laservisualbarcode
Drivers

Color laser/visual barcode detector. More...

Color laser/visual barcode detector.

Todo:
  This driver has not been tested with the v2.0 API

The laser visual barcode detector uses both searches for fiducials that are both retro-reflective and color-coded. Fiducials can be either planar or cylindical, as shown below. For planar targets, the range, bearing, orientation and identity will be determined; for cylindrical targets, the orientation will be undefined. The target size and shape can be set in the configuration file.

The laser visual barcode detector searches the laser range data to find retro-reflective targets, points the camera at each of these targets in turn, then uses color information to determine the presence and identity of fiducials. Thus, this detector makes use of three underlying devices: a laser range finder, a pan-tilt-zoom camera and a color blob detector. Note that the laser is used to determine the geometry of the fidicual (range, bearing and orientation), while the camera is used to determine its identity.

The range at which fiducials can be both detected and identified depends on a number of factors, including the size of the fiducial and the angular resolution of the laser. Generally speaking, however, this detector has better range than the laserbarcode detector, but produces fewer observations.

See also the laserbar and laserbarcode drivers.

A sample laser visual barcode.

Compile-time dependencies

- none

Provides

- This driver provides detected target information through a fiducial device.

Requires

- laser
- ptz
- blobfinder

Configuration requests

- PLAYER_FIDUCIAL_REQ_GET_GEOM

Configuration file options

- max_ptz_attention (float)
  - Default: 2.0
  - ??
- retire_time (float)
  - Default: 1.0
  - ??
- max_dist (float) (should be a length?)
  - Default: 0.2
  - ??
- bit_count (integer)
  - Default: 3
  - Number of bits in visual barcode
- bit_width (length)
  - Default: 0.08 m
  - Width of each bit in visual barcode
- bit_height (length)
  - Default: 0.02 m
  - Height of each bit in visual barcode

Example

    driver
    (
      name "laservisualbarcode"
      requires ["laser:0" "ptz:0" "blobfinder:0"]
      provides ["fiducial:0"]
    )

Author
  Andrew Howard

Last updated 12 September 2005 21:38:45