Creating a Rotating LiDAR Sensor

This page shows you how to create a rotating LiDAR sensor that will be used for LiDAR simulation.

To create a Rotating LiDAR Sensor:

  1. From the Light Simulation tab, click System > LiDAR .
  2. From the Type drop-down list, select Rotating.
  3. Define the axis system of the LiDAR physical module by selecting an origin point , a line for the horizontal direction and a line for the vertical direction or click and select a coordinate system to autofill the Axis System.
    Note: If you define manually one axis only, the other axis is automatically (and randomly) calculated by Speos in the 3D view. However, the other axis in the Definition panel may not correspond to the axis in the 3D view. Please refer to the axis in the 3D view.
  4. If you want to create a dynamic LiDAR sensor, in the Trajectory file field, click Browse to load a trajectory file (.json).
    Note: For more information on trajectory files, refer to Trajectory Files.
    When a trajectory file is assigned to a LiDAR sensor and the feature is edited, the trajectory is displayed in the 3D view.
  5. In Firing Sequence, click Browse to load two *.txt files respectively describing the scanning pattern and the rotation pattern of the LiDAR.
    Note: If you need more information on scanning pattern files, see Firing Sequence Files.
  6. Define the axis system of the source (emitter channel):
    Note: When using an intensity distribution file as source, first verify the orientation of the IES file to correctly orient the beam.
    • Click to select one point for the origin (point where the pulse is received).
    • Click to select a line to define the horizontal axis (corresponding to the X axis of the IES file).
    • Click to select a line to define the vertical axis (corresponding to the Y axis of the IES file).
    • or click and select a coordinate system to autofill the Axis System.
  7. Define the spectrum of the source.
    • Select Monochromatic and specify the wavelength in nanometers.

    • Select Library and from the drop-down list click Browse to load a .spectrum file.

      If you want to see the file properties or edit the file, click Open file to open the Spectrum Editor.

  8. Define the source intensity distribution of the LiDAR:
    • Select Library to load an IES (.ies) or Eulumdat (.ldt) file.

    • Select Gaussian to manually define the intensity distribution profile of the source.

      • Set the total angle of emission of the source.
      • Set the FWHM angle for X and Y.
      • In the 3D view, click two lines to define X direction and Y direction.
    Note: If you define manually one axis only, the other axis is automatically (and randomly) calculated by Speos in the 3D view. However, the other axis in the Definition panel may not correspond to the axis in the 3D view. Please refer to the axis in the 3D view.
  9. Define the axis system of the sensor (receiver channel):
    • Click to select one point for the origin (point from which the pulse is emitted).
    • Click to select a line to define the horizontal axis of the sensor.
    • Click to select a line to define the vertical axis of the sensor.
    • or click and select a coordinate system to autofill the Axis System.
    Note: If you define manually one axis only, the other axis is automatically (and randomly) calculated by Speos in the 3D view. However, the other axis in the Definition panel may not correspond to the axis in the 3D view. Please refer to the axis in the 3D view.
  10. In the Optics section, define the properties of the sensor's objective:

    • In Distortion file, click Browse to load an .OPTDistortion file.

      Note: The *.OPTDistortion file is used to introduce/replicate the optical distortion of the lens. Every lens has varying degrees of distortion.

    • Define the Transmittance (capacity to allow the light to pass through) of the lens:

      For a monochromatic source, define a constant Transmittance.

      For a source using a *.spectrum file, click Browse to load a Transmittance spectrum file.

    • In Focal length, define the distance between the center of the optical system to the focus.

    • In Pupil, define the diameter of the objective aperture.

      The Horizontal and Vertical Field of Views (FOV) are automatically calculated according to the parameters of the objective.

      Note: The fields of view are only indicative and will not be used for LiDAR simulation.
  11. Define the Width and Height to define the size of the imager (the sensor) that is placed behind the objective.
  12. When Beta features are enabled, if you want to define the imager resolution, set Resolution (beta) to True and define the number of Horizontal pixels and Vertical pixels.
  13. Define the sensor range and accuracy:
    • In Start, type the minimum distance from which the LiDAR is able to operate and integrate rays.
    • In End, type the maximum distance up to which the LiDAR is able to operate and integrate rays.

    • In Spatial accuracy, define the sampling used to save the Raw time of flight.

      The time of flight is the time taken by the light to travel from the LiDAR to the object.

  14. If you want to define an Aiming area for the sensor:
    1. Set User defined to True.
      In the 3D view, a preview of the aiming area is displayed to help position it to the desired location.
    2. If you want to adjust the axis system (that is, by default, the same as the sensor's), select one point for the Origin and two lines for X and Y directions or click and select a coordinate system to autofill the Axis System.
      Note: If you define manually one axis only, the other axis is automatically (and randomly) calculated by Speos in the 3D view. However, the other axis in the Definition panel may not correspond to the axis in the 3D view. Please refer to the axis in the 3D view.
    3. From the Type drop-down list, select the shape you want to use for the aiming area:
      • Select Rectangle
      • Select Elliptic
    4. Define the Width and Height of the cover lens.
The LiDAR sensor is created and is visible both in Speos tree and in the 3D view. This type of LiDAR generates only one simulation result (*.OPTTimeOfFlight).
You can now create a LiDAR Simulation.