Abstract: Systems and methods for providing a solar cell array with a reduced magnetic field are provided. The systems include a plurality of solar cells arrayed on a first surface side of a substrate. The solar cells are electrically connected to one another in series by a first conductor structure at least partially disposed on the first surface side of the substrate, forming a solar cell or supply circuit. A second conductor structure in series with the solar cell circuit is at least partially disposed on the second surface side of the substrate, forming a return harness. The supply circuit and the return harness define current paths that are opposite one another, and that are separated from one another by the substrate. The first and second conductor structures can be formed from conductive traces on the first and second sides respectively of the substrate.

Abstract: A method and apparatus of objective assessment of images captured from a human gastrointestinal (GI) tract are disclosed. According to this method, one or more images captured using an endoscope when the endoscope is inside the human gastrointestinal (GI) tract are received. Whether there is any specific target object is checked. When one or more specific target objects in the images are detected: areas of the specific target objects in the images are determined; an objective assessment score is derived based on the areas of the specific target objects in a substantial number of images from the images; where the step of detecting the specific target objects is performed using an artificial intelligence process.

Abstract: A robotic cleaner includes a housing, a suction conduit with an opening, and a leading roller mounted in front of a brush roll. An inter-roller air passageway may be defined between the leading roller and the brush roll wherein the lower portion of the leading roller is exposed to a flow path to the suction conduit and an upper portion of the leading roller is outside of the flow path. Optionally, a combing unit includes a plurality of combing protrusions extending into the leading roller and having leading edges not aligned with a center of the leading roller. Optionally, a sealing strip is located along a rear side of the opening and along a portion of left and right sides of the opening. The underside may define side edge vacuum passageways extending from the sides of the housing partially between the leading roller and the sealing strip towards the opening.

Abstract: Techniques for minimizing diurnal temperature variation of a radiator of a spacecraft are disclosed. In one aspect, a spacecraft includes a body, a radiator panel, and a heat dissipating unit thermally coupled with the radiator panel. The spacecraft is configured to operate in an orbital plane, and has a yaw axis within the orbital plane and directed from a spacecraft coordinate system origin toward nadir, a pitch axis orthogonal to the orbital plane, and a roll axis orthogonal to the pitch axis and the yaw axis. The radiator panel includes a surface area external to a body of the spacecraft, a first portion of the surface area facing a first direction that is substantially parallel to the roll axis, and a second portion of the surface area facing a second direction that has a substantial component parallel to the yaw axis.

Abstract: A spacecraft includes a semi-rigid solar array and a main body structure, the main body structure configured as a convex polyhedron and including an aft and a forward face disposed opposite to the aft face and at least four side faces disposed between and approximately orthogonal to the aft face and the forward face. The solar array includes a number of panels linked together with flexible couplings. In an undeployed configuration, panels of the solar array cover at least two adjacent side faces, the flexible couplings providing an articulable joint approximately aligned with a line along which the two adjacent side faces are joined and connecting a first panel of the solar array and a second panel of the solar array, the first panel being proximal to a first side face and the second panel being proximal to a second side face.

Abstract: A spacecraft includes an additive manufacturing (A/M) subsystem and one or both of a thermal control arrangement and a contamination control arrangement. The A/M subsystem includes an A/M tool, feedstock and a workpiece and is configured to additively manufacture the workpiece using material from the feedstock. The thermal control arrangement is operable, in an on-orbit space environment characterized by near vacuum pressure and near zero-g force, to maintain temperature of at least one of the A/M tool, the feedstock, and the workpiece within respective specified ranges. The contamination control arrangement is operable, in the on-orbit space environment, to control outgassing of volatile organic compounds (VOCs).

Abstract: A spacecraft includes a propulsion subsystem including at least two electric thrusters, an electrical interface assembly that couples electrical conductors from the thrusters to a spacecraft harness, a pneumatic interface assembly that controls flow rate of propellant to the thrusters and a thruster support module (TSM) including a pointing arrangement and a mounting arrangement. A proximal portion of the mounting arrangement is coupled with a distal portion of the pointing arrangement; the at least two electric thrusters are disposed on a distal portion of the mounting arrangement; the electrical interface assembly and the pneumatic interface assembly are disposed on the proximal portion of the mounting arrangement. The mounting arrangement is configured to limit heat transfer between the thrusters and (b) one or more of the proximal portion of the mounting arrangement, the electrical interface assembly and the pneumatic interface assembly.

Abstract: A spacecraft includes a propulsion system including an inert gas stored in a set of pressurant tanks, one or more electric thrusters operable with the inert gas, one or more cold gas thrusters operable with the inert gas; and a pneumatic arrangement including commandable valves.

Abstract: Techniques for minimizing diurnal temperature variation of a radiator of a spacecraft are disclosed. In one aspect, a spacecraft includes a body, a radiator panel, and a heat dissipating unit thermally coupled with the radiator panel. The spacecraft is configured to operate in an orbital plane, and has a yaw axis within the orbital plane and directed from a spacecraft coordinate system origin toward nadir, a pitch axis orthogonal to the orbital plane, and a roll axis orthogonal to the pitch axis and the yaw axis. The radiator panel includes a surface area external to a body of the spacecraft, a first portion of the surface area facing a first direction that is substantially parallel to the roll axis, and a second portion of the surface area facing a second direction that has a substantial component parallel to the yaw axis.

Abstract: A spacecraft includes a propulsion system that includes one or more pressurant tanks configured to store an inert gas at a high pressure, one or more propellant tanks configured to store liquid propellant at an intermediate pressure, electric thrusters operable with the inert gas at a low pressure and pneumatically coupled with the one or more pressurant tanks by way of a first pressure regulator, and chemical thrusters operable with the liquid propellant. The inert gas is one or a mixture of two or more of xenon, argon and krypton. At least a portion of the liquid propellant is stored in at least one of the propellant tanks, the propellant tank including an ullage volume pneumatically coupled with at least one of the pressurant tanks by way of a second pressure regulator having an output set to the intermediate pressure and the ullage volume is pressurized by the inert gas.

Abstract: A spacecraft includes an additive manufacturing (A/M) subsystem and one or both of a thermal control arrangement and a contamination control arrangement. The A/M subsystem includes an A/M tool, feedstock and a workpiece and is configured to additively manufacture the workpiece using material from the feedstock. The thermal control arrangement is operable, in an on-orbit space environment characterized by near vacuum pressure and near zero-g force, to maintain temperature of at least one of the A/M tool, the feedstock, and the workpiece within respective specified ranges. The contamination control arrangement is operable, in the on-orbit space environment, to control outgassing of volatile organic compounds (VOCs).

Abstract: A first spacecraft includes a first fluid storage arrangement and a fluid flow metering arrangement including a holding tank coupled with the first fluid storage arrangement, a flow meter disposed proximate to the holding tank, and an active thermal control arrangement controlling the temperature of the flow meter and the holding tank. The first spacecraft is configured to service a second spacecraft, the second spacecraft including a second fluid storage arrangement, by transferring one or both of a propellant and a pressurant from the first fluid storage arrangement to the holding tank, and from the holding tank, through the flow meter, to the second fluid storage arrangement.

Abstract: A spacecraft includes a structural interface adapter for mating to a launch vehicle, an aft surface disposed proximate thereto, and a forward surface disposed opposite thereto, a main body structure, including a plurality of sidewalls, disposed between the aft surface and the forward surface and a plurality of unfurlable antenna reflectors. At least one unfurlable antenna reflector is configured to be illuminated, in an on-orbit configuration, by a respective feed array. The spacecraft is reconfigurable from a launch configuration to the on-orbit configuration. In the launch configuration, the at least one unfurlable antenna reflector is disposed, undeployed, forward of the respective feed array, proximate to and outboard of one of the plurality of sidewalls. In the on-orbit configuration, the forward surface is substantially earth-facing and the at least one unfurlable antenna reflector is disposed, deployed, so as to be earth-facing from a position aft of the respective feed array.

Abstract: A spacecraft includes a body, a plurality of separate units, and a first auxiliary radiator panel. The body includes a plurality of sidewalls, at least a first sidewall of the plurality of sidewalls including an outboard-facing radiator surface having optical solar reflectors disposed thereon. A first subset of the plurality of units is thermally coupled with the outboard-facing radiator surface of the first sidewall. A second subset of the plurality of units is thermally coupled with the first auxiliary radiator panel and is isolated from at least conductive thermal heat transfer with the outboard-facing radiator surface of the first sidewall. The first subset of units is spatially proximate to the second subset of units and is configured to operate in a first temperature range. The second subset of units is configured to operate in a second temperature range, the second temperature range being different from the first temperature range.

Abstract: Techniques for articulating a sunshield to shade portions of a spacecraft are disclosed. In one aspect, a spacecraft includes a body and an articulable sunshield. The spacecraft is configured to operate in an orbital plane, such that the spacecraft has a yaw axis within the orbital plane and directed from a spacecraft coordinate system origin toward nadir, a pitch axis orthogonal to the orbital plane and passing through the spacecraft coordinate system origin, and a roll axis orthogonal to the pitch axis and the yaw axis and passing through the spacecraft coordinate system origin. The sunshield is configured to rotate about an axis substantially parallel to the pitch axis such that a selected location of an exterior portion of the body is shaded from the Sun by a surface of the sunshield irrespective of seasonal and diurnal variations in orientation of the spacecraft with respect to the Sun.

Abstract: A multi-beam antenna (MBA) system for a spacecraft, the MBA system including a reflector and a feed array of radiating feed elements configured as a phased array and illuminating the reflector. The feed array includes a plurality of interchangeable modules. Each of the plurality of interchangeable modules includes a distal mounting panel and a proximal mounting panel, and at least six feed array elements. Each feed array element is electrically coupled with a respective amplifier and mechanically coupled with an exterior surface of the distal mounting panel. The respective amplifiers are thermally coupled with the proximal mounting panel and are mechanically coupled to an interior surface of the distal mounting panel and an exterior surface of the proximal mounting panel. An interior surface of the proximal mounting panel of each interchangeable module is mechanically and thermally coupled with a back plate.

Abstract: A spacecraft includes a spacecraft main body, including payload equipment disposed on an inner panel surface of at least one radiator panel, the at least one radiator panel having an exterior-facing outer panel surface. The spacecraft includes at least one electric thruster disposed proximate to an aft facing panel of the spacecraft main body. The at least one electric thruster is thermally coupled with the at least one radiator panel by way of a thermally conductive path.

Abstract: A spacecraft payload subsystem includes a tracking receiver, an input multiplexer, an antenna pointing mechanism (APM) controller and a plurality of antenna reflectors. Each antenna reflector is mechanically coupled with a respective APM, and illuminated by a respective tracking feed element. Each respective tracking feed element is configured to receive an uplink beacon signal from the ground by way of one of the antenna reflectors and is coupled, by way of a respective pseudo-monopulse (PSM) coupler and the input multiplexer, to the tracking receiver. The tracking receiver is configured to receive multiplexed signals from the PSM couplers by way of the input multiplexer and output corresponding pointing error information to the APM controller. The APM controller is configured to send commands to one or more of the APMs. Each APM is configured to point a respective antenna reflector in response to the commands.

Abstract: A modularized feed array arrangement includes a plurality of radio frequency (RF) radiating elements, a plurality of waveguides positioned inboard of the plurality of RF radiating elements, each RF radiating element being electrically coupled with an outboard portion of one or more of the waveguides; and a plurality of modules, each module including a plurality of RF switches, a plurality of amplifiers, and a manifold panel that includes a plurality of RF choke joints. An inboard portion of each RF switch is electrically coupled with a respective amplifier. Each RF choke joint includes a proximal portion electrically coupled with an outboard portion of a respective one of the RF switches and a distal portion electrically coupled with an inboard portion of a respective one of the waveguides.

Abstract: A spacecraft includes a structural interface adapter for mating to a launch vehicle, an aft surface disposed proximate thereto, and a forward surface disposed opposite thereto, a main body structure, including a plurality of sidewalls, disposed between the aft surface and the forward surface and a plurality of unfurlable antenna reflectors. At least one unfurlable antenna reflector is configured to be illuminated, in an on-orbit configuration, by a respective feed array. The spacecraft is reconfigurable from a launch configuration to the on-orbit configuration. In the launch configuration, the at least one unfurlable antenna reflector is disposed, undeployed, forward of the respective feed array, proximate to and outboard of one of the plurality of sidewalls. In the on-orbit configuration, the forward surface is substantially earth-facing and the at least one unfurlable antenna reflector is disposed, deployed, so as to be earth-facing from a position aft of the respective feed array.