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\begin{align}
&PE = m_{Arm}glarm} g l_{Armarm} sin(\pi-\theta_Arm)
\\
&d_1sin(\theta_3)-L_2sin(\theta_2) - h_1 = 0{arm}) + m_{lid} g l_{lid} sin(\pi-\theta_{lid}) + \frac{1}{2} k \Delta_{\theta_{arm}}
\\
&KE = \frac{1}{2}I_{arm}\omega_{arm}^2 + \frac{1}{2}m_{coin}v_{coin}^2 + \frac{1}{2}I_{gear_1}\omega_{gear_1}^2 + \frac{1}{2}I_{gear_2}\omega_{gear_2}^2 + \frac{1}{2}*I_{lid}\omega_{arm}^2;
\end{align}