GIS into Revit using Dynamo

Revit does not have a import function for a GIS ESRI Shapefile. There are multiple work follows of using MAP 3d or Civil 3d and then importing a .dwg into Revit. Dynamo and the package of GIS  now allows the import function of points, curves and Polygons. The current Package on Dynamo only imports the geometry with in the Shape file and not attributed information, this is currently not available with in the GIS package.

The image of the Dynamo script below uses GIS package in Dynamo to read the shape file and insert point families into Revit. As noted before only the point and curve geometry is import into Revit, no attributed data. The Points are matrix transposes the point to suit the Revit base point to insert point base family in the correct location.

The above appears to be complex set of node but real are just a simple connection of node that performs a simple task; 

1. Read the ESRI Shapefile

2. Process the ESRI Shapefile into list

3. Get the Project Base Point and rotation

4. Matrix transform the point form the Project base point

5. Insert Point family from the transformed base points

The above image is a group of nodes to read the ESRI Shapefile

The process in the above image includes to read the entries of the points with in the Shape file. The result of the list on points is need to be inserted into the Code block to list

Group of nodes to get the project base Point.

The next node group is thanks to Wikipedia! If you can under stand Revit shared coordinates well try think of it backwards!!!

Revit's project base point is the mathematical set out point of the graphical data base. The project base point removes large numbers from the data base and makes the math simple. I actually don't know how to write it in words but to put it simple if you had the option of x =235982030, y=230923092, Z=14000 vs  x=1, y =1, z = 1 for every point as a reference point which one would you chose?  Well Revit makes it simple by using 1,1,1 and tell base point is the large number which is multiplied by linear algebra.  To get the reverse into Revit from Dynamo you need to take the points that you have and Matrix transform them from the Project base point and rotation to true north. Year 12 linear algebra, comes to mind.

Refer to the Wikipedia for Matrix transform https://en.wikipedia.org/wiki/Transformation_matrix

Rotation[edit]

For rotation by an angle θ clockwise about the origin the functional form is  and . Written in matrix form, this becomes:^[4]

Simple math but complex to get at the start. 

Once the Points have been reversed transform then can been used as points with in Revit

Download the updated dynamo script Link

Download the shape file Example Link

Stadium Station

Its been a long time since I've posted any thing new on my blog. I've been locked away working on a great project, which I would like to share with you.

This Video is just a small clip of the over view of the Project. 

Copying Coordinates System

A couple of years ago I wrote about how to create a local grid system for Perth coast Grid PCG94. You can copy the user definition of grid system from PC to PC using the following workflow, which Civil 3d, Map 3d and Infraworks access to the copied grid system.

The PC that does not have the defined Local grid system will need to configure Civil 3d or Map 3d to allows a definition of the grid system to be copied from PC to PC. The copied coordinates system will now be available in Infraworks. 

• Set your workspace to Planning and Analysis
• On the Map Setup Tab - Coordinate System click on the options (Small little arrow in bottom right-hand corner)

The AutoCAD Map 3d option dialogue box and find the Coordinates system tab.

Coordinate System Definitions Stored in Drawings select Prompt User or Automatically add.

Now open a .dwg that contains the user-defined coordinate system from the other PC that has the defined coordinate system. The defined coordinate system will now be available on the PC that previously missing the user-defined coordinate system including
Infraworks.

You can download a sample .dwg that contains Perth Costal grid here PCG94

Infrastructure BIM model

I've finished up working at DoT and haven't really had time to blog / document about the work flows from the project. The project was a business case for a tack slab through the heart of a CDB. My involvement was looking at the cost impact of existing services and infrastructure. This was done by traditional feature survey and laser scanning of the 22km (500gb of point cloud data) alignment to create a BIM model of existing services, using AS5488 (SUE) classification of subsurface utility information as a base line. Majority of the existing in-ground services where modelled to class C with a couple of major services to class B. The model consisted not only of the existing infrastructure but the proposed light rail infrastructure which was created with multiple software's. 

The simple definition of the BIM process to create the model would be similar to a carpenters set of tools, with each piece of software having its own key use. Similar to how a carpenter uses specific tools to construct a house. 

The exchange process between different platforms was done via landxml. 
A simple list of the software's used and their function. 

• Bentley Rail used for the rail design
• 12d used for the road design
• Civil 3d for the existing surface and existing utilities 

The large data set of the point cloud was processed using Recap which reduced the file size of the point cloud data from about 500gb down to 150gb. Which had the point cloud data set usable on a 22km alignment. 

All of the above was placed into navisworks to run multiple rules to determine the impact of the light rail on the existing infrastructure with the results exported to excel to be processed and costed. 

This Video below and what has been described above is only a snippet of what was done. On the bottom of the screen each service is colour coded.

Some of workflows I've blogged about already and have many more work flows to come.



Magic of PI and rotation of City furniture

Infraworks can take a 2d block in CAD software and create a 3d model with the easy of converting the block into to a GIS data set. 
The workflow for Infraworks City Furniture that is from a SDF with a value the represents it orientation in space. Mapexported angle are convert from Degrees to radian during the export process.  Infraworks does not have the following expression Functions:

• PI (3.141592653589793)

or

• RAD2DEG

Therefore to convert radian to degree is a bit of rough approach.

PI as a fraction is 245850922/78256779= 3.141592653589793
Radians to Degrees is "Segment Orientation" x (180 / PI)

A survey file with multiple blocks that represent each feature on a site. I want those site features in my Infraworks model. You can do a simple mapexport from Civil 3d or Map 3d and create a SDF file with each block classified by either layer name or block name. This simple process is great for feature elements that don't had a rotation. If survey file has not got the rotation that represents its true orientation a manual process will need to be done in Civil 3d or Map 3d. Below is a survey block of a traffic light with a rotation that represents it orientation.

Mapexport with the rotation of the block exported. The exported values for rotation end up in radians.

 Example of the traffic lights imported into Infraworks as City furniture with the Z rotation not yet assigned. Notice the traffic lights not oriented correctly.

PI or RAD2DEG are not recognised as expression values therefore to convert radian to degree is a bit of rough approach.

PI as a fraction is 245850922/78256779= 3.141592653589793
Radians to Degrees is "Segment Orientation" x (180 / PI)

In in the expression editor this would looks like

 ROTATION  *  (180 / (245850922/78256779))

Example of the traffic lights imported into Infraworks as City furniture with the Z rotation assigned. the traffic lights are now orientated correctly  

Creating Project Grid PCG94 - Perth Coast Grid

The Work flow for Creating a Project Grid system in Civil 3d 2014 that can then be used across other 2014 Autodesk platforms, example Autodesk Map 3d, Autodesk Recap Pro and Autodesk Infraworks.

To create a Project grid you need to obtain the parameter that define that grid system. The example below is base on Perth Coast grid 94. Landgate and MRWA have the parameters to define local gird for area through out WA. Landgate have the details here for PCG94.

First to Create a Project grid in C3D use the _MAPCSCREATE. Follow the prompts. 

Start with a coordinate system.

The System is to be a Projected system.

Name the Project Grid System.

Base the System off GDA94.

Enter the Parameter that are found on Landgate website.

Review the Parameters and Click save.

Key Points

• Use the exact numbers for the Parameter data. Do not round the data.