Tsarin jiki na makina ita ce "karkara" da "shell" na makina. Taba tashin makina, kima'anta cikin makina, kuma kima'anta jiki na makina. Wannan tsari yake amincewa a lokacin amfani, ko idan ke kaddamar da safiya ko kaddamarwa alhakin safiya, tsarin jiki yake amincewa role mai muhimmanci.