Clash Detection using Navisworks Manage

By Chris Smith

Introduction

When we create factory layouts using the Factory Design Utilities tools, we may need to verify our design before we commit to any physical work. Navisworks Manage has tools built into the software that allow users to test for any clashes within the design to prevent costly mistakes or delays.

Static Clash detection

The first option we have is a static clash detection. This option will allow the user to select objects within the workspace to compare against each other for any surface cross over, or “clashes”. This option can be useful for simple studies, like testing production machinery will fit into a room, or if holes need to be made in existing walls for conveyor, ducting etc.

Animation Clash detection

The second option we have is an “animation” clash detection. This option allows the user to apply the clash detection study between 2 objects and apply an existing animation timeline to the study. This allows the software to take multiple studies at set time intervals throughout the animation. This option is useful to ensure moving machinery do not clash part way through its range of motion, like a slewing crane arm erection steelwork, or installation of machinery into an existing building.

Example

For this example, I will be looking at the first option, Static clash detection. This option will show all the skills required for a static study, but can be used in the animation study with a few extra steps. We will look at the animation study in another blog.

We currently have several production machines already situated in another site. The machinery will be repurposed into an existing factory, where an old production line has been decommissioned. The aim of the study is to ensure that the installation of the machinery does not need any special requirements and can be installed without unforeseen issues and delays.

Setup

Below is the existing layout of the secondary site. The machinery we will be repurposing are highlighted in GREEN.

• CNC 2.5 axis Milling Machine x2
• CNC Lathe x2
• 80T Power press x2
• Automatic Band Saw x1
• Laser Profile cutter
• Automatic Pallet Wrapping Machine

At this point in the layout stage, we do not currently have a layout of our existing factory where the machinery will be added. To help with the initial layout process we have had an internal point cloud scan created of the existing factory. Below is an image of the scan in Autodesk Recap.

The scan also contains 360^o images, which can be displayed in “real view” in Recap to further help in creating our existing factory layout.

Attaching the point cloud data in AutoCAD Architecture allows me to add in some external walls to help with the layout process. I can then send the file to Inventor to place the existing assets.

We can use the Point cloud data to create our existing layout from system assets.

Now we have our existing layout I can use the simplify tool to simplify the factory layout into a single ipt file. This should help to speed up downstream processes.

With a “New” layout created for the simplified file, I can add the small factory assets into the layout.

With the “new” assets added to the layout, we can transfer the file back to Inventor. While we were creating the layout, another team member has been creating the architectural model in Revit. With Autodesk AnyCAD we can add the Revit model into the Inventor environment.

Static Clash study

Now we have all the associated files, we can send the model through to Navisworks to start the clash detection process (I have hidden the roof objects).

For the stationary study I am testing the machinery against the building to make sure there are no issues. Before we start the clash detection however, we can group objects into “sets” to make things a little easier. In the View menu, we can turn tool windows on and off. For this step we will need the Selection Tree and Sets turned on.

Using the selection tree, I can pick the top branch of the Revit file. This selects all the objects contained in the Revit file like walls, floors, pillars etc.

Then selecting the Sets tool, we can create a new set from our selection and rename it.

We can also select objects in the graphic window by selecting with the mouse while holding Ctrl. I will use this method to create 2 additional sets. 1 for the existing machinery and another for the proposed layout. I am not selecting any “movable” assets like bins or workers as these objects are not permanent and can be easily moved in real life. This will help to reduce the study calculation times.

Now we have our sets we can create our clash study. You can access the clash detective from the home tab on the ribbon. Once the tool windows open, we can add a new test.

The next step is to define which objects will be tested. We can change the selection options to display our sets instead of picking objects from the list. Once you have selected the objects to test, we can click run test to get the results.

From the results screen we can see that there are 7 clash issues, and the graphic display highlights them in green. We can see from the image below that the layout didn’t take the pillars into account when we created a rough building in ACAD Architecture.

Moving the items away from the wall a little will fix the clashes.

Hopefully you will find this workflow useful. If you have any questions about Autodesk products, please do not hesitate to contact us at customer.services@cadline.co.uk