Tension devices: mathematical modeling and applications in water transport

Abstract

Tension devices -are throwing devices, the action of which is based on the elastic tension of the plates (shoulders), in fact, these are bows and crossbows. Currently, various types of bows and crossbows controlled by a single shooter are widely used in hunting and sports. In the ancient World, high-power crossbows were used as artillery, served by several warriors: ballistae, scorpions and others. In the paper, bows and crossbows of all currently common types are modeled using mathematical methods. This model, which is the subject of this paper, differs from similar ones, which actually model only traditional English bows. All these models have the main purpose of analytical calculation of the speed of the arrow at the moment of its separation from the bowstring. Our model uses the law of conservation of energy, considering only the initial and final moments of acceleration of the arrow. It identifies 2-4 implicit indicators that fully describe each type of tension devices. To obtain input data, 2-3 experimental shots are made with 1-2 parameters measured each time. As a result, the calculations are reduced to solving systems of linear equations and to calculations using formulas. The paper offers 3 areas of application of tension devices on water transport, firstly, ship management and its operational repair (for this purpose, analogues of ancient powerful crossbows are relevant), secondly, protection of the ship, cargo, anti-terrorism, and thirdly, physical education and sports for the crew and passengers. The use is due to their fire safety, power, low noise, a variety of types of projectiles.