How does physics of collar and breast collar actually work?
The following illustrations will help to explain it. Let’s use a collar first and see, what happens: G is the centre of gravity of the horse and D1 and D2 are the ideal points of draft of a collar. Their position is depending on the different centres of resistance, W1 and W2. Looking at this graphic it is easy to understand that a horse can pull best from a point of draft just in front of its shoulder joints. This point is found to be in line with its gravity centre and the drawn vehicle’s or object’s centre of resistance. In case of an object on the ground, e.g. a timberlog, the ideal pulling point is located at D1 in front of the shoulderjoint. It is in line with the gravity G and the timberlog’s centre of resistance, W1. If the horse pulls a vehicle with a higher-up located centre of resistance W2, the ideal point of draft D2 moves a bit down, towards the point of the shoulder.
