Introduction

Photo: Compound

http://www.patentsencyclopedia.com/img/20110120436_14.png

Page: November 23rd, 2016 by Jacob Peeples

Energy and work are at the heart of physics. They too lie at the heart of archery. Archers do work to store potential energy in the bow which then they direct and release allowing it to be converted into kinetic energy in the arrow. When at full draw an archer must continue to exert force on the bow. Learning to manage this required force while maintaining proper form and aiming can be challenging to learn.

As stated earlier archery technology has come a long way. Modern equipment has found ways to reduce the amount of force required to do work on the bow and clever ways to store energy.

The compound bow has become popular for two reasons; efficiency and ease. Compound bows use pulleys to conserve work and total tension on the bow while reducing the force from the archer required to maintain the bow at full draw. This makes aiming and release easier to preform and preform well without sacrificing performance in the hunting or target sectors. In a limited sense the use of these "cams" increase the distance over which the string can be moved by swinging outward, and reduce the required pull by creating multiple tensions on the bow.

Figure: Static Force

http://margo.student.utwente.nl/sagi/artikel/bas/arch1.gif

This figure shows the relationship between draw length and force required to maintain static equilibrium at that draw length.Though the three bows in question all start and end in the same force, the effective draw weight for the compound is much greater but at full draw the force required is comparable to a lighter draw bow.