MFGE 437 S21 - Homework 1 Submissions will be Online! Please scan your HWs and upload...

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MFGE 437 S21 - Homework 1 Submissions will be Online! Please scan your HWs and upload on Canvas Problem 1: A vertical milling machine is to be retrofitted with three identical DC servo motors. The following parameters are given for the X axis of the machine. Table Mass Workpiece Mass Leadscrew Mass Leadscrew (=Ballscrew) Pitch Leadscrew Diameter m.=20 [kg] mw=30[kg] m=2[kg] h = 0.02 [m/rev] d = 0.02 [m] Motor shaft, coupling, encoder & tachogenerator Jm = 2.875x10+ [kgm] inertias Gear Ratio Friction coefficient of Guideways Bearing friction coefficient Maximum Vertical Force Viscous Friction Coefficient of the Guideways Maximum Feed Force Preload Force on the Thrust Bearings Desired Acceleration of the Table r = 2 Har=0.1 th = 0.005 F = 1000 [N] b=0.005 [Nm/rad/sec] F = 5000 [N] F = 2000 [N] a = 5 [m/sec] 1. Compute the static torque required to when the axis travels at f=250[mm/sec]? [20pts) 2. Compute the max. dynamic torque required to speed up to the desired feed. (20pts) Note: The gear is placed between the motor and the ball-screw and it is providing torque advantage for the motor. (motor rotating more) Please clearly show calculations for the contribution each load item. MFGE 437 S21 - Homework 1 Submissions will be Online! Please scan your HWs and upload on Canvas Problem 1: A vertical milling machine is to be retrofitted with three identical DC servo motors. The following parameters are given for the X axis of the machine. Table Mass Workpiece Mass Leadscrew Mass Leadscrew (=Ballscrew) Pitch Leadscrew Diameter m.=20 [kg] mw=30[kg] m=2[kg] h = 0.02 [m/rev] d = 0.02 [m] Motor shaft, coupling, encoder & tachogenerator Jm = 2.875x10+ [kgm] inertias Gear Ratio Friction coefficient of Guideways Bearing friction coefficient Maximum Vertical Force Viscous Friction Coefficient of the Guideways Maximum Feed Force Preload Force on the Thrust Bearings Desired Acceleration of the Table r = 2 Har=0.1 th = 0.005 F = 1000 [N] b=0.005 [Nm/rad/sec] F = 5000 [N] F = 2000 [N] a = 5 [m/sec] 1. Compute the static torque required to when the axis travels at f=250[mm/sec]? [20pts) 2. Compute the max. dynamic torque required to speed up to the desired feed. (20pts) Note: The gear is placed between the motor and the ball-screw and it is providing torque advantage for the motor. (motor rotating more) Please clearly show calculations for the contribution each load item.