e(toolpath)toachievethemaximummanufacturingefficiency.Theantcolonyoptimization(ACO)algorithmsareemployedinsearchingtheoptimaltoolpath.SensitivitiesofcontrolparametersofACOarealsoanalysed.Throughapplications,theproposedmethodcansignificantlyimprovetheoperationefficiencyforthecombinedpunch-and-lasermachine.ThemethodcanalsobeeasilyautomatedandintegratedwiththenestingandG-codegenerationprocesses.Someissuesandpossiblefutureresearchtopicshavealsobeendiscussed.Keywords:Combinationmachine;Combinedpunch-and-lasermachine;Sheetmetal;Processplanning;Optimization;Antcolonyoptimization.IntroductionModerncomputernumericcontrolled(CNC)turretpunchesrepresenthighlyversatilemachinetoolscapableofproducingsheetmetalandplasticcomponentsquicklyandaccurately.However,theversatilityofsuchturretpunchesislimitedinthatmaterialcanberemovedfromtheworkpieceonlybyapunchingtypeoperation.Whenlargeareasoftheworkpiecearetoberemoved,orwhentheworkpiece