lejos.localization
Class Particle

java.lang.Object
  lejos.localization.Particle

public class Particle
extends Object

Represents a particle for the particle filtering algorithm. The state of the particle is the pose, which represents a possible pose of the robot. The weight for a particle is set by taking a set of theoretical range readings using a map of the environment, and comparing these ranges with those taken by the robot. The weight represents the relative probability that the robot has this pose. Weights are from 0 to 1.

Author:

Lawrie Griffiths

WARNING: THIS CLASS IS SHARED BETWEEN THE classes AND pccomms PROJECTS. DO NOT EDIT THE VERSION IN pccomms AS IT WILL BE OVERWRITTEN WHEN THE PROJECT IS BUILT.

Field Summary

static Random

rand

Constructor Summary

Particle(Pose pose)
Create a particle with a specific pose

Method Summary

void	applyMove(Move move) Apply the robot's move to the particle with a bit of random noise
void	calculateWeight(RangeReadings rr, Map map) Calculate the weight for this particle by comparing its readings with the robot's readings
Pose	getPose() Return the pose of this particle
float	getReading(int i) Get a specific reading
float	getWeight() Return the weight of this particle
void	setWeight(float weight) Set the weight for this particle
void	takeReadings(Map map) Calculate the theoretical readings

Methods inherited from class java.lang.Object

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

Field Detail

rand

public static Random rand

Constructor Detail

Particle

public Particle(Pose pose)

Create a particle with a specific pose

Parameters:

pose - the pose

Method Detail

setWeight

public void setWeight(float weight)

Set the weight for this particle

Parameters:

weight - the weight of this particle

getWeight

public float getWeight()

Return the weight of this particle

Returns:

the weight

getPose

public Pose getPose()

Return the pose of this particle

Returns:

the pose

calculateWeight

public void calculateWeight(RangeReadings rr,
                            Map map)

Calculate the weight for this particle by comparing its readings with the robot's readings

Parameters:

rr - Robot readings

takeReadings

public void takeReadings(Map map)

Calculate the theoretical readings

Parameters:

map - the map of the environment

getReading

public float getReading(int i)

Get a specific reading

Parameters:

i - the index of the reading

Returns:

the reading

applyMove

public void applyMove(Move move)

Apply the robot's move to the particle with a bit of random noise

Parameters:

move - the robot's move