Options
2010
Conference Paper
Titel
Fault tolerant sequential control
Abstract
Due to an increasing number of functions and process steps modern mechatronic assembly lines become more and more complex. Especially high precision systems face the conflict between extended availability requirements and system complexity, bearing in mind the related economic pressure. Besides the increasing demands in productivity there are also raising demands in availability and reliability. Hence a systematic approach of manufacturing and assembly plants is necessary. To meet this challenge a consortium consisting of several different companies and Fraunhofer IWU has started the project VerMont. It is focused on an integrated concept to significantly improve the availability of complex units. The ambitious tasks were the increase of the MTBF (Mean Time Between Failure) and the reduction of the MTTR (Mean Time To Repair) by means of complementary interventions in the control and assistance level. To minimize the lifecycle costs five different approaches have been examined. One of them seems to be well suited and is presented in this paper. The so called fault tolerant sensor / time sequence control should work at the level of system control. The approach is that a fault sensor signal is tolerated as transition in the sequencer as long as there is no risk for the system, product or operator. The necessary repair operation can be postponed to the regular production breaks. The developed solution possesses to apply the approach at Assembly plants during the planning or even to expand existing plants to increase their availability.
Tags