uwcse.location.core
Class SmoothCentroidTracker

java.lang.Object
  |
  +--uwcse.location.core.Tracker
        |
        +--uwcse.location.core.MobileTracker
              |
              +--uwcse.location.core.CentroidTracker
                    |
                    +--uwcse.location.core.SmoothCentroidTracker

public class SmoothCentroidTracker

extends CentroidTracker

A class containing functionality to track a physical object or set of grouped physical objects where the tracked object is placed at the centroid of the position's of the last n sensors making measurements, smoothed by the history of previous centroids. The history size is the number of past estimated positions (including the current) that are averaged to estimate the tracked object's current position. A history size of 1 results in no smoothing.

Version:

$Revision: 1.2 $

Author:

Jeffrey Hightower

Field Summary
protected  State[]	m_history
protected  int	m_historyIndex

 

Fields inherited from class uwcse.location.core.CentroidTracker

m_index, m_useWeighting, m_values, m_window

 

Fields inherited from class uwcse.location.core.MobileTracker

m_motionModel

 

Fields inherited from class uwcse.location.core.Tracker

m_elapsedTime, m_lastMeasurement, m_lastUpdateTime, m_trueStateMeasurement, m_worldMap

 

Constructor Summary

SmoothCentroidTracker(SmoothCentroidTracker tracker)           Create a point object tracker as a copy of this one.

SmoothCentroidTracker(WorldMap map, MotionModel motion, boolean useWeighting)           Create a centroid tracker with a window size of 3 and a smoothing history size of 2.

SmoothCentroidTracker(WorldMap map, MotionModel motion, boolean useWeighting, int windowSize, int historySize)           Create a centroid tracker with the given centroid window size, weighting, and smoothing history.

 

Method Summary
Object	clone()           Create a point object tracker as a copy of the given one.
LocationReport	createLocationReport()           Compute a state location report for the object being tracked.
int	getHistorySize()           Get the history size, that is, the number of past estimated positions (including the current) that are averaged to estimate the tracked object's current position.
void	initLocation(LocationReport report)           Initialize the tracker to the given location.
void	merge(Tracker tracker)           Incorporate information contained in given tracker into this tracker.
String	toString()           Return a string representation of this particle filter tracker.
void	update(Measurement meas, LocationSensor sensor, LocationReport sensorLocation)           Update to reflect the given measurement taken by the given location sensor.

 

Methods inherited from class uwcse.location.core.CentroidTracker

getWindowSize

 

Methods inherited from class uwcse.location.core.MobileTracker

getMotionModel, setMotionModel

 

Methods inherited from class uwcse.location.core.Tracker

getLastMeasurement, getRMSError, getTimestamp, getTrueStateMeasurement, getWorldMap, setTrueStateMeasurement

 

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

 

Field Detail

m_history

protected State[] m_history

m_historyIndex

protected int m_historyIndex

SmoothCentroidTracker

public SmoothCentroidTracker(WorldMap map,
                             MotionModel motion,
                             boolean useWeighting)

Create a centroid tracker with a window size of 3 and a smoothing history size of 2.

SmoothCentroidTracker

public SmoothCentroidTracker(WorldMap map,
                             MotionModel motion,
                             boolean useWeighting,
                             int windowSize,
                             int historySize)

Create a centroid tracker with the given centroid window size, weighting, and smoothing history. The smoothing history size must be greater than 0 or an IllegalArgumentException will be thrown.

SmoothCentroidTracker

public SmoothCentroidTracker(SmoothCentroidTracker tracker)

Create a point object tracker as a copy of this one.

clone

public Object clone()

Create a point object tracker as a copy of the given one.

Overrides:

clone in class CentroidTracker

update

public void update(Measurement meas,
                   LocationSensor sensor,
                   LocationReport sensorLocation)

Update to reflect the given measurement taken by the given location sensor. The tracked object's new position is window size measurements plus this one whose sensor positions are averaged.

Overrides:

update in class CentroidTracker

getHistorySize

public int getHistorySize()

Get the history size, that is, the number of past estimated positions (including the current) that are averaged to estimate the tracked object's current position.

createLocationReport

public LocationReport createLocationReport()

Compute a state location report for the object being tracked.

Overrides:

createLocationReport in class CentroidTracker

toString

public String toString()

Return a string representation of this particle filter tracker.

Overrides:

toString in class CentroidTracker

initLocation

public void initLocation(LocationReport report)

Initialize the tracker to the given location. This implementation fills the window with the given report's most likely state.

Overrides:

initLocation in class CentroidTracker

merge

public void merge(Tracker tracker)

Incorporate information contained in given tracker into this tracker.

Overrides:

merge in class CentroidTracker