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FormationFlying

Directory List

Analysis, Collision, Control, Coord, DataStructures, Dynamics, EccDynamics, Guidance, IntegratedSim, LP, Transformation, Utility, Visual, Demos/Collision, Demos/Control, Demos/Coord, Demos/Dynamics, Demos/Eccentric, Demos/Guidance, Demos/LP,

Functions and Demos

Analysis

AnalyzeVariableTimeDV - Plot the behavior of the first and third delta-v in a 3-burn sequence

CheckDeltaVs - Plot the trajectory that will result from a planned maneuver.

CompareHills - Compare closed form Hills equations with other methods of propagation.

DFFSim - Simulation routine for testing DFF guidance and control laws.

DeltaVAnalysis - Compute the total delta-v assoc. w/ several types of reconfigurations.

DriftRateSigma - Find the standard deviation of along-track drift per orbit due to rel nav errors.

FFEccFrameCompare - Compare two methods of computing the relative motion in an eccentric orbit.

FFMaintenancePlotter - Plot the results from "FFMaintenanceSim".

FFMaintenanceSim - Formation flying maintenance simulation.

FFMaintenanceTests - Returns data associated with various test runs for "FFMaintenanceSim".

FindDriftTerm - Find the "deadband over drift rate sigma" term that results in the specified

LPvsCF - Compare the delta-v and trajectory for two methods of relative orbit control.

RelativeVelocityError - Compute max. navigation error that maintains the specified performance.

TestFFEccLinOrb - Test the FFEccLinOrb function. An initial reference state in the ECI frame

TestLPCircular - Test the LPEccentric function. Provide the reference orbital elements, an

TestLPEccentric - Test the LPEccentric function.

TestLPEccentricGVE - Test the LPEccentricGVE function.


Collision

CoarseProb - Coarse probability estimate consisting of the integral outbound of the

CollMonDemo - Collision monitoring demo: compare CollisionSurvey and coarse methods

CollProbSet - Calculates the probability of collision given two ellipsoid sets. For

CollProbVol - Calculates the probability of collision given two ellipsoids

CollisionInit - Sample data for collision algorithm initialization

CollisionMonAlg - Collision monitoring algorithm. Discretizes orbit according to input

CollisionMonitor - Runs the collision monitoring algorithm. Checks the ellipsoids for self

CollisionMonteCarlo - Perform a Monte-Carlo analysis of a relative orbit dynamics simulation

CollisionSurvey - Runs the collision monitoring algorithm for n spacecraft relative

ConjuntionPlane - Transformation matrix for relative conjunction geometry. The inertial

DistantPtToEll - Finds the distance (and the corresponding point) from a distant

EllipsePatch - Form:

EllipsePropCirc - Function finds the propagated state uncertainty ellipsoid

Ellipsoid - Calculates an ellipsoid given the ellipsoid matrix, semimajor axes, the unit

GenerateTimeVector - Generate a time vector evenly spaced over true anomaly

HillsDisturb - Disturbances in Hills frame. Includes uncertainty.

Laguerre - Finds the polynomial roots using Laguerre's method. There is a fix in

MinDEllipsoid - Computes the minimum distance between two ellipsoids

Plot3DEllipsoids - Plots ellipsoids given the ellipsoid centers and matrices

PredictCollision - Runs the collision monitoring algorithm. Propagates forward for a fixed time

RelativeDisturb - Relative disturbances for use with a relative state.

VerifyCollStruct - Ensure consistency in collision data structure fields.

ViewEllipsoid - Plots ellipsoids for Collision Monitoring given the ellipsoid centers and

WorstCasePerturbations - Differential accelerations for spacecraft in formation assuming the


Control

ImpulsiveLPManeuver - Computes the delta-v sequence for a relative orbit maneuver.

ImpulsiveManeuver - Computes a delta-v sequence for a relative orbit maneuver in a circular orbit

InPlane - Computes the delta-v's required for an in-plane maneuver.

IterativeImpulsiveManeuver - Computes the delta-v's required to implement a formation flying maneuver for

LinOrbLQG - Generate an LQG controller for linearized relative orbit dynamics.

Lyapunov - Compute a constant gain feedback controller for relative orbital motion.

OptimalInPlaneDeltaV - Computes the delta-v's and half-orbit delays for an in-plane maneuver.

OutOfPlane - Computes the delta-v's required for an out-of-plane maneuver.


Coord

AddGoals - Add one set of geometric goals to the other.

AlignThruster - Computes the desired Hills-to-Body frame quaternion for a thruster firing.

CirclePhase - Compute the desired phase on the circle from the desired phase on the ellipse.

EllipsePhase - Compute the desired phase on the ellipse from the desired phase on the circle.

GetHillsMats - This function takes the position and velocity of a satellite in the ECI

GetLVLHMats - This function takes the position and velocity of a satellite in the ECI

InitializeFormation - Generate the initial orbital elements for a cluster of spacecraft given

IsCircGeom - Check whether the supplied data structure is for circular geometry or not.

IsEccGeom - Check whether the supplied data structure is for eccentric geometry or not.

LFState - Computes the position and velocity of a satellite in the Hills frame for a

OrbElemDiff - Computes the differences between orbital element vectors.

PCState - Computes the position and velocity of a satellite on the local ellipse

ProjCirc - Calculates orbital elements for projected circular formation.

ProjLine - Calculates orbital elements for an in-line formation.

QFrenet - Generate the quaternion that transforms from the ECI to the Frenet frame.

QHillsToBody - Compute the Hills-to-Body quaternion given the ECI position and velocity, and

RotateState - Rotate a geometric state to the circular phase angle phi.

ScaleState - Scale a relative state represented by a geometric goal set. This

SubGoals - Subtract one set of geometric goals from the other.

TeamGoals2Geom - Extract the geometry data from the team goals data structure

ThrusterAlignment - Computes body vectors to align with velocity and nadir for a thruster firing.


DataStructures

BurnData_Structure - Initialize a burn data structure.

Command_Structure - Command data structure for external commands supplied to DFF system.

Constraints_Structure - Initialize a constraints data structure.

CostEstimate_Structure - Initialize a cost estimate data structure.

DeltaVCommand_Structure - Initialize a delta-v command data structure.

EccGeometry_Structure - Initialize an eccentric geometry data structure.

EccTeamGoals_Structure - Initialize a team goals data structure (for eccentric geometries)

Geometry_Structure - Initialize a geometry data structure.

ISLMessage_Structure - The ISL message data structure format.

Maneuver_Structure - Initialize a maneuver data structure.

Orientation_Structure - Initialize an orientation command data structure.

PlanningParameters_Structure - Initialize a planning parameters data structure.

State_Structure - Initialize a state data structure.

TeamGoals_Structure - Initialize a team goals data structure.

Team_Structure - Initialize a team data structure.

Window_Structure - Initialize a window data structure.


Dynamics

DiscreteHills - Computes the state trajectory (xS) of a satellite given the initial state (x0)

FFIntegrate - Integrate two neighboring orbits, with applied relative accelerations

GVEDynamics - Compute continuous-time relative dynamics for Gauss' variational equations

HillsEqns - Closed form solution of relative orbital motion using Hills equations.

RelativeOrbitRHS - Continuous-time linear model of Hills equations in Hills frame.


EccDynamics

DiscreteGVE - Computes the relative state trajectory in an eccentric reference orbit.

FFEccDH - Compute integration constant dH for homogeneous solution to LTV diff eqs

FFEccDMatPeriodic - Given an initial Hills state (xH0) at a particular true anomaly (nu0)

FFEccDiscreteHills - Computes the relative state trajectory in an eccentric reference orbit.

FFEccGoals - Compute integration constants and initial state given the geometric goals.

FFEccH - Compute the H term for the homogeneous solution to LTV diff eqs

FFEccIntConst - Compute integration constants for homogeneous solution to LTV diff eqs

FFEccLawdensEqns - Compute Hills frame state given initial state, true anomaly, and eccentricity

FFEccLinOrb - Compute the continous A,B matrices for linearized relative motion in an

FFEccProp - Compute Hills frame state at nu given integ. constants and eccentricity.

FFEccRMat - Compute the state-transition matrix, R, given the eccentricity and true anomaly.

FFEccXExt - Compute extreme x-values and associated true anomalies for given relative motion.

FFEccYExt - Compute extreme y-values and associated true anomalies for given relative motion.

FFEccZExt - Compute extreme z-values and associated true anomalies for given relative motion.


Guidance

AutoFormGeometry - Define new geometric goals for a single satellite, such that any semi-major

CostMatrixRows - Given the team goals, determines the starting row (a) and ending row (b)

DistributeClusterGoals - Given a set of geometric goals for the cluster, with corresponding target

EstimateCost - Estimate the (weighted) cost to achieve all specified unique target states.

FFEccEstimateCost - Estimate the weighted cost to achieve all specified unique target states

FFEccGenerateTeamGoals - Generate a Team Goals data structure given the formation type and size.

FFEccHexahedronGeometry - Compute the geometric goals for a formation that achieves a hexahedron

FFEccTetrahedronGeometry - Compute the geometric goals for a formation that achieves a tetrahedron shape

FindMinSet - Find the order of columns in a square matrix which minimizes

GenerateTeamGoals - Generate a Team Goals data structure given the formation type and size.

InitializeCostMatrix - Given the team goals, initialize the cost matrix "f" with the right size.

IsDuplicateState - Determine whether two geometric goal sets are duplicates or not.

NearestOffset - Determine the nearest along-track offset for a trajectory that is safe.

OptimalAssignment - Compute the optimal configuration for a group of objects.

PCGoals - Generate the geometric goals for a cluster in a projected circular formation.

PopulateCostMatrix - Fill in a single column of the cost matrix.

PrivilegedAssignment - Assign target states to satellites using the priveleged assignment method.

RestrictIDSet - Given an initial set of relative spacecraft IDs, examine the constraints

SetupAssignmentProblem - Set up the parameters for the assignment problem given the team goals struct.

SortTeamGoals - Sort the team goals with fixed states listed before variable states.


IntegratedSim

DFFAttitudeTarget - Generate a reference quaternion for a variety of targets. There

DFFControl - The executive function that initializes and runs the DFF software modules.

DFFRHS - Right-hand-side of the spacecraft dynamic equations for the DFF system.

DFFSimGUI - Computes the time left to go in the simulation, the predicted finish

DFFSimulation - Initialize and run a multiple spacecraft simulation with the DFF software.

RK4_DFFRHS - Fourth order Runge-Kutta for the DFF simulation right-hand-side.


LP

LPCircular - Computes the thrust trajectory to go from an initial state x0

LPCircularTimeWeight - Determine the target state on the desired trajectory that gives the minimum

LPEccentric - Computes the thrust trajectory to go from an initial state x0

LPEccentricGVE - Computes the thrust trajectory to go from an initial state x0 to a

LPEccentricTimeWeight - Determine the target state on the desired trajectory that gives the minimum


Transformation

AbsRelECI2Hills - This function takes the absolute position and velocity in the ECI frame along

DeltaAlfriend2El - Compute standard differential elements from Alfriend differential elements.

DeltaEl2Alfriend - Compute Alfriend differential elements from standard differential elements.

DeltaElem2Goals - Reconstructs the geometric goals from the element differences.

DeltaElem2Hills - Computes the Hills frame state from orbital element differences and

ECI2Hills - Compute the relative state in Hills frame given two ECI state vectors.

ECI2LVLH - This function takes two ECI state vectors, and returns the relative state in

ECI2MeanElements - Computes mean orbital elements from reference ECI position and velocity

FFEccDeltaElem2Goals - Convert element differences to eccentric geometric goals.

FFEccDeltaElem2Hills - Convert element differences to Hills frame coordinates in an eccentric orbit.

FFEccFrenet2Goals - Compute geometric goals given Frenet frame state and orbit info

FFEccGoals2Hills - Compute Hills frame state (time-domain) given geometric goals and orbit info

FFEccHills2DeltaElem - Compute element differences from Hills frame state and ref. elements

FFEccHills2Goals - Compute geometric goals given Hills frame state and orbit info

Frenet2Hills - Rotate the Frenet frame state to the Hills frame, where x is radial

GeometryCirc2Ecc - Convert a circular geometry structure to an eccentric geometry structure.

GeometryEcc2Circ - Convert an eccentric geometry structure to a circular geometry structure.

Goals2DeltaElem - Computes the desired orbital element differences, given the formation flying

Goals2Hills - Computes the desired relative position and velocity in Hills frame, given the

Hills2DeltaElem - Computes the orbital element differences from the Hills frame state and the

Hills2ECI - Given the reference state in ECI, converts a Hills frame state to ECI.

Hills2Frenet - Rotate the Hills frame state to the Frenet frame, where x is along-track

Hills2Goals - Reconstructs the geometric goals from the relative position and velocity in

Hills2LVLH - Converts a state vector from the Hills to the LVLH coordinate frame.

LVLH2ECI - Given the reference state in ECI, converts an LVLH frame state to ECI.

LVLH2Hills - Converts a state vector from the LVLH to the Hills coordinate frame.

Osc2Mean - Transforms osculating orbital elements to mean orbital elements.

TransformGeom2Hills - Transform geometric goals to hills-frame coordinates.


Utility

AccelVector2ManeuverStruct - Build a "maneuver" data structure from acceleration and time vectors.

ApplyDeltaV - Apply delta-v over a specified time interval with a simulation timestep

DataSize - Find the size in bytes of a piece of data.

FFEccTargetTrueAnom - Compute the future true anomaly (unwrapped) at the specified number of orbits

Hexahedron - Compute the 5 points of a regular tetrahedron, the surface area and volume.

JD2SS1970 - Converts a Julian Date to seconds since 00:00:00 GMT, Jan. 1, 1970.

ManeuverStruct2AccelVector - Compute a 3xN acceleration vector from a "maneuver" data structure.

MeanAnom2TrueLat - Convert mean anomaly to true latitude.

NOrbVector - Compute a vector of maneuver durations from time window data

NewtRaph2 - Finds the solution to f(x) = 0 given df(x)/dx when only one

Nu2TimeDomain - Convert a relative state from the nu-domain to the time-domain.

NuDot - Compute the time-derivative of the true anomaly.

RK4TI - Fourth order Runge-Kutta integration. RHS is time-independent (TI).

RVOrbGenDV - Generate an orbit by propagating Keplerian elements with impulsive delta-vs.

SS19702JD - Converts seconds since 00:00:00 GMT, Jan. 1, 1970 to a Julian date.

Tetrahedron - Compute the 4 points of a regular tetrahedron, the surface area and volume.

Time2NuDomain - Convert a relative state from the time-domain to the nu-domain.

TimeUntilTheta - Computes the time in seconds until the latitude "theta2" is reached from the


Visual

CostVis - Visualize the cost to achieve each target state on the trajectory.

DisplayPlugin - Display Plugin for the Formation Design GUI.

FFEccAnalyzeShape - Analyze the shape of a relative trajectory in an eccentric reference orbit.

FFEccShapes - Compute the shape of the relative motion in the orbital plane.

FormationDesign - Formation Design GUI.

GeometryPlugin - Geometry Plugin for the Formation Design GUI.

HillsFramePlot - Plot the trajectory in Hills frame and show the x-z, x-y projections.

IllustrateEccentricGeometry - Illustrate the geometric parameters that define a naturally repeating

OrbitDataPlugin - Orbit Data Plugin for the Formation Design GUI.

RelativeStatePlugin - Relative State Plugin for the Formation Design GUI.

SatellitePlugin - Satellite Plugin for the Formation Design GUI.

ShowTeams - Graphically show the hierarchy of teams.

TeamLevels - Assign a hierarchical level to each team in the array.

TeamPlugin - Team Plugin for the Formation Design GUI.

ViewFormation - View the 3-D trajectory of a formation in Hills frame.

ViewGeometry - View the geometry created by a formation of spacecraft

ViewHills - Given the reference orbital elements, a time span, and the spacecrafts'

ViewRelativeMotion - View the relative motion associated with a set of geometric goals and a

ViewRotatingHillsFrame - Animate a satellite's relative trajectory in the inertial frame.


Demos/Collision

AssignmentDemoMvr - Extension of AssignmentDemo to include collision monitoring.

CollDetectSim - Simulation for testing the collision monitoring algorithms. Computes the

CollisionCompareDemo - Collision monitoring demo: compare CollisionSurvey and coarse methods.

DistantPtToEllDemo - Copyright 2005 Princeton Satellite Systems, Inc. All rights reserved.

ReconfigCollisionDemo - Collision monitoring demo for highly eccentric reconfiguration to produce

SetProbabilityDemo - Set membership probability demo. Verify shape of function.


Demos/Control

EccentricControlAnalysis - Analyze the performance of relative orbit control in eccentric orbits

LQGEccDemo - Demonstrate LQG control of relative motion in an eccentric orbit

LQGOrbitControlDemo - Relative orbit control using LQG


Demos/Coord

RotateStateDemo - Demonstrate the RotateState function by rotating the specified

TransECIToHills - Two orbits are initialized with a small inclination difference. The orbits


Demos/Dynamics

FFHEOSolarDist - Simulate relative motion in a HEO orbit with solar pressure disturbance

PropagationExample - Compares the relative motion predicted by propagation of the discrete state-


Demos/Eccentric

EccTrajDemo - Demonstrate an example relative trajectory with an eccentric reference orbit

FFEccAssignmentDemo - Demonstrate the different solutions found by the optimal assignment

FFEccInitDemo - Demonstrate how relative motion changes when the same relative state is

FFEccPropDemo - Compare discrete propagation with continuous solution.

FFEccReconfigDemo - Compute several reconfiguation maneuvers of varying duration for an


Demos/Guidance

AssignmentDemo - Demonstrate the different solutions found by the optimal assignment

DFFReconDemo - Run a formation flying simulation with "DFFSim".


Demos/LP

LPConvergenceDemo - Examine the "convergence rate" for an impulsive LP solution

LPPerformanceDemo - Analyze the performance of the LPEccentric algorithm.


SVN Revision: 10873


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