指南车

Q: What did South-Pointing Chariot / Differential Gear Chariot look like?

A two-wheeled chariot with a wooden figure standing on top, arm extended forward. A complex gear mechanism is concealed within the body.

Q: How did South-Pointing Chariot / Differential Gear Chariot work?

When the left and right wheels turn at different rates, the differential gear train automatically computes the angular difference and drives the figure on top to rotate in the opposite direction by an equal angle.

South-Pointing Chariot / Differential Gear Chariot

A differential gear train that keeps a wooden figure on the chariot pointing south regardless of how the vehicle turns, without relying on magnetism. The world's earliest differential mechanism.

指南车

Scientific Principle

Differential gear principle: ω_output = (ω_left + ω_right)/2.

指南车

South-Pointing Chariot / Differential Gear Chariot

Scientific Principle

Related · 东汉