The Charles Stark Draper Laboratory, Inc.

Other

William M Johnson

Edward Bernardon

Howard Musoff

Lewis R Andrews

Marc Steven Weinberg

Raymond Carroll

Jerold Philip Gilmore

Cornelius J Dennehy

Joe P Reo

Darryl G Sargent

A communication system for providing world-wide, mobile Internet communication to a plurality of users and a method therefore. The system includes ground-based, multi-channel, radio frequency transmitting and receiving broadcasting grids that are capable of providing content to multiple users via cell towers and low-altitude, optical transmitting and receiving satellites that are in optical communication with the ground-based, multi-channel, RF transmitting and receiving broadcasting grids. The method includes transmitting optical and/or RF signals between at least one of the ground-based, multi-channel, RF transmitting and receiving broadcasting grids and at least one of the low-altitude, optical transmitting and receiving satellites.

World-wide, wide-band, low-latency, mobile internet and system therefor

A method of controlling inertial attitude of an artificial satellite in order to perform a navigation function and to maximize terrestrial coverage of the Earth by the satellite. The method includes deploying the artificial satellite in an orbit about the poles of the Earth; applying gyroscopic precession to the artificial satellite spin axis to precess and maintain the satellite near the ecliptic pole; deploying the artificial satellite so that the spin axis is initially perpendicular to or substantially perpendicular to sun lines; and applying gyroscopic precession to the artificial satellite spin axis to precess the spin axis away from an initial deployed attitude at a selectively-variable precession rate and to maintain the spin axis perpendicular to or substantially perpendicular to the sun lines.

Method and computer program product for controlling inertial attitude of an artificial satellite by applying gyroscopic precession to maintain the spin axis perpendicular to sun lines

A method of and apparatus for determining and controlling the inertial attitude of a spinning artificial satellite without using a suite of inertial gyroscopes. The method and apparatus operate by tracking three astronomical objects near the Earth's ecliptic pole and the satellite's and/or star tracker's spin axis and processing the track information. The method and apparatus include steps and means for selecting preferably three astronomical objects using a histogram method and determining a square of a first radius (R) of a track of a first astronomical object; determining a square of a second radius (R) of a track of a second astronomical object; determining a square of a third radius (R) of a track of a third astronomical object; determining the inertial attitude of the spin axis using the squares of the first, second, and third radii (R, R, and R) to calculate pitch, yaw, and roll rate; determining a change in the pitch and yaw of the artificial satellite; and controlling on-board generated current flow to various orthogonally-disposed current-carrying loops to act against the Earth's magnetic field and to apply gyroscopic precession to the spinning satellite to correct and maintain its optimum inertial attitude.

System for determing and controlling inertial attitude, for navigation, and for pointing and/or tracking for an artificial satellite employing and optical sensor and a counter-rotational optical mirror, and terrestrial-based testing system for assessing inertial attitude functions of an artificial satellite

Method of determining and controlling the inertial attitude of a spinning, artificial satellite and systems therefor

A spectroscopy system uses a probe laser beam and an opposing excitation laser beam, i.e., running opposite to a direction of the probe laser beam, but transmitted co-linearly with one another along a same optical path. A thermal lens effect acting on the probe laser beam allows for controlling alignment of the two laser beams and allows for supplementary measurements of parameters for the spectroscopy system based on geometric analysis of detected image signals. The alignment of the two laser beams is controlled by detection of the probe laser beam with respect to the effects of the excitation laser beam on a medium through which the two laser beams are passing.

Systems and methods for spectroscopy using opposing laser beams

The present invention provides methods of and apparatus for determining the inertial attitude of an aerospace vehicle. In one embodiment, the invention provides a rotational astronomical object-sighting concept to determine the inertial attitude of an axis of the aerospace vehicle without the star identification or dragback. In another embodiment, the invention provides an attitude measurement apparatus comprising a high sensitivity optical sensor and a low power inertial sensor.

Miniature attitude sensing suite

The present invention provides a drug delivery system containing a pharmaceutically active core and a coating of the core. The coating is comprised of a an emulsifier and a wax. The coating provides rapid dissolution and enhanced long-term stability for the pharmaceutically active ingredient.

Tastemasked pharmaceutical system

A coarse/fine alignment system and method for boresighting high energy, laser pulses onto ballistic missiles in their boost phase. A ground based, common optical aperture laser separator, a mosaic array sensor, and a controller are cooperative to align bursts of light of a ground based laser with a beacon laser of a satellite reciprocally along an uplink therebetween so that the wavelength of the bursts and the wavelength of the beacon laser are the same wavelength. The principle of propagation reciprocity operates to provide ultra high alignment accuracy. Light provided along the reciprocal optical path provides boresight blooming autocollimation and an ultra high pointing angle resolution. An inertial target tracker provides spacial coordinates and angular rate coordinates of remote targets sited by the tracker. A single mosaic array sensor and associated systems are operative to provide pseudo-star, target spot, and other sensor spots compensated for vibration and other noise phenomena. Shared, sensor spot narrow bandwidth and a common wavelength contribute to a high measure of noise immunity. Beam expander/compressor magnification makes possible ultra high accuracy position and angular rate inertial frame coordinate determinations from the vibrationally stabilized spots of pixel size. A tracker mission mirror controllably aligns a high energy laser light from a destination to a target.

Ballistic missile boresight and inertial tracking system and method

An attitude sensing system utilizing simplified techniques and apparatus includes a Kalman filter which receives signals from an inertial measurement unit, a GPS receiver, and an integrated optical assembly. The output vector of the filter includes estimates of attitude misalignments and estimates of gyro drifts corresponding to the axes of the inertial measurement unit. The optical assembly includes a sensor array providing signals to the filter representing detection of the Earth's horizon or the center of the Sun. More particularly, a local vertical vector, computed from fore and aft detections of the Earth's horizon, is used in combination with GPS received signals to initially determine attitude by means of gyrocompassing. This attitude information is thereafter maintained by the inertial measurement unit and azimuth error resulting from drift of the inertial measurement unit and the initial gyrocompassing error is corrected by detections of the Earth's horizon and the Sun. The integrated optical assembly, used to detect the locations of both the Sun and Earth relative to the satellite, eliminates a need for separate apparatus dedicated to each sensing function. Moreover, the GPS receiver eliminates the need for ground tracking apparatus by providing the satellite ephemerides (including orbital pitch rate used in gyrocompassing) for use by the filter, rendering the attitude sensing system substantially autonomous. Additionally, the GPS receiver, in combination with the Sun and Earth detections, eliminates the need for a complex star tracker by providing an accurate inertial frame of reference.

Apparatus and method for autonomous satellite attitude sensing

A space-based command guidance controller and controlled deliverable traveling at speeds of about Mach five are cooperative to cause the deliverable to follow a coherent designator beam controlled by the space-based command guidance controller to be delivered to a target location, eventually designated by the beam along an over-the-horizon trajectory, and into a target thereat with surgical-like precision. The command guidance controller includes an optical tracker and coherent designator laser assembly and an inertially-stabilized tracker that are cooperative to produce a command guidance signal representative of that controlled deliverable maneuver that enables the controlled deliverable, upon the execution thereof, to conform its trajectory to the intended trajectory, and eventually, to impact the intended target. The controlled deliverable includes an autopilot that executes the maneuver represented by the command guidance signal in order to bring the controlled deliverable into local conformance to the intended trajectory. The controlled deliverable includes an optical roll sensor having a negligible scale-factor-error. The intended target location may include a static and/or a dynamic target object.

Ballistic missile remote targeting system and method

One or more strap-down star tracker modules and a strap-down gyro module cooperate to provide a high-performance and low-cost inertial guidance system especially well suited for ballistic missiles. The one or more star tracker modules include an alignment laser that cooperates with one or more gyro module autocollimation mirrors to measure three-axis bending and twist between the one or more strap-down star tracker modules and the strap-down gyro module. The one or more strap-down star tracker modules and the strap-down gyro module respectively determine inertial angle independently of one another. The strap-down gyro module is compensated for gyro drift whenever any difference remains between the inertial angle measured thereby and the same inertial angle measured by the one or more star tracker modules after isolating the contribution thereto of the measured three-axis bending and twist. Ring lasers are exemplary of the gyros of the strap-down gyro module, and an optical tracker that includes a beam expander/compressor telescope assembly and a high-bandwidth mosaic array sensor having a multi-spot tracking capability is exemplary of the one or more strap-down star tracker modules.

High-performance, low-cost inertial guidance system

Rotatable warning sign for vehicles

Apparatus and method are disclosed enabling to register vectors respectively representative of directed energy pointing direction and targeted object pointing direction to allow rapid re-targeting boresight alignment transfer of a space-based neutral particle beam to targeted ballistic missile trajectories independently of relative reference frame vector measurement uncertainty arising from platform vibration and, among other things, space-noise.

Rapid re-targeting, space-based, boresight alignment system and method

A body portion is supported in upright position by a support stem and has wind propelling blades arranged to rotatably drive the body portion when subjected to air currents. The body portion has front and rear surfaces one of which may support a rear view mirror and the other of which may support a reflector. The body portion has a lock nut for holding it stationary on the stem, for allowing rotation thereof when released. The body portion has forward and rearward as well as lateral adjustable positioning on the stem, and the stem has lateral positioning on a bracket that mounts it on a vehicle.

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Sudbury, MA, United States of America

William M Johnson