lejos.robotics.localization
Class MCLParticle

java.lang.Object
  extended by lejos.robotics.localization.MCLParticle

public class MCLParticle
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

Constructor Summary
MCLParticle(Pose pose)
          Create a particle with a specific pose
 
Method Summary
 void applyMove(Move move, float distanceNoiseFactor, float angleNoiseFactor)
          Apply the robot's move to the particle with a bit of random noise.
 void calculateWeight(RangeReadings rr, RangeMap map, float divisor)
          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, RangeReadings rr, RangeMap map)
          Get a specific reading
 RangeReadings getReadings(RangeReadings rr, RangeMap map)
           
 float getWeight()
          Return the weight of this particle
static void setDebug(boolean yes)
           
 void setWeight(float weight)
          Set the weight for this particle
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

MCLParticle

public MCLParticle(Pose pose)
Create a particle with a specific pose

Parameters:
pose - the pose
Method Detail

setDebug

public static void setDebug(boolean yes)

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,
                            RangeMap map,
                            float divisor)
Calculate the weight for this particle by comparing its readings with the robot's readings

Parameters:
rr - Robot readings

getReading

public float getReading(int i,
                        RangeReadings rr,
                        RangeMap map)
Get a specific reading

Parameters:
i - the index of the reading
Returns:
the reading

getReadings

public RangeReadings getReadings(RangeReadings rr,
                                 RangeMap map)

applyMove

public void applyMove(Move move,
                      float distanceNoiseFactor,
                      float angleNoiseFactor)
Apply the robot's move to the particle with a bit of random noise. Only works for rotate or travel movements.

Parameters:
move - the robot's move