Joint where frame_a rotates around axis nx which is fixed in frame_a and at the same time rotates around axis ny which is fixed in frame_b. The relative angles revolute1.q, revolute2.q [rad] and the relative angular velocities revolute1.qd, revolute2.qd [rad/s] are used as state variables.
The following parameters are used to define the joint:
nx : Axis of rotation 1 resolved in frame_a.
nx must not necessarily be a unit vector. E.g.,
nx = {0, 0, 1} or nx = {1, 0, 1}
ny : Axis of rotation 2 resolved in frame_b.
ny must not necessarily be a unit vector. E.g.,
ny = {0, 0, 1} or ny = {1, 0, 1}
qx0: Rotation angle offset 1 in [deg].
qy0: Rotation angle offset 2 in [deg].
If revolute1.q=qx0 and revolute2.q=qy0,
frame_a and frame_b are identical.
startValueFixed: true, if start values of q, qd are fixed.