Lub tsev yog ib txoj hauj lwm nyuaj. Nws yuav tsum tau siv lub tshuab hnyav los khawb, thauj thiab tsim. Architects, cov neeg cog lus thiab engineers xav tau cov cuab yeej muaj zog uas tuaj yeem tiv taus cov xwm txheej hnyav thiab xa cov txiaj ntsig tshwj xeeb. Ib qho ntawm cov ntsiab lus tseem ceeb ntawm kev lag luam no yog taug qab undercarriage. Qhov no yog qhov thib ob feem ntau siv kev taug kev tom qab lub log tsheb hauv kev tsim kho tshuab. Yog hais tias koj tab tom nrhiav rau ib tug txhim khu kev qha crawler iav rau koj cov khoom siv mobile, koj muaj hmoo. Qhia txog lub xov tooj ntawm tes crawler undercarriage - qhov kev daws teeb meem zoo tshaj plaws rau koj lub xov tooj ntawm tes crushing thiab tshuaj ntsuam xav tau.