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$$ \left( J_A + J_M / (N_r^2) \right) \ddot{\alpha}(t) = C_{asta}(t) - C_{peso}(t) + C_{mol}(t) + C_{fermo}(t) $$

$l(t) = \sqrt{h^2 + q^2 + b^2 - 2 b \left( - h \sin(\beta(t) / 180*\pi) + q \cos(\beta(t) / 180*\pi) \right)}$,

$F_m(t) = F_0 + K \left( l(t) - l_0 \right)$,

$
C_{fermo}(t) = \begin{cases}
  - \exp( (\alpha(t) - \pi/2) * K_f ) \text{ if } \alpha(t) > \pi/2 \\
  \exp( (0.0 - \alpha(t)) * K_f ) \text{ if } \alpha(t) < 0.0 \\
  0.0 \text{ otherwise }
\end{cases}
$

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