Create a Formation Surface for a Platform in Civil 3D

Civil 3D has some powerful tools for earthworks, through the use of surfaces and grading objects. In the next few lines, we will use an example to illustrate a workflow for a common scenario.

In this example, we have a survey for the existing ground (EG) and we want to designa platform. We need to discard the upper layer of topsoil from the existing ground and there is also a minimum depth from the finished platform to underside that we must meet.Our goal is to combine this information to obtain a surface with the levels of the proposed formation, which will be the starting point for the fill to take place.

To obtain that surface, we need to select the minimum level from the Base of Platform and the EG less Topsoil surfaces. If we could take only the cut and isolate it from the fill between those two surfaces, we could get the proposed formation by combining the EG less Topsoil surface with the cut obtained as previously described.

There can be several approaches to tackle this problem, I summarise some of them:

1. Create a volume surface between Base of Platform and EG less Topsoil and Exclude elevations greater than 0 in Surface properties, therefore ending up with a surface with cut only. The problem with this approach is that this option cannot be used in the volume surface directly. You will need to extract the triangles from the volume surface (Surface contextual ribbon -> Extract from Surface -> Extract Objects) and then create a new surface from those triangles.

2. Draw polylines for the intersection of both surfaces (Base of Platform and EG less Topsoil) using theMinimum Distance Between Surfaces command (from the Civil 3D Ribbon, Analyse tab, Ground Data Panel (expanded)) and use the polylines that enclose fill areas as Hide boundaries.

3. Compute the intersection between both surfaces as above and create grading groups to complete the surface.

I am going to follow the third method, which allows accurate control of the slopes using grading objects. The step by step process is as follows:

Create a surface for the existing ground (EG) from the survey data.

Create an EG less Topsoil surface by pasting the EG surface into it and offsetting it vertically by the topsoil depth.

• Create a grading group for the platform, selecting EG less Topsoil as the target surface. You will also need to attach a surface to the grading group.

• Create a Base of Platform surface by offsetting the surface attached to the grading object by the minimum depth below platform.
• Compute the intersection between the Base of Platform and the EG less Topsoil surfaces using the Minimum Distance Between Surfaces command.

• Convert the polyline from the previous step into a feature line and complete the area in cut with another grading group (and an attached surface), targeting the EG surface this time. You will also need to place it in a different site, to avoid interaction with the top of the platform.

• The final step to get the finished proposed formation surface is to merge all of the surfaces together by pasting them into a new surface and applying boundaries accordingly. An additional grading object can be added to tie in the EG less Topsoil and the EG surfaces.

The final Proposed Formation surface looks like below in Civil 3D object viewer in our example.

How to Create a Christmas Reindeer With Autodesk Dynamo

I was in our office last week when our marketing team asked me to help them create an Excitech Christmas image to send to our customers using Revit.

After quite a bit of thought, I knew that Autodesk Dynamo would need to be involved to create something a bit more interesting than a gift-wrapped box with a red bow on top!

I hadrecently been looking at the Mesh Toolkit for Dynamo and after a bit of searching, I found a low poly model of a reindeer and tested this with the Mesh Toolkit. Here is how the reindeer appeared when imported into Autodesk Dynamo:  

The next stage was to add a little context and scale to the reindeer. The group below rotates and scales the mesh, and then turns the mesh edges into lines. This then leaves the 3D wireframe representation of the mesh model. 

The wireframe model is then passed into the group shown below to create a structural framing and to ensure the frames are set to centre. I created a custom CHS section with three materials that can have illumination set within the material. 

The second part of the script requires the randomisationof the materials that are applied to each structural section. The first two nodes collect all the structural framing members from the project and then the items are counted. Meanwhile, two materials are called by name and then cycled to generate the correct quantity. The list is then shuffled to randomise the order, and each structural member is then assigned the random material.

Finally, I created a topographic surface for the snow and added some RPC trees from the Revit library. Extra points were added to the surface to represent the appearance ofreindeer's footprints. 

The scenes were then rendered in the cloud using the Autodesk A360 rendering.

And there you have it, Excitech’s Christmas Reindeer created in Autodesk Dynamo. See it in action here: https://www.youtube.com/watch?v=Y97GyTmn54o

For more information about Autodesk Dynamo, visit our product page here or get in touch with us by calling 01992 807 444 or emailing marketing@excitech.co.uk

Convert AutoCAD Drawings To A Shapefile Format

AutoCAD is a great tool to edit and manipulate drawings, but sometimes we need to convert the information contained in AutoCAD drawings to a different format to study it from a different perspective. Being able to interoperate between different applications to take full advantage of their differing capabilities is essential and is part of what I cover in my CAD training courses.

An example of this is the shapefile format, which is used in Geographic Information System (GIS) software. GIS applications are used to edit and analyse spatial information and have many applications in fields like engineering, transport or telecommunications.

The MAPEXPORT commandserves that purpose, however is unfortunately not available in AutoCAD. In order to use it, you will need AutoCAD Map 3D or Civil 3D installed. This command is easy to follow but you need to be aware of the differentoptions  to include all the information needed in the shape files.

I will now take you step by step through a CAD training exercise where we export all the features from an AutoCAD drawing to a shapefile format.

First, type MAPEXPORT in the command line from AutoCAD Map 3D or Civil 3D. In the window that pops up, browse to the path in your computer where you want to store the shape files. Select ‘Shape Multiclass’ in the type drop-down and type a name for the folder that will contain the files. A new folder will be created with this name and the files generated will be stored in it. In this example we are going to call this folder ShapeFiles, as shown below:

You can also select an existing folder, but it is not recommendable because it may conflict with existing ones. You will receive a warning message if you try this, and will then give you the option to append the new files, overwrite existing ones that may exist with the same name or cancel this dialog to be able to change to a different folder.

In the next window, go to the Selection tab and click on the ‘Select all’ option to select all the objects contained in the drawing.

There are2 alternatives for manual selection. If you click on the first icon you can click on the objects in the drawing that you want to include. Clicking on the second icon will open the ‘Quick select’ window, where you can filter the different objects by their type and properties.

You can then add additional filters to your selection by selecting the layers or object classes that you want to include. Notice that an asterisk is included in the Layers field by default, which means that all the layers will be included in the filter.

On the Feature Class tab, select ‘Create multiple classesbased on a drawing object’.

If you want to include some particular attributes in the Shape files, this can be done by clicking on the ‘Select Attributes’ button and ticking the ones you are interested in.

Finally, go to the Options tab and tick ‘Treat closed polylines as polygons’. Other options available in this tab givesthe ability to convert coordinates to a different coordinate system, or to choose between 3D or 3D shape files, by clicking on the ‘Driver Options’ button.

If you click OK, a group of files will be created for each feature, as shown below:

You can now open these files directly in your GIS application or add them directly to the central directory of a ZIP archive. The latter makes it easier tosend the information to a third party if needed.

CAD training is an excellent way to brush up on your skills and provides more accurate and efficient ways of doing things on the software.

If you are looking for CAD training, take a look at our full range here.

https://www.excitech.co.uk/Services/Training/Training-Courses?LocationIds=&SupplierIds=&IndustryIds=&ProductIds=&TrainingTypeIds=&OrderByScheduleValue=&OrderByValue=&PageNo=1&StartPrice=&EndPrice=&PageType=&SearchText=CAD&StartDate=&EndDate=

Autodesk Autocad And Autocad Lt Cross Platform Licensing

With the AutoCAD and AutoCAD LT 2019 for Mac release coming much later in the year than the windows version, a common question I get asked is “why are there separate Windows and Mac version releases?”. This is with the understanding that AutoCAD and AutoCAD LT benefit from cross-platform licensing.

Cross platform licensing essentially lets you activate your CAD software on either Windows or Mac operating systems. This applies to versions 2013 or later and also supports subscriptions with multi-user access. Licences used on both Windows and Mac operating systems can pull from the same licences on the network licence server.

AutoCAD and AutoCAD LT 2019 for Windows was released back in March 2018, a full 9 months before the Mac version this month. This is generally due to additional development required to ensure AutoCAD and AutoCAD LT is up to standard, but there is also alignment of the new Mac version with new Mac operating system releases and patches.

This alone does not justify a separate release schedule, so the next point is related to honesty and ensuring customers know what they are actually buying. Let’s say you purchase your AutoCAD subscription immediately after the 2019 Windows release, its’s all branded 2019 and you are thrilled to use all the new tools available. You would be disappointed and feel mislead if upon reviewing your download options, 2018 was still the newest version available. Personal disappointment aside, CAD software features can significantly increase efficiency and productivity – they can also be essential for a specific project, so this may have large ramifications.

The final reason is related to the packaging changes made by Autodesk over the past year or so. It is worth noting that cross platform licensing only applies to the individual products, AutoCAD LT and AutoCAD – where these products are present in Suites or Collections, cross-platform licensing does not apply. So, AutoCAD LT as contained in the AutoCAD Revit LT Suite is only available for Windows. The most recent example of this is AutoCAD Including specialised toolsets. This version of AutoCAD contains all the specific industry toolsets (Architecture, MEP, Mechanical and more). As those specific toolsets are not available on Mac, it would be extremely misleading to sell this as a Mac compatible version.

As two completely differing operating systems, there is bound to be some differences, maybe not in what the software does, but likely in the way it does it.