REVERSE ENGINEERING

For us, the digitized component represents the basis of re-engineering.

Through a CAD-supported surface redesign of the digitized grid lines (3D scan in STL format), our engineers transform them into CAD data sets suitable for production .

REVERSE ENGINEERING PROCESS

 

Depending on the application, either a pure surface model or a parametric solid model is required.
Therefore, there are two options for re-engineering:

VERSION 1: CAD REDESIGN (rebuild)

 

GENERAL

 

Our engineers redesign the component in CAD – the parametric surface redesign.
The 3D scan (STL) only serves as a template.
The resulting volume model (STEP) can be edited in any CAD software. Alternatively, we also offer a parametric model with a history in the CAD program of your choice.

 

 

APPLICATION CASE

 

  • Parametric model

  • Volume model | Solid | part

  • FE Analysis

  • 3D printing

  • CNC milling

 

 

PROCESS

 

  1. 3D scan serves as a template / reference for the newly built model

  2. CAD model is built from basic geometric shapes (points, lines, circles) ("solid modeling")

  3. Component features such as dividing lines, draft angles and fillets are stored in the construction tree

  4. Measured values ​​from the scan (eg odd hole dimensions, flat surfaces etc.) are interpreted meaningfully

 

 

RESULT

 

Parametric, associative CAD model with mathematically correct, qualitatively perfect surfaces.

 

 

BENEFITS

 

  • Editable CAD volume model including construction history ("construction tree")

  • Component can be optimized / changed / further developed

  • CAD data in connection with 2D drawing derivation optimal for component production

 

 

DISADVANTAGE

 

  • Deviation from 3D scan due to new construction can - depending on the application - be greater than with AutoSurface (approx. 0.1 - 0.25 mm); no functional impairment

  • Redesign, especially with free-form surfaces, is sometimes very time-consuming

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3D SCAN

Polygon mesh / facet model (STL)

3D surface scan of the original component.

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CAD MODEL

Parametric surface model

Native, redesigned surface model in CAD. Qualitatively perfect surfaces with wall thickness.

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COMPARISON

Functional component

Slight deviations between 3D scan and Auto Surface.

VERSION 2: AUTOMATIC SURFACE REDESIGN

 

GENERAL

 

This surface return is an automatic impression of the underlying 3D scan (STL). An algorithm calculates the NURBs surface model (STEP).

 

 

APPLICATION CASE

 

  • Surface model, 3D printing feasible, CNC milling

 

 

PROCESS

 

  1. The 3D scan (STL) is loaded into the reverse engineering software.

  2. The number of NURBs areas is determined from which the resulting area model (STEP) is to be built.

  3. The reverse engineering software creates a direct impression.

  4. The holes in the network are closed manually.

 

 

RESULT

 

Non-native CAD model with precise but qualitatively moderate surfaces.

The deviations from the 3D scan (STL) range from 0.01mm to 0.05mm. This surface model is only suitable for organic shapes without edges and holes.

 

 

BENEFITS

 

  • Very little deviation from 3D scan (+/- 0.01 - 0.10 mm)

  • Faster, less expensive automation for organic shapes without edges and holes

 

DISADVANTAGE

 

  • Very fine-meshed, large STEP files that can cause problems when used again

  • Many surface defects / holes that may have to be filled manually

  • Therefore CAD post-construction is often faster and cleaner

  • No native data available

  • AutoSurface takes over errors in the 3D scan

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3D SCAN

Polygon mesh / facet model (STL)

3D surface scan of the original component.

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AUTO SURFACE

NURBs surface model (STEP)

Non-native CAD model thanks to automatic surface return. Qualitatively moderate surfaces.
No wall thickness.

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COMPARISON

Functional component

Slight deviations between 3D scan and Auto Surface.

CONCLUSION

 

MANUAL CAD REDESIGN VS. AUTOMATIC REDESIGN

 

We recommend – especially with functional components – the manual CAD redesign option.

Reason: Only with this process, smooth production and perfect component function can be ensured .

 

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3D SCAN

Polygon mesh / facet model (STL)

3D surface scan of the original component.

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CAD MODEL

Parametric surface model

Native, redesigned surface model in CAD. Qualitatively perfect surfaces with wall thickness.

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REPRODUCED COMPONENT

Functional component

Smooth production and perfect component function from a CAD data set.

REDESIGNED PARTS | COMPONENTS