Virtual Clamping

Quantum leap

With Virtual Clamping, GOM is currently developing a new technology for the inspection of plastic and sheet metal parts.

Conventional forming processes such as injection molding and sheet metal forming result in deviations from the nominal component specifications. These deviations are commonly referred to as distortion or springback. In the past, components have had to be clamped in elaborate fixtures to compensate for these deviations while taking measurements and to simulate the assembly situation. But with GOM’s newly developed Virtual Clamping technology, this measuring process is set to become much more straightforward.

The Product Management division at GOM is headed up by Dr. Jan Thesing. He has played a major role in the development of Virtual Clamping, and has already completed a number of successful practical tests together with industry partners.

Measuring with clamping fixtures is both challenging and expensive
When it comes to measuring plastic and sheet metal components, it has always been the same old story: if you want accurate measuring results, then you need accurate clamping fixtures. The clamping fixture moves the components into a forced position with the aim of simulating the assembly situation and compensating for the distortion or springback arising from the forming process.

Constructing and manufacturing clamping fixtures such as this is expensive, as the individual fixtures are highly specific and therefore relatively inflexible in terms of how and where they can be used. This is where user influence comes into play, as manual operation of the components causes inaccuracies to arise, and these are reflected in the measured data. It also means the measured data is missing at the clamping points.

Going forward, we will be able to do away with complicated clamping fixtures entirely, which represents a revolutionary step for the field of metrology.

Dr. Jan Thesing, GOM Product Management

Clamping of components to become a thing of the past
With the new module in the GOM software, it is now possible to calculate the clamped state of the real component in its unclamped state. This produces measuring data that is directly comparable to the clamped component. Furthermore it is also possible to make statements about the real distortion or springback without needing to incorporate further measuring procedures. In combination with weight compensation, a new universal pneumatic device offers the crucial advantage that even non-rigid components can be measured independently of the real mounting position.

Virtual Clamping even used for GOM CT
Computed tomography is increasingly used to measure small plastic parts with geometries which are difficult to access with standard measuring machines. As this measuring system is not suitable for incorporating a clamping fixture, Virtual Clamping offers a crucial solution in this regard.