nHingedRigidBodyStateEffector

Executive Summary

This class is an instantiation of the stateEffector class and is a N-hinged rigid body effector. This effector is a rigid body attached to the hub through a torsional spring and damper that approximates a flexible appendage. See Allard, Schaub, and Piggott paper: General Hinged Solar Panel Dynamics Approximating First-Order Spacecraft Flexing for a detailed description of this model. A hinged rigid body has 2 states: theta and thetaDot

The module PDF Description contains further information on this module’s function, how to run it, as well as testing.

Message Connection Descriptions

This state effector has no input or output messages.

Class NHingedRigidBodyStateEffector

class NHingedRigidBodyStateEffector : public StateEffector, public SysModel

NHingedRigidBodyStateEffector class.

Public Functions

inline void addHingedPanel(HingedPanel NewPanel)

class method

NHingedRigidBodyStateEffector()

— Contructor

This is the constructor, setting variables to default values

~NHingedRigidBodyStateEffector()

— Destructor

This is the destructor, nothing to report here

double HeaviFunc(double cond)

— Heaviside function used for matrix contributions

• Method for defining the Heaviside function for the EOMs */

void WriteOutputMessages(uint64_t CurrentClock)

This method takes the computed theta states and outputs them to the messaging system.

Parameters:

CurrentClock – The current simulation time (used for time stamping)

Returns:

void

void updateState(uint64_t currentSimNanos)

This method is used so that the simulation will ask HRB to update messages.

Parameters:

currentSimNanos – The current simulation time in nanoseconds

Returns:

void

void registerStates(DynParamManager &statesIn)

— Method for registering the HRB states

This method allows the HRB state effector to register its states: theta and thetaDot with the dyn param manager

void linkInStates(DynParamManager &states)

— Method for getting access to other states

This method allows the HRB state effector to have access to the hub states and gravity

void updateEffectorMassProps(double integTime)

— Method for stateEffector to give mass contributions

This method allows the HRB state effector to provide its contributions to the mass props and mass prop rates of the spacecraft

void updateContributions(double integTime, BackSubMatrices &backSubContr, Eigen::Vector3d sigma_BN, Eigen::Vector3d omega_BN_B, Eigen::Vector3d g_N)

— Back-sub contributions

This method allows the HRB state effector to give its contributions to the matrices needed for the back-sub method

void updateEnergyMomContributions(double integTime, Eigen::Vector3d &rotAngMomPntCContr_B, double &rotEnergyContr, Eigen::Vector3d omega_BN_B)

— Energy and momentum calculations

This method is for calculating the contributions of the HRB state effector to the energy and momentum of the s/c

void computeDerivatives(double integTime, Eigen::Vector3d rDDot_BN_N, Eigen::Vector3d omegaDot_BN_B, Eigen::Vector3d sigma_BN)

— Method for each stateEffector to calculate derivatives

This method is used to find the derivatives for the HRB stateEffector: thetaDDot and the kinematic derivative

void readInputMessages()

— method to read input messages

This method reads necessary input messages

Returns:

void

Public Members

std::string nameOfThetaState

— Identifier for the theta state data container

std::string nameOfThetaDotState

— Identifier for the thetaDot state data container

Eigen::Vector3d r_HB_B

[m] vector pointing from body frame origin to the first Hinge location

Eigen::Matrix3d rTilde_HB_B

— Tilde matrix of rHB_B

Eigen::Matrix3d dcm_HB

— DCM from body frame to hinge frame

BSKLogger bskLogger

— BSK Logging