Apparatus and method for bubble detection in fluid flow

Abstract

A bubble detection device is provided. For example, a bubble detection device includes a light source, a light sensor, and one or more processors. The light source is adapted to be positioned to irradiate light through a tube through which a fluid flows. The light sensor is adapted to be positioned on an opposite side of the tube from the light source and to receive light transmitted through the tube from the light source. The processor (i) detects a first motion across the light sensor corresponding to a leading edge of a bubble in the fluid, (ii) detects a second motion across the light sensor corresponding to a trailing edge of the bubble in the fluid, and (iii) calculates a length of the bubble based on (a) a velocity of the bubble and (b) a time between the detection of the first motion and the detection of the second motion.

Description

Technical Field

[0001] Embodiments of the present disclosure relate generally to imaging systems, and more particularly to imaging systems for bubble detection. Background Art

[0002] In infusion pumps, drug delivery devices, etc., disruptions in fluid flow and bubbles in fluid delivery tubing can be harmful to the patient's health. Similarly, in industrial applications, disruptions in fluid flow to industrial equipment (such as mixers, separators, etc.) can disrupt the industrial process and potentially damage the industrial equipment.

[0003] It is known to use bubble detection devices to detect bubbles and ruptures in such fluid flows. However, such bubble detection devices are plagued by technical challenges and limitations. Through effort, ingenuity, and innovation, solutions have been developed, including in the embodiments of the present disclosure, to address many of these identified problems, many examples of which are described in detail herein. Summary of the invention

[0004] Various embodiments described herein relate to bubble detection devices and associated methods of detecting bubbles in a fluid flowing through a tube.

[0005] According to various embodiments of the present disclosure, a bubble detection device is provided. In some embodiments, the bubble detection device includes a light source, a light sensor, and one or more processors. The light source is suitable for being positioned to irradiate light through a tube through which a fluid flows. The light sensor is suitable for being positioned on a side of the tube opposite to the light source, and is suitable for receiving light from the light source that is transmitted through the tube. The one or more processors (i) detect a first movement across the light sensor, the first movement corresponding to the leading edge of a bubble in the fluid; (ii) detect a second movement across the light sensor, the second movement corresponding to the trailing edge of the bubble in the fluid; and (iii) calculate the length of the bubble based on (a) the velocity of the bubble and (b) the time between the detection of the first movement and the detection of the second movement.

[0006] In some embodiments, light is received by a light sensor and processed by one or more processors at a frame refresh rate.

[0007] In some embodiments, the one or more processors calculate the velocity of the bubble based on the amount of movement of the bubble across the light sensor in a frame multiplied by the frame refresh rate.

[0008] In some embodiments, one or more processors calculate the velocity of the bubble based on: (1) the amount of movement detected across the leading edge of the light sensor in the first motion multiplied by the frame refresh rate, (2) the amount of movement detected across the trailing edge of the light sensor in the second motion multiplied by the frame refresh rate, or (3) the average of the amount of movement detected across the leading edge of the light sensor in the first motion multiplied by the frame refresh rate and the amount of movement detected across the trailing edge of the light sensor in the second motion multiplied by the frame refresh rate.

[0009] In some embodiments, the first motion is represented by an X-axis motion vector and / or a Y-axis motion vector.

[0010] In some embodiments, one or more processors detect reverse flow of the fluid based on a negative value of the X-axis motion vector and / or a negative value of the Y-axis motion vector.

[0011] In some embodiments, one or more processors start a timer when a first motion is detected and stop the timer when a second motion is detected.

[0012] In some embodiments, one or more processors calculate an estimate of the size of the bubble based on 0.5*(amount of movement detected across the leading edge of the light sensor in the first motion + amount of movement detected across the trailing edge of the light sensor in the second motion)*length of the bubble.

[0013] In some embodiments, the one or more processors determine whether a break in the fluid flow has occurred by determining whether the bubble length is greater than a predetermined multiple of the diameter of the tube.

[0014] In some embodiments, the one or more processors determine whether a bubble is classified as a small bubble by determining whether the bubble length is less than a predetermined fraction of the diameter of the tube.

[0015] According to various embodiments of the present disclosure, a method for detecting bubbles in a fluid flowing through a tube is provided. In some embodiments, the method includes illuminating light from a light source positioned to radiate light through the tube; receiving light from the light source transmitted through the tube by a light sensor positioned on a side of the tube opposite to the light source; detecting a first movement across the light sensor by one or more processors, the first movement corresponding to a leading edge of a bubble in the fluid; detecting a second movement across the light sensor by one or more processors, the second movement corresponding to a trailing edge of a bubble in the fluid; and calculating a length of the bubble by one or more processors based on (a) a velocity of the bubble and (b) a time between detection of the first movement and detection of the second movement.

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

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

[0018] Figure 1 is a perspective view of an exemplary bubble detection device according to an exemplary embodiment of the present disclosure;

[0019] Figure 2 yes Figure 1 A simplified cross-sectional view of a portion of an exemplary bubble detection device of ;

[0020] Figure 3 is a block diagram of an exemplary bubble detection device according to an exemplary embodiment of the present disclosure;

[0021] Figure 4A , Figure 4B and Figure 4C Exemplary detection of typical bubbles, small bubbles, and bursts in fluid flow are shown, respectively; and

[0022] Figure 5A and Figure 5B is a flow chart illustrating an exemplary method of detecting bubbles in a fluid flowing through a tube according to an exemplary embodiment of the present disclosure. DETAILED DESCRIPTION

[0023] Some embodiments of the present disclosure will be described more fully below with reference to the accompanying drawings, which illustrate some, but not all, embodiments of the present disclosure. In fact, these disclosures may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that the present disclosure satisfies applicable legal requirements. Throughout the content, similar reference numerals refer to similar elements.

[0024] As used herein, terms such as "front," "rear," "top," "bottom," "left," "right," and the like are used for illustrative purposes in the examples provided below to describe the relative positions of certain components or portions of components. Additionally, as will be apparent to one of ordinary skill in the art from this disclosure, the terms "substantially" and "approximately" indicate that the referenced element or associated description is accurate within an applicable engineering tolerance.

[0025] As used herein, the term "comprising" means including but not limited to, and should be interpreted in the manner commonly used in the patent context. It should be understood that the use of broad terms such as "comprising," "including," and "having" provides support for narrower terms such as "consisting of," "consisting essentially of," and "consisting essentially of."

[0026] The phrases "in one embodiment," "according to one embodiment," "in some embodiments," and the like generally mean that the particular feature, structure, or characteristic following the phrase may be included in at least one embodiment of the present disclosure, and may be included in more than one embodiment of the present disclosure (importantly, such phrases are not necessarily referring to the same embodiment).

[0027] Phrases such as "in one example," "according to one example," "in some examples," and the like generally mean that a particular feature, structure, or characteristic following the phrase may be included in at least one example of the present disclosure, and may be included in more than one example of the present disclosure (importantly, such phrases do not necessarily refer to the same example).

[0028] If the specification states that a component or feature "may", "can", "could", "should", "will", "preferably", "likely", "usually", "optionally", "for example", "as an example", "in some examples", "often" or "might" (or other such language) be included or have a property, the specific component or feature is not required to be included or have that property. Such components or features may be optionally included in some examples, or may be excluded.

[0029] The word “example” or “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any implementation described herein as “example” or “exemplary” is not necessarily to be construed as preferred or advantageous over other implementations.

[0030] The terms “electrically coupled,” “electrically coupled,” “in communication with,” “in electronic communication with,” or “connected” in this disclosure refer to two or more elements or components that are connected by wired means and / or wireless means such that signals, voltage / current, data and / or information can be transmitted to and / or received from these elements or components.

[0031] The term "component" may refer to an article, device, or apparatus that may include one or more surfaces, parts, layers, and / or elements. For example, an exemplary component may include one or more substrates that may provide one or more underlying layers for the component, and may include one or more elements that form part of atop a substrate and / or one or more elements that may be disposed on top of a substrate. In the present disclosure, the term "element" may refer to an article, device, or apparatus that may provide one or more functions.

[0032] As used herein, the term "bubble" refers to a small ball of gaseous material in a fluid. As used herein, the term "fluid rupture" refers to a void in a fluid that is several times larger than the diameter of a tube.

[0033] There are many different devices for delivering fluids, such as via one or more pumps and one or more sections of tubing. Some of these devices are used in the medical field. For example, an infusion pump delivers intravenous (IV) fluids, often mixed with one or more liquid medications, to a patient's bloodstream via an IV tube and IV catheter. If air bubbles are inadvertently introduced into the IV tube, this may endanger the patient. Therefore, it is important to detect these bubbles so that appropriate corrective measures can be taken.

[0034] As another example, a hemodialysis machine pumps a patient's blood through a filter, which removes waste products from the blood, usually via a dialysate, and then pumps the blood back to the patient. It is important to detect bubbles in the blood flowing through the tube. It is also important to detect the direction of blood flow to ensure that the blood is flowing normally through the hemodialysis machine.

[0035] Various embodiments of the present disclosure overcome the above-mentioned technical challenges and difficulties, and provide various technical improvements and advantages. For example, various embodiments of the present disclosure provide exemplary devices for detecting bubbles in a fluid flowing through a tube. Various embodiments of the present disclosure provide exemplary devices for detecting ruptures in a fluid flowing through a tube. Various embodiments of the present disclosure provide exemplary devices for detecting the direction of a fluid flowing through a tube. Various embodiments of the present disclosure provide exemplary devices and methods for detecting bubbles in a fluid flowing through a tube, which are not based on the amount of light attenuated by the fluid or bubbles, but instead utilize optical motion detection methods.

[0036] In some embodiments, the bubble detection device includes an optical tracking sensor. This optical tracking sensor has an array of individual sensing elements, such as arranged in 64x64 pixels or 128x128 pixels. Each pixel of this optical tracking sensor has a size or spacing (e.g., 50 microns). In some embodiments, this optical tracking sensor has a configurable frame refresh rate. In some embodiments, the frame refresh rate can be set to, for example, 1000 Hertz (Hz) or 2000 Hz. In some embodiments, a higher frame refresh rate is generally better than a lower frame refresh rate. In some embodiments, an optical tracking sensor is used in this bubble detection device, such as the PAA5100JE-Q from PixArt Imaging Inc. or the ADNS 3050-M from Avago Technologies Limited.

[0037] In some embodiments, the bubble detection device includes an optical tracking sensor, which receives light transmitted through the tube via a light source positioned on a side of the tube opposite to the optical tracking sensor. In some embodiments, the light source includes a light emitting diode (LED). In some embodiments, the LED is an infrared LED. In some embodiments, the LED is an infrared LED with a wavelength of about 820 nanometers (nm) to 980 nanometers (nm). In some embodiments, the LED is an infrared LED with a wavelength of about 950 nanometers to 980 nanometers. In some embodiments, the LED is a visible light LED, which can be suitable for industrial applications. In some embodiments, the LED is a visible light LED with a wavelength of about 450nm to 525nm, 550nm to 675nm, or 700nm to 800nm. In some embodiments, the wavelength of the emitted light is selected so that the tube is transparent to light. In some embodiments, the wavelength of the emitted light is selected to be used with a tube constructed of polyvinyl chloride (PVC), polyethylene, thermoplastic elastomer (TPE), nylon, or silicone.

[0038] In some embodiments, the bubble detection device detects bubbles in a tube having a diameter of about 3 mm to about 25 mm. In some embodiments, the bubble detection device receives a portion of the tube in a groove. In some embodiments, the bubble detection device detects bubbles in a tube through which fluid flows at a typical flow rate for delivering IV fluids, such as about 0.5 milliliters per hour to about 1 liter per hour.

[0039] In some embodiments, the bubble detection device detects the leading edge (LE) of a bubble or fluid rupture and / or the trailing edge (TE) of a bubble or fluid rupture. The process of detecting a bubble and the process of detecting a fluid rupture are substantially the same, except as noted herein. Therefore, for simplicity, this disclosure will generally omit references to fluid rupture unless it is necessary to distinguish it from the detection of a bubble.

[0040] In some embodiments, the optical tracking sensor and associated processor detect motion only when the leading edge of a bubble or fluid ruptures across the optical tracking sensor and when the trailing edge of the bubble or fluid ruptures across the optical tracking sensor. In some embodiments, the optical tracking sensor and associated processor detect no motion when no bubble passes through the optical tracking sensor, when the leading edge travels across the optical tracking sensor except for the first instance at which motion is detected, or when the trailing edge travels across the optical tracking sensor except for the first instance at which motion is detected. In other words, there is a single detection of motion (a "flicker") when the leading edge begins to pass the optical tracking sensor, and a single detection of motion (another "flicker") when the trailing edge begins to pass the optical tracking sensor, and no motion is detected at any other time.

[0041] In some embodiments, when the leading edge of the bubble is detected, the bubble detection device receives an X-axis motion vector and / or a Y-axis motion vector. In some embodiments, when the trailing edge of the bubble is detected, the bubble detection device receives another X-axis motion vector and / or a Y-axis motion vector.

[0042] In some embodiments, the X-axis motion vector (of the leading edge and / or trailing edge) and / or the Y-axis motion vector may be negative. In some embodiments, when the X-axis motion vector or the Y-axis motion vector is negative, this indicates that the fluid is flowing in the opposite direction.

[0043] In some embodiments, the motion vector is used to calculate the movement of the leading edge (referred to herein as "motion (LE)"). In some embodiments, the motion vector is used to calculate the movement of the trailing edge (referred to herein as "motion (TE)"). In some embodiments, the following equation is used to calculate the movement of the leading edge and the movement of the trailing edge: Movement = square root ((dx n ) 2 +(dy n ) 2 ), where dx n are the X-axis motion vectors of the leading or trailing edge, respectively, and dy n are the Y-axis motion vectors of the leading or trailing edge, respectively.

[0044] In some embodiments, the movement of the leading edge is used to calculate the net movement of the leading edge (referred to herein as "net movement (LE)"). In some embodiments, the movement of the trailing edge is used to calculate the net movement of the trailing edge (referred to herein as "net movement (TE)"). The net movement converts the motion vector into a measurement result based on the pixel spacing of the optical tracking sensor. In some embodiments, the net movement of the leading edge is calculated using the following equation: Net movement (LE) = movement (LE) * pixel spacing. In some embodiments, the net movement of the trailing edge is calculated using the following equation: Net movement (TE) = movement (TE) * pixel spacing.

[0045] In some embodiments, motion may be detected due to the presence of very small bubbles and / or very small contaminants that can be safely ignored. For example, in some embodiments, the smallest bubble of concern is 100 microns or 0.1 mm, and any bubble smaller than 100 microns may be ignored. Thus, in some embodiments, the net movement may be compared to a predetermined threshold to determine whether the detected motion is due to something small enough to be ignored. In some embodiments, the predetermined threshold is based on a multiple of the pixel spacing. For example, the predetermined threshold may be set to ten times the pixel spacing. Thus, in some embodiments, the bubble detection device determines whether the net movement of the leading edge is greater than 10*pixel spacing, and if not, ignores the detected motion.

[0046] In some embodiments, the speed of the detected bubble is determined (referred to as "bubble_speed"). As described below, this speed is used to determine the bubble length. In some embodiments, the speed of the bubble (in millimeters per second (mm / sec)) is based on the speed of the leading edge (referred to herein as "speed (LE)"), calculated using the following equation: speed (LE) = (movement (LE) * frame_refresh_rate) / 1000. In some embodiments, the speed of the bubble (in mm / sec) is based on the speed of the trailing edge (referred to herein as "speed (TE)"), calculated using the following equation: speed (TE) = (movement (TE) * frame_refresh_rate) / 1000. In some embodiments, the speed of the bubble is based on averaging the speed of the leading edge and the speed of the trailing edge.

[0047] In some embodiments, the timer is started when the leading edge of the bubble is detected, and the timer is stopped when the trailing edge of the bubble is detected. In some embodiments, the length of the bubble (in mm) is calculated using the following equation: Bubble_Length = Bubble_Speed ​​* Timer_Value.

[0048] In some embodiments, a break in the fluid flow is identified by determining whether the bubble length is greater than a predetermined multiple of the diameter of the tube. For example, if the bubble length is greater than 20 times the diameter of the tube, the bubble can be considered a fluid break.

[0049] In some embodiments, "tiny" bubbles are identified by determining whether the bubble length is less than a predetermined fraction of the diameter of the tube. For example, if the bubble length is less than one-tenth of the diameter of the tube, the bubble can be considered a tiny bubble. In some embodiments, tiny bubbles are ignored.

[0050] An estimate of the overall size of a detected bubble may be calculated using the following equation: bubble_size = 0.5*(net movement (LE) + net movement (TE))* bubble_length.

[0051] Reference now Figure 1 , provides a perspective view of an exemplary bubble detection device according to an exemplary embodiment of the present disclosure. Figure 1 As shown, in some embodiments, the bubble detection device 100 includes a housing 102 having a slot 104 defined therein for receiving a portion of a tube, such as an IV tube 106. In some embodiments, the housing 102 includes a rectangular prism, as shown, although any suitable shape can be used. In some embodiments, the tube 106 fits tightly within the slot 104, with sufficient tightness that the tube 106 is retained within the slot 104, but preferably without significantly compressing the tube 106. In some embodiments, the housing 102 is constructed of any suitable material, such as any suitable plastic. In some embodiments, the housing 102 houses and protects internal components as described below.

[0052] In some embodiments, the bubble detection device 100 includes a power cord 108 for receiving power from an AC outlet. In other embodiments, the bubble detection device 100 can be powered by batteries, where one or more batteries are housed in the housing 102.

[0053] In some embodiments, the bubble detection device 100 includes a mounting mechanism (not shown) for mounting the bubble detection device 100 in a convenient location, such as on the side of an IV pump.

[0054] In some embodiments, the bubble detection device 100 includes an indicator light or the like to indicate whether bubbles have been detected. In the illustrated embodiment, the indicator light 110 includes a green light indicating that no bubbles have been detected and a red light indicating that bubbles have been detected. In some embodiments, the bubble detection device 100 includes an indicator light or the like (not shown) to indicate whether reverse flow of fluid has been detected.

[0055] In some embodiments, the bubble detection device 100 includes markings indicating the correct placement of the tubes relative to the fluid source and the fluid destination. In the illustrated embodiment, the markings 112 indicate the correct placement of the tubes relative to the IV pump (i.e., the fluid source) and the patient (i.e., the fluid destination).

[0056] Reference now Figure 2 , a simplified cross-sectional view of a portion of an exemplary bubble detection device 100 is shown. Figure 2 Some of the internal structures and components within the housing 102 and forming the slot 104 are shown. Figure 2 As shown, the optical tracking sensor 204 is positioned on a circuit board 206 that is mounted on the internal structure 202 of the bubble detection device 100. As described above, the optical tracking sensor 204 includes an array of individual sensing elements / pixels (e.g., 64x64). The circuit board 206 includes one or more additional electronic components to facilitate the operation of the optical tracking sensor 204. In some embodiments, the circuit board 206 includes a processor that controls the operation of the optical tracking sensor 204, which is integrated with a processor that controls the overall operation of the bubble detection device 100 ( Figure 2 In some embodiments, a single processor controls the operation of the optical tracking sensor and the overall operation of the bubble detection device.

[0057] LED 208 is mounted to inner structure 202 opposite optical tracking sensor 204. When tube 106 is inserted into slot 104, tube 106 is positioned between optical tracking sensor 204 and LED 208, as shown in FIG. Figure 2 As shown, light emitted from LED 208 is transmitted through tube 106 and received by optical tracking sensor 204 and processed as described herein. Figure 2 As shown, the tube 106 contains a fluid 210 flowing therethrough. The fluid may contain one or more bubbles 212 to be detected.

[0058] Reference now Figure 3 , a block diagram of an exemplary bubble detection device 300 according to various embodiments of the present disclosure is provided. Figure 3 As shown, in some embodiments, the bubble detection device 300 includes a processor or processing circuit 302, a memory circuit 304, an input / output circuit 306, a communication circuit 308, a motion sensor 310, a motion processor or processing circuit 312, and an LED 314. In some embodiments, the bubble detection device 300 is configured to perform and carry out the operations described herein.

[0059] Although these components are described with respect to functional limitations, it should be understood that at least some of the specific implementations necessarily include the use of specific computing hardware. It should also be understood that in some embodiments, certain components described herein include similar or common hardware. For example, in some embodiments, two sets of circuits utilize the use of the same processor, memory, circuits, etc. to perform their associated functions, so that each set of circuits does not require duplicate hardware.

[0060] The processing circuit 302 may be embodied in a variety of different ways. In various embodiments, the use of the term "processor" or "processing circuit" should be understood to include a single core processor, a multi-core processor, multiple processors internal to the bubble detection device 300, and / or one or more remote or "cloud" processors external to the bubble detection device 300. In some exemplary embodiments, the processing circuit 302 may include one or more processing devices configured to execute independently. Alternatively or additionally, the processing circuit 302 may include one or more processors configured in series via a bus to enable independent execution of operations, instructions, pipelining, and / or multithreading.

[0061] In an exemplary embodiment, the processing circuit 302 may be configured to execute instructions stored in the memory circuit 304 or otherwise accessible by the processor. Alternatively or additionally, the processing circuit 302 may be configured to perform hard-coded functions. Therefore, whether configured by hardware methods or software methods, or by a combination thereof, the processing circuit 302 may represent an entity (e.g., physically embodied in circuit form) that is capable of performing operations according to the embodiments of the present disclosure while being configured accordingly. Alternatively or additionally, the processing circuit 302 may be embodied as an executor of software instructions, and these instructions may specifically configure the processing circuit 302 to perform various algorithms embodied in one or more operations described herein when executing such instructions. In some embodiments, the processing circuit 302 includes hardware, software, firmware, and / or a combination thereof that performs one or more operations described herein.

[0062] In some embodiments, the processing circuit 302 (and / or a co-processor or any other processing circuit that assists or is otherwise associated with the processor) communicates with the memory circuit 304 via a bus for passing information between components of the bubble detection device 300.

[0063] The memory or memory circuit 304 may be non-transitory and may include, for example, one or more volatile and / or non-volatile memories. In some embodiments, the memory circuit 304 includes or embodies an electronic storage device (e.g., a computer-readable storage medium). In some embodiments, the memory circuit 304 is configured to store information, data, content, applications, instructions, etc. for enabling the bubble detection device 300 to perform various operations and / or functions according to exemplary embodiments of the present disclosure.

[0064] Input / output circuit 306 may be included in bubble detection device 300. In some embodiments, input / output circuit 306 may provide output to a user and / or receive input from a user. Input / output circuit 306 may communicate with processing circuit 302 to provide such functionality. Input / output circuit 306 may include one or more user interfaces. In some embodiments, the user interface may include a display including an interface presented as a web user interface, an application user interface, a user device, a backend system. In some embodiments, input / output circuit 306 also includes a keyboard, a mouse, a joystick, a touch screen, a touch area, a soft key, a microphone, a speaker, or other input / output mechanism. Processing circuit 302 and / or input / output circuit 306 may be configured to control one or more operations and / or functions of one or more user interface elements by computer program instructions (e.g., software and / or firmware) stored on a processor-accessible memory (e.g., memory circuit 304, etc.). In some embodiments, input / output circuit 306 includes or utilizes a user-oriented application to provide input / output functionality to a computing device and / or other display associated with a user. In some embodiments, for example, the input / output circuit 306 includes an indicator light 110 .

[0065] The communication circuit 308 may be included in the bubble detection device 300. The communication circuit 308 may include any device, such as a device or circuit embodied in hardware or a combination of hardware and software, which is configured to receive and / or transmit data from / to a network and / or any other device, circuit or module in communication with the bubble detection device 300. In some embodiments, the communication circuit 308 includes, for example, a network interface for enabling communication with a wired or wireless communication network. Additionally or alternatively, the communication circuit 308 may include one or more network interface cards, antennas, buses, switches, routers, modems and supporting hardware, firmware and / or software, or any other device suitable for enabling communication via one or more communication networks. In some embodiments, the communication circuit 308 may include circuits for interacting with antennas and / or other hardware or software to cause the transmission of signals via the antennas and / or the reception of signals received via the antennas. In some embodiments, the communication circuit 308 enables the transmission and / or reception of data to and / or from a user device, one or more sensors and / or other external computing devices in communication with the bubble detection device 300. In some embodiments, the communication circuit 308 transmits information related to the bubble detection (wired or wirelessly) to the IV pump so that the IV pump stops pumping when bubbles are detected.

[0066] Along with the motion processor 312, the motion sensor 310 may be included in the bubble detection device 300. As described above, the motion sensor 310 includes an optical tracking sensor having a single array of sensing elements. Similar to the processing circuit 302, the motion processor 312 may be embodied in a number of different ways, including but not limited to a single core processor, a multi-core processor, or multiple processors within the bubble detection device 300. In some embodiments, such as Figure 3 In some embodiments, the motion processor 312 is separated from the processing circuit 302 because the bubble detection device 300 can use an off-the-shelf optical navigation system (e.g., PAA5100JE-Q from PixArt Imaging Inc. or ADNS 3050-M from Avago Technologies Limited) that includes both an optical tracking sensor and a motion processor. In some embodiments (not shown), the functionality of the motion processor is included in the processing circuit 302, and a separate motion processor is omitted.

[0067] LED 314 can be included in bubble detection device 300. LED 314 can be any suitable LED or other light source. In some embodiments, the LED is an infrared LED having a wavelength of about 950 nanometers to 980 nanometers.

[0068] In some embodiments, two or more of the groups of circuits 302 to 308 are combinable. Alternatively or additionally, one or more of the groups of circuits 302 to 308 perform some or all of the operations and / or functions described herein as being associated with another circuit. In some embodiments, two or more of the groups of circuits 302 to 308 are combined into a single module embodied in the form of hardware, software, firmware, and / or a combination thereof.

[0069] Although the above description provides an exemplary bubble detection device 300, it should be noted that the scope of the present disclosure is not limited to the above description. In some examples, the exemplary bubble detection device 300 according to the present disclosure can be in other forms. In some examples, the exemplary bubble detection device 300 may include one or more additional and / or alternative components, and / or may be used in conjunction with Figure 3 The shown structures are different.

[0070] As described above, a single flickering motion is detected when the leading edge is first detected traveling across the optical tracking sensor. Similarly, a single flickering motion is detected when the trailing edge is first detected traveling across the optical tracking sensor. FIG. 4A to FIG. 4C , showing exemplary detection of typical bubbles, small bubbles, and bursts in fluid flow, respectively. FIG. 4A to FIG. 4C In the graph, the X-axis is time, and the Y-axis is the amplitude of the detected motion.

[0071] Figure 4A An example detection of a typical (ie, not tiny and not bursting in the fluid) bubble 412A in a fluid 410 flowing through a tube 406 positioned between an optical tracking sensor 404 and a light source 408 (eg, an LED) is shown. Figure 4A , first motion detection indication 414A corresponds to detection of the leading edge of bubble 412A, and second motion detection indication 416A corresponds to detection of the trailing edge of bubble 412A. The distance between first motion detection indication 414A and second motion detection indication 416A is the amount of time between detection of the leading edge and detection of the trailing edge (which is captured by the timer referenced above).

[0072] Figure 4B 4 shows an exemplary detection of a tiny (e.g., having a length less than a predetermined fraction of the diameter of the tube) bubble 412B in a fluid 410 flowing through a tube 406 positioned between an optical tracking sensor 404 and a light source 408 (e.g., an LED). Figure 4B , first motion detection indication 414B corresponds to detection of the leading edge of bubble 412B, and second motion detection indication 416B corresponds to detection of the trailing edge of bubble 412B. The distance between first motion detection indication 414B and second motion detection indication 416B is the amount of time between detection of the leading edge and detection of the trailing edge (which is captured by the timer referenced above).

[0073] Figure 4C An exemplary detection of a fluid rupture (i.e., a void in the fluid that is several times larger than the diameter of the tube) bubble 412C in a fluid 410 flowing through a tube 406 positioned between an optical tracking sensor 404 and a light source 408 (e.g., an LED) is shown. Figure 4C , first motion detection indication 414C corresponds to detection of the leading edge of bubble 412C, and second motion detection indication 416C corresponds to detection of the trailing edge of bubble 412C. The distance between first motion detection indication 414C and second motion detection indication 416C is the amount of time between detection of the leading edge and detection of the trailing edge (which is captured by the timer referenced above).

[0074] Now refer to Figure 5A and Figure 5B , which provide flowcharts showing exemplary steps, processes, procedures and / or operations according to various embodiments of the present disclosure. The various methods described herein (including, for example, Figure 5A and Figure 5B The method shown) can provide various technical benefits and improvements.

[0075] Reference now Figure 5A and Figure 5B , an exemplary method 500 is shown. In some embodiments, the exemplary method includes a method for bubble detection in fluid flow. At step / operation 502, a processor (such as but not limited to the above combined Figure 3 The processing circuit 302 and / or the motion processor 312 of the exemplary bubble detection device 300 receives a motion vector corresponding to the detection of the motion within the fluid flowing in the tube. As described above, the motion vector may include an X-axis motion vector (which may be represented as dx n ) and / or the Y-axis motion vector (which can be represented by dy n ).

[0076] At step / operation 504, a processor (such as but not limited to the above combination Figure 3 The processing circuit 302 and / or the motion processor 312 of the exemplary bubble detection device 300 determines whether either or both of the motion vectors are non-zero, thereby indicating detection of motion.

[0077] At step / operation 506, a processor (such as but not limited to the above combination Figure 3 The processing circuit 302 and / or the motion processor 312 of the exemplary bubble detection device 300 described herein determines whether a leading edge (LE) flag has been previously set to 1. If the LE flag has not been previously set to 1, then in some embodiments, this would indicate that a leading edge has not been detected (at least not in this cycle). If the LE flag has been previously set to 1, then in some embodiments, this would indicate that a leading edge has been detected (at least in this cycle).

[0078] If it is determined at step / operation 506 that the LE flag was not previously set to 1, then method 500 proceeds to step / operation 508. In some embodiments, since the LE flag was not previously set to 1 and motion was detected at step / operation 504, this indicates that the motion detected at step / operation 504 is the leading edge of a bubble or fluid collapse. At step / operation 508, a processor (such as, but not limited to, the above combined Figure 3 The processing circuit 302 and / or the motion processor 312 of the exemplary bubble detection device 300 sets the LE flag to 1 and starts the bubble timer.

[0079] After step / operation 508, method 500 proceeds to step / operation 512. At step / operation 512, a processor (such as but not limited to the above combination Figure 3 The processing circuit 302 and / or the motion processor 312 of the exemplary bubble detection device 300 described above calculates the LE movement and the LE net movement. As described above, in some embodiments, the movement of the leading edge is calculated using the following equation: Movement (LE) = square root ((dxn ) 2 +(dy n ) 2 ), where dx n is the X-axis motion vector of the leading edge, and dy n is the Y-axis motion vector of the leading edge. Also as described above, in some embodiments, the net movement of the leading edge is calculated using the following equation: Net Movement (LE) = Movement (LE) * Pixel Pitch.

[0080] At step / operation 514, a processor (such as but not limited to the above combination Figure 3 The processing circuit 302 and / or the motion processor 312 of the exemplary bubble detection device 300 determines whether the net movement of the leading edge is greater than a predetermined threshold. As described above, in some embodiments, the predetermined threshold is based on a multiple of the pixel pitch.

[0081] If it is determined at step / operation 514 that the net movement of the leading edge is not greater than a predetermined threshold, in some embodiments, this means that anything detected is very small and can be ignored. Method 500 proceeds to step / operation 515, where a processor (such as, but not limited to, the above combination) Figure 3 The processing circuit 302 and / or the motion processor 312 of the exemplary bubble detection device 300 resets the LE flag to 0, and the method 500 returns to step / operation 502 to await the detection of the next bubble or fluid rupture.

[0082] If it is determined at step / operation 514 that the net movement of the leading edge is greater than a predetermined threshold, then in some embodiments, this means that the detected motion may be a bubble, and method 500 proceeds to step / operation 516. At step / operation 516, a processor (such as, but not limited to, the above combined Figure 3 The processing circuit 302 and / or the motion processor 312 of the exemplary bubble detection device 300 sets the bubble detection flag to “yes”.

[0083] At step / operation 518, a processor (such as but not limited to the above combination Figure 3 The processing circuit 302 and / or the motion processor 312 of the exemplary bubble detection device 300 determines whether any of the motion vectors is negative.

[0084] If it is determined at step / operation 518 that one or both of the motion vectors are negative, in some embodiments, this means that the fluid is flowing in the opposite direction to the intended direction (i.e., in reverse), and the method 500 proceeds to step / operation 520. At step / operation 520, a processor (such as, but not limited to, the above combined Figure 3The processing circuit 302 and / or the motion processor 312 of the exemplary bubble detection device 300 sets the bubble direction flag to "reverse flow".

[0085] If it is determined at step / operation 518 that none of the motion vectors are negative, in some embodiments, this means that the fluid is flowing in the expected direction, and method 500 proceeds to step / operation 522. At step / operation 522, a processor (such as, but not limited to, the above combined Figure 3 The processing circuit 302 and / or the motion processor 312 of the exemplary bubble detection device 300 sets the bubble direction flag to "flow in line".

[0086] At step / operation 524, a processor (such as but not limited to the above combination Figure 3 The processing circuit 302 and / or the motion processor 312 of the exemplary bubble detection device 300 described herein calculates the leading edge velocity. As described above, in some embodiments, the leading edge velocity is calculated using the following equation: velocity (LE) = (movement (LE) * frame_refresh_rate) / 1000.

[0087] In some embodiments, the method 500 then proceeds to step / operation 502 to await detection of a trailing edge, during which the bubble timer is running. When a subsequent motion vector is received at step / operation 502 and movement is detected at step / operation 504, since the LE flag was previously set to 1 at step / operation 508, it will be determined at step / operation 506 that the LE flag = 1, and the method 500 proceeds to step / operation 510. Since the LE flag was previously set to 1, in some embodiments, it is known that the subsequently detected motion is from the trailing edge (TE) of the same bubble.

[0088] At step / operation 510, a processor (such as but not limited to the above combination Figure 3 The processing circuit 302 and / or the motion processor 312 of the exemplary bubble detection device 300) sets the LE flag to 0, stops the bubble timer, and records the value of the bubble timer. The method 500 then proceeds to Figure 5B Step / operation 526.

[0089] At step / operation 526, a processor (such as but not limited to the above combination Figure 3 The processing circuit 302 and / or the motion processor 312 of the exemplary bubble detection device 300 described above calculates the TE movement and the TE net movement. As described above, in some embodiments, the movement of the trailing edge is calculated using the following equation: Movement (TE) = square root ((dx n ) 2 +(dy n ) 2), where dx n is the X-axis motion vector of the trailing edge, and dy n is the Y-axis motion vector of the trailing edge. Also as described above, in some embodiments, the net movement of the trailing edge is calculated using the following equation: Net Movement (TE) = Movement (TE) * Pixel Pitch.

[0090] At step / operation 528, a processor (such as but not limited to the above combination Figure 3 The processing circuit 302 and / or motion processor 312 of the exemplary bubble detection device 300 described above calculates the trailing edge velocity. As described above, in some embodiments, the velocity of the trailing edge is calculated using the following equation: velocity (TE) = movement (TE) * frame_refresh_rate) / 1000. At step / operation 528, a processor (such as, but not limited to, the above combined Figure 3 The processing circuit 302 and / or the motion processor 312 of the exemplary bubble detection device 300 calculates the velocity of the bubble. As described above, in some embodiments, the velocity of the bubble is based on averaging the velocity of the leading edge and the velocity of the trailing edge.

[0091] At step / operation 530, a processor (such as but not limited to the above combination Figure 3 The processing circuit 302 and / or the motion processor 312 of the exemplary bubble detection device 300 calculates the length of the detected bubble. As described above, in some embodiments, the length of the bubble is calculated using the following equation: bubble_length=bubble_speed*timer_value.

[0092] At step / operation 532, a processor (such as but not limited to the above combination Figure 3 The processing circuit 302 and / or the motion processor 312 of the exemplary bubble detection device 300 described herein calculates an estimate of the size of the detected bubble. As described above, in some embodiments, the following equation can be used to calculate an estimate of the overall size of the detected bubble: bubble_size=0.5*(net movement (LE)+net movement (TE))*bubble_length.

[0093] At step / operation 534, a processor (such as but not limited to the above combination Figure 3 The processing circuit 302 and / or the motion processor 312 of the exemplary bubble detection device 300 described above determines whether the bubble length is greater than a predetermined upper threshold. As described above, in some embodiments, a break in the fluid flow is identified by determining whether the bubble length is greater than a predetermined multiple of the diameter of the tube. For example, if the bubble length is greater than 20 times the diameter of the tube, the bubble can be considered a fluid break. Therefore, in some embodiments, it is determined at step / operation 534 whether the bubble length is greater than 20 times the diameter of the tube.

[0094] If it is determined at step / operation 534 that the bubble length is greater than the predetermined upper threshold, the method 500 proceeds to step / operation 536 and declares a “fluid rupture.” The method 500 then returns to step / operation 502 to await detection of the next bubble or fluid rupture.

[0095] If it is determined at step / operation 534 that the bubble length is not greater than the predetermined upper threshold, the method 500 proceeds to step / operation 538 .

[0096] At step / operation 538, a processor (such as but not limited to the above combination Figure 3 The processing circuit 302 and / or the motion processor 312 of the exemplary bubble detection device 300 described above determines whether the bubble length is less than a predetermined lower threshold. As described above, in some embodiments, tiny bubbles in the fluid flow are identified by determining whether the bubble length is less than a predetermined fraction of the diameter of the tube. For example, if the bubble length is less than one-tenth of the diameter of the tube, the bubble can be considered a tiny bubble. Therefore, in some embodiments, it is determined at step / operation 538 whether the bubble length is less than one-tenth of the diameter of the tube.

[0097] If it is determined at step / operation 538 that the bubble length is less than the predetermined lower threshold, the method 500 proceeds to step / operation 540 and declares a “micro bubble.” The method 500 then returns to step / operation 502 to await detection of the next bubble or fluid rupture.

[0098] If it is determined at step / operation 538 that the bubble length is not less than the predetermined lower threshold, the method 500 proceeds to step / operation 542 and declares a “typical bubble.” The method 500 then returns to step / operation 502 to await detection of the next bubble or fluid rupture.

[0099] In some embodiments, method 500 is repeated as long as the corresponding fluid delivery device is pumping fluid.

[0100] Despite Figure 5A and Figure 5B 10. Although not shown, in various embodiments of the present disclosure, there may be one or more predetermined actions taken in response to one or more determinations and / or steps / operations of the bubble detection method. For example, in some embodiments, when bubbles are detected, an indicator (such as indicator light 110) may be activated to indicate the presence of bubbles to the user. For another example, in some embodiments, when reverse fluid flow is detected, an alarm may be sounded and / or a signal may be sent to the fluid delivery device to cause the fluid delivery device to stop pumping fluid. For another example, in some embodiments, when a break in the fluid flow is detected, an alarm may be sounded and / or a signal may be sent to the fluid delivery device to cause the fluid delivery device to stop pumping fluid.

[0101] The operations and processes described herein support a combination of means for performing the specified functions and a combination of operations for performing the specified functions. It will be understood that one or more operations and a combination of operations can be implemented by a computer system based on dedicated hardware that performs the specified functions or a combination of dedicated hardware and computer instructions.

[0102] In some example embodiments, some of the operations herein may be modified or further amplified as described below. In addition, in some embodiments, additional optional operations may also be included. It should be understood that each of the modifications, optional additions, or amplifications described herein may be included in the operations herein, either individually or in combination with any other features described herein.

[0103] The foregoing method and process descriptions are provided only as illustrative examples, and are not intended to require or imply that the steps of the various embodiments must be performed in the order presented. As will be appreciated by those skilled in the art, the order of steps in the above-described embodiments may be performed in any order. Words such as "afterwards," "then," "next," and the like are not intended to limit the order of the steps; these words are simply used to guide the reader through the description of the method. In addition, for example, any reference to a claim element in the singular form using the articles "a," "an," or "the" should not be construed as limiting the element to the singular and, in some cases, may be construed in the plural.

[0104] Although various embodiments according to the principles disclosed herein have been shown and described above, modifications may be made thereto by those skilled in the art without departing from the teachings of the present disclosure. The embodiments described herein are representative only and are not intended to be limiting. Many variations, combinations and modifications are possible and are within the scope of the present disclosure. Alternative embodiments obtained by merging, integrating and / or omitting the features of one or more embodiments are also within the scope of the present disclosure. Therefore, the scope of protection is not limited by the description given above, but by the following claims, which include all equivalents of the subject matter of the claims. Each claim is incorporated into the specification as further disclosure, and the claims are embodiments of the present disclosure. In addition, any of the above advantages and features may relate to specific embodiments, but the application of such published claims should not be limited to methods and structures that achieve any or all of the above advantages or have any or all of the above features.

[0105] In addition, the section headings used herein are intended to be consistent with the recommendations of 37 CFR § 1.77 or to provide organizational clues. These headings should not limit or characterize the disclosures set forth in any claims that may be published from this disclosure. For example, the description of the technology in the "background technology" should not be interpreted as an admission that a certain technology is prior art to any disclosure in this disclosure. "Summary of the invention" should also not be considered as a limiting characterization of the disclosure set forth in the published claims. In addition, any reference to the singular "disclosure" or "embodiment" in this disclosure should not be used to prove that there is only one novel point in this disclosure. According to the limitations of multiple claims published from this disclosure, multiple embodiments of the disclosure may be set forth, and such claims accordingly define the disclosures protected by them and their equivalents. In all cases, the scope of these claims should be considered in accordance with the present disclosure on the merits of the claims themselves, and should not be limited by the titles set forth herein.

[0106] Moreover, without departing from the scope of the present disclosure, the systems, subsystems, devices, techniques and methods described and shown in a discrete or separate manner in various embodiments may be combined or integrated with other systems, modules, techniques or methods. Other devices or components shown or discussed as being connected or communicating with each other may be indirectly connected through some intermediate devices or components, whether such connection is made electrically, mechanically or otherwise. Other examples of changes, substitutions and modifications may be determined by those skilled in the art and may be made without departing from the scope disclosed herein.

[0107] Those skilled in the art to which these embodiments belong will think of many modifications and other embodiments of the disclosure set forth herein, which have the benefit of the teachings presented in the foregoing description and the associated drawings. Although the drawings only show certain components of the devices and systems described herein, various other components can be used in combination with the components and structures disclosed herein. Therefore, it should be understood that the present disclosure is not limited to the specific embodiments disclosed, and modifications and other embodiments are intended to be included within the scope of the appended claims. For example, various elements or components may be combined, rearranged or integrated into another system, or certain features may be omitted or not implemented. In addition, the steps in any of the above methods may not necessarily occur in the order depicted in the drawings, and in some cases, one or more of the depicted steps may occur substantially simultaneously, or may involve additional steps. Although specific terms are used herein, they are used only in a general and descriptive sense, not for the purpose of limitation.

Claims

1. A bubble detection device, comprising: a light source adapted to be positioned to shine light through the tube through which the fluid flows; a light sensor adapted to be positioned on a side of the tube opposite the light source and adapted to receive light from the light source transmitted through the tube; and one or more processors that (i) detect a first motion across the light sensor, the first motion corresponding to a leading edge of a bubble in the fluid; (ii) detecting a second motion across the light sensor, the second motion corresponding to a trailing edge of the bubble in the fluid; and (iii) calculating a length of the bubble based on (a) a velocity of the bubble and (b) a time between detection of the first motion and detection of the second motion.

2. The bubble detection apparatus of claim 1 , wherein the light is received by the light sensor and processed by the one or more processors at a frame refresh rate; and Wherein the one or more processors calculate the velocity of the bubble based on an amount of movement of the bubble across the light sensor in a frame multiplied by the frame refresh rate.

3. The bubble detection device of claim 2, wherein the one or more processors calculate the velocity of the bubble based on: (1) the amount of movement across the leading edge of the light sensor in the detected first motion multiplied by the frame refresh rate, (2) the amount of movement across the trailing edge of the light sensor in the detected second motion multiplied by the frame refresh rate, or (3) an average of the amount of movement across the leading edge of the light sensor in the detected first motion multiplied by the frame refresh rate and the amount of movement across the trailing edge of the light sensor in the detected second motion multiplied by the frame refresh rate.

4. The bubble detection device according to claim 1, wherein the first motion is represented by an X-axis motion vector and / or a Y-axis motion vector; and The one or more processors detect reverse flow of the fluid based on a negative value of the X-axis motion vector and / or a negative value of the Y-axis motion vector.

5. The bubble detection apparatus of claim 1 , wherein the one or more processors calculate an estimate of the size of the bubble based on 0.5*(amount of movement across the leading edge of the light sensor in the detected first motion+amount of movement across the trailing edge of the light sensor in the detected second motion)*the length of the bubble.

6. The bubble detection apparatus of claim 1, wherein the one or more processors determine whether a break in the fluid flow has occurred by determining whether the bubble length is greater than a predetermined multiple of the diameter of the tube; and The one or more processors determine whether the bubble is classified as a small bubble by determining whether the bubble length is less than a predetermined fraction of the diameter of the tube.

7. A method of detecting bubbles in a fluid flowing through a tube, the method comprising: shining light from a light source positioned to shine the light through the tube; receiving light from the light source transmitted through the tube via a light sensor positioned on a side of the tube opposite the light source; detecting, by one or more processors, a first motion across the light sensor, the first motion corresponding to a leading edge of a bubble in the fluid; detecting, by the one or more processors, a second movement across the light sensor, the second movement corresponding to a trailing edge of the bubble in the fluid; as well as The length of the bubble is calculated, by the one or more processors, based on (a) a velocity of the bubble and (b) a time between detection of the first motion and detection of the second motion.

8. The method of claim 7, wherein the light is received by the light sensor and processed by the one or more processors at a frame refresh rate; and The method further includes calculating, by the one or more processors, the velocity of the bubble based on an amount of movement of the bubble across the light sensor in a frame multiplied by the frame refresh rate.

9. The method according to claim 8, further comprising: The one or more processors calculate the velocity of the bubble based on: (1) the amount of movement across the leading edge of the light sensor in the first detected motion multiplied by the frame refresh rate, (2) the amount of movement across the trailing edge of the light sensor in the second detected motion multiplied by the frame refresh rate, or (3) the average of the amount of movement across the leading edge of the light sensor in the first detected motion multiplied by the frame refresh rate and the amount of movement across the trailing edge of the light sensor in the second detected motion multiplied by the frame refresh rate.

10. The method according to claim 7, further comprising: determining, by the one or more processors, whether a break in the fluid flow has occurred by determining whether the bubble length is greater than a predetermined multiple of the diameter of the tube; as well as Whether the bubble is classified as a small bubble is determined by the one or more processors by determining whether the bubble length is less than a predetermined fraction of the diameter of the tube.

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