Ulungelelwaniso oluthathu, olukwabizwa ngokuba yi-dimension, ngumatshini wokulinganisa ukuchaneka, obizwa ngokuba yiCMM.Sisixhobo sokulinganisa esichanekileyo esaphuhliswa ngeminyaka yoo-1960.Kwavela ngenxa yobuchule obuphezulu bezixhobo zoomatshini abazenzekelayo kunye nezixhobo zoomatshini be-CNC, kunye nesidingo sezixhobo zokulinganisa ezikhawulezayo nezithembekileyo zokusetyenzwa kwamacandelo anzima ngakumbi nangakumbi.

Okwangoku, umlinganiselo wolungelelwaniso oluthathu usetyenziswe ngokubanzi kumashishini ahlukeneyo afana nokuvelisa oomatshini, ishishini leemoto, ishishini lombane, ishishini le-aerospace, njl.Kwiigeji zethu ezikhethekileyo ezingekho mgangathweni, umlinganiso wolungelelwaniso oluthathu sisixhobo sovavanyo esiyimfuneko.Emva kokuba sifumene imizobo yemveliso yomthengi kunye nokuyila isicwangciso segage esihlangabezana neemfuno ezifanelekileyo zemveliso kwaye umthengi wanelisekile, kuyimfuneko.Qala amanyathelo okucubungula kwisigaba samva, ngoko kufuneka sisebenzise umlinganiselo wethu wokulungelelanisa ezintathu, kuba ukuchaneka kwesixhobo ngokwawo kuphezulu kakhulu, ngoko sisebenzise ukuvavanya ukuchaneka kwendawo nganye yegeji yethu, i-gage ngokwayo ngakumbi. iqinisekisa ukuchaneka kwezixhobo zethu zokuhlola.Ngokomzekelo, indawo ethile ye-gage, i-flatness kunye neprofayili yakhe ibandakanya ezinye iindawo zemoto.Sonke sinokufumana ubungakanani bokwenene ngokubona umlinganiselo wolungelelwaniso