midieval catapault on a modern day tank chasis

There is even a claim that it was Philip II with his team of engineers who invented the ballista after improving Dionysius's device, which was merely an oversized slingshot. Historical accounts, for instance, cited that Philip II employed a group of engineers within his army to design and build catapults for his military campaigns. For all of the tactical advantages offered, it was only under Philip II of Macedon, and even more so under his son Alexander, that the ballista began to develop and gain recognition as both a siege engine and field artillery. Some were positioned inside large, armored, mobile siege towers or even on the edge of a battlefield. It would be assembled with local wood, if necessary. All components that were not made of wood were transported in the baggage train. The earliest form of the ballista is thought to have been developed for Dionysius of Syracuse, c. By contrast, the comparatively slow relaxation time of a tension machine such as the oxybeles meant that much less energy could be transferred to light projectiles, limiting the effective range of the weapon. Thus it was possible to shoot lighter projectiles with higher velocities over a longer distance. The advantage of this new technology was the fast relaxation time of this system. With the invention of torsion spring bundle technology, the first ballistae were built. It had a lower rate of fire and was used as a siege engine. The oxybeles were a bigger and heavier construction employing a winch and were mounted on a tripod.

This produced a weapon that, it was claimed, could be operated by a person of average strength but which had a power that allowed it to be successfully used against armored troops.

The operator would then walk forward to arm the weapon while a ratchet prevented it from shooting during loading. It had a composite prod and was spanned by bracing the front end of the weapon against the ground while placing the end of a slider mechanism against the stomach. The gastraphetes ('belly-bow') was a handheld crossbow.

The early ballistae in Ancient Greece were developed from two weapons called oxybeles and gastraphetes.

Midieval catapault on a modern day tank chasis