Distributed motion control as an example of fast synchronised processes (see , , ) has been becoming more and more wide-spread because the possibilities of today’s communication systems regarding bandwidth and low jitter have improved significantly in recent years. With the communication cycles in the range of hundreds of microseconds there have been many applications to fulfil completely the requirements. Recently such solutions have appeared that allow transferring cyclic data over the network with cycle times in the range of tens of microseconds. However, the application requirements does not need to utilize such short cycle times currently.
The purpose of this work is to analyse systematically the application requirements for distributed motion control with respect to the local control loops on one hand, and the delay (see ) and jitter as a feature of the information flow to the central application. The entire path that corresponds to the delay and jitter will be described analytically or parametrically.
In the next phase the situation will be analysed with respect to short cycle times. The purpose will be to find out for what type of processes and under what control actions the short cycle times mean an advantage for the quality of control. The delay path is influenced not only by various delays in the device and during the data transfer but also by the placement of the messages in the network cycle. This dependency will be part of the analysis.