Sequences of rotations¶
A minimal parameterization of orientation can be obtained by using a set of three angles \(\{\alpha, \beta, \gamma\}\) together with an admissible composition sequence. A sequence of rotations is considered to be "admissible" if no two successive rotations are made around parallel axes. For example, Figure 1 depicts three successive rotations around the \(x \to y \to z\) axes of a fixed frame \(\Sigma_0\) (all at angles \(\pi/2\))
- \(R_x(\pi/2)\)
- \(R_y(\pi/2)R_x(\pi/2)\)
- \(R_z(\pi/2)R_y(\pi/2)R_x(\pi/2)\)
- \(R_z(\pi/2)\)
- \(R_z(\pi/2)R_y(\pi/2)\)
- \(R_z(\pi/2)R_y(\pi/2)R_x(\pi/2)\)