Networked sensing architecture using oversampling techniques in PROFINET IRT devices and isochronous mode processing: Proof-of-principle and signal reconstruction at IO Controller side

The revamping of a machine manufacturer's line of high speed processing machines aims to reuse existing validated STEP 7 code. The distributed networked sensing architecture is required to pick out a single analog measurement with 50 ps resolution at specific encoder sample hits, using off-the-shelf PROFINET I/O. A solution using an oversampling technique on a remote I/O device combined with a low-cost “streaming CPU” running in isochronous processing mode and acting as sync master in PROFINET IRT is proposed. The distributed architecture connects a main CPU to the streaming CPU, the latter configured as I-Device in a 2
^nd
PROFINET RT network. Overall distributed architecture, accurate reconstruction of the signal timing, network load and the signal propagation are analysed.