Cov khoom siv hluav taws xob laum khoom siv hauv tsev neeg (xa mus rau DIY txawv teb chaws) muaj qis dua qhov xav tau ntawm kev ua neej, kev ua haujlwm thiab kev ua kom raug, thiab cov naj npawb ntawm cov khoom lag luam loj, suav txog 70 ~ 80% ntawm tag nrho cov khoom siv hluav taws xob laum; lwm 30 ~ 20% Cov khoom siv hluav taws xob yog cov cuab yeej tshaj lij, uas yog, cov khoom lag luam feem ntau hu ua "cov cuab yeej hluav taws xob muaj zog" hauv Suav, uas muaj cov txheej txheem kev ua haujlwm siab, suav nrog kev ua kom raug, kev ntseeg tau ntawm kev siv (xws li ib zaug tsis ua haujlwm, tus naj npawb ntawm kev puas tsuaj), kev pab cuam lub neej, thiab qib tau zoo. (xws li torque, coaxiality) thiab lwm yam yog li siab dua cov khoom vaj khoom tsev.
Lub tshuab ua kev rwb thaiv tsev ob npaug muab kev nyab xeeb, txhim khu kev ntseeg thiab kev ua kom tsis txhob txhawm rau tiv thaiv hluav taws xob kev sib tsoo rau kev siv cov cuab yeej hluav taws xob ua haujlwm, thiab yog kev hloov pauv ntawm kev txhim kho lub zog hluav taws xob kev ruaj ntseg thev naus laus zis. Txij li xyoo 1960, Tuam Tshoj lub zog tsim hluav taws xob kev lag luam pib kawm txog kev siv hluav taws xob ob npaug rau hauv cov cuab yeej hluav taws xob, thiab kev tiv thaiv kab hluav taws xob thiab lwm yam khoom lag luam. Xyoo 1998, ob npaug rau cov cuab yeej siv hluav taws xob ntxig tau ntau tshaj li 90% ntawm kev lag luam txhua xyoo.
