal propagated between the transmitter and the receiver through sensor100. However, the vertical separation of the transmitter and the receiver may create undesired reflections within the container (e.g., reflections from the neck of a bottle) that make it difficult to identify the signal reflected from the liquid surface. In some embodiments, a waveguide extending from the transmitter is utilized to direct the signal transmitted by the transmitter towards the desired direction and location to minimize undesired effects.

FIG. 2Ais a vertical cross-sectional diagram illustrating an embodiment of a fill level sensor. In some embodiments, sensor200is sensor100ofFIG. 1.FIG. 2Bis a vertical cross-sectional diagram illustrating an alternative embodiment of a fill level sensor. In the examples shown, sensor200is configured as a bottle stopper with a spout. As shown inFIG. 2A, sensor200includes flexible container coupling ridges220(e.g., rubber rings) that allows sensor200to be coupled to and seal an opening of a container (e.g., as shown inFIG. 1). However, in other embodiments, sensor200may be configured as a different cover of a container. For example, the components of sensor200may be included in a screw-on cap or any other cap that engages a container.

Sensor200includes circuit board212. For example circuit board212is a printed circuit board. Circuit board212may connect together one or more of the following: a processor, a memory, a data storage, a connector, an integrated chip, a transmitter, a receiver, an accelerometer, a tilt sensor, a solar panel, a display, a gyroscope, a wireless data communication signal transmitter (e.g., a component able to communicate using Bluetooth (e.g., Bluetooth Low Energy), Wi-Fi, other wireless protocol, etc.), and other electrical components. For example, a processor connected to circuit board212provides a command to transmit an acoustic signal using a transmitter and processes a received signal to determine a fill level indicator. The fill level indicator may be transmitted wirelessly to another device such as a mobile device, a computer, a display device, or any other computing or display device using a wireless data communication transmitter. For example, when a change in depth is detected, a data packet is sent, and the data packet includes a device media access control (MAC) identifier, a depth value (e.g., in mm), an identifier of power left (e.g., in secs), and a real time clock value (e.g., 32 bit value). Circuit board212is connected to battery206. Battery206provides power to the circuit of circuit board212. Battery206may be rechargeable and/or replaceable. The housing of sensor200may be composed of one or more materials. Examples of the materials include a food grade polymer, plastic, rubber, stainless steel, and other metals.

Sensor200includes spout208. Spout208is a part of a channel (e.g., tube) that allows container contents (e.g., liquid) to pass through to the tip opening of spout208from a bottom of sensor200. For example, a liquid contained in a container that is capped by sensor200is able to pass through sensor200and exit the opening of spout208when the container capped by sensor200is tipped over. In some embodiments, circuit board212includes a hole that accommodates the channel (e.g., tube) that allows container contents (e.g., liquid) to pass through the circuit board. In other embodiments, spout208may not exist in sensor200. In some embodiments, sensor200includes a vent pipe (not shown) that allows air to enter a container capped by sensor200as a content of the container is poured out through spout208. In some embodiments, sensor200includes a motor (not shown) that pumps out contents of the container capped by sensor200.

Circuit board212is connected to transmitter204. In some embodiments, transmitter204is an acoustic transmitter (e.g., ultrasonic signal transmitter). For example, transmitter204is a speaker. In some embodiments, transmitter204is a piezoelectric speaker. In some embodiments, transmitter204is configured to transmit a signal within the ultrasonic frequencies. In some embodiments, transmitter204is configured to transmit a signal between 20 kHz and 400 kHz, inclusive. In some embodiments, transmitter204is configured to transmit a 29 kHz signal. In some embodiments, transmitter204is an acoustic impulse generator.

Receiver214is connected to circuit board212via connector210. Examples of connector210include a wire, a bus, a flexible printed circuit board, and any other connector able to transmit a signal. In some embodiments, receiver214is an acoustic receiver (e.g., ultrasonic signal receiver). In some embodiments, receiver214is a microphone. In some embodiments, receiver214is a microelectromechanical systems (MEMS) microphone. For example, receiver214is 2 millimeter×3 millimeter in size.

Waveguide202extends from transmitter204. For example, waveguide202includes a hollow chamber (e.g., tube) that guides and propagates an acoustic signal emitted by transmitter204from one end of the chamber to the other end of the chamber. For example, signal emitted by transmitter204enters waveguide202at the signal input end of the hollow chamber and exits out its output end of the hollow chamber (e.g., distal end). In some embodiments, waveguide202aids in directing an acoustic signal (e.g., ultrasonic signal, acoustic impulse) emitted by transmitter204towards the direction of the distance to be measured (e.g., towards bottom of sensor200that will be facing contents of a container capped by sensor200).

In some embodiments, it is desirable to reduce and/or attempt to eliminate any signal reflections within the chamber of waveguide202as the signal is guided from one end to the other end of waveguide202. For example, any undesired reflection may mask and hinder detection of the signal reflected by container contents desired to be detected. Any sudden change in the shape of the hollow chamber may create an impedance mismatch that creates a reflection within the hollow chamber of waveguide202. In some embodiments, the interior wall of the hollow chamber of waveguide202is substantially smooth to prevent impedance mismatches. In some embodiments, a shape and/or size of a horizontal cross section of waveguide202does not change by more than one percent per millimeter of vertical distance between the signal input end closest to transmitter204to the other signal output end (e.g., distal end). In some embodiments, a shape of the opening of one end of the hollow chamber is different from a shape of the opening of the other end of the hollow chamber. For example, a shape of an opening of the transmitter may be different than a desired shape of the signal output end of waveguide202(e.g., desired shape to improve directionality of the signal in container). In one example, the signal input end of the chamber of waveguide202is shaped in a first shape (e.g., elliptical shape) and the output opening end of the other end of the chamber of waveguide202is shaped in a second shape (e.g., circular shape). The change in horizontal cross-sectional shape of the hollow signal propagation chamber may gradually morph from the first shape to the second shape across the vertical length of waveguide202. For example, the minor axis of the elliptical shape signal input opening gradually is expanded (e.g., flair out smoothly) to generally match the major axis of the elliptical shape in the output end of waveguide202.

In some embodiments, a cross-sectional area of a signal output opening of the chamber of waveguide202is at least as large as a cross-sectional area of a signal input opening of the other end of the chamber of waveguide202that receives the signal from transmitter204. For example, the cross-sectional area of the signal output opening of waveguide202is substantially equal to the cross-sectional area of the signal input opening in one embodiment. In another example, the cross-sectional area of the signal output opening of waveguide202is greater than the cross-sectional area of the signal input opening.

In some embodiments, the horizontal cross-sectional area of the hollow chamber of waveguide202is only greater or equal to a previous horizontal cross-sectional area of the hollow chamber from the input opening to the output opening of waveguide202. For example, in order to ensure that the amplitude of an acoustic signal outputted by transmitter204is maintained as much as possible, the cross-sectional area of the chamber of waveguide202never decreases as the acoustic signal is traveling down the chamber of waveguide202. In some embodiments, the horizontal cross-sectional area of the chamber of waveguide202is generally increasing as the signal emitted by transmitter204travels down waveguide202towards the distal end of waveguide202.

In some embodiments, the interior hollow chamber of waveguide202is coated with a dampening material. For example, an acoustic signal dampening material (e.g., rubber like material) coats plastic walls of the hollow chamber and the coating may assist in reducing the amount of signal that gets transferred to receiver214from the portion of the signal that impacts the walls of the hollow chamber. In some embodiments, an interior chamber of waveguide200is filled with an acoustically permeable material. In some embodiments, an open end of waveguide202is touching transmitter204. For example, a rubberized end of waveguide202seals signals emitted by transmitter204within an air chamber of waveguide202. In some embodiments, a size of a signal input opening of waveguide202near transmitter204is at least as large as a transmitter opening of transmitter204. For example, transmitter204includes an opening where an acoustic signal is outputted (e.g., speaker grill opening) and the opening of the transmitter is positioned within the signal input opening of waveguide202that is at least as large. In some embodiments, a shape and size of a signal input opening of waveguide202near transmitter204is substantially the same as a transmitter opening of transmitter204. In some embodiments, waveguide202is attached to transmitter204. For example, transmitter204and waveguide202are attached together by glue. In some embodiments, waveguide202is mechanically coupled to transmitter204.

In some embodiments, a height of waveguide202(e.g., distance between the input and output openings) is approximately 20 millimeters. In some embodiments, a height of waveguide202(e.g., distance between the input and output openings) is approximately less than or equal to 60 millimeters. In some embodiments, widths of a hollow chamber of waveguide202(e.g., horizontal cross-sectional area) is approximately is less than or equal to 12 millimeters. In various embodiments, the shape, length, and width of waveguide202may be any combination of shape, length and width configurations and sizes.

In some embodiments, waveguide202is attached to receiver chamber222of receiver214. For example as shown, receiver214is recessed in receiver chamber222area that is included/attached to the side of waveguide202. Waveguide202and receiver chamber222may be composed of the same or different materials. Examples of the materials include a food grade polymer, plastic, rubber, stainless steel, and other metals. In some embodiments, waveguide202is not attached to receiver chamber222. For example, receiver chamber222is attached to the housing of sensor200and not directly attached to waveguide202.

In some embodiments, a placement distance (e.g., vertical distance) between transmitter204and receiver214is at least 0.6 millimeters. For example, by vertically offsetting the transmitter204and receiver214, signal coupling between transmitter204and receiver214through materials of sensor200is reduced and allows better detection of a desired reflected signal received by receiver214. In some embodiments, at least a portion of transmitter204horizontally overlaps receiver214in the horizontal position. For example, due to their vertical offset, transmitter204is able to horizontally overlap receiver214(e.g., at least a portion of width of transmitter204overlaps at least a portion of width of receiver214). In some embodiments, the signal output opening of waveguide202is substantially on the same vertical location as the opening of receiver chamber222. For example, by placing the signal output opening of waveguide202on the same vertical location as the opening of receiver chamber222, an effect of a signal reflection caused by the impedance mismatch of the output opening of waveguide202on the detection of a desired received reflected signal is minimized. In some embodiments, the signal output opening of waveguide202is parallel to the opening of receiver chamber222.

In some embodiments, because debris, liquid, and other materials may enter the chamber of waveguide202and receiver chamber222(e.g., when using spout208to pour out contents of the container), the chamber of waveguide202and receiver chamber222are protected (e.g., to protect transmitter204and receiver214). In some embodiments, a protective layer material covers the output opening of waveguide202and the opening of receiver chamber222. Ideally the protective material must not allow undesired material through to the chambers while at the same time allowing signals (e.g., acoustic signals) to pass through. Protective material216covers the output opening of waveguide202and is attached to the opening edges of waveguide202. Protective material218covers the output opening of receiver chamber222and is attached to the opening edges of receiver chamber222. In some embodiments, protective material216and protective material218are the same continuous material. For example, a single connected sheet includes both protective material216and protective material218. In some embodiments, protective material216and protective material218are not continuous materials. For example, in order to maximize decoupling of the transmitted signal of transmitter204and the received signal of receiver214, protective material216and protective material218are not made of the same continuous material. In some embodiments, protective material216and protective material218are different materials. Examples of protective material216and protective material218include one or more of the following: mylar sheet, waterproof mesh, acoustic sheet, Teflon, Gortek and any other appropriate mesh or membrane. For example, a mylar sheet covering does not allow liquid to pass through while acting like a drum to allow acoustic signals to pass through. In some embodiments, protective material216and/or protective material218are acoustically transmissive liquid blocking materials. In some embodiments, protective material216and/or protective material218are optional.

In an alternative embodiment, rather than utilizing a separate transmitter and a separate receiver, a transceiver that acts as both a receiver and transmitter is utilized. For example, receiver214is not utilized and transmitter204is a transceiver (e.g., piezoelectric transceiver).

FIGS. 3A-3Bare bottom view diagrams illustrating embodiments of a fill level sensor. Sensor200is sensor200ofFIG. 2A or 2B. Sensor200includes flexible ridges220(e.g., rubber rings) that allows sensor200to be coupled to and seal an opening of a container (e.g., as shown inFIG. 1andFIG. 2A). Spout input opening209allows contents (e.g., liquid contents of a container capped by sensor200) that enter through spout input opening209to be channeled and outputted through spout208(shown inFIG. 2A). The signal output end of waveguide202is shown inFIGS. 3A and 3B. Receiver214is recessed inside receiver chamber222. In some embodiments, protective material216covers the shown output opening of waveguide202and is attached to the shown opening edges of waveguide202. In some embodiments, protective material218covers the shown output opening of receiver chamber222and is attached to the shown opening edges of receiver chamber222. Vent output opening224(e.g., opening of a vent pipe) allows air to enter a container capped by sensor200as contents of the container is poured out through spout input opening209. In order to show the internal components of various embodiments of sensor200, one or more components of sensor200are not shown inFIGS. 3A-3B.

FIGS. 4A-4Care profile diagrams illustrating embodiments of a fill level sensor. The diagrams show various external and internal components of various embodiments of fill level sensor200. In order to show the internal components of various embodiments of sensor200, one or more components of sensor200are not shown inFIGS. 4A-4C.

FIG. 5is a diagram showing alternative embodiments of a waveguide. In some embodiments,FIG. 5shows alternative shapes of waveguide202shown inFIGS. 2, 3 and 4A.

Waveguides502-512show vertical cross-sectional diagrams of different embodiments of waveguide shapes. For example, although waveguides502-512are tubular in shape, the cross-sectional diagrams are shown to illustrate the hollow interior of the waveguides. Waveguide502includes substantially straight side walls that extend straight from the signal input end of waveguide502that receives signal input from transmitter204to the signal output end of waveguide502. Waveguide504includes linearly sloped side walls that extend smoothly outward from signal input end of waveguide504that receives signal input from transmitter204to the signal output end of waveguide504. Waveguide506includes exponentially sloped side walls that extend smoothly outward from the signal input end of waveguide506that receives signal input from transmitter204to the signal output end of waveguide506.

In some embodiments, the output end of a waveguide is configured to accommodate a waveguide extension tube (e.g., tube with two open ends). For example, for certain types of containers, it may be beneficial to guide a signal outputted by transmitter204further down in to the container to measure fill level. By utilizing a waveguide extension tube, a waveguide is able to extend beyond the sensor200. By extending the waveguide further down the container, undesired reflection in the container may be minimized. In some embodiments, the output end of the waveguide is enlarged to accommodate coupling with a waveguide extension tube. For example, in order to minimize the impedance mismatch between the output end of a waveguide with the input end of the waveguide extension tube to be coupled, the transition between the interior output opening of the sensor waveguide and interior input opening of the extension tube must be smooth. In some embodiments, the interior opening widths of waveguide extension tubes514,516and518are substantially similar to interior opening widths of waveguides508,510, and512, respectively.

Waveguide extension tubes514,516and518are shown in profile view. Although waveguide extension tubes514,516and518are shown separated from waveguides508,510, and512, respectively, to show the different components, waveguide extension tubes514,516and518may be inserted into waveguides508,510, and512, respectively, to be coupled (e.g., friction coupling, mechanical coupling, etc.) together. To accommodate for the thickness of the waveguide extension tube, waveguides508,510, and512include bell shaped ends that can be coupled with waveguide extension tubes514,516, and518, respectively to create a relatively smooth transition between the interior walls of the sensor waveguides and the waveguide extension tubes. In some embodiments, a waveguide extension tube is removable from a sensor waveguide. In some embodiments, a waveguide extension tube is permanently coupled (e.g., glued) to a sensor waveguide. Examples of the materials that make up waveguide extension tubes514,516, and518include a food grade polymer, plastic, rubber, stainless steel, and other metals.

FIG. 6is a diagram showing a receiver extension tube. In some embodiments,FIG. 6shows an embodiment of receiver214and receiver chamber222of sensor200shown inFIGS. 2 and 3. Receiver214and receiver chamber222are shown in cross sectional view and receiver extension tube600is shown in profile view. Although receiver extension tube600is shown separated from receiver chamber222to show the different components, receiver extension tube600may be inserted into receiver chamber222to be coupled together. By utilizing a receiver extension tube, a receiver chamber is able to extend beyond the sensor200.

In some embodiments, the output end of receiver chamber222is configured to accommodate receiver extension tube600(e.g., tube with at least two open ends). For example, for certain types of containers, it may be beneficial to receive a signal outputted by transmitter204further down in to the container within receiver extension tube600. By extending further down the container the receiver chamber that will guide a received signal to receiver214, undesired reflection in the container may be rejected from entering the extended receiver chamber. Receiver chamber222is configured to accommodate coupling (e.g., friction coupling, mechanical coupling, etc.) with receiver extension tube600. The size of receiver chamber222is large enough to accommodate for the thickness of receiver extension tube600. In some embodiments, a receiver extension tube is removable from receiver chamber222. In some embodiments, receiver extension tube600is permanently coupled (e.g., glued) to receiver chamber222. In some embodiments, at least one end of receiver extension tube600is sealed with an acoustically transmissive liquid blocking material (e.g., material218ofFIG. 2AofFIG. 3B). The lengths, widths, and/or shape of receiver extension tube600may vary across different embodiments. Examples of the materials that make up receiver extension tube600include a food grade polymer, plastic, rubber, stainless steel, and other metals. In some embodiments, the interior opening width of receiver extension tube600is at least as large as a size of an opening of receiver214that is configured to receive a signal.

In the example shown, receiver extension tube600includes optional pairs of holes/slots602,604, and606. Each hole of each pair is on the same horizontal axis position (e.g., vertical position) substantially opposite one another on receiver extension tube600. Although three pairs have been shown, any number of pairs may exist in other embodiments. In some embodiments, pairs of holes/slots602,604, and606allow receiver214to act as a shotgun/parabolic microphone. For example, receiver214is able to directionally better detect signals received at the bottom of receiver extension tube600rather than the sides of extension tube600. Signals received at the sides of receiver extension tube600(e.g., received through holes/slots602,604, and606) may be largely cancelled out (e.g., signal waves are cancelled as signal is received through each opposite hole/slot of each hole/slot pair). In some embodiments, pairs of holes/slots602,604, and606are sealed with an acoustically transmissive liquid blocking material (e.g., material218ofFIG. 2AandFIG. 3B).

The example container cap shape of fill level sensors (e.g., sensor200) shown in the Figures are merely illustrative. One or more of the internal components shown inFIGS. 2-6may be configured and included similarly in different types of container covers/caps.FIGS. 7A-7Cshow various container covers that may be similarly configured to include one or more of the components shown in other figures.

The examples shown in the figures do not necessarily show every component of the embodiments shown. The figures have been simplified to illustrate the embodiments clearly. Other components not shown may be included in the embodiments. Any of the components shown in the figures may be optional. The figures have not been drawn to absolute and/or relative scale. The components shown may be of any relative or absolute dimension.