# Gearbox arrangement and envelope
# Scope: Two external spur outside circles plus supplied housing clearance.
# Status: illustrative worked example; engineering review pending.
# Inputs are example values. Checks are editable example requirements, not standards.

module = 2 mm
teethA = 20
teethB = 40
clearance = 5 mm

center := module*(teethA+teethB)/2 [mm]
length := center+module*(teethA+teethB+4)/2+2*clearance [mm]
height := module*(max(teethA,teethB)+2)+2*clearance [mm]

check housing length budget: length <= 150 mm

scenario alternative: module = 1.6 mm