# Four-bar linkage
# Scope: Four-bar Grashof length criterion; no assembly-branch solve.
# Status: illustrative worked example; engineering review pending.
# Inputs are example values. Checks are editable example requirements, not standards.

shortest = 20 mm
longest = 60 mm
middleA = 40 mm
middleB = 50 mm

grashofMargin := middleA+middleB-shortest-longest [mm]

check Grashof length condition: grashofMargin >= 0 mm

scenario alternative: shortest = 16 mm