I need to specify the pose for a 5 dof robot arm in order to calculate the inverse kinematics. Assuming I worked out the correct inverse kinematics solution for joint variables $q_{1} \dots q_{5}$, I now want to specify a (4x4) homogeneous transformation matrix from which get 3 position coordinates of the EE and the angle $\phi$ of $z_{5}$ from horizontal plane $x_{0}-y_{0}$ to use them for inverse kinematics. The kinematic scheme is the following:
I don't really care about the orientation $\phi = q_{2}+q_{3}+q_{4}$ but I I need to specify it because of the form of the IK equations. I'm using Peter Corke Matlab Robotics Toolbox. Please give me some help, thank you
Edit: picture showing angle $\phi$
If I choose three coordinates x,y,z that the robot can reach, I'd like to reach that position without caring about orientation $\phi$. For one point maybe $\phi$ can be computed, but for a trajectory?