For high-speed low-load transmission systems, operational smoothness is often overlooked. Hidden precision defects such as backlash vibration and inertial drift frequently plague equipment. Many engineers only prioritize speed during selection while ignoring the matching between lead and working conditions, severely undermining overall equipment stability.
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Match screw critical speed and system inertia first
For high-speed low-load applications, the selected lead must guarantee the maximum operating speed stays within a safe margin below the screw critical speed. Meanwhile, calculate the load inertia converted to the motor side to maintain an inertia ratio within a range that the servo stiffness can suppress high-frequency vibration fundamentally.
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Derive the upper lead limit based on acceleration response
Calculate the maximum angular acceleration from the motor peak torque and total converted system inertia to limit the linear acceleration generated by the lead. Avoid abrupt acceleration caused by oversized leads, which triggers structural resonance and sharp increases in following error.
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Check position loop gain and velocity feedforward
After lead selection, verify whether the position loop bandwidth and velocity feedforward coefficient can stabilize dynamic following errors at maximum speed. Excessively steep velocity command slopes from improper leads cause velocity loop overshoot and periodic drift at constant speed.
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Account for nonlinear effects of backlash and friction torque
Small leads improve positioning resolution yet amplify low-speed friction nonlinearity; large leads reduce driving torque margin during reversal. Select a lead that balances friction torque proportion and minimizes reverse overshoot to restrain backlash vibration and stick-slip during direction changes.
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Avoid modal resonance via guide rigidity and mounting base
Integrate screw support types (fixed-supported / fixed-fixed) and slider preload grades into selection. Ensure excitation frequencies corresponding to the lead do not align with natural modes of worktables or bases, eliminating resonance drift induced by minor disturbances under high-speed low-load operation.
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Validate stability across full speed ranges via dynamic simulation
Run simulations covering acceleration, deceleration, constant speed and micro-feed motion curves to evaluate position fluctuation and velocity ripple. Choose the lead with sufficient damping across all speed segments instead of calculating merely based on extreme speed or static torque.
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