Module: star_tracker

Sensor model to simulate a Star Tracker.

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

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class StarTracker : public SysModel

#include <star_tracker.h>

star tracker class

Public Functions

StarTracker()

~StarTracker()

bool LinkMessages()

link messages

void UpdateState(uint64_t CurrentSimNanos)

update module states

void SelfInit()

self initialization

void CrossInit()

cross initialization

void readInputMessages()

read input messages

void writeOutputMessages(uint64_t Clock)

write output messages

void computeSensorErrors()

compute sensor errors

void applySensorErrors()

apply sensor errors

void computeTrueOutput()

compute true output values

void computeQuaternion(double *sigma, STSensorIntMsg *sensorValue)

compute quaternion from MRPs

Parameters

• sigma:

• sensorValues:

Public Members

uint64_t sensorTimeTag

[ns] Current time tag for sensor out

std::string inputStateMessage

[-] String for the input state message

std::string outputStateMessage

[-] String for the output state message

bool messagesLinked

[-] Indicator for whether inputs bound

Eigen::Matrix3d PMatrix

[-] Cholesky-decomposition or matrix square root of the covariance matrix to apply errors with

Eigen::Vector3d walkBounds

[-] “3-sigma” errors to permit for states

Eigen::Vector3d navErrors

[-] Current navigation errors applied to truth

uint64_t OutputBufferCount

[-] Count on the number of output message buffers

double dcm_CB[3][3]

[-] Transformation matrix from body to case

STSensorIntMsg trueValues

[-] total measurement without perturbations

STSensorIntMsg sensedValues

[-] total measurement including perturbations

double mrpErrors[3]

[-] Errors to be applied to the input MRP set indicating whether

SCPlusStatesSimMsg scState

[-] Module variable where the input State Data message is stored

BSKLogger bskLogger

BSK Logging

Private Members

Eigen::Matrix3d AMatrix

[-] AMatrix that we use for error propagation

int64_t inputStateID

[-] Connection to input state message

int64_t outputStateID

[-] Connection to outgoing state message

GaussMarkov errorModel

[-] Gauss-markov error states