Helmel has integrated the Renishaw UCC2 controller into it's full DCC style CMM product line. By doing this, we expand our capabilities to include analog scanning probes to compliment the touch trigger probes. The UCC2 is compatible with the I++ / DME Initiative that brings common platform support for a wide variety of CMMs and manufacturers.

This system is targeted toward reverse engineering and to provide enhanced inspection tools by capturing larger data point clouds for a more accurate inspection process. Helmel's own Geomet Universal CMM Software has evolved to include the full power of the UCC2 with the ease Geomet is famous for.

Scanning Technology

The UCC2 has native support for the SP25 scanning family. Scanning is best controlled, not by the host software such as Geomet, but in a closed loop between the scanning head feedback and the motion controller.

The UCC2 has its own proprietary controller system that responds to the feedback from the scanning head. The change in stylus contact with the surface being scanned is fed back into the controller in real-time and from that information, the motion controller guides the CMM along a path that keeps the probe in contact with the anticipated surface.

This sampling is done at such a high rate that you can scan in excess of 100 mm per second on uniform surfaces. The scan speed is adjusted downward to accommodate uneven surfaces that required a tighter motion control to follow it. While this motion control sampling is happening, the UCC2 is also capturing and sampling data points at predetermined pitch values. On uniform surfaces, it is common to capture thousands of data points in a few seconds. With this increase in data point capturing you are assured of a better representation of the surface and its nuances to form.

The example above is a port on an engine head that required the UCC2 to scan in patches as the head is rotated within the CMM on a special U/V Axis Table and under the control of Geomet. The benefits of this setup is that the data points remain stable in the Part Coordinate System, which articulates with the change to the position of the U/V Table.

To better understand the benefits of the U/V Rotary Axis Table, please click here.

The data point clouds shown above is exported into a CAD-CAM system for processing directly into tool paths for replication.

Inspection Benefits

Not all applications require a concentration of data points as illustrated above. However, capturing data clouds on prismatic features provides you with a better understanding of what the feature looks like. For example, taking 10 points on a basic 4".00 diameter circle producing a fairly reliable size and position, but lacks the data point concentration to determine it's circularity.

In today's world, it is no longer acceptable to use minimum data points to determine a feature. Engineers are now asking where the form deviates and how it can affect product operations. Take for example a cylinder that houses a pressed bearing. If the cylinder had a typical triangular internal shape, that force applied from the three fluted surfaces onto the pressed bearing will also deform the bearing and reduce its service life.

However, scanning the internal surface of the cylinder with a helix scan that captures data points all along the surface will then show the form shape when passed into a form analyzer such as the Circle Profile Tool in Geomet.

Geomet and the UCC2

The power of the UCC2 can only be accessed by efficient and user friendly CMM host software. Geomet has carved out a niche in the inspection world as a user friendly and powerful software package. It only became natural that Geomet would apply its basic concepts and experience to accessing these new and powerful UCC2 tools.

Using the Circle Generator as an example, we have expanded its use by adding a simple check box to the generator that switches from touch probe operations to the scanning process. The benefits to the user are immense by not having to learning new scanning tools for every feature.

There are special scanning tools that perform contour following on open and closed surfaces. These deliver data cloud sets and Cardinal Splines for use in model comparisons and reverse engineering.