Micro Lead Screw

A screw only a few millimeters in diameter that turns a small motor's rotation into linear push-pull motion.

A micro lead screw is a screw, typically only a few millimeters in diameter, that comes in trapezoidal, ball, or planetary-roller variants, all serving to convert a motor's rotation into the nut's linear travel. In dexterous hands, a common approach pairs a coreless motor with a micro lead screw to make a small linear actuator, hidden inside the palm or a finger, pushing and pulling a linkage to curl the finger. A smaller lead (how far the nut travels per revolution) gives more push force but lower speed; a trapezoidal screw has more friction and can self-lock, so a finger can hold its grip even after power is cut. Humanoid robots need these in large volumes, and precision and lifespan remain a challenge for domestic manufacturing in China.

ExampleThe Linker Hand L20 from Linkerbot uses a brushless motor paired with a precision ball screw to drive a linkage that moves the finger joints.

Also called

Micro Ball Screw, Micro Planetary Roller Screw

Related

Coreless Motor · Ball Screw · Planetary Roller Screw · Trapezoidal Lead Screw & Self-Locking · Screw Lead · Linkage Transmission

Sources

Leadscrew - Wikipedia
灵心巧手 - 全球领先的机器人灵巧手 | LinkerBot (Chinese)