Abstract: Systems and methods for limiting rotation of a supported object about an axis of rotation are provided. A system as disclosed includes a stop system that engages at a selected amount of rotation about an axis of rotation to provide a balanced force countering further rotation. The stop system includes one or more pairs of stop mechanisms, with one stop mechanism in a pair disposed to act from a first side of the axis of rotation, and a second stop mechanism in the pair disposed to act from a second side of the axis of rotation. Each stop mechanism can include stops that engage a flexure at a selected amount of rotation.

Abstract: Systems and methods for providing a broadband antenna are disclosed. The antenna can include a current sheet array having a plurality of antenna elements. Each antenna element includes dipole arms. The dipole arms can be configured as first and second dipole arm pairs for transmitting or receiving signals of different polarizations. A resistive-capacitive (RC) loading structure is provided for each antenna element, in a layer between the antenna elements and a surface of an antenna substrate. Each RC loading structure includes a set of conductive surfaces and a set of resistive surfaces. A dielectric layer separates the RC loading structure elements from the dipole arms.

Abstract: Multi-spectral methods and systems for the day and night remote sensing (detection, identification, and quantification) of greenhouse gas emission sources from space are provided. The sensor system includes a telescope assembly that passively collects light from an observation area and directs that light through spectral, optical filters and to a sensor array having a plurality of rows and columns of pixels. Different groups of sensor array pixel rows are aligned to receive light that has passed through different optical filters. The filters have passbands corresponding to the reflective and emissive bands of gases of interest, as well as associated reflective and emissive reference bands, and broadband spectral bands. A set of image data frames is obtained as the field of view of the sensor system moves over an observation area and an aggregate image showing locations of detected gas emissions is generated using the collected data.

Abstract: Flexure structures, assemblies incorporating flexure structures, and methods utilizing flexure structures to support objects are provided. A flexure structure as disclosed can be formed monolithically from a single piece of material, includes a center aperture to accommodate at least portions of other elements or structures, allows for rotation of a supported object in two axes with very little translational movement of the supported object, provides mounting fixtures on opposite sides of the flexure structure, and has a relatively high load capacity. Flexure structures include base mounts that can each be joined to a first side of an interconnect structure by flexure blades, and object mounts that are each joined to a second side of the interconnect structure by flexure blades. The flexure structure can be a generally annular structure, with the center aperture formed or defined at least in part by the interconnect structure.

Abstract: Systems and methods for providing thermal systems having one or more radiators that each incorporate one or more heat pipe matrices are provided. Each heat pipe matrix includes at least one spreader heat pipe element and a plurality of lateral heat pipe elements. The lateral heat pipe elements can extend in a direction that is generally transverse to a direction in which the spreader heat pipe element extends. Each lateral heat pipe element includes a portion that is thermally coupled and parallel to a portion of at least one spreader heat pipe element. Multiple heat pipe matrices can be thermally coupled to one another by jumper heat pipes to form heat pipe networks.

Abstract: Systems and methods for pointing a high gain antenna or other directional instrument connected to a platform by a gimbal are provided. A control system as disclosed can include a flight computer having a processor for executing software and a motor control board having a controller for implementing at least portions of a control algorithm. The software executed by the processor generates pointing commands and implements a Kalman filter included in a feedback loop in the form of a linear Kalman filter disturbance estimator of the control algorithm implemented by the controller. The control algorithm can further implement a proportional control position loop and a proportional control rate loop. Each axis of the gimbal is provided with an instance of the control algorithm and the Kalman filter. Moreover, the processor can be operated at a rate that is less than a rate at which the controller is operated.

Abstract: A multiple functional instrument is provided. The instrument includes an optical autocovariance function interferometer that can feature multiple fields of view to detect winds in the atmosphere. The instrument can include an infrared camera to detect atmospheric temperatures and the presence of clouds, and a detector assembly that detects the polarization of light returned to the interferometer. Data collected by the instrument can be provided to a deep and reinforcement learning algorithm for real-time prediction of clear air turbulence and other wind-based aviation safety phenomena. Moreover, predicted and actual conditions can be correlated and used to train a deep learning algorithm to enable more accurate predictions. The instrument can be carried by an aircraft or other platform and operated to detect clear air turbulence or other atmospheric phenomena, and to provide instructions regarding flight parameters including wind-aided navigation in order to minimize the effect of predicted turbulence.

Abstract: Systems and methods for providing an electrically small antenna are provided. The antenna can include an arm or a pair of arms disposed on a surface of a substrate. The substrate and the arm or arms are generally disposed in an aperture or volume formed in a housing. A capacitive gap is provided between the arm and the housing, or between the arms. Where the antenna includes a pair of arms, each arm generally includes a main portion disposed on the first surface of the substrate and a perpendicular portion that extends from the first surface of a substrate towards a ground plane on a second surface of the substrate. The perpendicular portions of the arms face one another. In addition, the main portions of the arms can be tapered in plan view. A ground plane can be provided on the second surface side of the substrate.

Abstract: Suspension system structures and methods are provided. A system as disclosed includes a supported object that is mounted to a post by a first two axis gimbal. The system also includes a reaction mass that is mounted to the post by a second two axis gimbal. The supported object and the reaction mass are connected to one another by a drive assembly. The drive assembly transfers a rotation of the reaction mass about either of the two axes in a first direction to a rotation of the supported object about a parallel axis in an opposite direction.

Abstract: Systems and methods for providing a high gain antenna are disclosed. The antenna can include an array of active antenna elements disposed on a first side of a first circuit board. The active antenna elements are grouped into a number of super elements. Each super element occupies at least a portion of an outside edge of an area containing the active antenna elements. Passive antenna elements can be disposed so as to surround the area containing the active antenna elements. Passive circuit components can be disposed on a second side or on an intermediate layer of the first circuit board. Active circuit components can be disposed on a second circuit board. The active components can be supplied with power and control signals. The first and second circuit boards can be held together by a housing. The antenna can be configured as conformal array antennas.

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.