Taking　certain　type　of　CNC　camshaft　grinders　as　the　research　object,　through　the　analysis　of　its　structure　and　movement　to　determine　a　total　of　21　error　parameters,　a　model　describing　the　motion　relations　between　adjacent　body　coordinate　systems　containing　the　error　parameters　was　established.　The　machine　movements　were　classified　into　two　kinematic　chains:　the　＇bed-workpiece＇　and　＇bed-tool＇.　The　topological　structure　of　the　machine　tool　was　built　and　then　the　multi-body　system　theory　was　applied　to　model　the　errors　of　the　machine　tool.　Body　coordinate　systems　and　motion　reference　coordinate　systems　were　set　up　on　each　moving　body　and　the　corresponding　transformation　matrix　was　derived　by　joining　the　motion　relation　models　between　adjacent　body　coordinate　systems.　In　order　to　achieve　precision　machining　in　the　case　of　the　existence　of　influential　errors,　a　constraint　equation　Pw　=　Pt　was　put　forward　and　solved.　A　mathematical　model　of　the　X-C　axis　linkage　during　camshaft　grinding　was　proposed　to　work　out　the　grinding　point　coordinates　in　the　workpiece　coordinate　system　and　tool　coordinate　system.　Three　kinds　of　measurement　methods　were　provided　to　identify　15　error　parameters　affecting　the　camshaft　machining　by　using　a　cue　instrument,　which　provides　necessary　conditions　to　research　the　machine　tool　error　compensation.　©　Published　under　licence　by　IOP　Publishing　Ltd.