Multisensor Metrology Comes of Age - Platform Convergence

As mentioned previously, traditional vision based measurement platforms have incorporated multiple types of sensors for years. You might call them the original multisensor platforms. Some high-end systems, like the Brown & Sharpe Optiv, are literally bristling with four or more different types of sensors, from vision to touch and various types of contact and non-contact scanning probes.

Recently with the advent of interchangeable non-contact probes for traditional CMMs, you will regularly find CMMs of all sizes and configurations from small bridges such as the Brown and Sharpe Classic to the largest gantries  such as the DEA Lambda sporting touch, analog scanning, laser line and even video probes on the same system.

The Optiv's multisensor platform that includes (left to right) touchprobe, camera and white light sensor

In many cases, similar or identical sensors are available on both platforms.  Basic sensor types that may appear on either type of platform include:

• Vision: A camera based sensor that measures using the pixels in the camera image.
• Touch Trigger: A sensor that returns a single measurement point by touching the part
• Analog Scanning: A sensor that moves a tip over the surface of the part and returns a dense line of measurement points.
• Laser Point: A non-contact sensor that returns single points of data via a laser beam.
• Laser Line: A non-contact sensor that sweeps a laser line over the part to return many points of data.
• White Light: A non-contact sensor that uses a focused white light (light of all wavelengths) to return a highly precise measurement point of a fine surface.

It might seem obvious that if your system has multiple types of sensors that you ought to be able to use them in a single inspection program—leveraging the relative advantages of each type of sensor on a complicated part. However, this has not always been the case, either because the software could not support a multiple sensor setup, or the hardware could not, requiring multiple controllers on the same machine.

It is also generally the case that each type of platform still has its “optimal” uses. The Optiv series is much better than a CMM for smaller parts where the majority of features are two-dimensional whereas the Brown & Sharpe Global CMM series is better for parts that are on the larger side and have three dimensional features on multiple faces. However, with the advent of multiple sensors, it is becoming more common that the capabilities of the two types of platforms are becoming more and more similar. Since this is the case, smart users are learning to leverage the benefits of both platforms and in some instances, even use both platforms in combination on the same parts.

Ask us how multisensor technology can benefit your business.