Trimble Business Center

The create side slope command is a very useful command. I foresee this being a very valuable tool for modeling curb and sidewalks among other things. Thank you for this addition in TBC 5.0.

I have a few comments about the create side slope command:

• Is there way to change the default layer template from 0 to a user designated layer
  • Or to default to the side slope layer
  • 
• The command is erratic when starting at a sharp corner
  • Are there any tricks to control this more?
  • 
  • I would like to be able to set if the template starts diagonally to the corner or perpendicular
    • in the above image, have the image start perpendicular to he corner going towards the 7.35
  • My current work around is to start the template or instruction .5 before/after the corner
    • I tried to starting it just a .1 ahead/beyond the corner but that did not model the sideslope smoothly
    • .5 seems to give enough separation from the corner  that the side slope is modeled more smoothly

Thank You!

Side Slope around Corners

Side Slope Template Layer

I have forwarded to development for review

Alan

Having the Template layer match the SideSlope's layer seems like a good option. I have made that change so next release will work this way.

TBC stores all coordinates in meters and we use a tolerance of 0.0001m when comparing to see if values are "equal". In your template, if the beginning station matches the station of the PI location (within this tolerance) we will compute the cross-section as the perpendicular bisector of the two lines. In your case, just set the starting station to be a very small amount larger than the PI's station (say 0.0005 ft).

If you make the starting station a bit smaller than the PI's station, the cross-section will be computed from the previous line segment and as you said, you will get funny results.

Thanks Gary. 

I just tried your comments and that helped. It looks like around a sharp corner you get more successful results using the template beginning station at whatever the PI plus .01 instead of trying to use .01 plus the PI in the template tables. 

Corner/PI is at 20

Using a template start of 20.01 and no tables

Template starting at 20 and using the tables to control the line starts at 20.01

This yield results that start 5 ft  (the sampling distance) from the PI

I will have Gary look at this Pat - In a corridor, doing the 20.01 in a Table will drop a Section at 20.01 as well as the Intervals of 5 (25, 30 etc.) - that looks like a defect here 

Comment - if you change the first node and you have the second node tied to the first Node using a nominated node (rather than Previous), you dont need to change both line items tables, just the first instruction, and because it is not there from 20 to 20.01 the second node cannot be created there either.

Alan

Yes, there is a small difference between setting the template to start at 20.01 and editing the table to start at 20.01.

When we compute the locations where we compute a cross-section for generating linework, we look at many things to get the list. The first location is the template locations. Then we add the stations of the reference alignment. Then key locations from instructions (which would be the stations in your table) and finally the typical locations.

All of these stations do not get added to the list. We check if a prior station (which has higher importance) is close to this station. If so, the less important station is not added.

That is why when you set the starting station of the template as 20.00 and then edited the table to start at 20.01, the station from the table was ignored (since close to 20.0). So the first location would be 20 (producing nothing) and then the next station would be the station for the typical locations (around 25.0)

If you set your template location to something smaller (like 0.00), then the station from the table would be included.

Thank you for this feedback Gary. I have done some testing with the corridor feature and the side slope feature using your advice and I have found, like you said, that I get better results if I start a template drop at the same incremental value as corridor sample spacing and then add in tables to manipulate linework. 

For the projects I have been working on this has been working rather well but I have a feeling that I will run into instances where you cannot put a drop at a corridor sample interval, DOT projects with obscure typical section changes. If I come across something like this I will make sure to log it and send over some examples.

Thanks for your help!