Centre of Pressure of 6 Degree of Freedom Loads, Applied to Impact Measurements on a Propeller Blade
Load measurements on various structures and objects arenowadays common in technical industries and research fields.The same applies to numerical computations where fluid forcesare integrated over surfaces to come to resultant forces andmoments. When forces and moments on a rigid body in 3D areconsidered, the total load is a 6 degree of freedom system.These are often denoted as the force in x-, y- and z-directionand the moments around the x-, y- and z-axis. A question thatoften arises in case of these 6 degree of freedom loads, is to findthe position of the centre of pressure. This is the position withzero resulting moment when the loads are translated to it. In 2Dthis is straightforward. However for 3D systems there is nostraightforward solution. Extending the mathematics from 2D to3D one might find a system of equations with a determinant thatis zero. Which means there is no solution or there are an infinitenumber of solutions.