LaserFeatureExtractorCombined
[LaserFeatureExtractor drivers, C++, Linux]

An ACFR implementation of a laser feature extractor. More...

An ACFR implementation of a laser feature extractor.

Configuration

The configuration documentation is split into sections for each feature type

General

• The uncertainty of point features
  • PointTargetRangeSd (float) [m]
    • Default: 0.2
  • PointTargetBearingSd (float) [deg]
    • Default: 5.0
      • Note these values need to take into account:
        • Inherent sensor uncertainty
        • Sensor offset uncertainty
        • Timing uncertainty

Reflectors

• ExtractReflectors (bool)
  • Default: true

• Reflectors.MaxDeltaRangeNearReflector (float) [m]
  • Don't extract a feature if there's a jump in the ranges > this threshold near the reflector. This rejects spurious reflectors that are partially-obscured behind a foreground obstacle. It also reduces the angles about which a reflector on a corner can be extracted.
  • Default: 0.5

• Reflectors.MaxDeltaRangeWithinReflector (float) [m]
  • A reflector that includes a jump in range > this threshold will be ignored. Default: 0.3

• Reflectors.MinBrightness (int)
  • minimum intensity value to be considered a feature
  • Default: 1

• Reflectors.PFalsePositive (float)
  • porbability of a false positive
  • Default: 0.1

• Reflectors.PTruePositive (float)
  • probability of a true positive
  • Default: 0.6

Foreground Points

• ExtractForegroundPoints (bool)
  • Default: 0

• FGPoints.MinForegroundWidth (float) [m]
  • minimum width of poles/trees
  • Default: 0.01

• FGPoints.MaxForegroundWidth (float) [m]
  • maximum width of poles and trees
  • Default: 0.5

• FGPoints.MinForegroundBackgroundSeparation (float) [m]
  • The pole must be at least this far from the background or other clutter
  • Default: 2.0

• FGPoints.ClearForegroundBackgroundSeparation (float) [m]
  • pTruePositive/pFalsePositive gets scaled according to the distance from clutter. ClearForegroundBackgroundSeparation is the distance at which scaling no longer happens.
  • Default: 4.0

• FGPoints.ReliableScannerRange (float) [m]
  • At short ranges you get fewer false positives
  • Default: 5.0

• FGPoints.PFalsePositive (double)
  • Probability of detecting a false-positive foreground point
  • Default: 0.4

• FGPoints.PTruePositive (double)
  • Probability of detecting a true-positive foreground point
  • Default: 0.5

Lines

• ExtractLines (bool)
  • Default: 1

• Lines.MaxDeltaRangeInCluster (float) [m]
  • Points are first clustered before fitting lines.
  • A change in range greater than this breaks a cluster.
  • Default: 0.5

• Lines.MaxDeltaInLine (float) [m]
  • For a line to be fit, the orthogonal distance of each point from the line must be less than this.
  • Default: 0.1

• Lines.MinPointsInLine (int)
  • Self-explanatory
  • Default: 6

• Lines.MinLineLengthForLineFeature (float) [m]
  • Self-explanatory
  • Default: 1.0

• Lines.MinLineLengthForVisibleEndpoints (float) [m]
  • Self-explanatory
  • Default: 1.0

• Lines.PFalsePositive (double)
  • Probability of detecting a false-positive line
  • Default: 0.4

• Lines.PTruePositive (double)
  • Probability of detecting a line when it's really there
  • Default: 0.6

Corners

• ExtractCorners (bool)
  • Default: 1
• PFalsePositive (double)
  • Probability of detecting a false-positive corner
  • Default: 0.2
• PTruePositive (double)
  • Probability of detecting a true-positive corner
  • Default: 0.6

• The corner extractor looks for intersecting lines. It relies on the line extractor, and is therefore affected by the line extractor's configuration (with the exception of the MinLineLength parameter: the corner detector will look for the intersection of smaller lines than the line detector is configured for).

Doors

• ExtractDoors (bool)
  • Default: 0
• Doors.MinDoorWidth (double)
  • Default: 0.9
• Doors.MaxDoorWidth (double)
  • Default: 1.2
• Doors.MinDeltaRangeThruDoor (double)
  • Default: 2.0
• Doors.RangeSd (double)
  • Default: 0.3
• Doors.BearingSd (double)
  • Default: 5.0
• Doors.MinReturnsThruDoor (int)
  • Default: 3
• Doors.MinReturnsBesideDoor (int)
  • Default: 2
• Doors.MaxDeltaRangeWallBesideDoor (double)
  • Default: 0.3

Authors

Alex Brooks