HK40117405A - Ingestible device with propulsion capability including direct z-axis translational mobility - Google Patents

Description

An ingestible device with propulsion capabilities including direct Z-axis translational movement.

Cross-references to related applications

This application claims the benefit of U.S. Provisional Patent Application No. 63/343,694, filed May 19, 2022, the entire contents of which are incorporated herein by reference.

Technical Field

This disclosure relates to an apparatus designed to generate images of biological structures located inside a living organism and to transmit those images to a device located outside the living organism.

Background Technology

Endoscopy is a medical procedure in which structures within a living body are visually examined using a camera attached to the end of a flexible tube. Alternatively, an optical fiber exposed near the end of the flexible tube can carry light reflected from structures within the body to a camera located outside the living body. The flexible tube is used to position the camera or optical fiber in the desired location. A physician can diagnose conditions affecting the living body by examining the images generated by the camera. For example, during upper endoscopy, a flexible endoscope can be inserted through the patient's mouth or nose, allowing the physician to examine the esophagus, stomach, or upper part of the small intestine (duodenum). During lower endoscopy, or "colonoscopy," an endoscope is inserted through the rectum, allowing the physician to examine the colon.

Advances have been made in the quality, reliability, and safety of endoscopes. For example, improvements in camera resolution have allowed medical professionals to provide more informed (and therefore more accurate) advice. However, endoscopy is an invasive procedure and therefore carries several potential complications. Patients may suffer discomfort, infection, unexpected reactions to sedation (including death), bleeding (e.g., due to the removal of tissue for testing as part of a biopsy), or tissue tearing due to friction as the flexible tube is advanced through bends, especially in cancer patients whose gastrointestinal (Gl) tract tissues are weakened by chemotherapy drugs, or in pediatric patients with more fragile anatomy and/or smaller bodies.

Furthermore, endoscopy can be a time-consuming procedure requiring expensive hospital resources. For example, patients may be instructed to prepare for an endoscopy at home, travel to a medical setting, and remain there until sufficient recovery occurs. While the endoscopy itself typically lasts only 15–30 minutes, the experience can take 8–12 hours. The sedation-related recovery time spent in a medical setting such as a hospital or clinic can be a significant component of the total cost of the procedure.

Attached Figure Description

The various features of this technology will become more apparent to those skilled in the art through a study of the specific embodiments in conjunction with the accompanying drawings. Embodiments of this technology are illustrated in the drawings by way of example rather than limitation, wherein the same reference numerals may indicate similar elements.

Figure 1 shows a cross-sectional view of an example of a propulsion-driven ingestible device designed to monitor the internal environment as it travels through a living body (e.g., a human or animal) under its own power.

Figure 2A shows a front perspective view of the payload section of the ingestible device.

Figure 2B is a rear perspective view including the payload section of the ingestible device of Figure 2A.

Figure 3 is a perspective view of the power section of the ingestible device.

Figure 4 is a perspective view of the drive section of the ingestible device.

Figure 5A includes a perspective view of the propulsion section of the ingestible device.

Figure 5B includes a transparent perspective view of the propulsion section of the ingestible device shown in Figure 5A.

Figure 5C shows how the propulsion unit can be arranged adjacent to the stator blades in the distal element of the ingestible device.

Figure 5D is a rear view of the separated distal element of Figure 5C.

Figure 6A includes a perspective view of an ingestible device having a circular structural body with a central axis passing through it.

Figure 6B includes a side view of the ingestible device of Figure 6A.

Figure 6C includes a rear view of the ingestible device of Figure 6A.

Figure 7A includes a cross-sectional view of the ingestible device, showing how a seal formed from a stamped or drilled sheet, being too small in size compared to the diameter of the motor shaft, can create a single contact line between the seal and the motor shaft.

Figure 7B shows how the orifice can be secured within the formed recess when the seal is encapsulated within the main seal body.

Figure 8A depicts an example of a flexible printed circuit board assembly (PCBA) in an unfolded form.

Figure 8B depicts the flexible PCBA of Figure 8A in a folded form.

Figure 9 includes a high-level illustration of the communication between the device and the controller designed for ingestion by a live human, through which the movement of the ingestible device can be controlled.

Figure 10 illustrates a flowchart of the process of monitoring the in vivo environment using a device designed for ingestion by a living organism.

Figure 11 shows a flowchart of the process for controlling a propulsive ingestible device with optical sensors as it travels through a living body.

Figure 12 illustrates an example of a communication environment, which includes a propulsion-type ingestible device communicatively connected to a controller.

Figure 13 is a block diagram illustrating an example of a processing system in which at least some of the operations described herein can be implemented.

Figure 14 is a perspective view of an ingestible device that includes a motor with thrust axes perpendicular to each other and providing direct translation along the z-axis.

Figure 15 is a perspective view of some internal components of the ingestible device of Figure 14.

Figure 16 is another perspective view of some internal components of the ingestible device of Figure 14.

Figure 17 is a bottom view of the ingestible device in Figure 14.

Figure 18 is an orthogonal schematic top view of the ingestible device of Figure 14.

Figure 19 is an orthogonal schematic left-side view of the ingestible device of Figure 14.

Figure 20 is an orthogonal schematic rear view of the ingestible device of Figure 14.

Figure 21 is a cross-sectional perspective view of the motor assembly according to another embodiment of the ingestible device.

Figure 22A is a side sectional view of the motor assembly in Figure 21.

Figure 22B is a top sectional view of the motor assembly in Figure 21.

Figure 23A shows a first perspective view of the motor assembly of Figure 21.

Figure 23B shows a second perspective view of the motor assembly in Figure 21.

Figure 23C shows a third perspective view of the motor assembly in Figure 21.

Figure 23D shows a fourth perspective view of the motor assembly in Figure 21.

Figure 24A shows a first perspective view of the three-motor assembly.

Figure 24B shows a second perspective view of the three-motor assembly.

Figure 24C shows a third perspective view of the three-motor assembly.

Figure 24D shows a fourth perspective view of the three-motor assembly.

Figure 25A shows a first perspective view of the ingestible device, which includes the three-motor assembly shown in Figures 24A to 24D.

Figure 25B shows a second perspective view of the ingestible device of Figure 25A.

Figure 26A shows a first perspective sectional view of the ingestible device of Figure 25A.

Figure 26B shows a second perspective sectional view of the ingestible device of Figure 25A.

Detailed Implementation

In this specification, references to "embodiment," "an embodiment," etc., mean that a particular feature, function, structure, or characteristic described is included in at least one embodiment of the technology described herein. The appearance of such phrases in this specification does not necessarily refer to the same embodiment. Furthermore, the mentioned embodiments are not necessarily mutually exclusive.

Contemporary research has begun to explore more effective ways to monitor the body's internal environment. For example, several companies have developed cameras capable of capturing images of the digestive tract. Typically, these cameras are placed inside capsules the size of vitamins that patients can swallow. As the capsule travels through the digestive tract, the camera can generate hundreds or thousands of images, which can be wirelessly transmitted to an electronic device worn by the patient. This procedure is known as "capsule endoscopy."

Capsule endoscopy allows medical professionals to observe internal environments, such as the small intestine, which are not easily accessible with conventional endoscopes. However, capsule endoscopy remains a relatively uncommon procedure. One reason for this is the lack of camera control after the capsule is ingested. As the capsule travels naturally through the digestive tract, the camera may miss areas of focus due to the capsule's orientation. Another reason is that the apparatus used for capsule endoscopy can take several hours to reach the target anatomy, followed by several more hours to record images. The patient may then need to return to a medical setting (e.g., a hospital or clinic) to deliver the recorded images.

Therefore, this paper introduces a controllable propulsion ingestible device, which includes a capsule (also called a "shell" or "casing"), a camera, an antenna, and one or more propulsion components and propulsion control elements. Because the ingestible device is designed to propel itself through a living body, it may be referred to as a "propulsion device".

As the ingestible device traverses the gastrointestinal tract, a camera can generate images. The camera can be designed to capture images at various frame rates, such as 2, 6, or 15 frames per second (fps). In some embodiments, the camera can capture more than 15 fps. The frame rate can vary based on the speed of the ingestible device's movement. For example, the ingestible device can be designed to increase the frame rate as the speed of movement increases. The images generated by the camera are forwarded to an antenna for transmission to electronic devices located outside the living body. More specifically, a processor can send the images to a transceiver, which is responsible for modulating the images onto the antenna for transmission to electronic devices. In some embodiments, the images are transmitted to electronic devices in real time, allowing medical professionals to take appropriate action based on the content of the images. For example, a medical professional can identify areas of interest requiring further examination while reviewing the images. In this case, a propulsion component (one or more) can orient the propulsive ingestible device so that the camera focuses on the area of interest. Such action allows the ingestible device to collect additional data about the area of interest (e.g., in the form of images, biometrics, etc.).

Medical professionals can be general practitioners, specialists (such as surgeons or gastroenterologists), nurses, or technicians responsible for managing the ingestible device as it travels through a living body. However, unlike traditional endoscopy, medical professionals do not need to be close to the patient being examined (also known as the "subject"). For example, medical professionals can examine images generated by cameras on electronic devices located in a remote hospital while the patient lies in another environment, such as a home, a battlefield, etc. In this way, the technologies described in this paper can be used to extend the capabilities of traditional GL departments.

Embodiments may be described with reference to specific capsule shapes, propulsion components, sensors, networks, etc. However, those skilled in the art will recognize that the features of these embodiments are equally applicable to other capsule shapes, propulsion components, sensors, networks, etc. For example, although a feature may be described in the context of an ingestible sensor having multiple propellers arranged in a cross-shaped configuration, that feature may be implemented in an ingestible sensor having another type of propeller or a different arrangement of propellers or a combination of these variations.

Overview of Ingestible Devices

Figure 1 shows a cross-sectional view of an example of an ingestible device 100 designed to monitor the internal environment as it travels through a living organism (e.g., a human or animal). Note that Figure 1 and other illustrations in this document are not drawn to scale and are shown significantly enlarged for clarity. Because the ingestible device 100 can be designed to propel itself through a living organism, it may be referred to as a “propulsion device.” The ingestible device 100 includes a capsule 102 having a cylindrical body 104 and hydrodynamically abrasive-shaped ends 106a-b. An example of a hydrodynamically abrasive-shaped end is a circular shape that does not cause damage upon contact with living tissue, such as the generally hemispherical end shown in Figure 1. This geometry may be referred to as a “spherocylindrical.” While the ingestible device 100 shown in Figure 1 has a generally hemispherical end, other hydrodynamically shaped ends may be included in other embodiments. For example, at least one end of the capsule 102 may be a dome with a flat portion through which light can be guided toward an optical sensor. As another example, at least one end of capsule 102 may be a truncated cone. At least one end of capsule 102 may also have a rounded corner, leaving a flat or minimally curved surface along those ends. The cylindrical body 104 and the hemispherical ends 106a-b may be collectively referred to as “structural components” of capsule 102. To avoid contamination of the cavity defined by the cylindrical body 104 and/or the hemispherical ends 106a-b, the structural components may be hermetically sealed to each other.

In some embodiments, these structural components comprise the same material. For example, the structural components may comprise plastics (e.g., polyethylene (PE), polyvinyl chloride (PVC), polyetheretherketone (PEEK), acrylonitrile butadiene styrene (ABS), polycarbonate, nylon, etc.), stainless steel, titanium-based alloys, or another biocompatible material. As used herein, the term "biocompatible" means harmless to living tissue. Biocompatible polymers may be 3D printed, machined, sintered, injection molded, or otherwise formed around the components of the ingestible device 100. In other embodiments, these structural components comprise different materials. For example, the hemispherical end 106a with the optical sensor 110 mounted may be made of transparent plastic, while the other hemispherical end 106b and the cylindrical body 104 may be made of polymer or metal alloy. Furthermore, these structural components may include a coating that inhibits the structural components themselves from being exposed to the in vivo environment. For example, these structural components may be coated with silicone rubber, diamond-like carbon, Teflon, or other biocompatible, hydrophobic, or hydrophilic coatings, which contribute to the safety, durability, or operational efficiency of the ingestible device 100. Additionally or alternatively, these structural components may be coated with antimicrobial materials, such as antibiotic-loaded polymethyl methacrylate (PMMA).

As shown in FIG1, at least one hemispherical end 106a may include an opening 108 through which the field of view of the optical sensor 110 extends. In some embodiments, the opening 108 is filled with a transparent material, such as glass or plastic. Alternatively, the optical sensor 110 may be positioned such that its outermost lens is substantially aligned with the outer surface of the hemispherical end 106a, or the optical sensor 110 may be positioned such that the focal length of the lens is similar to the radius of the hemispherical end 106a, ensuring focus for any anatomical structure directly contacting the ingestible device 100. While the hemispherical end 106a shown in FIG1 includes a single opening, other embodiments of the hemispherical end 106a may include multiple openings (e.g., for multiple optical sensors, biometric sensors, or combinations thereof). In some embodiments, the hemispherical end 106a is entirely constructed of a transparent material. In such embodiments, the hemispherical end 106a may not include a dedicated opening for the optical sensor 110, since the optical sensor 110 can use electromagnetic radiation that has already penetrated the transparent material to generate image data. The hemispherical end 106a may include surface features that can diffuse or guide light away from the ingestible device 100. In addition, a portion of the hemispherical end 106a may be made substantially opaque to suppress or eliminate intermittent reflections of light that may interfere with the optical sensor 110.

Due to ease of manufacture, opening 108 is typically circular. However, opening 108 can have other forms. For example, in some embodiments, opening 108 is rectangular, while in other embodiments, opening 108 has a rectangular portion with circular endpoints. These circular endpoints may be oriented on opposite sides of the hemispherical end 106a, such that an optical sensor positioned below the circular endpoints can observe the in vivo environment along both sides of the push-type ingestible device 100.

In various embodiments, capsule 102 may have any of a variety of different sizes, such as any of those listed in Table 1.

size 000 00 0 1 2 3 4 Internal cavity volume (ml) 1.37 0.91 0.68 0.50 0.37 0.30 0.21 Length (mm) 35 30 29 26.5 twenty four 21.5 19.5 Diameter (mm) 15 13.5 11 7 6.5 6 5.5

Table 1: Sample capsule dimensions.

As shown in Figure 1, the ingestible device 100 may include four sections with different functions: a payload section 200, a power section 300, a drive section 400, and a propulsion section 500. Each of these sections is described in more detail below with reference to Figures 2, 3, 4, and 5. Although these sections are shown as distinct from each other, the components associated with each section may not necessarily be located within the corresponding boxes shown in Figure 1. For example, the power section 300 may include a power distribution unit that extends into the payload section 200, drive section 400, and/or propulsion section 500 to deliver power to the components in those sections.

Figure 2A shows a front perspective view of the payload section 200 of the ingestible device, while Figure 2B shows a rear perspective view of the payload section 200. The payload section 200 may include an optical sensor 202, a power and data bus 204, a control unit 206, a manipulator controller 208, an airtight seal 210, and an illumination source 212. Embodiments of the ingestible device may include some or all of these components, as well as other components not shown herein. For example, if the ingestible device is designed for imaging only, the payload section 200 may not include the manipulator controller 208, as no manipulation will be performed.

As the ingestible device traverses the gastrointestinal tract, the optical sensor 202 can generate image data based on electromagnetic radiation reflected by structures located within the gastrointestinal tract. For example, if the optical sensor 202 is a camera, images or videos can be captured as the ingestible device travels through the body. Another example of the optical sensor 202 is an infrared sensor. Other embodiments of the ingestible device may include an acoustic sensor, such as ultrasound, instead of the optical sensor 202, or may include an acoustic sensor in addition to the optical sensor 202. Thus, the ingestible device may include one or more sensors configured to generate image data based on energy reflected by structures within the body. An illumination source 212 (also referred to as a “light source”) housed within the ingestible device is typically responsible for generating electromagnetic radiation. An example of the illumination source 212 is a light-emitting diode (LED). Here, the illumination source 212 is configured such that electromagnetic radiation is emitted through the same aperture in the capsule, and reflected electromagnetic radiation is received through the aperture. In other embodiments, the illumination source 212 is arranged such that electromagnetic radiation is emitted through a first aperture in the capsule, while reflected electromagnetic radiation is received through a second aperture in the capsule.

Some embodiments of the propulsive ingestible device include multiple optical sensors 202. For example, the ingestible device may include a camera equipped with a charge-coupled device (CCD) or complementary metal-oxide-semiconductor (CMOS) sensor assembly capable of detecting electromagnetic radiation in the visible range and an infrared sensor capable of detecting electromagnetic radiation in the infrared range. These optical sensors can generate different datasets that collectively provide meaningful information that can be used for diagnostics and assisted spatial positioning. Here, for example, the infrared sensor may be able to measure the heat emitted by objects included in a color image captured by the camera.

The power and data bus 204 (also referred to as the “bus” or “bus connector”) is responsible for distributing data and/or power to various components within the propulsive ingestible device. For example, bus 204 may forward image data generated by optical sensor 202 to control unit 206, and control unit 206 may forward the image data to a transceiver configured to modulate the data onto an antenna for transmission to a receiver located outside the body. As further described below, the receiver may be part of an electronic device on which an individual can view images corresponding to the image data, control the ingestible device, etc. Bus 204 may include cables, connectors, wireless chipsets, processors, etc. In some embodiments, bus 204 manages data and power on separate channels. For example, bus 204 may use a first set of cables to manage data and a second set of cables to manage power. In other embodiments, bus 204 manages data and power on a single channel (e.g., having components capable of transmitting data and power simultaneously).

Control unit 206 may be responsible for managing other components in the propulsive ingestible device. For example, control unit 206 may be responsible for parsing input received by the antenna and then providing appropriate instructions to other components in the propulsive ingestible device. As further described below, an individual may use an external controller device (or simply "controller") to provide input. Input may represent a request to start using optical sensor 202 to generate image data, a request to start using antenna to transmit image data, a request to stop using optical sensor 202 to generate image data, a request to stop using antenna to transmit image data, or a request to move the propulsive ingestible device to a desired location. Control unit 206 may include any combination of a central processing unit (CPU), graphics processing unit (GPU), application-specific integrated circuit (ASIC), field-programmable gate array (FPGA), microcontroller, logic component, or other similar processing unit.

In some embodiments, the propellable ingestible device is designed to manipulate the in vivo environment in a certain way. In such embodiments, the payload section 200 may include interventional components such as biopsy attachments, needles, cutting mechanisms, propulsion mechanisms, cauterization mechanisms (e.g., ohmic cauterizers or radiofrequency cauterizers), drug delivery mechanisms, etc. Manipulator controller 208 can control these interventional components. For example, manipulator controller 208 may control a biopsy attachment extending through the capsule to collect tissue based on instructions received from control unit 206.

To prevent fluid from entering the capsule, the payload section 200 and the power section 300 can be hermetically sealed to each other. Therefore, the hermetically sealed element 210 can be fixed along the interface between the payload section 200 and the power section 300. The hermetically sealed element 210 can be made of epoxy resin, metal, glass, plastic, rubber, ceramic, adhesive, or other sealing materials. One factor determining the suitability of the materials used to form the hermetically sealed element 210 is whether the surface energy of those materials is similar to the surface energy of the substrate to which the hermetically sealed element 210 is bonded. Therefore, the composition of the hermetically sealed element 210 can depend on the composition of the capsule's structural components. For example, if the capsule's structural components include stainless steel, the hermetically sealed element 210 can be made of epoxy resin in which metal (e.g., stainless steel) particles are suspended. Alternatively, the hermetically sealed element 210 can be formed using flexible gaskets, adhesive films, welding, seals, etc.

Figure 3 includes a perspective view of the power section 300 of the ingestible device. The power section 300 may include a power component 302, a power distribution unit 304, and hermetic seals 306a-b fixed along each end. The hermetic seals 306a-b may be substantially similar to the hermetic seal 210 fastened to the payload section 200 as described with respect to Figure 2. Furthermore, the hermetic seal 210 fastened to the lower end of the payload section 200 may be the same seal as the hermetic seal 306a fastened to the upper end of the power section 300. Thus, a single hermetic seal can engage the payload section 200 and the power section 300.

The power supply component 302 (also referred to as the "energy storage component") may be configured to supply power to other components of the propelled ingestible device, such as any optical sensors (one or more), biometric sensors (one or more), processors (one or more), communication components (e.g., transmitters, receivers, transceivers, and antennas), and any other components that require power. For example, the power supply component 302 may be responsible for providing the power required by an optical sensor (e.g., optical sensor 202 of FIG. 2) to generate image data. As another example, the power supply component 302 may be responsible for generating the driving energy to be applied to an antenna to enable the wireless transmission of image data to a receiver located outside the body.

The power component 302 may be, for example, a silver oxide battery, a nickel-cadmium battery, a lithium battery (e.g., a battery with a liquid cathode, a solid cathode, or a solid electrolyte), a capacitor, a fuel cell, a piezoelectric component, or another energy capture and/or storage device. In some embodiments, the power component 302 includes one or more battery panels exposed to a fluid through which the ingestible device travels. In such embodiments, the power component 302 may be designed to operate on a fluid (e.g., bodily fluids such as stomach acid) that is readily accessible within the in vivo environment in which the ingestible device is designed. Typically, batteries operate by transporting positively charged ions from one place to another through a solution called an electrolyte, which contains both positively and negatively charged particles. However, in the case of exposed battery panels, a pair of metal electrodes may be attached to the outer surface of the ingestible device. One metal electrode (e.g., composed of zinc) can emit ions into the fluid, which acts as an electrolyte by transmitting a small current to the other metal electrode (e.g., composed of copper).

In some embodiments, the power component 302 is designed to wirelessly receive power from a source located outside the body. In such embodiments, the source may generate a time-varying electromagnetic field that transmits power to the power component 302. The power component 302 can extract power from the electromagnetic field and then supply the power to other components in the ingestible device as needed. The same antenna used for data transmission or different antennas, inductively coupled coils, or capacitively coupled structures can be used to receive the power. The source may be a controller for controlling the ingestible device, electronics for examining image data, or some other electronic device (e.g., a mobile phone or wireless charger belonging to the patient). Alternatively, the wireless power source may be included in an article of article (e.g., a belt or strap) that can be worn such that the wireless power source remains near the ingestible device as it travels through the living body. Such a wearable article may include a battery pack integrated within the article itself or attached to the patient. Furthermore, such a wearable article may include one or more antennas for data transmission.

The power component 302 can be designed to be fitted into a specific segment of the ingestible device. Here, for example, the power component 302 has the form of a button battery, which allows the power component 302 to be secured within the cylindrical body of the capsule. However, other embodiments of the power component 302 can be designed to be fitted into the hemispherical end of the capsule or another region within the capsule.

As described above, the power distribution unit 304 is responsible for distributing the power stored in the power component 302 to other components in the ingestible device. Therefore, components of the power distribution unit 304 can extend into the payload section 200, drive section 400, and/or propulsion section 500. For example, the power distribution unit 304 may include cables connected to optical sensors, bus connectors, control units, control sensors, and/or manipulator controllers that may be located in the payload section 200. The power distribution unit 304 may also include components for regulating, stabilizing, or modifying the power to be distributed. Examples of such components include voltage regulators, converters (e.g., DC-DC converters), metal-oxide-semiconductor field-effect transistors (MOSFETs), capacitors, transformers, resistors, or inductors.

Figure 4 shows a perspective view of the drive section 400 of the ingestible device. The drive section 400 may include one or more energy-to-motion converters 402, one or more heat transfer components 404, and hermetic seals 406a-b fixed along each end. The hermetic seals 406a-b may be the same as or substantially similar to the hermetic seal 210 fastened to the payload section 200 as described with respect to Figure 2. Furthermore, the hermetic seal 306b fixed to the lower end of the power section 300 may be the same seal as the hermetic seal 406a fixed to the upper end of the drive section 400. Thus, a single hermetic seal may connect the power section 300 and the drive section 400.

When receiving power from a power distribution unit (e.g., power distribution unit 304 in Figure 3), one or more mechanical power converters 402 can drive another component of the ingestible device. Here, for example, the drive section 400 includes multiple motors, and each motor can be responsible for driving a different thruster. Examples of motors 402 include DC or AC electric motors, actuators made of shape memory alloys, electromagnets, shafts, piezoelectric components, etc. The thrusters can be connected to the motors via one or more shafts, gears, levers, bearings, etc.

Components in the ingestible device can generate heat, which should be dissipated to avoid damage in the body. For example, if the propeller(s) are driven for an extended period of time, components such as energy-motion converters and motor housings can generate heat. Therefore, these components may include or be connected to one or more heat transfer components 404 capable of helping to dissipate this heat. In some embodiments, the heat transfer component 404 releases heat directly into a fluid (e.g., water, bile, gastric acid, or mixtures thereof) surrounding the ingestible device. For example, the motor housing may be constructed of a material with acceptable thermal conductivity (e.g., stainless steel) to facilitate heat dissipation. In other embodiments, the heat transfer component 404 releases heat into the capsule. As heat is released into the capsule, it can be naturally transferred to the fluid surrounding the ingestible device through conduction and convection.

Figure 5A includes a perspective view of the propulsion section 500 of the ingestible device, while Figure 5B includes a transparent perspective view of the propulsion section 500 of the ingestible device. The propulsion section 500 may include one or more thrusters 502, one or more air inlets 504, and a hermetically sealed member 508 fixed along its upper end. The hermetically sealed member 508 may be substantially similar to the hermetically sealed member 210 fastened to the payload section 200 as described with respect to Figure 2. Furthermore, the hermetically sealed member 508 may be the same seal as the hermetically sealed member 406b fixed to the lower end of the drive section 400. Thus, a single hermetically sealed member may connect the drive section 400 and the propulsion section 500.

As described above, the ingestible device may include one or more propulsion components (also referred to as a "propulsion system" or "thrust component"). Each propulsion component may include a thruster and an energy-motion converter, the thruster being configured to generate a propulsive force for moving the ingestible device, and the energy-motion converter being configured to supply power to the thruster. Here, for example, propulsion section 500 includes four rotors 502 driven by four motors located in drive section 400. In some embodiments, each thruster is driven by a different mechanical power converter. In other embodiments, multiple thrusters may be driven by a single energy-motion converter. For example, a single motor may be responsible for supplying prime movers to multiple thrusters, but the speed of each thruster may be varied by mechanical connections (e.g., a clutch system or a gear system).

As further described below, multiple thrusters 502 can be arranged to facilitate movement along different axes. In Figures 5A-B, for example, four thrusters 502 are arranged radially around a central axis 516 defined by the capsule in a cross configuration. More specifically, these thrusters 502 are positioned radially offset from the central axis and offset around the central axis at different angles. By independently driving these thrusters 502, movement in any direction or orientation can be achieved in a manner similar to that of a quadcopter. Thus, the intakeable device can be commanded to move forward and backward at different speeds. Furthermore, the intakeable device can be instructed to change its orientation by rotating about three mutually perpendicular axes. These changes in orientation and forward/reverse movement can be translated into changes in yaw (normal axis), pitch (lateral axis), and roll (longitudinal axis), and thus can represent movement to any position in three-dimensional space.

In Figures 5A-B, the propeller 502 is a rotor capable of drawing in fluid through an air inlet 504 formed in the capsule. As used herein, the term "rotor" refers to a component capable of rotation to generate propulsion. An example of a rotor is a propeller. However, other propellers may be used instead of rotors or in addition to rotors. Examples of propulsion components include helices, fins, impact attachments (also called "flaps"), wave mechanisms, etc. Furthermore, the propulsion component may be arranged along the cylindrical body of the capsule rather than in the hemispherical end of the capsule; or, in addition to being arranged in the hemispherical end of the capsule, the propulsion component may also be arranged along the cylindrical body of the capsule. For example, the ingestible device may include oscillating fins arranged along opposite sides of the cylindrical body of the capsule. These oscillating fins may be used in conjunction with propellers (one or more), helices (one or more), or impact attachments (one or more) located in the hemispherical end of the capsule to provide greater control over the movement of the ingestible device.

As shown in Figures 5A-B, the capsule may include one or more channels through which fluid may be drawn in by one or more thrusters 502. Each channel includes an inlet 504 and an outlet 506, through which fluid may be drawn in through the inlet 504 and discharged through the outlet 506. Examples of inlets 504 include conduits, lumens, blades, tubes, etc. While the embodiments shown in Figure 5 include the same number of thrusters 502 and inlets 504, this is not always the case. For example, a thruster mounted in the hemispherical end of the capsule may be able to draw fluid in through one or more inlets to prevent moving parts (such as thrusters 502) from contacting living tissue. Fixed stator blades can be used to optimize the efficiency of the rotating propeller in order to control eddies, increase speed, and increase controllability, as discussed further below with respect to Figures 5C-5D. In some embodiments, a coaxial counter-rotating propeller can be used to completely eliminate the fixed stator blades. The number and geometry of the propeller and guide vane blades can be adjusted to optimize the removal of bubbles and debris based on diameter, speed, and fluid properties.

In some embodiments, a filter is placed in at least one of the channels defined by the capsule. For example, a filter may be fixed in each channel defined by the capsule. Filters may be necessary to ensure that objects larger than a certain size suspended in the fluid inhaled through inlet 504 are removed. For example, if the ingestible device is designed for use in the gastrointestinal tract, the filters (multiple filters) may be designed to prevent solid particles (e.g., food particles) from contacting the propellers (multiple propellers) 502.

Another problem is that propellers tend to exert rotational motion (or “stirring”) on the fluid rather than generate thrust, unless properly designed. This problem can be addressed by adding one or more stator guide vanes (also called “stator blades”) to each flow channel. The terms “stator guide vane” and “stator blade” refer to fixed blades positioned within the flow channel through which fluid is drawn in and then ejected by the propeller. Figure 5C illustrates how propeller 502 can be arranged adjacent to the stator blades 514 in the distal element 512 of the ingestible device of Figures 5A-B. These stator blades 514 can be used to straighten the fluid flow, reduce the stirring effect, and increase thrust and thrust consistency. As shown in Figure 5C, each propeller 402 can be connected to a separate motor housing 510, in which the motor responsible for driving the propeller is located. The propellers 502 (and therefore the motor housings 510) can be arranged in a cruciform configuration for better control of thrust.

Figure 5D is a separated rear view of the distal element 512 shown in Figure 5C. In embodiments where the distal element 512 includes a plurality of stator blades 514, the stator blades 514 may be arranged radially about the geometric center of the distal element 512. Typically, the stator blades 514 are arranged substantially uniformly about the geometric center, as shown in Figure 5D. However, in some embodiments, the stator blades 514 are arranged non-uniformly about the geometric center.

Figures 6A-C include perspective, side, and rear views of an ingestible device 600 having a non-invasive structural body 602 with a central axis 612 passing through it. The structural body 602 shown in Figures 6A-6C is a spherical cylinder comprising cylindrical segments interconnected between hemispherical segments. In other embodiments, the structural body 602 may be elliptical, rectangular, teardrop-shaped, or similar shapes.

As described above, the ingestible device 600 may include one or more thrusters for controlling movement along three mutually perpendicular axes. Here, for example, the ingestible device 600 includes four rotors 604a-d arranged radially around the structural body 602 perpendicular to the central axis 612. The four rotors 604a-d may include a first pair of rotors 604a-d arranged radially opposite each other relative to the central axis 612 and a second pair of rotors 604c-d arranged radially opposite each other relative to the central axis. Each pair of rotors may be configured to share the same chirality; for example, when rotated clockwise relative to the central axis 612, rotors 604a-b may all generate a forward thrust. Simultaneously, the pairs of rotors may be configured to have opposite chirality; for example, when all four rotors rotate clockwise relative to the central axis 612, rotors 604a-b may generate a forward thrust, while rotors 604c-d may generate a backward thrust. As shown in Figure 6C, the first and second pairs of rotors 604a-d can be arranged in a cross configuration, such that adjacent rotors rotate in opposite directions to generate thrust in the same direction, while radially opposite rotors rotate in the same direction to generate thrust in the same direction. This configuration allows for independent control of thrust, pitch, yaw, and roll through the combination of the effects of the individual rotors; thus, position and orientation control can be achieved in a manner similar to that of a quadcopter.

Each rotor may be located in a different channel defined by the structure 602, and each channel may include an inlet 606 and an outlet 608, through which fluid is drawn in by the corresponding rotor and through which fluid is discharged by the corresponding rotor. Generally, the channels are defined to pass through the structure 602 in a direction substantially parallel to the central axis. Here, for example, the inlet 606 of each channel is located in a cylindrical section of the structure 602, while the outlet 608 of each channel is located in a hemispherical section of the structure 602. In operation, rotors 604a-d may draw fluid through the inlet 606 to generate a flow 610 that propels the ingestible device in a particular direction. In some embodiments, the channels are tapered. For example, the inlet 606 of each channel may have a smaller diameter than the outlet 608, or the inlet 606 of each channel may have a larger diameter than the outlet 608.

In some embodiments, each rotor is designed to rotate in both a primary and a secondary direction. For example, the first pair of rotors 604a-b may be configured to rotate clockwise and counterclockwise relative to the central axis 612. Similarly, the second pair of rotors 604c-d may be configured to rotate clockwise and counterclockwise relative to the central axis 612. Thus, while the flow 610 is shown flowing toward a first end 614 (also referred to as the “distal end”) of the ingestible device 600, the flow 610 may alternatively flow toward a second end 616 (also referred to as the “proximal end”) of the ingestible device 600.

As described above, the term "rotor" as used herein refers to a component capable of rotation to generate propulsion. Propulsion imparts momentum to the surrounding fluid, resulting in motion. Depending on the speed and operational requirements of the ingestible device 600, the structural body 602 may be fitted with one, two, three, four, or more rotors. In Figures 6A-C, for example, four rotors are arranged in a cross-shaped configuration within the first end 614 of the structural body 602. In other embodiments, three rotors are arranged in a triangular configuration within the first end 614 of the structural body 602.

Each rotor can be driven independently by a different motor. In Figures 6A-C, for example, the ingestible device 600 includes four motors configured to supply power to four rotors 604a-d. In other embodiments, multiple rotors can be driven by a single mechanical power converter. For example, a single motor could be responsible for supplying power to the first pair of rotors 604a-b, but the speeds of these rotors can be varied by mechanical connections (e.g., a clutch system or a gear system).

In some embodiments, each rotor has a fixed pitch. In Figures 6A-C, for example, four rotors 604a-d are fixedly arranged along a radial plane perpendicular to the central axis 612. In other embodiments, at least one rotor has a variable pitch. In such embodiments, greater control over the movement of the ingestible device 600 can be achieved by simultaneously controlling the pitch and rotation of the rotors 604a-d.

The rotor may be composed of one or more biocompatible materials. Examples of biocompatible materials include titanium alloys, stainless steel, ceramics, polymers, fiber-reinforced polymers (e.g., glass fiber or carbon fiber), plastics (e.g., polycarbonate, nylon, PEEK, or ABS), resins, composite materials, etc. Furthermore, each rotor may have an antibacterial, hydrophobic, or hydrophilic coating applied thereto. For example, each rotor may be coated with PMMA carrying antibiotics. The coating applied to the rotor may depend on the type of in vivo environment designed for the ingestible device 600.

Typically, to manufacture rotors, multiple blades are attached to the hub by welding, gluing, or optionally by forging the entire rotor as a single unit. The number of blades can depend on desired efficiency, speed, acceleration, maneuverability, etc. For example, a 3-bladed rotor exhibits good acceleration compared to other types of rotors, while a 4-bladed rotor exhibits good maneuverability compared to other types of rotors. Rotors with a higher number of blades (e.g., rotors with 5 or 6 rotor blades) exhibit good holding power in turbulent internal environments (e.g., those with high flow velocities). Single-bladed rotors can offer advantages in terms of manufacturability and durability. In the embodiments shown in Figures 6A-C, each rotor includes three helical surfaces acting together to rotate through a fluid (e.g., water, bile, etc.) via a helical effect.

One of the difficulties in generating thrust within a small area is the persistent presence of air bubbles that can become trapped near rotors, such as propellers, preventing proper engagement between the rotor and the fluid. This problem can be addressed by carefully designing the shape, number, and arrangement of the blades along each rotor to help remove the bubbles. Careful matching of blade pitch, internal cavity shape, motor speed, rotor-to-wall clearance, rotor-to-stator blade clearance, and surface material properties will affect both bubble formation and removal.

The rotor can be formed based on a simple truncated Archimedean spiral geometry. Alternatively, as mentioned above, the rotor can be characterized by multiple individual blades having curvatures optimized for propagation in the forward or backward direction. Similarly, if the stator blades are positioned within the channels through which the rotor draws and then ejects fluid, those stator blades can be characterized as flat or curved blades.

Preventing fluid from entering the ingestible device, especially in the propulsion section including the moving motor interface, is also crucial. Therefore, the ingestible device can be implemented with tight tolerances, hydrophobic and/or hydrophilic materials, or mechanical seals. Seals can maintain microscale tolerances and are therefore used to maintain safety and consistency without requiring complex assembly processes. Figures 7A-B illustrate how low-profile and low-friction seals can be implemented to prevent fluid from entering the motor housing of the ingestible device 700.

Figure 7A includes a cross-sectional view of the ingestible device 700, illustrating how the seal 704, formed from a stamped or drilled sheet, is too small compared to the diameter of the motor shaft 702, allowing for the creation of a single contact line 706 between the seal 704 and the motor shaft 702. Sealing performance, static friction, and dynamic friction can be optimized by adjusting dimensional interference and the resulting embedding tension. The stamped or drilled sheet can be made of polytetrafluoroethylene (PTFE) or similar materials (e.g., ultra-high molecular weight (UHMW) polyethylene). This design can be easily manufactured with relatively few machining operations. Another advantage of this approach is that multiple seals can be manufactured at once using a simple drilling jig. By drilling small holes in the sheet (e.g., 0.5-0.6 mm in diameter for a 0.7 mm diameter motor shaft) and then expanding it on the motor shaft 702, circumferential tension (also known as “circumferential stress”) is created. The circumferential tension will cause the expanded hole to protrude slightly, thereby creating a minimum contact line 706 with the motor shaft 702 and reducing friction while providing a seal.

Seal 704 can be manufactured using a hypodermic cannula punch. Multiple seals can be drilled simultaneously on a lathe while still in the hypodermic cannula, using simple jigs and drill guides. Assembly can be accomplished by placing seal 704 on motor shaft 702 and securing it in place with a curable adhesive (e.g., UV-curable adhesive), radio frequency (RF) welding, thermal welding, etc. Seal 704 can be expanded on motor shaft 702 and then potted within main seal body 708 with a curable adhesive or another sealing technique.

As shown in Figures 7A-B, the main seal 708 can be attached to the motor housing 710 using a curable adhesive or another sealing technology. One or more seals can be implemented on a single motor shaft to optimize shaft friction and seal reliability. Continuous lip seals with different clearances can help optimize energy efficiency, aging, and overall safety and performance. As shown in Figure 7B, a recess 712 can be formed when the seal 704 is potted inside the main seal 708. An orifice plate 714, having a hole defined therethrough for receiving the motor shaft 702, can be positioned within the recess to further suppress leakage into the motor housing 710. The orifice plate 714 can be made of plastic, metal, rubber, fluororubber, Teflon, UHMW polyethylene, high-density polyethylene, or similar materials.

Therefore, a manufacturer can obtain a flexible substrate with a substantially circular shape, form a hole at the geometric center of the flexible substrate (e.g., by punching or drilling), and then expand the hole in the flexible substrate around a motor shaft having a diameter larger than the hole. This method can result in an elastic interference fit between the flexible substrate and the motor shaft, thereby forming a seal. The manufacturer can then fix the flexible substrate along its outer periphery to form an hermetic seal. For example, as described above, the flexible substrate can be fixed using a curable adhesive, RF welding, thermal welding, etc.

This is described herein as some or all of the electronic components contained within an ingestible device being mounted on a flexible printed circuit board assembly (PCBA). Figures 8A and 8B depict examples of a flexible PCBA 800 in its unfolded and folded forms, respectively. As shown in Figure 8A, the flexible PCBA may include at least two rigid regions 802 for providing support for components 804 mounted thereon and accompanying solder joints, and for helping to define the structure of the PCBA 800 as a whole. These rigid regions 802 may be connected by flexible regions 806, which are foldable to allow the PCBA 800 to be assembled within an ingestible device. The PCBA 800 may include conductive connections between electronic components to allow the transfer of power and/or data between them. More specifically, the PCBA 800 may include one or more conductive layers serving as connections between electronic components mounted to the rigid regions 802. Each pair of conductive layers may be separated by an insulating layer (also referred to as a “non-conductive layer”) made of a non-conductive material such as polyimide.

Figure 9 includes a high-level illustration of communication between a device 900 designed for ingestion by a live organism and a controller 950, which controls the movement of the ingestible device 900. Because images generated by the ingestible device 900 can be reviewed on the controller 950, the controller 950 may also be referred to as a “data review station” or “data review unit.” Initially, the controller 950 transmits a first input (step 901) instructing the operation of the camera housed within the ingestible device 900. Alternatively, the ingestible device 900 may be designed to automatically operate the camera when the device is first powered on or activated by removal from its packaging.

The ingestible device 900 can cause a camera to generate an image of a structure in a living organism in response to a first input (step 902). This structure can be a biological structure or a non-biological structure (also referred to as a "foreign object"). The ingestible device 900 can then transmit the image to a controller 950 for inspection (step 903). More specifically, a processor responsible for processing the image generated by the camera can forward the image to a transmitter for modulation onto an antenna for wireless transmission to the controller. In some embodiments, the transmitter is part of a transceiver capable of transmitting and receiving communications to and from the controller 950.

The controller 950 may further transmit a second input (step 904) instructing a request to change the position and/or orientation of the ingestible device 900. This second input may be referred to as a “steering command” or a “propulsion command.” The ingestible device 900 may cause at least one propeller to be actuated in response to the second input (step 905). In an instance where multiple propellers are actuated in response to the second input, the ingestible device 900 may generate multiple signals for actuating the multiple propellers. These signals may be different from each other. For example, each of the multiple propellers may rotate at a different speed. As another example, some propellers of the ingestible device 900 may rotate while other propellers of the ingestible device 900 remain stationary.

Figure 10 illustrates a flowchart of a process 1000 for monitoring the internal environment using a device designed for live ingestion. Initially, as part of a capsule endoscopy procedure for observing the gastrointestinal tract, the subject ingests the ingestible device (step 1001). The ingestible device (and its control software) can support several different data collection modes. For example, the ingestible device can support a “general mode” suitable for open navigation and/or a “swallowing mode” suitable for unidirectional passage through the esophagus.

As the ingestible device travels through a living body, optical sensors included in the ingestible device may subsequently begin generating image data (step 1002). In some embodiments, the ingestible device causes the optical sensors to begin generating image data in response to receiving an instruction to do so. The instruction may be submitted, for example, by an operator via a controller communicatively coupled to the ingestible device. In other embodiments, the ingestible device causes the optical sensors to automatically generate image data in response to determining that predetermined criteria have been met. For example, in response to determining that the ingestible device has entered a specific in vivo environment, the ingestible device may cause the optical sensors to begin generating image data. The ingestible device may achieve such a determination by examining biometric data generated by biometric sensors. For example, the ingestible device may determine whether it is currently in the stomach by examining biometric data representing pH measurements. Images may be captured at any resolution of various resolutions, such as 48×48 pixels, 320×240 pixels, or 640×480 pixels. In other embodiments, images may be captured at higher or lower resolutions. The image data may be stored, at least temporarily, in a memory located within the ingestible device (step 1003).

The ingestible device then wirelessly transmits at least some image data via an antenna to a receiver located outside the living body (step 1004). In some embodiments, the receiver is housed in an electronic device associated with the subject. For example, the image data can be transmitted to a mobile phone associated with the subject, and the mobile phone can forward the image data to another electronic device for viewing by an operator responsible for controlling the ingestible device. In some embodiments, the image data is transmitted to the receiver periodically (e.g., every 3 seconds, 5 seconds, 30 seconds, 60 seconds, etc.). In other embodiments, the image data is transmitted to the receiver in real time. That is, the ingestible device can stream image data to the receiver as the optical sensor generates image data.

To reduce the amount of raw data that must be transmitted via bus or wireless link, image data (as well as identification data, telemetry data, etc.) can be compressed in a way that reduces the quantity without significantly affecting the user's perception of quality. For example, algorithms that reduce color/hue differently than intensity, or algorithms that reduce high-frequency content differently than low-frequency content, can be used. Standardized image and/or video compression algorithms such as JPEG, H.264 (MPEG), and H.265 can be used to compress the data. To further reduce the amount of data, the image resolution can be reduced before compression and transmission. For example, an optical sensor may generate an image with a resolution of 640×480 pixels, but this image can be downsampled to a resolution of 320×240 pixels before JPEG compression. The resolution can be adjusted during operation to achieve a desired trade-off between image quality and frame rate (e.g., reducing image quality to increase frame rate when an ingestible device travels through the esophagus). After data has been transmitted via a wireless link, additional compression algorithms can be used, for example, if the data is transmitted to a controller with computational and storage resources available to execute a more stringent compression algorithm than that executed on the ingestible device itself. This additional compression can be used to reduce the size of the data stored on the controller or other electronic devices. Data can be encrypted on the ingestible device, controller, or other electronic devices to prevent unauthorized third parties from accessing patient identification (PH) information or medically sensitive information.

Figure 11 illustrates a flowchart of process 1100 for controlling an ingestible device with optical sensors as it passes through a living body. Initially, the ingestible device is inserted into the living body (step 1101). For example, if the ingestible device is designed to monitor the digestive system, it can be ingested by the subject. As the ingestible device passes through the living body, it receives a first input from a controller located outside the living body, instructing the ingestible device to begin recording image data (step 1102).

The ingestible device can cause the optical sensor to begin generating image data in response to a first input (step 1103). Alternatively, the optical sensor can be configured to automatically begin generating image data after the ingestible device has been removed from its packaging or after a mechanical switch accessible on the outer surface of the ingestible device has been activated. In some embodiments, the ingestible device can be remotely activated by a source located outside the living body via RF signals, magnetic signals, optical signals, etc. For example, the optical sensor can begin generating image data in response to determining that the ingestible device has been outside the packaging for a certain amount of time (e.g., 3 minutes, 5 minutes, 10 minutes, etc.). As another example, the optical sensor can begin generating image data in response to determining that the ingestible device has entered a specific in vivo environment.

The ingestible device can then wirelessly transmit at least some image data to a receiver using an antenna (step 1104). For example, a processor can transmit the image data to a transceiver responsible for modulating the image data onto the antenna for transmission to the receiver. In some embodiments, the image data is transmitted in its raw (i.e., original) form. In other embodiments, the image data is transmitted in a processed form. For example, the processor can filter values from the image data, add metadata (e.g., specifying location, time, or identifier associated with a living organism), etc. As described above, the receiver can be a controller or part of some other electronic device. For example, a medical professional can use a mobile workstation wirelessly connected to the ingestible device to view the image data and control the ingestible device. As another example, a medical professional can view the image data on a tablet and control the ingestible device using a dedicated input device similar to a controller for a video game console.

In some situations, medical professionals may wish to observe specific structures in a living organism. Therefore, the ingestible device may receive a second input indicating a movement command, making the structure observable by an optical sensor (step 1105). In other words, the ingestible device is movable such that the structure is within the field of view (FoV) of the optical sensor. The ingestible device can be moved by changing its position and/or orientation. The ingestible device may determine appropriate drive signals for each propulsion component based on the desired location and/or characteristics of the in vivo environment, such as viscosity, flow rate, temperature, etc. Once the ingestible device has reached the desired location, it may automatically maintain its position until a predetermined time interval has elapsed, or until a command to move to a new location is received from the controller.

The ingestible device can then drive at least one thruster in response to the second input (step 1106). In some embodiments, the thruster is driven entirely based on the second input. For example, if the second input represents a command to move forward, the thruster can be driven to achieve forward movement.

For implementations of ingestible devices powered by onboard batteries, it is generally desirable to minimize battery discharge before the ingestible device is ready for use in order to maximize available power during operation. To avoid battery depletion during transport and storage prior to deployment, the ingestible device may enter a low-power inactive state, in which the current drawn from the battery is minimized or the battery is disconnected from other components (e.g., using mechanical switches, transistors (e.g., MOSFETs), or some other device). To leave this state, the ingestible device may be activated by a sensor.

Some embodiments of the ingestible device employ a photoelectric sensor that prompts activation upon detecting light. The photoelectric sensor can be configured to generate a reading indicating the currently detectable level of visible, infrared, or ultraviolet light. In these embodiments, the ingestible device can be transported and stored in substantially opaque packaging to prevent unintentional or premature activation of the photoelectric sensor. When the packaging is opened, the photoelectric sensor is exposed to light, and the ingestible device can be activated. Other embodiments of the ingestible device employ a low-power magnetic sensor that activates when the ingestible device is exposed to a magnetic field. Alternatively, the ingestible device may include a low-power magnetic sensor that activates when the ingestible device is not exposed to a magnetic field. For example, a magnet may be included in the packaging so that the ingestible device is always exposed to a magnetic field during transport and storage. This embodiment has several advantages. First, the risk of premature activation is minimized because the packaging may accompany the ingestible device until it is about to be opened. Second, the individual responsible for deploying the ingestible device does not need to introduce an activation signal such as a magnetic field. Other embodiments of the ingestible device may use a reed relay as a mechanical power switch to activate the ingestible device upon exposure to a magnetic field. In embodiments where the ingestible device is activated by exposure to a magnetic field, a disposable or reusable magnetic clamp can be used to facilitate activation by maintaining the magnet in the correct orientation relative to the ingestible device. Other embodiments of the ingestible device may be activated by a mechanical element (e.g., a switch or button) that is sealed to prevent fluid ingress but positioned along the outer surface of the capsule for accessibility.

As described above, the ingestible device may have built-in features, such as sensors, software, etc., for performing self-diagnostic tests. Using these built-in features, the health and performance functions of the ingestible device can be tested periodically. These built-in features can also help debug and explore new operating mechanisms. Examples of self-diagnostic tests include checksum errors, software version, battery voltage, power consumption of each motor, testing of other major components, etc. Alternatively or additionally, the camera can be commanded to generate test images (e.g., test images of the package) to be transmitted to a destination (e.g., a controller), where the test images can be compared with a anticipated reference image. Successful transmission of test images requires the ingestible device to be functioning correctly. If no test image is received or the test image is incorrect, it may indicate a defect (e.g., in the ingestible device, communication channel, etc.), and for this defect, an alarm indicating that the ingestible device should not be deployed can be generated.

Communication environment

Figure 12 illustrates an example of a communication environment 1200, which includes an ingestible device 1202 communicatively connected to a controller 1204. An operator can use the controller 1204 to control the ingestible device 1202. Furthermore, the ingestible device 1202 can be configured to transmit data (e.g., image data or biometric data) to one or more electronic devices. Examples of electronic devices include a monitor 1206, a computer server 1208, and a mobile phone 1210. The ingestible device 1202, the controller 1204, and (one or more) electronic devices can be collectively referred to as "networked devices".

In some embodiments, as shown in FIG12, networked devices are connected to each other via peer-to-peer wireless connectivity. For example, ingestible device 1202 may be coupled to controller 1204 via Bluetooth®, Near Field Communication (NFC), Wi-Fi® Direct (also known as “Wi-Fi P2P”), Zigbee®, another commercial peer-to-peer protocol, or a proprietary peer-to-peer protocol. In other embodiments, networked devices are interconnected via a network, such as Personal Area Networks (PANs), Local Area Networks (LANs), Wide Area Networks (WANs), Metropolitan Area Networks (MANs), cellular networks, or the Internet. For example, ingestible device 1202 may be coupled to monitor 1206 and computer server 1208 via a separate LoRa® communication channel.

The connection established between networked devices can be bidirectional or unidirectional. For example, controller 1204 may be allowed to transmit data to ingestible device 1202, even if ingestible device 1202 may not be able to transmit data to controller 1204. Similarly, ingestible device 1202 may be allowed to transmit data to electronic device, even if electronic device may not be able to transmit data to ingestible device 1202.

Embodiments of the communication environment 1200 may include some or all of the networked devices. For example, some embodiments of the communication environment 1200 include an ingestible device 1202 and a single device (e.g., a mobile phone, tablet, or mobile workstation) that serves as a controller and an electronic device on which image data is viewed. As another example, some embodiments of the communication environment 1200 include an ingestible device 1202 and a computer server 1208, on which image data is stored for later viewing. In such embodiments, because the image data will be viewed at a later point in time, the communication environment 1200 does not need to include a controller 1204. As another example, some embodiments of the communication environment 1200 include a dedicated input device without display capabilities that serves as a controller 1204, and an electronic device, such as a tablet or mobile phone, on which image data is viewed. In such implementations, the dedicated input device may be communicatively coupled to the ingestible device and/or the electronic device.

Since the ingestible device 1202 can operate within the body, close proximity to fluids, tissues, etc., can affect the electromagnetic operating characteristics of the antenna. To address this, the antenna can be designed and/or selected to minimize the influence of nearby materials having a relative permittivity significantly different from that of free space. As an example, one embodiment may use a small loop antenna with one or more loops, which primarily interacts with the magnetic field components in the near field and is therefore less affected by the strong influence of the vicinity of high-dielectric materials. Alternatively, the antenna can be designed and/or selected to compensate for the influence of one or more fluids within the living body. As an example, one embodiment may use a straight, bent, curved, or zigzag antenna (e.g., a monopole antenna) where the effective electrical antenna length is between one-eighth and one-third of the transceiver's operating wavelength when the ingestible device 1202 is surrounded by fluids or anatomical structures of the living body. For example, embodiments may use a monopole antenna or a "whip" antenna that is much shorter than a quarter wavelength in free space. While such an antenna would not be optimally tuned in air, proximity to one or more high-dielectric fluids may cause the antenna to behave as if it were significantly longer and properly tuned to the frequency of interest. This method also has the advantage of allowing the use of antennas that are much smaller than those optimal for operation in dry air. The mechanical structure of the antenna can be designed to fit the housing of the ingestible device 1202.

Antenna and transceiver circuitry can be designed so that a single antenna is used for both transmitting and receiving data. Alternatively, multiple antennas can be used. For example, different antennas may provide superior performance under certain orientations or fluid conditions, and the performance of each antenna can be monitored during operation to select the antenna with the highest performance at any given time. In embodiments using wireless power transmission, the ingestible device 1202 can be configured to use a single antenna for both power and data transmission, eliminating the need for additional antennas. Alternatively, different antennas or electromagnetic coupling structures can be used for both power and data transmission, allowing each antenna or electromagnetic coupling structure to be optimized for its respective task.

To allow multiple ingestible devices to operate within very close proximity (e.g., multiple patients receiving treatment in the same room or building), pairing features can be used to establish the aforementioned communication channels. Pairing features can be employed to ensure that each ingestible device communicates with a single controller. To achieve this, a unique identifier can be assigned to each ingestible device during manufacturing. When an ingestible device establishes a communication channel, it can send its identifier to determine whether a communication channel has been established with the appropriate controller. Alternatively or additionally, the ingestible device can attach the identifier (or a shortened/modified identifier) as a tag to data packets to specify the appropriate controller. Thus, each controller can assume that data packets without the correct identifier will be received by another controller and can therefore be ignored. As part of this process, the ingestible device and its corresponding controller can optionally switch to different communication channels or frequencies to avoid having to share time and bandwidth with other pairs of ingestible devices and controllers. The ingestible device and its corresponding controller can optionally change the communication frequency as needed during operation to avoid competition with interfering devices; this strategy is known as "frequency hopping."

Processing system

Figure 13 is a block diagram illustrating an example of a processing system 1300 in which at least some of the operations described herein can be implemented. Components of the processing system 1300 may be housed in an ingestible device (e.g., the ingestible device 100 of Figure 1).

Processing system 1300 may include a central processing unit (“processor”) 1302, main memory 1306, non-volatile memory 1310, wireless transceiver 1312, input/output devices 1318, control devices 1320, a drive unit 1322 including storage medium 1324, and signal generation devices 1328, all communicatively connected to bus 1316. Bus 1316 is shown as an abstraction, representing one or more physical buses and/or point-to-point connections connected via appropriate bridges, adapters, or controllers. Therefore, bus 1316 may include a system bus, a peripheral component interconnect (PCI) bus, a PCI-Express bus, a HyperTransport bus, an Industry Standard Architecture (ISA) bus, a Small Computer System Interface (SCSI) bus, a Universal Serial Bus (USB), an internal integrated circuit ( ^I²C ) bus, or a bus conforming to IEEE Standard 1394.

Processing system 1300 may share a computer processor architecture similar to that of a desktop computer, tablet computer, mobile phone, video game console, wearable electronic device (e.g., watch or fitness tracker), network-connected (“smart”) device (e.g., television or home assist device), augmented or virtual reality system (e.g., head-mounted display), or another electronic device that can perform a set of instructions (sequential or otherwise) that specifies the actions to be taken by processing system 1300.

Although main memory 1306, non-volatile memory 1310, and storage medium 1324 are shown as a single medium, the terms "storage medium" and "machine-readable medium" should be considered as including a single medium or multiple media storing one or more sets of instructions 1326. The terms "storage medium" and "machine-readable medium" should also be considered as including any medium capable of storing, encoding, or carrying a set of instructions that can be executed by processing system 1300.

Typically, routines executed to implement embodiments of this disclosure may be implemented as part of an operating system or a particular application, component, program, object, module, or sequence of instructions (collectively, a “computer program”). A computer program typically includes instructions (e.g., instructions 1304, 1308, 1326) disposed at different times in different memories and storage devices of an electronic device. When read and executed by processor 1302, the instructions cause processing system 1300 to perform operations to execute various aspects of this disclosure.

Although embodiments have been described in the context of a fully functional electronic device, those skilled in the art will understand that various embodiments can be distributed as a program product in various forms. This disclosure applies regardless of the specific type of machine or computer-readable medium used to actually cause the distribution. Further examples of machine and computer-readable media include recordable media such as volatile and non-volatile memory devices 1310, removable disks, hard disk drives, optical disks (e.g., optical disk read-only memory (CD-ROM) and digital universal disks (DVDs)), cloud-based storage devices, and transport media such as digital and analog communication links.

The wireless transceiver 1312 enables the processing system 1300 to transmit data with entities outside the processing system 1300 within the network 1314 via any wireless communication protocol supported by the processing system 1300 and external entities. The wireless transceiver 1312 may include, for example, an integrated circuit (e.g., enabling communication via Bluetooth or Wi-Fi), a network adapter card, or a wireless network interface card.

The techniques described herein can be implemented using software, firmware, hardware, or a combination of these forms. For example, aspects of this disclosure can be implemented using dedicated hardwired (i.e., non-programmable) circuitry in the form of application-specific integrated circuits (ASICs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), etc.

Vertical thrust shaft motor calibration

In some embodiments, the ingestible device may include two or more motors, each with its thrust axis perpendicular to the others. One or more of these motors may be aligned perpendicularly to the capsule body of the ingestible device, i.e., parallel to its z-axis and perpendicular to the longitudinal axis of the ingestible device. The term "thrust axis" here refers to the axis along the thrust direction of a particular motor. As described below, such an implementation may have certain advantages for the purpose of controlling the ingestible device.

Figures 14 to 20 illustrate one such embodiment, showing an embodiment with three motors (“three-motor” embodiment). As shown, the ingestible device 1400 in this embodiment includes a pair of motors 1401A and 1401B positioned at the rear end of the housing 1405, with their thrust axes 1402A and 1402B aligned parallel to the longitudinal central axis (i.e., the main thrust axis) 1403 of the ingestible device 1400. In the illustrated embodiment, each of motors 1401A, 1401B, and 1401C includes a propeller with a single-bladed Archimedean propeller design. However, other embodiments may use different types of propellers, such as multiple individual angled blades, or paddlewheel blades (discussed further below).

The two rear motors 1401A and 1401B have opposite chirality, as in the embodiment described above, to achieve precise yaw control and yaw trim. A third motor (“z-axis motor”) 1401C is mounted at or very close to the center of mass of the intake unit 1400, with its thrust axis 1402C vertically aligned, i.e., parallel to the z-axis and perpendicular to the thrust axes 1402A and 1402B of the other two motors 1401A and 1401B. The thrust axis 1402C of the z-axis motor 1401C can be aligned along the short central axis of the intake unit and through its center of gravity. The illustrated embodiment is advantageous in achieving direct translation of the intake unit 1400 along the z-axis and in achieving trim for active buoyancy control of the intake unit 1400. This embodiment does not require pitch control because direct translation control along the z-axis is available. Note that other embodiments of the ingestible device 1400 may include more than one z-axis motor (i.e., more than one motor whose thrust axis is parallel to the z-axis), and may include fewer or more motors (such as motors 1401A and 1401B) whose thrust axis is parallel to the longitudinal axis 1403, and/or additional motors for yaw control, etc.

A stator 1404 is mounted at the top outlet of the z-axis motor 1401C to reduce eddies in the fluid column generated by the motor, thereby making the motor 1401C more efficient. As shown in Figure 17, the z-axis motor 1401C can be mounted to the inner surface of the housing 1405 via blades 1701, which extend radially outward from the motor 1401C between the outer housing 1702 of the motor 1401C and the inner surface 1703 of the housing 1405 of the ingestible device 1400. The blades 1701 can also serve as a stator at the bottom inlet of the z-axis motor 1401C.

As shown in Figures 15, 16, and 18 through 20, the in-situ device 1400 in the illustrated embodiment also includes a compact cylindrical battery 1406 to provide power to all active components of the in-situ device 1400, including a motor, camera 1412, light source 1413, and radio transceiver (not shown). The illustrated in-situ device 1400 further includes four circuit boards 1407, 1408, 1409, and 1410. The camera 1412 and LED light source 1413 are mounted on circuit board 1407. One or more integrated circuits (e.g., FPGAs and/or ASICs) may be mounted on circuit board 1408 to receive image data from the camera and convert that data into a clean image file. Circuit board 1409 may contain circuitry (e.g., a microcontroller, not shown) to control and/or coordinate various functions of the in-situ device 1400 and the radio transceiver (not shown). Circuit board 1410 may be equipped with higher power circuitry to power motors 1401A, 1401B, and 1401C and/or their onboard controllers (not shown). All circuit boards 1407-1410 are electrically connected directly or indirectly to battery 1406.

T-Motor Example

Figures 21A to 26B relate to another embodiment of an ingestible device for in vivo imaging, which may (but not necessarily) have a motor with its thrust axis oriented perpendicular to the longitudinal axis of the ingestible device for z-axis control. Referring first to Figures 21, 22A, and 22B, examples of the interior of a motor assembly 2300 that could be used in such an ingestible device are shown. Specifically, Figure 21 is a cross-sectional perspective view of the motor assembly 2300, Figure 22A is a side cross-sectional view of the motor assembly 2300 through the center of the fluid channel 2402, and Figure 22B is a top cross-sectional view of the motor assembly 2300 through the center of the fluid channel 2402.

As can be seen, the motor assembly 2300 has a generally T-shaped structure, comprising two sections: a hollow motor housing 2401 and a hollow fluid channel 2402 connected to the motor housing 2401. A battery-powered electric motor is disposed within the motor housing 2401. During operation of the motor driving the propeller 2501, fluid flows through the fluid channel 2402 in either direction. The propeller is rotatably coupled to the electric motor and disposed within the central portion 2405 of the fluid channel 2402. The motor is reversible and therefore can cause the propeller 2501 to rotate clockwise or counterclockwise (from the perspectives in Figures 21 and 22).

When the motor assembly 2300 is mounted in the ingestible device, each open end 2506A or 2506B of the fluid passage 2402 is a fluid inlet/outlet (i.e., an inlet or outlet depending on the direction of fluid flow at any given time). Each inlet/outlet 2506A or 2506B is or is coupled to a corresponding inlet/outlet on the housing (not shown) of the ingestible device, as further described below. In some embodiments, the two inlets/outlets 2506A and 2506B of the motor assembly 2300 face a direction with opposite diameters, as shown in Figures 21 and 22. However, in other embodiments, this may not be the case, as discussed further below.

The motor assembly 2300 includes a propeller 2502 rotatably connected to the body 2601 of a battery-powered electric motor. In the illustrated embodiment, the axis of rotation 2504 of the propeller 2502 is perpendicular to the thrust axis 2505 of the motor, compared to the embodiments discussed above. Furthermore, the propeller 2501 is a paddlewheel propeller, which also differs from the embodiments discussed above. More specifically, the propeller 2501 has a plurality of paddlewheel blades 2605, each having two or more flat drive surfaces (e.g., front and rear), which remain parallel to the axis of rotation of the motor during propeller rotation (the finite thickness of the blades is ignored for illustrative purposes). This contrasts with propellers having multi-angled or helical blades as described above. Paddlewheel propeller configurations such as those shown in Figures 21 and 22 may be advantageous in applications requiring non-relative thrust. That is, angled or helical blades impart a rotational component to the fluid driven by the propeller, whereas paddlewheel propellers do not. In other implementations, it may be desirable to impart a rotational component to the thrust, for example, in cases where it is desirable to use the chirality of one or more motors to manipulate the ingestible device.

As can be seen from Figure 22A, in the illustrated embodiment, the fluid channel 2402 has a generally curved path in a cross-section perpendicular to the rotation axis 2504 of the motor. To generate thrust, the propeller 2501 is vertically offset within the fluid channel 2402 (view from Figure 22). More specifically, in a cross-section perpendicular to the thrust axis 2504, the minimum clearance between the blades 2605 of the propeller 2501 and the lower inner surface 2602 of the fluid channel 2402 is greater than the minimum clearance A between the blades and the upper inner surface 2603 of the fluid channel 2402. This additional space B below the propeller 2501 (as shown in Figure 22) is referred to as the "bypass region". The presence of the bypass region, combined with the viscosity of the fluid within the fluid channel 2402, generates shear forces in the fluid, which result in thrust due to the fluid moving through the bypass region and being ejected through the inlet/outlet 2506A or 2506B of the fluid channel 2402.

In at least one embodiment, dimension A is 0.25 mm and dimension B is 0.5 mm, such that the minimum total gap between the propeller blades and the lower inner surface 2602 of the fluid channel 2402 is (0.25 + 0.5) = 0.75 mm, which is three times the minimum gap (0.25 mm) between the propeller blades and the upper inner surface 2603 of the fluid channel. In such embodiments, the diameter C of the propeller 2501 can be, for example, 3.0 mm, while the diameter D of the fluid channel 2402 is 2.0 mm.

Figures 23A to 23D show different perspective views of the entire exterior of the motor assembly 2300. Note that the motor assembly 2300 may have a slightly modified shape of its housing to allow for closer mating with other similar motor assemblies within an ingestible device, and/or to accommodate its position within the ingestible device, as shown in Figures 24A to 24D (described below). Thus, the motor assembly 2300 is a nominal motor assembly, upon which such slight modifications to the form factor (but not necessarily the function) can be readily generated.

Figures 24A to 24D show different perspective views of a three-motor assembly 2400, which includes three motors based on the nominal motor assembly 2300 discussed above, for generating thrust along three mutually perpendicular coordinate axes (x, y, and z). More specifically, the three-motor assembly 2400 includes an x-motor assembly 2201, a y-motor assembly 2202, and a z-motor assembly 2203, each of which is identical or substantially similar to the nominal motor assembly 2300 discussed above. Each of these motors is so named based on the coordinate axis along which it generates thrust. A portion of the housing adjacent to each inlet/outlet is also shown to provide context regarding how the motor assemblies are mounted within the ingestible device.

Figures 25A and 25B show two different perspective exterior views of an ingestible device 2500 that may include a three-motor assembly 2400. Figures 26A and 26B show two perspective views of the ingestible device 2500 corresponding to Figures 25A and 25B, respectively, but with half of the housing removed to make the three-motor assembly 2400 visible, and with certain components not closely related to this description (e.g., circuit boards, batteries, and electrical connectors) also removed. Depicted in these figures are the Z-shaped motor inlet/outlet 2102, the first X-shaped motor inlet/outlet 2103, the second X-shaped motor inlet/outlet 2105, and the Y-shaped motor inlet/outlet 2104. The same Z-shaped motor inlet/outlet 2102 and thrust motor inlet/outlet 2103 are visible in Figure 21B. That is, inlet/outlet 2103 and inlet/outlet 2105 form opposite ends of a thrust motor assembly (not shown). Although not all inlets/outlets are visible in these views, each inlet/outlet has a paired inlet/outlet on the opposite side of its corresponding motor assembly, as described above and shown in Figures 21 and 22. Battery holder 2204 is also shown in Figures 26A and 26B.

As described above, in some embodiments, the two inlets/outlets of any particular motor assembly may face directions with opposite diameters, as shown in Figures 21 and 22. This is the case for the y motor assembly 2202 and z motor assembly 2203 discussed above. However, in some embodiments, this may not be the case for each motor assembly in the ingestible device, such as the x motor assembly 2201. More specifically, as shown in Figures 24A through 24D, one inlet/outlet 2105 of the x motor assembly 2201 faces directly towards the rear of the ingestible device, while the other inlet/outlet 2103 of the x motor assembly 2201 faces upward and forward at an acute angle. In some embodiments, this difference in inlet/outlet angle can be used to provide additional controllability of the ingestible device (e.g., pitch control).

Examples of some embodiments

The one or more embodiments disclosed above can be summarized as follows [The following paragraphs reflect only the claims and are strictly included for legal reasons. Please skip to the "Claims" section below.]

1. An ingestible imaging device, comprising: a housing; an imaging device disposed within the housing; and a plurality of motors for providing propulsion to the ingestible imaging device when it is immersed in a fluid environment within a living body, wherein at least two of the plurality of motors have thrust axes perpendicular to each other.

2. The ingestible imaging device according to Example 1, wherein the plurality of motors includes three motors.

3. The ingestible imaging device according to Example 1 or Example 2, wherein the housing has an elongated capsule shape having a longitudinal central axis, and wherein the plurality of motors includes a first motor and a second motor, the first motor having a thrust axis parallel to the longitudinal central axis of the housing, and the second motor having a thrust axis perpendicular to the longitudinal central axis of the housing.

4. The in-feed imaging device according to any one of Examples 1 to 3, wherein the second motor is mounted at the center of mass of the in-feed imaging device.

5. The in-situ imaging device according to any one of Examples 1 to 4, wherein the housing of the in-situ imaging device has a second central axis perpendicular to the longitudinal central axis of the housing, and wherein the thrust axis of the second motor is aligned along the second central axis.

6. The ingestible imaging device according to any one of Examples 1 to 5, wherein the second motor is operable to provide active buoyancy trim to the ingestible imaging device when it is immersed in a fluid environment within a living body.

7. The ingestible imaging device according to any one of Examples 1 to 6, wherein the plurality of motors further includes a third motor having a third thrust axis parallel to the longitudinal central axis of the housing.

8. The ingestible imaging device according to any of Examples 1 to 7, wherein at least two of the plurality of motors are reversible so as to each provide bidirectional thrust capability.

9. The ingestible imaging device according to any one of Examples 1 to 8 further includes a stator located at a fluid outlet associated with a second motor.

10. The ingestible imaging device according to any one of Examples 1 to 9, wherein at least one of the plurality of motors includes a propeller having a rotation axis perpendicular to the thrust axis of the motor.

11. The ingestible imaging device according to any one of Examples 1 to 10, wherein each of the plurality of motors includes a propeller having a rotation axis perpendicular to the thrust axis of the motor.

12. The ingestible imaging apparatus according to any of Examples 1 to 11, wherein each of the plurality of motors includes a propeller configured to rotate about a rotation axis, the propeller having a plurality of blades, each of the plurality of blades having a drive surface that remains parallel to the rotation axis of the motor during rotation of the propeller.

13. The ingestible imaging device according to any of Examples 1 to 12, wherein each of the plurality of motors provides bidirectional thrust.

14. The ingestible imaging apparatus according to any of Examples 1 to 13, wherein each of the plurality of motors includes a propeller mounted within a channel for carrying fluid, the propeller having a rotation axis perpendicular to the thrust axis of the motor, the propeller being spatially offset relative to the geometric center of the channel in a cross-sectional plane perpendicular to the rotation axis.

15. An ingestible imaging apparatus according to any of Examples 1 to 14, wherein the propeller has an axis of rotation and wherein the channel has a curved U-shaped path in a cross-sectional plane perpendicular to the axis of rotation.

16. The ingestible imaging apparatus according to any of Examples 1 to 15, wherein each of the plurality of motors includes a propeller mounted within a channel for carrying fluid, the propeller having at least one blade and a rotation axis perpendicular to the thrust axis of the motor, and wherein: in a cross-sectional plane perpendicular to the thrust axis, the minimum clearance between at least one blade and the lower inner surface of the channel is greater than the minimum clearance between at least one blade and the upper inner surface of the channel.

17. The ingestible imaging device according to any of Examples 1 to 16, wherein, in a cross-sectional plane perpendicular to the thrust axis, the minimum clearance between at least one blade and the lower inner surface of the channel is approximately three times the minimum clearance between at least one blade and the upper inner surface of the channel.

18. An ingestible imaging device according to any of Examples 1 to 17, wherein the channel is shaped such that, during operation of the motor, fluid moving through the channel takes a curved path through the motor in a cross-sectional plane perpendicular to the axis of rotation.

19. The ingestible imaging device according to any of Examples 1 to 18, wherein the plurality of motors includes three motors having thrust axes that are perpendicular to each other.

20. An ingestible imaging device, comprising: a housing having an elongated capsule shape and a longitudinal central axis defining the longest dimension of the housing; a light source disposed within the housing; an imaging device disposed within the housing; and a first motor, a second motor, and a third motor disposed within the housing to provide propulsion to the ingestible imaging device when it is immersed in a fluid environment within a living body, each of the first motor, the second motor, and the third motor having a propeller having a rotation axis and a thrust axis perpendicular to the rotation axis, wherein the thrust axis of the first motor is parallel to the longitudinal central axis of the housing, and the thrust axis of the second motor is perpendicular to the longitudinal central axis of the housing.

21. The ingestible imaging device according to Example 20, wherein the thrust axis of the third motor is perpendicular to the longitudinal central axis of the housing and the thrust axis of the second motor.

22. The ingestible imaging apparatus according to Example 20 or Example 21, wherein the propeller of each of the first motor, the second motor and the third motor has at least one blade, the driving surface of the at least one blade remaining parallel to the axis of rotation of the motor during rotation of the propeller.

23. The ingestible imaging apparatus according to any of Examples 20 to 22, wherein each of the first motor, the second motor and the third motor includes a propeller mounted in a channel for carrying fluid, the propeller having at least one blade and a rotation axis perpendicular to the thrust axis of the motor, and wherein: in a cross-sectional plane perpendicular to the thrust axis, the minimum clearance between at least one blade and the lower inner surface of the channel is greater than the minimum clearance between at least one blade and the upper inner surface of the channel.

24. An ingestible imaging device, comprising: a housing having an elongated capsule shape and a longitudinal central axis defining the longest dimension of the housing; a light source disposed within the housing; an imaging device disposed within the housing; and a first motor, a second motor, and a third motor disposed within the housing to provide propulsion to the ingestible imaging device when it is immersed in a fluid environment within a living body, wherein the thrust axis of the first motor is parallel to the longitudinal central axis of the housing, and the thrust axis of the second motor is perpendicular to the longitudinal central axis of the housing.

25. The ingestible imaging device according to Example 24, wherein each of the first motor, the second motor and the third motor has a propeller having a rotation axis and a thrust axis perpendicular to the rotation axis.

26. The ingestible imaging device according to Example 24 or Example 25, wherein the thrust axis of the third motor is perpendicular to the longitudinal central axis of the housing and the thrust axis of the second motor.

27. The ingestible imaging apparatus according to any of Examples 24 to 26, wherein the propeller of each of the first motor, the second motor and the third motor has at least one blade, the driving surface of which remains parallel to the axis of rotation of the motor during the rotation of the propeller.

28. The ingestible imaging apparatus according to any of Examples 24 to 27, wherein each of the first motor, the second motor and the third motor includes a propeller mounted in a channel for carrying fluid, the propeller having at least one blade and a rotation axis perpendicular to the thrust axis of the motor, and wherein: in a cross-sectional plane perpendicular to the thrust axis, the minimum clearance between at least one blade and the lower inner surface of the channel is greater than the minimum clearance between at least one blade and the upper inner surface of the channel.

Any or all of the features and functions described above may be combined with each other unless otherwise stated above or any such embodiments are incompatible due to their function or structure, as will be apparent to those skilled in the art. Unless contrary to physical possibility, it is foreseeable that (i) the methods/steps described herein may be performed in any order and/or in any combination, and (ii) the components of the various embodiments may be combined in any manner.

Although the subject matter is described in language specific to structural features and/or actions, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or actions described above. Rather, the specific features and actions described above are disclosed as examples of implementing the claims, and other equivalent features and actions are intended to be within the scope of the claims.