Smoothing Distance

Last Updated: 30 August 2018         For: OptiSurface Designer

Smoothing Distance (m/% or ft/%)

Defines how rapidly the slopes can change. This effectively smooths the surface so the grade changes do not change too rapidly e.g. from minimum slope to maximum slope in a short distance. A typical value is 100 m/% (300ft/%) but depends on how much soil you want to shift versus how smooth you want the finished design. The grade changes are calculated at every grid point.

For example, if the calculation grid spacing is set to 10m, and Smoothing Distance is set to 100 m/%, then at each grid point the slope can change a maximum of 0.1% (10/100). Eg from 0.1% to 0.2% at one grid point, then the next grid point it could go from 0.2% to 0.3%, etc Note: You need to tick the tick box ‘ON’ to adjust the value and use this constraint in the calculations.


Existing Topography

Proposed Topography V01
Calculation Grid Spacing: 10m
Smoothing Distance: Ticked OFF (No smoothing)

Proposed Topography V02
Calculation Grid Spacing: 10m
Smoothing Distance: 50 m/% (Main Slope and Cross Slope)
Ridge Subzone added

Smoothing Distance should always be included in any design. Otherwise you will get a rough result and the field will not drain well and OptiSurface will get blamed when it is actually a poor designer.

Any design under 100m3/ha should have smoothing increased to get earthworks up to at least 100m3/ha.  Any designs with earthworks above 100m3/ha before smoothing should have smoothing increased until earthworks increased at least 20% and maybe more.

We typically increase smoothing gradually and earthworks will increase gradually then when we push smoothing too far, earthworks jumps up rapidly. So then we back off the smoothing a little and go with that.

Tips and Tricks

  1. NRCS SCS Engineering Field Handbook
  2. Water Control Structures
  3. Smoothing Distance
  4. Erosion Control Banks & Waterway
  5. Drainage Design Solutions of Different Topographies
  6. Runoff vs Slope
  7. Trimble Field Level II Do Not Show the .gps File
  8. Minimum Recommended Smoothing Distance For Export To Trimble Field Level 2
  9. GPS Base Station Setup For Best Vertical Accuracy
  10. How to Survey with Trimble FMX
  11. How Easy is OptiSurface to Use for the Average Farmer?
  12. Balancing Earthworks in the Field
  13. Landform Design Slopes and Smoothing
  14. Export Proposed Topography to AutoCAD
  15. Surface Irrigation Designs with Variable Slope
  16. OptiSurface Designer Import and Export Format
  17. Importing Multiple Survey Files to OSD
  18. Can Drone Or LIDAR Surveys be used with OptiSurface?
  19. Calculation Grid Spacing and Export Grid Spacing
  20. How to Survey a Field for Landforming Design
  21. Loading .gps File in FMX
  22. Designing a Field in Sections
  23. Using an Old OSD File versus a New Survey
  24. No Master Benchmark on Imported Survey File
  25. Displaying Secondary Benchmarks
  26. Import Error for xyz File Due to Encoding Format
  27. OptiSurface4D: Bounded By Ridges
  28. Can OptiSurface handle curved rows in Drainage Analysis & Runoff Analysis?
  29. Reverse Grades to Main Slope
  30. Measuring Culvert Invert Level
  31. Surveying a 1000-Ha Field
  32. GPS Coordinate System Check
  33. Does A Normal UTM Zone Coordinate Need To Be Trimmed To x Digits?
  34. Can You Import Data Directly From GPS System?
  35. Converting Latitude/Longitude to Easting/Northing
  36. Surveying With Any GPS Equipment and Exporting to a gps file for the Trimble FMX
  37. DGPS Post Treating System with 5cm Precision For Landforming
  38. Exporting to Trimble FMX Field Level
  39. Can I Survey with a GPS System on an ATV?
  40. Standard NMEA GPGGA txt File to Import into OptiSurface Designer
  41. 900 Acres: Cut that large survey down.
  42. Export Options for Data Layers
  43. Import Two or More Survey Files to Reach Minimum Area
  44. Different Row Slope Directions In One Field
  45. Does OptiSurface allow for multiple grade breaks per design, taildrains roads, pads etc?
  46. Can I View DTM/Topography In Plan View Or 3D Type View When Doing A Design?
  47. Adjust the Bands in the Legend
  48. Design for a 1000-Ha Field
  49. Would It Be Possible That The Numbers In The Boundary Zone Appear In The New Subzone Created?
  50. Grade Of Best Fit And Splitting The Field Into Boundaries
  51. Acceptable Minimum Slopes
  52. Incorrect Area in OptiSurface
  53. Valley Subzone Not Behaving as Expected
  54. Difference Between Breaklines And Subzones
  55. Alignment of Furrow/Bed Direction with OptiSurface Design Mainslope Direction
  56. Subzones Settings Over Ride Boundary Zone Settings
  57. Printing the Maps
  58. Print Size

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