Qhov tseeb, nws yog siv dav heev: Qhov tseeb, yog dav siv: lub cev muaj zog hlau nplaum ruaj khov, sib nqus crane, sib nqus chuck, sib nqus actuator (synchronous kis, hysteresis, eddy tam sim no tsav), sib nqus caij nplooj ntoos hlav (Lub nkhaus yog opposite rau lub caij nplooj ntoos hlav duab. thaum lawv nyiam), kev ruaj ntseg sen...
Nyeem ntxiv