Learning Forum

[peteroznewman]

nAssume that we want to find the angle between two vectors:na = [3, 6, 1]nand b defined asnthe vector between point A = (1, 1, 2) and B = (-4, -8, 6).nWhat do we need to do?nFirst, calculate vector b, given the initial and terminal points:nb = [-4 - 1, -8 - 1, 6 - 2] = [-5, -9, 4]nThen, find the dot product of vectors a and b:na ? b = (3 * -5) + (6 * -9) + (1 * 6) = -15 - 54 + 6 = -65nNext, determine the magnitude of vectors:n|a| = v(3? + 6? + 1?) = v46 ? 6.782n|b| = v(-5? + -9? + 4?) = v122 ? 11.045nFinally, use the transformed dot product equation:na = arccos[(a ? b) / (|a| * |b|)] = arccos[-65 / (6.782 * 11.045)] = arccos(-0.86767) = 150.189 ? 150.2?nAnd there you go! You've just calculated the angle between two 3D vectors. nIs your question how to get the coordinates of point A before the simulation and point B after the simulation?nIf Point A is a geometry vertex on the model, you can get the coordinates in Mechanical by selecting the Point filter and clicking on the vertex. The coordinates will be on the bottom edge of the window. Next you can put three Directional Deformations one for X, Y and Z and scope each to that vertex. Now you will have the vector components of the vector b. If you want to create the coordinates of the point B, you have to add the vector components of b to the coordinates of Point A.n