Extension of the Quay Crane Scheduling Problem for a scheduling of several rail-mounted robots and the development of a heuristic solver for fiber placement processes

Abstract

The automation of manufacturing large scale Carbon Fibre Reinforced Plastic (CFRP) components is still a relevant topic in research. It is necessary to speed up and improve production due to the increased demand for CFRP components. In the course of the project GroFi the German Aerospace Center (DLR) built a production plant for the fully automated manufacturing of large scale CFRP components for aerospace applications. It is lo-cated at the DLR site Center for Lightweight-Production-Technology in Stade. One of the key features of the facility is the possibility of simultaneously producing CFRP components with multiple, mobile, rail-mounted robots. What is anticipated is that this concept will drastically increase the speed of the production process and, through the use of redundancies, reduce downtimes of the facility. In addition to the generation of Numerical Code for robots this introduces the need for scheduling their tasks. Scheduling on limited space with limited flexibility is prone to error when done manually. Therefore and according to the paradigm of current strategy Industry 4.0 an automated method is being developed. This presentation deals with the modelling of and a heuristic solution to this production process. In general both can be applied to processes of several robot units which are mobile on a single rail. The production process was formulated as a Mixed Integer Problem by using analogies to the Quay Crane Scheduling Problem. Furthermore, a genetic algorithm was developed and implemented as a heuristic solver.