As many know LIDAR is growing momentum as a
way to create and display data involved in a Civil Engineering
project. This data can be very useful, typically in more ways
than one; this is just one of the ways that LIDAR can be used in
a work environment.
When getting LIDAR Data into Civil 3D the
way that is specified in this exercise we must convert a .txt
into a .mdb. That way we can link the data into Civil 3D. The
following steps in this guide will allow us to use this data in
the environment provided by Civil 3D.
1) Converting our .txt into .mdb format
First, we must start Microsoft Access and begin a new file, then
we begin to create a new database by selecting the blank
database from the New File Task Pane.

Continuing, we must browse to a location of
our choice to save this file and name it so that it is familiar
to us. Now we are able to click “create” which will generate our
database. After we have created this, we will find ourselves in
the Database Dialogue Box. We can now right click and Import the
database we just created. Once you select “import” the import
dialogue box will appear and we can import the .txt that
contains our LIDAR data.

Since our data is comma-delimited we will
choose the option “Comma Delimited” in our Import Text Wizard in
order to define our data, click “finish” and then click “OK.”

We have just finished successfully
converting our data into the proper format that makes it
possible to use this data in our projects.
2) Setting up our ODBC (Open Database Connectivity) Data source
linked to our .mdb file
This section describes how to create an ODBC Data Source in
order to link our data into Civil 3D. First we must access our
Control Panel and click on the Administrative Tools shortcut.
Under this selection you will see an icon for Data Sources
(ODBC). We will double-click this to continue.

Under the OBDC Data Source Administrator we
will need to add a MS Access Database. Then under the Create New
Data Source dialogue box, click on Microsoft Access Driver (.mdb)
name, click on finish and the ODBC Microsoft Access Setup
dialogue will appear.


In this box we will browse to the .mdb file
that was created, select this file and it will return us to the
prior box. We will name this database in the Data Source Name
box within the Microsoft Access Setup dialogue box. Once this is
completed, we will close out of the Admin tools. We have now
created an ODBC Data source we will link to inside of Civil 3D.
3) Filtering Data to create a surface.
Now that we have our data source created we can begin to work in
our application. We will start by creating a new file,
preferably from a template that is set up as your company
desires. Once in our drawing, we will need to edit the
coordinate settings to complement our LIDAR data. In the
prospector tab, we can now create a surface that we will name EG
for existing ground and use the style NO BORDER for our display.
Now we can add the desired point file to our surface, so under
the point file option under definition we will choose to add a
point file.

Once we select “add” we will be taken to
the Point File Format Dialogue Box. This is where we will edit
the format to fit our data. In this case we will select the ENZ
(Easting, Northing, Elevation) format and then click copy.

This will take us to where we can edit the
format in which the data is read which will allow us to sync
with the LIDAR data. In this case we will change the format name
to LLZ (Latitude, Longitude, Elevation) Comma Delimited. Now we
can choose the frequency that we want to use to filter our LIDAR
data. Considering that LIDAR contains an enormous amount of
points, we want to filter this data so that it is manageable.
This part of the dialogue will allow us to do this. We now
toggle the Sample Every checkbox and set the frequency of the
point that will be inserted. In our situation we will choose 10
points.

We must now set the Coordinate type in
which we will be formatting our points. We will now go into our
copied Point file format and change the Easting and Northing
Columns to DECDEG Longitude and DECDEG Latitude and we will also
change both precision columns to 6.


This enables us to go ahead and choose our
source file, click browse next to the Source file field and
browse to the location of your saved .txt file, then click OK.
This is where the Point file is read into the definition of the
surface. Now we can use the Zoom to command to see our surface.
4) Using Map Tools to Attach Data to Surface
Using the Map tools in Civil 3D we can attach this data to the
point we have inserted into our surface. We will use the
toolspace within the Map functionality to do so. Under the
Display Manager tab we will choose to connect to data via the
data icon. To the left of the dialogue there will be a section
labeled Data Connection by Provider.

This is where we will choose to add an ODBC
connection. Once we choose to add we will get the option to name
our connection. It would be a good suggestion to name it
something similar to all the files associated with the data.
Once named, we can choose the source. We will click the ellipsis
above the connect icon and choose the name we created for our
Access Database. We will now connect the data via the connect
button .At this point it will ask for a user name and password.
Considering we did not create one you can freely log in without
any information. Once in we will have access to our data and we
can set the coordinate system we wish to apply to this data in
the dialogue.

In our case we will set the data to conform
with info we established earlier in the exercise by matching our
fields in the data with our X,Y,Z Coordinates, Field 1-X, Field
2-Y, and Field 3-Z. We established these fields when we changed
the format to LLZ. Now we can add the data to the map. However,
we only want to see a specified area of the surface that we
created earlier, so we will add this data with a query that
allows us to specify the location in which we can view the LIDAR
data. When viewing the Add button you will notice a pull down
that will allow us to add to the map with a query. In this
instance we will choose the Location property to define our
query. In the Location Condition dialogue we will simply choose
that we want our data to be applied within a rectangle. We can
now define our query. Now we can choose anywhere within the
boundary of our surface to attach the LIDAR points and data. You
must manipulate the style so that these points become visible.
If you select the points and right click and then use the check
out feature they will become MAPPOINT Objects. Once exploded the
MAPPOINT objects will become AutoCAD point objects with X,Y,Z
values, thus allowing you to add the objects to the surface to
create a more in-depth surface in a specified area.
In conclusion, using this LIDAR data will allow us to create and
utilize information with less manpower to gather and manage all
this information that is at our fingertips. This powerful tool
will continue to grow, considering its accessibility within the
civil engineering world. It is an accurate, manageable, new and
powerful way to get faster data without sacrificing accuracy.