3D printing, 3D scanning, All

GOM Inspect – Compare CAD model vs 3D scan, in 5 easy steps


In today's post, I would like to introduce you to a very intelligent and simple program for analyzing 3D scans. GOM Inspect software is used in many industries, including Automotiv. With GOM, you can compare the manufactured component with the perfect 3D model. Of course, it has many other functions, but today I will focus on the simplest comparison of a CAD model with a MESH scan. GOM Inspect software is available for free, there is also a paid version of GOM Inspect professional, in the case of simple, single analyzes, it is not needed.

The steps we will go through:
- Description of the program and functionality
- GOM Inspect installation
- Creating the first project in GOM Inspect
- Preparation of input data
- Basing the CAD model to the 3D Scan
- Comparing the elements
- Creation of measurement labels

Have a nice reading
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It is a data analysis software such as 3D scans. Used in quality control, production and product development. With to the available function, the part can be perfectly matched with the part drawing. Analyze all dimensions (2D, 3D, GD&T, SPC). We have the option to create a final report.
Application of the GOM Inspect Software:

- Creating polygon meshes from point clouds
- Processing meshes
- CAD import
- Import of CT Data
- Basing
- Compare nominal data with actual data
- GD&T analysis
- Air profile control
- Control based on curves
- Checks based on points
- Movement and deformation analysis
- Surface defect control
- Parametric Control (GOM Inspect Professional)
- Application learning functions
- Analysis of trends, SPC and deformation
- Virtual measuring rooms (VMR) (GOM Inspect Professional)
- Creating reports
- Digital Assembly
- Next steps in automotive car body
- Smart inspection

Installation of the GOM Inspect software (free version)

The first and most important thing before starting work is to install the GOM Inspect software. If we don't have it. It can be download and install. It is also possible to work in the program in many other languages.

The hardware requirements are not excessive, so there should be no problems with installation and operation. However, it should be remembered that when processing larger models, especially scans with a very extensive mesh, you must have a computer with a large amount of RAM and a decent processor.
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Prepare input data for analysis in GOM inspect

In order to start work, we need to prepare a mesh and our perfect CAD.

Scans are most often in .stl or .igs formats, and this will be the right one for GOM. However, our ideal CAD model should be in the .stp or .step format.

The print was made on the Ender 3 printer. Then it was scanned with the Shining Einscan Pro scanner. With this, we will be able to check the quality of the print made on a 3D printer.
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GOM Inspect - start

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Step one: creating a GOM project

After starting the program, we see a screen with six buttoms to click. These are the main steps. We are interested in creating a new project. At the top of the program, we have a few options used in model analysis. It makes no sense now to write down what they are all for, it is best to describe the functions used during work.

Step Two: Input

Adding our data for analysis is very easy, just put it from the marking to the main program window.
After putting, It will show us on the left a tree with CAD and MESH. We also have all the operations that we add to our model saved there. It can be, for example, labels, homing, constructed elements and coordinate systems.
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Step Three: Initial Basing

After adding the CAD and Mesh model, set them to best fit each other. This is necessary for our comparison of two objects to make sense. GOM Inspect allows us a very large possibility of matching elements. In this article, I want to present the general operation of the program, so I will write a separate entry on the base.
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Step Four: Comparing the Elements

As soon as we have everything set up. We can proceed to analyze the performance of the part. For this operations, we can use CAD inspection. We have a choice here. Whether it is to be done over CAD or Mesh. This differs in the direction of measurement. It is best to choose CAD as the base element, the distance from it was measured.
After selecting this option, we will see a window to choose from several options. Here you can set the maximum displayed deviation. Scales of distances and angles.
When we click ok, the CAD color grid will appear. The mesh will remain visible so in the tree on the left you can extinguish it. We will see a color palette distributed over the CAD element. On the right, we can change the color scale. So that you can better see the imperfections of the item.
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Step Five: Adding Labels

To check specific areas of an element more precisely, you can attach labels to a point. Select from the inspection bar -> deviation labels. At this point, GOM prompts us to press CTRL and left-click on the area of ​​interest. This will show us the numerical value of the deviation in a given place. This is a very useful option. You can easily see the deviation from the nominal size. So we can check the quality of the element we have printed.
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In this post, I wanted to show you in general where you can use the GOM Inspect software. In the next posts, I would like to delve into the specific functions of the program. Its possibilities are enormous, so it can be used in many places.

Thank you for your attention and invite you to the next entries in this topic and to like our page on Facebook