▁the ▁tool ▁is ▁used ▁in ▁order ▁to ▁make ▁it ▁naturally ▁v ibr ate ▁while ▁cutting ; ▁v ibr ations ▁are ▁self - m aint ained ▁by ▁a ▁mass - spring ▁system ▁included ▁in ▁the ▁tool ▁holder . ▁Other ▁works ▁use ▁a ▁pie zo elect ric ▁system ▁to ▁generate ▁and ▁control ▁the ▁v ibr ations . ▁These ▁systems ▁allow ▁high ▁v ibration ▁frequencies ▁( up ▁to ▁ 2   k Hz ) ▁for ▁small ▁magnitude ▁( about ▁a ▁few ▁mic rom eters ); ▁they ▁are ▁particularly ▁suitable ▁for ▁dr illing ▁small ▁holes . ▁Finally , ▁v ibr ations ▁can ▁be ▁generated ▁by ▁mechanical ▁systems : ▁the ▁frequency ▁is ▁given ▁by ▁the ▁combination ▁of ▁the ▁rotation ▁speed ▁and ▁the ▁number ▁of ▁oscill ation ▁per ▁rotation ▁( a ▁few ▁oscill ations ▁per ▁rotation ), ▁with ▁magnitude ▁about ▁ 0 . 1   mm . ▁ ▁This ▁last ▁technology ▁is ▁a ▁fully ▁industrial ▁one ▁( example : ▁S ine Hol ing ® ▁technology ▁of ▁M IT IS ). ▁V ibration ▁dr illing ▁is ▁a ▁preferred ▁solution ▁in ▁situations ▁like ▁deep ▁hole ▁dr illing , ▁multi - material ▁stack ▁dr illing ▁( a er onaut ics ) ▁and ▁dry ▁dr illing ▁( without ▁lub ric ation ). ▁Gener ally , ▁it ▁provides ▁improved ▁reli ability ▁and ▁greater ▁control ▁of ▁the ▁dr illing ▁operation . ▁ ▁Circle ▁interpol ating ▁▁ ▁Circle ▁interpol ating , ▁also ▁known ▁as ▁orb ital ▁dr illing , ▁is ▁a ▁process ▁for ▁creating ▁holes ▁using ▁machine ▁cut ters . ▁ ▁Or b ital ▁dr illing