Picture 1 shows a demonstration that rotations around an axis is positive for clockwise directions.
An example later on, picture 2, applies a rotation matrix for 60 degrees in the x-axis for a clockwise rotation.
In the first line of working in picture 2, where
Rx(-60) = x_rotation_matrix
Am I correct in thinking that the argument for the rotation matrix in the x-axis should be 60 degrees, and not -60 degrees? Additionally, should the argument for the rotation matrix in the y-axis
Ry(30) = y_rotation_matrix
be -30 degrees, and not 30 degrees?
Thanks.
Best Answer
Roughly,It doesn't matter which direction you choose positive.you can choose positive in any direction you wish,but you must have to conduct your all calculations by reminding that in mind.Don't use CW positive in one part of the calculation and CCW positive in another part. just follow one of them in your full calculation.
But there are some conventional ways for these assumptions.But they vary according to their application.Like,in kinematics generally the convention is "CCW is positive",but When we work on flux measurement in electrical machines like in motor or generator,then it is varied from motor to generator.