Note: This functionality is only available in AutoTURN and AutoTURN Pro.

Draws sight lines on 2D turn simulations or horizontal alignments based on the location of the driver's eye within the vehicle as well as stopping sight and interval distances to determine the areas in which obstacles cannot be placed.

Note:

• This tool requires an existing 2D turn simulation or CAD geometry in the drawing to act as the path elements. The geometry may consist of lines and arcs, a polyline/complex chain, or an alignment. Lines and arcs cannot be combined with polylines/complex chains or alignments to make up the path elements.
  • If the pre-drawn path elements consist of lines/arcs, select the path elements in the desired direction of travel, and then click a blank spot in the drawing.
  • If the pre-drawn path elements consist of a polyline/complex chain or an alignment, select the path element nearer to the start than the end.
• The driver's eye location is assumed to be coincident with the path when path geometry is selected instead of a simulation and therefore some of the driver's eye location settings are not available in the dialog boxes in those cases.

Analyze Sight Lines - Horizontal Alignment Dialog Box

Driver's Eye Settings Section

Driver's Eye Location

Choose whether the driver's eye is located in the center of the vehicle or to the left or right of the center.

Distance from Driver's Side

This edit box is available when the Driver's Eye Location is set to either Left or Right.

Sets the distance from the driver's side of the vehicle measured towards the centerline of the vehicle.

Distance from Vehicle Front

Sets the distance to the driver's eye measured back from the front of the vehicle.

Sight Line Settings Section

Choose how the length of the sight line is measured, and then specify the length in the box on the right.

• Stopping Sight Distance

Sets the length of the sight line representing the distance required for the vehicle to come to a complete stop (for examples of stopping sight distance values, see Appendix -> Examples of Stopping Sight Distance Values).

• Line of Sight

Sets the length of the straight line segment joining the vehicle position (driver's eye) to the target point ahead.

Interval Distance

Sets the frequency of placed sight lines in the drawing.

Sight Line Draw Options Section

Set which elements to draw as well as the element's color and line style as applicable for each element.

Sight Lines

Sets the color and line style of the sight lines in the drawing.

Summary

Select this checkbox to place a summary of the driver's eye and sight line settings in the drawing and set the color used for the summary.