Screw Drive Loads and Torques

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F_{fr}=P\sin\theta \Leftrightarrow \mu N=P\sin\theta \mu (P\cos\theta)=P\sin\theta \Leftrightarrow \mu =\tan\theta \nu_{l} = n\frac{p}{60} =\left(\frac{rev}{min}\right)\left(\frac{m}{rev}\right)\left(\frac{min}{60s}\right) J_{S} = TBD, J_{M} = TBD J_{L} = \left(\frac{m_{LS}}{\eta}\left)\left(\frac{p^2}{4\pi^2}\right) T_{a} = J_{T}\Delta n = (J_{S}+J_{M}+J_{L})\left(\frac{2\pi}{rev}\right)\left(\frac{min}{60s}\right)\frac{n_{1}-n_{0}}{t} T_{L} = \frac{gm_{LS}(\sin\theta+\mu\cos\theta)p}{2\pi \eta} \tau_{M} = K_{S}(T_{L}+T_{a}) P=\tau_{M}\left(\frac{2\pi}{rev}\right)\left(\frac{min}{60s}\right)n_{1} v_1 = n_1\left(\frac{p}{60}\right)=n_1\left(\frac{m}{rev}\right)\left(\frac{min}{60s}\right)

Mass of the load (m_{LS}):	kg
Screw angle (\theta):	degrees
Initial motor velocity (n_{0}):	rpm
Final motor velocity (n_{1}):	rpm
Acceleration time (t):	sec
Screw pitch (p):	m/rev
Inertia of the screw (J_{S}):	kg*m2
Inertia of the motor (J_{M}):	kg*m2 (see motor spec.)
Friction coefficient (\mu):
Efficiency (\eta):	(0.85 to 0.95 ref.)
Safety Factor (K_{S}):	(1.5 to 2.0 ref.)
Acceleration Torque (T_{a}):
Load Torque (T_{L}):
Motor Torque (\tau_{M}):
Motor Power (P):
Motor Speed (v_1):