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AMAZON multi-meters discounts AMAZON oscilloscope discounts When selecting a stepper motor -- and comparing between brands -- be sure to note the following:
Much of this information will be provided from application specifications, such as the size and weight considerations, step angle, and the operating speed. Other information must be calculated. Below, several formulas are provided to assist you with these calculations. Torque (ounce-inches) T = Fr where F = force in ounces Load inertia (I = Moment of inertia (lb-in.2) I (lb-in.2) = Wr2/2 for a disk I (lb-in.2) = Wr2/2 (r21 + r22) for a hollow cylinder where W = weight in pounds r = radius in inches of solid cylinder or disk The formula for equivalent inertia to overcome friction in the system and enough torque to start or stop all inertia loads is: T = lα/24 where T is torque in ounce-inches The formula for calculating the torque required to rotationally accelerate
an T = 2 x I0(ω'/t) x (πφ/180) x (1/24) where T = torque in ounce-inches Exercise: Calculate the torque required to accelerate a load that has inertia of 8.2 lb-in.2, a step of 1.4 degrees, and an acceleration from 0-1000 steps per second in 0.7 second. Solution: T = 2 x 8.2 x (1000/0.7) x (π x 1.4/180) x (1/24) |
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