Exploring 360º Mesh Data Generation for Multi-Sensor Layouts

Gocator® software now supports 3D mesh data generation for advanced shape measurement and inspection of multi-view 360º surface scans. Mesh data consists of “stitched” scans from multiple sensors. The result is a 360º Mesh of the object that can be used for measurement with other surface tools.

Application Example

For our application example, we will take measurements of multiple features on the surface of a pipe fitting.

PipeFitting

Step 1. Perform High Accuracy 6DoF Alignment

Leveraging six degrees of freedom alignment, you can now generate these high-accuracy 3D Mesh scans from ring multi-sensor layouts. To perform alignment, we first set up 4 sensors in a ring layout and scan an alignment target.

Captured data from each sensor is displayed simultaneously.

Calibration Target Scan Split 0 1

NOTE: One of the main advantages of this process is that you don’t need to worry about physically aligning the sensors to get overlapping laser planes. Physical alignment is error-prone and very time-consuming, which is avoided entirely with Gocator’s high accuracy 6 DoF alignment approach.

Now we add a Surface Align Ring tool to calculate the transformations for our 4-sensor ring layout with 6 degrees of freedom. The results of this high accuracy alignment are saved in an XML file, and include compensations for X angle rotations.

We then load the XML file in a Surface Mesh tool, which stitches the scan data from our 4-sensor ring layout into a single mesh, or 360º scan.

Step 2. Scan the Pipe, Apply Aligned Transformations, and Extract Mesh Surfaces

Next, we scan the pipe fitting with our ring layout multi-sensor system and apply the same aligned transformations to the data that we established in the previous step. The result is a 360º Mesh of the pipe fitting, aligned with 6 degrees of freedom.

SurfaceMesh 3Ddata

Now we want to apply measurements to multiple features on the 360º surface of the pipe (including the radius of the straight section of the fitting and the radius of bottom opening).

To do this, we simply apply the Mesh Projection tool to set a plane angle to project our surface data from. The benefit of this tool is we are able to extract any number of surfaces from a single 360º Mesh scan. The projected Surface data can then be used as an input for any Surface tool.

MeshProjection

We also have the ability to apply dedicated Mesh tools directly to raw Mesh data (e.g. for dimensional and deviation measurements), such as the Mesh Plane and Mesh Bounding Box tools.

Step 3. Apply Surface Measurements to the 360º Mesh Projection

Now we can apply measurements to our multiple features of interest. First, we apply the Surface Cylinder tool to the top surface of the pipe fitting, using separate instances for each radius we want to measure.

Surface Cylinder Pipe Split 0

Next, we want to measure the feature on the bottom of the pipe fitting. To do this we simply add a Surface Circular Edge tool to determine the internal radius of the opening.

Surface CircularEdge Pipe Split

To determine the external radius of the opening, we simply duplicate the tool and change the search direction to inward to generate our measurement result.

We can add other Surface tools to the projected data in the same way, allowing for advanced measurement on the sides of objects or any other perspective we require.

To explore more features in the latest Gocator software, visit the firmware section of our website.