[ 11 ]lab · simulations

Stepper torque vs speed

A first-order estimate of pull-out torque against speed: flat at the holding torque out to a corner speed, then falling roughly as 1/omega once back-EMF and inductance eat the supply's voltage headroom. Not a datasheet curve.

lab · sims · stepper torque/speed

Gear train →Ratio, direction, planetary. Battery / power budget →Duty cycle to runtime. Thermal →Junction temperature and margin. Circuit basics →Ohm's law, dividers, LEDs, RC.

The curve [ live ]

pull-out torque vs speed, corner speed dashed

—corner speed

—max speed at load torque

—power at that speed

—torque constant K_t

—max accel, rotor only

Motor

holding torque (N·m) rated current (A/phase) phase resistance (Ω) phase inductance (mH)

Drive

supply voltage (V)

Load

load torque (N·m) rotor + load inertia (g·cm²)

Assumptions and limits. This is a first-order estimate, not a datasheet curve: real pull-out torque depends on the driver's current-control bandwidth, chopping scheme and microstepping resolution in ways this single-pole model does not capture, and holding torque itself is a static number that running torque never quite equals. The corner speed comes from a voltage balance - supply volts against I·Z (resistance and inductive reactance) plus back-EMF - solved numerically rather than a closed form. Microstepping changes smoothness and resolution far more than it changes the torque available at a given speed, so it is not folded into the curve here. Inertia is rotor-plus-load and only used for the no-load acceleration readout; it does not affect the plotted curve.