Hello,,,
Thanks you for your time.
Now, I am trying build Quadcopter Attitude + Z channel simulation with Linear Dynamics model on the Simulink of Matlab.
it's meaning, 4 outputs, namely, Phi Theta Psi and Z(Height) are exsist.
and I'm using PID controller block that Matlab provide.
also, I am using following linear equations.
phi_2dot = 1/Jx (Phi_2dot is meaning, Angular Acceleration. therefore, Phi_dot is Angular Velocity, Phi is Angle)
theta_2dot = 1/Jy
psi_2dot = 1/Jz
and
z_2dot = g - 1/m (z_2dot is Linear Acceleration and z_dot is Linear Velocity of Vertical, and z is Position z)
where, Jx, Jy, Jz is moments of inertia and m is mass of quadcopter.
but, problem is z channel.
always output is totally unstable and has strange graph.
the whole loop is in attached .pdf file. and output graph of z also attached in this post.
someone Could you give some advise ?
Please, let me know !!