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Motor Selection Guide

Basic DATA for Calculation
설명이미지
If you enter values in the yellow fields, the rest of the values are calculated automatically.
  • Total weight of table & work
    W = kgf
  • External Force
    FE = kgf
  • Total mass of table & work
    m = kg
  • Gravitational acceleration
    g = m/sec²
  • Coefficient of Friction
    μ =
  • sin α
    =
  • Ball Screw Operation Efficiency
    ηB = 90%
  • cos α
      =
  • Pre-load Coefficient of internal friction of Nut
    μ0 =
  • Installation angle
    α = ˚
  • Ball Screw Diameter
    D = cm
  • Travel Distance
    = cm
  • Ball Screw whole length
    L = cm
  • Positioning Time
    t0 = sec
  • Ball Screw Pitch
    P = cm
  • Time of Acc/Dec
    t1 = sec
  • Ball Screw Material Density
    ρ = kg/cm³
  • Gear Ratio
    R =
  • Timing Belt Operation Efficiency
    ηT = 90%
  • Gear Efficiency
    ηR = 0%
  • Pulley 1 Diameter(Motor side)
    Dp1 = cm
  • Pulley Gear Ratio
    Rp = Dp2/Dp1
  • Pulley 1 Width(Motor Side)
    Lp1 = cm
  • Safety Factor
    S =
  • Pulley 2 Diameter(Load Side)
    Dp2 = cm
  • Encoder Resolution
      = ppr
  • Pulley 2 Width(Load Side)
    Lp2 = cm
  • Angle Resolution
    Δθ = *
  • Pulley Material Density
    ρP = kg/cm³
Operation Speed and Acceleration Calculation
  • Work linearvelocity
    V =
    • I
    • t0 - t1
    =
    • -
    = cm/sec
  • Ball Screw Revolution Velocity
    ωB = (V/P) = rad/sec = rpm
  • Pulley2(Load Side)Revolution Velocity
    ωP2 = ωB = rpm
  • Pulley1(Motor Side)Revolution Velocity
    ωP1 = ωP2 × RP = rad/sec
  • Operating Motor Revolution Angular Velocity
    ωM = ωP2 × R = rad/sec = rpm
  • Operating Motor Resolution Angular Acceleration
    ωM =
    • ωM
    • t1
    =
    = rad/sec²
  • Consider Rotor's Inertia Moment as J0 = 0,
  • Motor Operation Torque
    TM = so, from FASTEH Motor Torque curves
  • Operating motor revolution velocity
    ω M = rpm at
  • Operating Torque is
    T M = Select motor offers over N.m from curves
Verify validation of selected motor
View rotor moment of inertia
Rotor moment of inertia
로터 관성 모멘트
  • From selected motor spec, need to file out inertia moment J0
  • J0 g · cm² = kg · cm² kg · m²
  • Motor's operating Torque re-calculation with consideration of motor inertia moment
  • T N·m
  • [ Verify validation of selected motor ]
  • From selected motor's torque curve
  • Selected motor's revolution velocity
    ωM = rpm at
  • Selected motor's torque is
    T = is over : OK.
  • Selected motor's torque is
    T = is less than : NG.
  • Repeat Motor selection and Verify Validation width increasing motor's length or size
Check Load’s Intertia Moment Ratio K
  • K =
    • JL
    • J0 ×
    =
    • × ²
    =
  • Check Load's Intertia Moment Ratio K
    Can operate but motor's inappropriate opation (vibrating at Acc/Dec) can be happened So, please input enough Acc/Dec and need to decrease operation speed If you can't control Acc/Dec and need to decrease operation speed, please increase one level of motor's length or size, We would like to recommend to choose bigger motor has higher inertia moment. In case of using reducer, even selected motor's operation torque is enough but load inertia moment ratio "K" is not satisfied, We would like to recomment to choose incrased ration of reducer.