Korthos educational rotary actuator model — 3 October 2026



actuator-model.js generates original procedural illustration geometry created for Korthos. No third-party CAD, meshes, textures or brand marks are incorporated. Korthos may use, modify and redistribute this generated model and viewer commercially without a third-party model fee. This notice does not license the rest of the website to others.



Three.js and OrbitControls are separately provided under the MIT licence; retain vendor/LICENSE.txt when redistributing those dependencies.



Scope: simplified brushless inrunner motor, single-stage fixed-ring planetary transmission, carrier/output flange, bearing, encoder, controller and housing. The illustrative 18/18/54 tooth counts give 4:1 ideal reduction. Teeth are simplified trapezoidal display profiles, not manufacturing involutes. No tolerances, electromagnetic design, validated thermal paths, sealing, fatigue, collision or structural analysis. Parts are separated axially in exploded view even when radially nested in the assembly.



General architecture references (not model sources):

https://global.maxongroup.com/high-efficiency-joints

https://github.com/bbokser/sprydrive

Do not describe this as any named vendor's actuator or as engineering-ready CAD.

2026-10-07 mechanism illustrations

strain-wave-model.js and magnetic-encoder-model.js contain original procedural Korthos illustrations. No manufacturer meshes, PCB layouts or semiconductor die geometry are incorporated. The existing SpryDrive encoder CAD remains a separate, attributed reference with its original MIT notice.

The strain-wave illustration has a fixed 102-tooth ring, a 100-tooth flexspline, an elliptical cam, thin-raced bearing and output flange. The ideal output/input ratio is -1/50. Tooth profiles, deformation, bearing-element motion, mounting holes and engagement markers are explanatory approximations, not validated contact geometry or manufacturing specifications.

The encoder illustration shows the principle of a diametric magnet rotating above a stationary Hall sensor. Its ideal 14-bit code uses 16,384 equal positions per turn and a zero offset. The package internals, PCB, connections and enlarged spacing are illustrative. Resolution is not an accuracy prediction. The model does not simulate magnetic flux, noise, temperature effects or calibration.

Technical references (not geometry sources):
https://www.harmonicdrive.net/technology/harmonicdrive
https://www.infineon.com/part/AS5048A


2026-10-03 additions: component-models.js provides a motor-only view of the original geometry. reference-hand.js provides original procedural palm, finger and thumb geometry with illustrative linked articulation. These are freely usable by Korthos; no external meshes are incorporated. When included in the Asimov-derived humanoid study, the combined model and modifications follow the CERN-OHL-S-2.0 terms stated in model/NOTICE.txt.