I still need help to convert another system to that form, but this one has four input (u1 ... u4). m1, m2 and m3 are scalar. The dynamic system is:

xddot = u1

yddot = (m1/m2)*tan(psi)*u1

zddot = (-m1/m3)*tan(theta)*sec(psi)*u1

phiddot = u2

thetaddot = u3

psiddot = u4

Following Ackbeet's method in my other thread, and got like this pattern:

y1ddot = v1

y2ddot= v4

y3ddot = v3

y4ddot = v2

y5ddot = (m1/m2)y2v1

y6ddot = (-m1/m3)(1/sin(psi)) y2y3v1

May be the final solution can be simplify to be more close to the new form pattern, because in my calculation still has like sin(psi) in y6ddot. I want to check it with Ackbeet's calculation.

Thank you very much.