Optimal Design of a Reconfigurable Machine Tool Considering Machine Configurations and Configuration Changes

A reconfigurable machine tool (RMT) is used as a group of machines by changing its configurations for different machining functions such as milling and turning. An optimization approach is introduced in this research for the design of a RMT based on evaluations to both the different machine configurations and the reconfiguration processes to change between machine configurations. In this research, different design candidates, machine configurations for each design candidate, and parameters of the machine configurations are modeled by a generic design AND-OR tree based on design requirements. A specific design solution modeled by multiple machine configurations and their parameters is created from the generic design AND-OR tree by tree-based search. For each design solution, reconfiguration process to change from one machine configuration to another configuration is modeled by a generic process AND-OR graph that is composed of operation candidates, sequential constraints among operations and operation parameters. A specific process solution is created from the generic process AND-OR graph by graph-based search. A multi-level and multi-objective optimization method is developed to obtain the optimal design that is modeled by its machine configurations, parameters of machine configurations, reconfiguration processes to change between machine configurations, and parameters of reconfiguration processes. A case study is implemented to demonstrate the effectiveness of this new optimal RMT design approach.