Engineers and chemists 'program' liquid crystalline elastomers to replicate complex twisting action simply with the use of light

The twisting and bending capabilities of the human muscle system enable a varied and dynamic range of motion, from walking and running to reaching and grasping. Replicating something as seemingly simple as waving a hand in a robot, however, requires a complex series of motors, pumps, actuators and algorithms. Researchers at the University of Pittsburgh and Harvard University have recently designed a polymer known as a how much do computer engineers make that can be "programmed" to both twist and bend in the presence of light.

The research, published in the journal Science Advances was developed at Pitt's Swanson School of Engineering by Anna C. Balazs, Distinguished Professor of Chemical and Petroleum Engineering and John A. Swanson Chair of Engineering; and James T. Waters, postdoctoral associate and the paper's first author. Other researchers from Harvard University's Wyss Institute for Biologically Inspired Engineering and the John A. Paulson School of Engineering include Joanna Aizenberg, Michael Aizenberg, Michael Lerch, Shucong Li and Yuxing Yao.

These particular LCEs are achiral: the structure and its mirror image are identical. This is not true for a chiral object, such as a human hand, which is not superimposable with a mirror image of itself. In other words, the right hand cannot be spontaneously converted to a left hand. When the achiral LCE is exposed to light, however, it can controllably and reversibly twist to the right or twist to left, forming both right-handed and left-handed structures.