Unit 2, section 2.1.4

Course Support Basic Arm Kinematics
1

Hello!
Why angle here is taken theta/2? image attached

rotation
rotation822×119 17 KB

2

Hi,

This is due to the fact that we are converting from euler to quaternions. Have a look at this source: Maths - Conversion Euler to Quaternion - Martin Baker

But the basic idea is that we have euler angles and using quaterions, the conversion is done that way.

3

Thanks for sharing link.