图上涤支大峰 Double-rocker .Double-rocker >Input rocker:Limited rotation >Output link:Limited rotation e Q Steering mechanism Crane 周 上海充通大学 Two links:length is equal position is parallel 77777777 Coupler: horizontal motion ABCD BC ZAD Lift car Train wheel 66 Steering mechanism Double-rocker Crane A B D C E •Double-rocker Input rocker: Limited rotation Output link: Limited rotation Train wheel AB = CD BC = AD Lift car Two links: length is equal position is parallel Coupler: horizontal motion