Integrated microwave sensor is the key
The German industrial automation company Festo previewed a novel new pneumatics technology, reportedly the first to feature built-in diagnostics. Engineers achieved this capability by integrating a non-contact, microwave sensor into the end cap of the cylinder, which acts as a waveguide. Much like a radar tracker, the sensor emits short pulses of electromagnetic energy directed at a target (in this case the piston), measuring the time it takes for the reflected signal (or echo) to be received by the sensor.
Dr. Josef Binder, one of the developers of the technology, says that while due to an extremely high DAQ rate the positioning accuracy of the system is about 2X better than magnetostrictive and 10X better than potentiometer sensors, the real power of the technology lies in its ability to provide a host of diagnostic information. That's because the high-energy echo also picks up harmonics created by any vibration, off-axis motion, friction, signal degradation, and other indicators of looming maintenance issues.
Because the sensor is fully encapsulated within the cylinder, Festo is initially targeting applications involving strong magnetic field environments and washdown requirements. The technology is available on cylinders up to 150 mm in diameter. For more information e-mail haugafesto.com.