Roadway Standards - Configure

 

AGi32 provides several roadway standards to chose from when specifying a roadway calculation grid. However, the user may also define a "custom" standard by clicking the Configure button in the Calculation Points - Roadway Luminance - 3 Pt grid dialog. This opens the Roadway Standards dialog. You may start with any of the existing standards, modify point spacing, observer location, and other characteristics, as well as the metrics to include in the custom standard. This new standard is then saved for future reference and use. Use the following steps to modify an existing standard to become a custom standard.

  1. Begin by selecting the standard that you wish to modify from the drop-down Roadway Standard menu.
  2. In the upper-left corner of the dialog, select to Show Units in Meters or Feet.
  3. Select either One Direction Only or Entire Roadway for the across-road span of the calculation grid(s) in your standard.
  4. Select the side of the road that the driver will be on, left side or right side.
  5. The Luminaire Cycles button will open the Luminaire Cycles dialog. This dialog only applies to Roadway Optimizer, but its attributes may be set here.
  6. In the Calculation Metrics, left side of dialog, the metrics included in the standard that you are starting with are listed. Click the Configure button below the list to open up the Roadway Standards - Calculation Metrics dialog. You may include as many or as few of these metrics in your custom standard as applicable. Place or remove checkmarks as appropriate, and then click OK to return to the Roadway Standards dialog.
  7. Click once on one of the Calculation Metrics to give it focus. The top metric is selected by default. Depending on the standard that you started with and the selected metric, you may be able to adjust the height of the calculation grid above the roadway.
  8. If you selected Veiling Luminance, you will options that apply to this metric only, including Observer Age, Windshield Cutoff Angle (measure above horizontal), and the Observer's Vertical Line of Sight, measured below horizontal. You may also select whether to calculate Veiling Luminance with initial or maintained lamp lumens, or per 1000 lumens. In some selected standards, you will have an option as to which formula to use. Finally, in some selected standards, you may choose not to restrict the included luminaires to only those that fall between 1.5 and 60 degrees of the observer's line of sigh (LOS). This restriction is selected by default, as it applies to all standards except RP-8.
  9. On the Calculation Grid tab, the point spacing across and along the roadway (carriageway) are defined separately. For across-road spacing, there are three general possibilities:

8. For along-road spacing, there are two general possibilities:

9. On the Observer tab, select where the Observer(s) will be located:

10. Repeat steps 6 - 9 for each of the Calculation Metrics listed on the left side of the dialog.

11. When you have finished specifying the parameters of your custom standard, click on the Save Changes button. You will be prompted for a name. You will not be allowed to overwrite an existing standard, but you can save the changes under a new name.

The custom standard that you created will be available for future use by selecting it from the Roadway Standard menu in the Calculation Points - Roadway Luminance - 3 Pt grid dialog.

 

* IMPORTANT: Regarding the Observer position, it is important to note that the R-Tables are based on empirical data for an observer with a viewing angle of 1 degree below horizontal. If the Observer's height or distance from the grid points changes, this will affect the viewing angle. Small changes will have small effects, but larger changes could invalidate the calculation.