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\begin{eqnarry}
F_{z2} &=\dfrac{1}{2l}\left[\frac{1}{2}\rho S C_{x}h_{2}(\dfrac{\eta_{C}\eta_{d}}{\tau_{c}\tau_{d}})^{2}\omega_{e}^{2}+(m_{v}h_{1}R_{r}+4J_{w})\dfrac{\eta_{C}\eta_{d}}{\tau_{c}\tau_{d}}\dot{\omega}_{e}+m_{v}g(h_{1}i+l_{1}+U)\right]\\
F_{z1} &=-\dfrac{1}{2l}\left[\frac{1}{2}\rho S C_{x}h_{2}(\dfrac{\eta_{C}\eta_{d}}{\tau_{c}\tau_{d}})^{2}\omega_{e}^{2}+(m_{v}h_{1}R_{r}+4J_{w})\dfrac{\eta_{C}\eta_{d}}{\tau_{c}\tau_{d}}\dot{\omega}_{e}+m_{v}g(h_{1}i-l_{2}+U)\right]\\
F_{x1} &=-\dfrac{1}{2l}\left[\frac{1}{2}\rho S C_{x}h_{2}(\dfrac{\eta_{C}\eta_{d}}{\tau_{c}\tau_{d}})^{2}\omega_{e}^{2}+(m_{v}h_{1}R_{r}+(\frac{l}{R_{r}}+2)2J_{w})\dfrac{\eta_{C}\eta_{d}}{\tau_{c}\tau_{d}}\dot{\omega}_{e}\\
& +m_{v}g(h_{1}i-l_{2}+U)+2lf_{r}\right]\\
F_{x2} &=-\dfrac{1}{2l}\left[(\frac{h_2}{2}\frac{l}{2})\rho S C_{x}h_{2}(\dfrac{\eta_{C}\eta_{d}}{\tau_{c}\tau_{d}})^{2}\omega_{e}^{2}+(m_{v}R_{r}(h_{1}-l)+(\frac{l}{R_{r}}+2)2J_{w})\dfrac{\eta_{C}\eta_{d}}{\tau_{c}\tau_{d}}\dot{\omega}_{e}\\
& +m_{v}g((h_{1}-l)i-l_{2}+U)+2lf_{r}\right]\\
\end{eqnarry}



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