A Service-Orientated Arhitecture for Holonic Manufacturing Control

The paper describes a solution and implementing framework for the management of changes which may occur in a holonic manufacturing system. This solution is part of the semi-heterarchical control architecture developed for agile job shop assembly with intelligent robots-vision workstations. Two categories of changes in the manufacturing system are considered: (i) changes occurring in resource status at process level: breakdown, failure of (vision-based) in-line inspection operation, and depletion of local robot storages; (ii) changes in production orders at business (ERP) level: rush orders. All these situations trigger production plan update and rescheduling (they redefine the list of Order Holons) by pipelining CNP-type resource bidding at shop-floor horizon with global product scheduling at aggregate batch horizon. Failure- and recovery management are developed as generic scenarios embedding the CNP mechanism into production selfrescheduling. Implementing solutions and experimental results are reported for a 6-station robot-vision assembly cell with twin-track closed-loop pallet transportation system, Cartesian pallet feeding station, dual assembly component feeder with robot-vision tending and product tracking RD/WR devices. Future developments will consider manufacturing integration at enterprise level.