For　kinematically　redundant　robots,　the　optimal　relative　locations　between　tasks　and　robots　could　be　determined　by　optimization　methods.　Due　to　redundancy,　the　practical　performance　evaluation　of　points　in　the　workspace　is　hard　to　be　determined.　For　analyzing　the　properties　of　redundant　robots　in　a　global　view,　the　concept　of　performance　manifolds　is　introduced.　Furthermore,　given　an　arbitrary　performance　index,　the　method　to　identify　all　the　corresponding　performance　manifolds　in　the　configuration　space　is　proposed.　Finally,　based　on　performance　manifolds,　a　motion　planning　method　is　developed　to　identify　the　task　location　and　a　smooth　joint　trajectory　following　this　task,　meanwhile　satisfying　the　desired　performance.　Simulation　studies　on　a　KUKA　LBR　iiwa　robot　verify　the　effectiveness　of　the　proposed　methods.　©　2020　ACM.