6 : 1 · quasi-direct-drive actuator

The low-ratio stage legged robots put behind a brushless motor; flanged ring, six M3 bolts.

Robot joints & actuators6 : 13 planetsRing held

Build it with your AI

Using the CheapCADTools connector, design a 6 : 1 planetary gear set in Planetary Gear Designer: module 1 mm, 20° pressure angle, herringbone teeth, a 16-tooth sun, 32-tooth planets and an 80-tooth ring, three planets, a profile shift of 0.1 on the sun, face width 12 mm. The sun: an 8 mm bore. The carrier's output: an 8 mm bore. The ring: six M3 bolt holes, an 8.5 mm rim below the roots. Check the design, apply any Auto-fix it suggests, then export every part (the sun, a planet, the ring and the carrier) as STEP and STL and give me the download link.

Paste it into Claude, ChatGPT or any AI app with the CheapCADTools connector, and it designs this planetary set with you, checks it and hands you the files. How to connect your AI.

What's in this design

Sun

16 teeth · shift +0.1 · tip Ø18.76 mm · face 12 mm · bore Ø8 mm · no hub

Planets · 3

32 teeth · no shift · tip Ø35.13 mm · face 12 mm · bore Ø5.3 mm on a Ø5 mm pin · print 3

Ring

80 internal teeth · shift −0.1 · outside Ø102.8 mm · rim 8.5 mm below the roots · 6 × M3 bolt holes Ø3.4 mm on Ø94.3 mm

Carrier

straddle (two discs and posts) · disc Ø80.02 × 5 mm · 3 pins Ø5 × 23.0 mm · output bore Ø8 mm

The set · Module 1 · 20° · herringbone

6 : 1 reduction: the ring is held, the sun is the input and the carrier the output.

Notes

Hardware: 3 × planet pin Ø5 × 23.0 mm; 3 × M3 screw, about 11 mm long; 6 × M3 bolt through the ring.
The Strength check rates spur sets only: helical and herringbone sets aren't rated yet.

The link opens the whole set in the Planetary Gear Designer's 3D view. Change the teeth, the number of planets or stages, which member is held, the carrier, bores or hubs, then download STL, STEP or the carrier's DXF and SVG.

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