Hybrid Manufacturing Requires Advanced Inspection Software
Machining excess material to finish hybrid parts requires in-process validation to verify that the part is reaching desired profiles and tolerances.
Hybrid manufacturing, which uses both additive and subtractive methods to manufacture parts, provides a new set of challenges. To produce a part, hybrid approaches involve shaping the part with an additive machine, then cutting away excess material to achieve the desired tolerances. Autodesk’s Phil Hewitt says this creates a need for in-process inspection. According to Hewitt, when a machine switches between two wildly different processes such as 3D printing and milling, in-process metrology is necessary to verify that the part is reaching desired profiles and tolerances. Furthermore, because finishing processes for AM parts require machining excess material to achieve the desired tolerances, in-process validation is necessary for a hefty percentage of mechanical parts produced additively. In-process measurement, however, must contend with the complex part shapes common in AM.
The major hurdle for scanning AM parts is the need to measure a variety of complex shapes, including near-net structures that provide inefficient geometries for touch probes. Near-net parts provide far too many points of contact for the probe to quickly and efficiently establish tolerance for each point. These complex shapes necessitate noncontact measurements, which can include both in-process and out-of-process solutions.
Portable scanners, for example, can gather scan data from multiple angles. Despite relying on human operators, they provide accurate scans of complex parts in much less time than touch probes would take, making them efficient tools for quality assurance. In-process solutions, such as fixed scanner arrays, measure parts from multiple angles mid-process, combining multiple images in scanning software to create well-rounded models of a part. Both solutions provide scan data that is easily comparable to CAD information using tools like PowerInspect from Autodesk.
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