Contents

12 July 2019
Vol 365, Issue 6449

About The Cover

Cover image expansion

COVER Upon heating, a strain-programmable fiber-based artificial muscle composed of thermoplastic and elastomer layers actuates a miniature printed arm and lifts a dumbbell 650 times its own weight. These fiber-based muscles, fabricated at lengths of hundreds of meters, are highly tunable in terms of power and lateral dimensions and thus may offer opportunities in robotics and prosthetics. See pages 125, 145, 150, and 155.
Photo: Ken Richardson