[{"data":1,"prerenderedAt":99},["ShallowReactive",2],{"\u002Fen\u002Fglossary\u002Fplanetary-gearbox":3},{"id":4,"title":5,"alternateName":6,"body":7,"description":89,"extension":90,"keywords":91,"meta":92,"navigation":93,"path":94,"seo":95,"stem":96,"updated":97,"__hash__":98},"glossary\u002Fglossary\u002Fen\u002Fplanetary-gearbox.md","Planetary Gearbox","行星减速器",{"type":8,"value":9,"toc":83},"minimark",[10,15,24,29,68,72,75],[11,12,14],"h1",{"id":13},"what-is-a-planetary-gearbox","What Is a Planetary Gearbox?",[16,17,18,19,23],"p",{},"A ",[20,21,22],"strong",{},"planetary gearbox"," is a gear train built from a central sun gear (input), several planet gears, and an outer ring gear. The planets spin on their own axes while orbiting the sun — like planets around a star, hence the name. It converts a motor's high speed into low-speed, high-torque output.",[25,26,28],"h2",{"id":27},"structural-advantages","Structural Advantages",[30,31,32,39,51,57],"ul",{},[33,34,35,38],"li",{},[20,36,37],{},"Load sharing",": torque is split across multiple planet gears, giving high torque density and impact tolerance.",[33,40,41,44,45,50],{},[20,42,43],{},"Coaxial input\u002Foutput",": the compact cylindrical form factor suits integrated ",[46,47,49],"a",{"href":48},"\u002Fen\u002Fglossary\u002Fjoint-motor","joint motors"," naturally.",[33,52,53,56],{},[20,54,55],{},"High efficiency",": single-stage efficiency typically exceeds 95%, higher than harmonic drives.",[33,58,59,62,63,67],{},[20,60,61],{},"Hollow-friendly",": a through-bore at the center enables ",[46,64,66],{"href":65},"\u002Fen\u002Fglossary\u002Fhollow-shaft-motor","hollow-shaft cable routing",".",[25,69,71],{"id":70},"planetary-vs-harmonic","Planetary vs. Harmonic",[16,73,74],{},"Harmonic drives offer large ratios (50–160) and zero backlash but lower efficiency, limited stiffness, and higher cost. Planetary gearboxes have smaller ratios (roughly 3–10 per stage, ~20 with compounding) and slight backlash, but win on efficiency, shock tolerance, and cost — decisive advantages for high-dynamic humanoid leg joints.",[16,76,77,78,82],{},"The BXI ",[46,79,81],{"href":80},"\u002Fen\u002Fmotors\u002Fadvanced-motors","85\u002F70\u002F50-series joint motors"," all use a 19.5-ratio planetary design with a uniform 100 rpm rated output speed, so sizing reduces to picking the right torque tier.",{"title":84,"searchDepth":85,"depth":85,"links":86},"",2,[87,88],{"id":27,"depth":85,"text":28},{"id":70,"depth":85,"text":71},"A planetary gearbox uses a sun gear, planet gears, and a ring gear with multiple simultaneous tooth contacts and coaxial input\u002Foutput — delivering high torque density, compactness, and efficiency for robot joint motors.","md","planetary gearbox, planetary reducer, reduction ratio, robot gearbox, harmonic drive comparison",{},true,"\u002Fglossary\u002Fen\u002Fplanetary-gearbox",{"title":5,"description":89},"glossary\u002Fen\u002Fplanetary-gearbox",null,"MMMfDWhs9jXejonqa7muAjm4xvqSAKEEFnKVsAI7_GE",1783425867297]