Military Technology
Doppler Radar
Doppler radar is a specialized radar system that uses the Doppler effect to measure the velocity of objects in addition to their position and distance. Widely employed in meteorology, aviation, and law enforcement, it can detect the speed and direction of moving targets such as precipitation, aircraft, and vehicles by analyzing frequency shifts in reflected radio waves.
Trebuchet
The trebuchet is a gravity- or manpower-powered medieval siege engine that uses a long lever and sling to hurl projectiles. Originating in China and spreading across Eurasia by late antiquity, it became the dominant artillery for breaching fortifications in the Middle Ages until superseded by gunpowder cannon. Its mechanics and historical use have been documented by historians and engineers, with modern reconstructions illuminating its range, payload, and efficiency.