The Trabuco is a type of siege engine that was popular throughout the middle ages. Its two main uses involved either knocking down the walls of a castle, gate, or other building, or heaving projectiles over the top of them. It is similar to a catapult, except that it uses a counterweight to gain the energy and momentum to launch projectiles instead of relying on the tension in the launch device.
The Trabuco was a popular siege weapon throughout Europe and the Mediterranean for the entire medieval period as well as a portion of the Renaissance but found its beginnings during the Zhou dynasty in China around 400 BCE.
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Utilizing the transfer of potential into kinetic energy, the Trabuco consists of a stand with two pillars of points where a pole is attached to its center point along the Y-Axis. This is the fulcrum point at which energy transfer will occur. There is a counterweight attached to one end of the pole and a basket at the other. The basket is where the projectile will be housed. The height and weight of the counterweight will determine the size of the projectile and the distance it can travel. The counterweight is kept in place either by a pin or by ropes, and when it is let loose it will swing around the underside of the fulcrum launching the projectile into the air. Projectiles consisted of stone, dirt, and even decaying bodies.
Early forms of the Trabuco can be found in ancient Chinese versions of the sling that would use an extended piece of wood to have a better lever. As technology advanced the Trabuco eventually began making its way westward throughout the rest of the known world. It appears in the Muslim world as early as the twelfth century according to medieval Islamic scholars and may have actually been introduced to Salamin during his battles with the Christians during the Crusades according to youtube.com. Likewise, in the Christian world, the Trabuco first appears in the histories around the same time, though there are accounts of its use as early as the Viking siege on Angers in 873 CE.