Linear Actuator Force Calculator

Force from a Screw-Driven Linear Actuator

A screw-type linear actuator converts rotary motor torque into linear thrust through its lead screw. The output force is F = (2πTη) / lead, where T is motor torque, lead is the linear travel per screw revolution, and η is the mechanical efficiency accounting for friction losses.

A finer lead (less travel per revolution) produces more force for the same torque, but moves more slowly — this is the same trade-off seen in any gear reduction. Typical lead-screw efficiencies range from about 30% for standard acme threads to over 90% for ball screws.