Visualization of Field of View Obstruction by an Ellipsoid

US Patent Issued Inventors
9,449,424 B2 9.20.2016 Frank Stoner and Patrick Cozzi

Methods, systems, and devices for the visualization of the region of a 3-dimensional space obstructed from a viewing location by an ellipsoid are disclosed. In an embodiment, the obstructed region may be defined from primitive elements which are combined using Boolean operations. The primitive elements chosen may be represented using both implicit functions and/or parametric surfaces. In an embodiment, the implicit function representation may be used to quickly determine points on candidate surfaces which may be obstructed from view. In an embodiment, the parametric representation may be used to provide ray-surface intersection solutions enabling visualization of the boundary surface of the obstruction region.

System and method for determining earth-fixed trajectory launching from within a specified area

US Patent Issued Inventor
8,718,920 5.6.2014 Dr. Sergei Tanygin

This patent discloses a method and apparatus for minimizing close approaches between spacecraft being launched from anywhere within a specified area and other objects in space during the launch and early deployment phase of their lifetime. The method defines a launch window and utilizes and identifies launch window blackout times to avoid close approaches of launch trajectories from anywhere within an area with remaining objects in space as noted in a space object catalog.

Nonlinear Variable Lag Smoother

US Patent Issued Inventors
8,433,544 4.30.2013 James Wright and James Woodburn

An extended Kalman filter (EKF) is combined with a fixed epoch smoother (FES) to produce a new variable lag smoother (VLS). The fixed epoch lags EKF measurement time-tags with variable time lag. The combination of EKF and FES is referred to herein as a variable lag smoother (VLS).

System and Method for Assessing the Risk of Conjunction of a Rocket Body with Orbiting and Non-Orbiting Platforms

US Patent Issued Inventor
8,275,498 9.25.2012 Salvatore Alfano

This patent explains how to create and depict a vulnerability volume (a.k.a. kill basket) for a ground-, sea- or air-launched interceptor.

System and Method for Aircraft Mission Modeling

US Patent Issued Inventor
8,221,122 7.17.2012 Tom Neely

This patent covers technology used in AGI’s Aviator product.

Addressing Nonlinear Relative Motion for Collision Probability Using Parellelepipeds

US Patent Issued Inventor
8,041,509 10.18.2011 Salvatore Alfano

This patent addresses a method for collision probability analysis using parallelepipeds.

Method for Visualizing Data Clouds Using Color and Opacity Blending

US Patent Issued Inventors
7,928,9807 4.19.2011 Paul Graziani, Edward Mackey, and David Massa

This patent covers a method developed for AGI software to analyze and visualize large data sets.

Visualization of Field-of-View Constraints

US Patent Issued Inventor
7,609,907 10.27.2009 Dr. Sergei Tanygin

This patent covers a method used in AGI software to compute one or more directional contours or horizons that encompass regions of space visible to the sensor. AGI's core COTS software offering, STK, uses this invention to determine and visualize complex visibility conditions that arise when sensor field-of-view is further limited by additional constraints, for example, the ground sample distance. With this method, STK leverages its comprehensive system of visibility computations to produce accurate and informative visualizations of complex time-dynamic geometries on 2D maps and in 3D scenes.

Method for Refining State Estimates of a Global Positioning System (GPS) Receiver Based Upon Sequential GPS Carrier Phase Measurements

US Patent Issued Inventors
7,423,583 09.09.2008 Jim Wright, William Chuba, and Dick Hujsak

Sequential GPS Doppler carrier phase count measurements are used for precision sequential determination of position and velocity of a GPS receiver, such as for orbit determination and geolocation, with minimum throughput time. Real-time orbit determination and geolocation performance is enabled with an optimal sequential filter, and near-real-time performance is enabled with an optimal fixed-lag smoother. Many problems associated with prior art orbit determination are eliminated by addressing the "cycle slip" problem, the unknown initial range problem with RANGE.sup.CP measurement representations, the problem of serial correlation in the measurements due to reprocessing of overlapping thermal noise. Also, the present invention significantly attenuates the carrier signal phase variation due to rotation of receiver antenna relative to transmitter antenna because the sequential phase count time intervals are sufficiently short.

A System and Method for Visualization and Attitude/Position-Dependent Data

US Patent Issued Inventors
7,224,311 05.29.2007 Dr. Haroon Rashid and Dr. Sergei Tanygin

An attitude sphere is defined around an object of interest located at the center. Grid points are defined on the surface of the attitude sphere to represent directions. An attitude dependent FOM result is mapped onto the sphere, which is colorcoded on the associated point to visualize attitude dependency. When used to analyze signals arriving at a receiver, the method accounts for motion of the receiver, the transmitter, and the signal sources.

GPS Carrier Phase Measurement Representation and Method of Use

US Patent Issued Inventors
7,050,002 05.23.2006 Jim Wright, William Chuba, Dick Hujsak

This patent covers technology used in AGI's Orbit Determination Tool Kit, and discusses how real-time orbit determination and geolocation performance is enabled with an optimal sequential filter and how near-real-time performance is supported by an optimal fixed-lag smoother. Many problems associated with prior art orbit determination are eliminated by addressing the "cycle slip" problem, the unknown initial range problem with RANGE.sup.CP measurement representations, the problem of serial correlation in the measurements due to reprocessing of overlapping thermal noise. Also, the present invention significantly attenuates the carrier signal phase variation due to rotation of receiver antenna relative to transmitter antenna because the sequential phase count time intervals are sufficiently short

Method and Apparatus for Sequentially Profiling and Solving Problems in Space Mission Analysis

US Patent Issued Inventors
6,937,968 08.30.2005 John Carrico and Frank Stoner

This patent covers technology used in AGI's STK/Astrogator module. It provides a system and method for orbital planning that allows iterative calculations of orbital parameters to be accomplished in an automated way with one parameter solutionserving as input to the next parameter's calculation. A software program employs a graphical user interface (GUI) to allow a space mission analyst to set up a series of sub-problems of any desired level of complexity. The program then implements the series automatically and sequentially, incorporating the solution to one sub-problem into the input to the next.

Method and Apparatus for Creating Elements and Systems for Description of Position and Motion of Bodies in Three-Dimensional Space to Support Orbital Maneuver Analysis

US Patent Issued Inventor
6,859,769 02.22.2005 Dr. Sergei Tanygin

This patent covers technology used in AGI's Vector Geometry Tool. It provides a graphical user interface and software architecture that empowers users to create new vectors, axes, points, coordinate systems, and other elements. The explicit means of creating coordinate systems and primitives are carried out via user input, imported data from files, or any other means of supplying numerical data to computer programs.

Method and Apparatus for Determining Obscuration of Sensors that are Mounted on a Spacecraft

US Patent Issued Inventor
6,850,875 02.01.2005 Deron Ohlarik

This patent is based on an innovation that covers technology used in AGI's STK/Advanced Visualization Option module.The field of view of a sensor mounted on a satellite (or other spacecraft) is obscured by various objects, such as celestial bodies and the satellite's own solar panels. A method is disclosed for visualizing and quantifying, with respect to time, variations in the portions of the sensor's field of view that are obscured. The graphical output of a satellite systems analysis program, which features high-resolution, three-dimensional, animated images of spacecraft, celestial bodies and other objects in the space environment, is utilized. The graphical output is simplified to only a few colors to differentiate only background and irrelevant objects from relevant objects. Differentiation is also made, using different colors, in representation of those portions of the field of view that overlap relevant (obscuring) objects from the remainder of the field of view which is unobscured. By counting pixels of the respective colors, frame-by-frame during animation, the percentage of obscuration over time is quantified.

Method and Apparatus for Orbit Determination

US Patent Issued Inventor
6,708,116 03.16.2004 Jim Wright

Technology covered by the patent is used in AGI's Orbit Determination Tool Kit. A method and apparatus for estimating the orbits of spacecraft or other objects relative to primary celestial bodies, given applicable measurements. The present invention uses the variation of parameters in universal variables for spacecraft trajectory propagation during operation of its optimal sequential orbit estimation. This method provides a universal capability for all three conics: elliptic, parabolic, and hyperbolic, forward-time and backward-time numerical integration for filtering and smoothing, respectively. A method for determining local and global estimates of atmospheric density is also provided. A method for realistic orbit simulation provides a means for validating an orbit estimate.

Method and Apparatus for Modelling Transmitter Bandwidth for Telecommunications Analysis

US Patent Issued Inventor
6,473,597 10.29.2002 Tom Johnson

Technology covered by the patent is used in AGI's Orbit Determination Tool Kit. A method and apparatus for estimating the orbits of spacecraft or other objects relative to primary celestial bodies, given applicable measurements. The present invention uses the variation of parameters in universal variables for spacecraft trajectory propagation during operation of its optimal sequential orbit estimation. This method provides a universal capability for all three conics: elliptic, parabolic, and hyperbolic, forward-time and backward-time numerical integration for filtering and smoothing, respectively. A method for determining local and global estimates of atmospheric density is also provided. A method for realistic orbit simulation provides a means for validating an orbit estimate.

Method and Apparatus for Determining Optimal Paths Among Objects of a Communications Network

US Patent Issued Inventor
6,195,553 02.27.2001 Dave Holland

This invention involves evaluating available links and identifying the optimal path between the starting point and the desired end point in a communications system when the availability of the links is in a constant state of change. The invention has been incorporated into functionality provided to Iridium in the STK/Chains module.

Method and Apparatus for Alerting a User Regarding the Position of a Satellite

US Patent Issued Inventor
6,160,509 12.12.2000 Paul Graziani

The patent is based on an invention involving a method for determining the position of a satellite overhead using a portable device such as a wristwatch or handheld computer. The required data can be downloaded from a larger unit, such as a PC, for later use in the field.

Method and Apparatus for Calculating Access Between Satellite Constellations and Ground Targets

US Patent Issued Inventor
6,144,334 11.07.2000 Dr. Jim Woodburn

For a given constellation of satellites, each with a number of sensors, this invention is a method for determining the access times between each sensor and multiple ground targets of varying shapes and sizes. This process has been integrated into many key visibility analysis methods within the STK software suite.

Method and Apparatus for Determining Close Approaches for Earth-Fixed Launch Trajectories

US Patent Issued Inventor
6,102,334 08.15.2000 Dr. Jim Woodburn

This invention involves a method for minimizing close approaches between a launch vehicle and other objects in space during the launch and early deployment phase of the vehicle. This AGI invention has been incorporated into the close approach analysis feature within STK/Conjunction Analysis Tools (STK/CAT).

Method and Apparatus for Modeling Receiver Bandwidth for Telecommunications Analysis

US Patent Issued Inventor
6,021,268 02.01.2000 Tom Johnson

Process for modeling a telecommunications link by automatically scaling the bandwidth of the receiver to take account of the varying data rates and modulation types of one or more transmitters in the system. This is essentially the receiver "autoscaling" feature of the STK/Comm module.

Method and Apparatus for Determination of Spacecraft Drag

US Patent Issued Inventor
6,011,913 01.04.2000 Jimmy Tucholski

Process for modeling atmospheric and other types of drag that can affect a satellite over a given interval, such as an orbit period. This can be used to predict orbit decay and calculate fuel requirements for orbit maintenance and station keeping.

Method and Apparatus for Determining Exposure of Spacecraft-Mounted Solar Panels to Sun

US Patent Issued Inventor
5,864,489 01.04.2000 Jimmy Tucholski

Process for modeling the exposure of solar power panels on a satellite or other spacecraft to the Sun over a period of time. This can be used to determine the availability of electrical power for operations to be performed by the spacecraft and on-board equipment.