Harmonic Drive Reduction
Compute the reduction ratio of a harmonic drive (strain wave gear), R = Nf/(Nc − Nf), where Nf is the flexspline tooth count and Nc the circular spline's (usually Nc = Nf + 2). This ingenious mechanism reaches huge reductions (50:1 to 300:1) in a single compact stage with zero backlash — which is why it is the heart of industrial and collaborative robot joints. Enter the flexspline and circular spline tooth counts.
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Redução de harmonic drive
O harmonic drive (ou redutor de onda de tensão) é uma das engenhocas mais elegantes da robótica. Tem três peças: um gerador de onda elíptico, um copo flexível dentado (flexspline, Nf dentes) e um anel rígido (circular spline, Nc dentes, geralmente Nf+2). A elipse força o flexspline a engrenar com o anel em dois pontos opostos; a cada volta do gerador, o flexspline 'atrasa' apenas a diferença de dentes. A redução enorme sai de R = Nf/(Nc − Nf): com Nf=200 e Nc=202, R = 100:1 num único estágio compacto! E o melhor: praticamente sem folga (zero backlash), o que dá precisão de posicionamento. Por isso domina as juntas de robôs industriais e colaborativos. Informe o número de dentes do flexspline e do circular spline.
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