Guppy Grubhub

One fixed-speed DC motor drives everything: two Grashof four-bar legs riding alongside two wheels, synthesized in PKMS+ for close to 50% ground contact per cycle, and a six-compartment snack carousel indexed through a bevel gear. With no way to tune the motor, all speed and timing come from gearing. A 7.14 cm half-period stride from gait simulation set a ~42:1 reduction, split across a custom four-stage train (2.5 · 2.5 · 3 · 2.25). It crossed the 10 m course in about a minute, over twice the required speed, dispensing every 1.8–2 m.