Electrically, Chemically, and Photonically Powered Torsional and Tensile Actuation of Hybrid Carbon Nanotube Yarn Muscles

TLDR

Nanotube yarn actuators convert heat, light, or electricity into twisting or tensile motion, yet existing materials either deliver large forces with small motions (e.g., NiTi) or large motions with low force (e.g., polymers) and often suffer from slow response and short lifetimes. The study shows that guest‑filled, twist‑spun carbon nanotube yarns can achieve linear or torsional actuation, address speed and lifetime issues, and operate without electrolytes. Reference: Lima et al.

Abstract

Nanotube Yarn Actuators Actuators are used to convert heat, light, or electricity into a twisting or tensile motion, and are often described as artificial muscles. Most materials that show actuation either provide larger forces with small-amplitude motions, such as the alloy NiTi, or provide larger motions with much less force, such as polymeric materials. Other problems with such actuators can include slow response times and short lifetimes. Lima et al. (p. 928 , see the Perspective by Schulz ) show that a range of guest-filled, twist-spun carbon nanotube yarns can be used for linear or torsional actuation, can solve the problems of speed and lifetime, and do not require electrolytes for operation.