  Nematic elastomers are programmable soft materials that display large,
reversible and predictable deformation under an external stimulus such as a
change in temperature or light. While much of the work in the field has focused
on actuation from flat sheets, recent advances in 3D printing and other methods
of directed synthesis have motivated the study of actuation of curved shells.
Snap-through buckling has been a topic of particular interest. In this work, we
present theoretical calculations to motivate another mode of actuation that
combines programmable soft materials as well as instabilities associated with
large deformation. Specifically, we analyze the deformation of a cylindrical
shell of a patterned nematic elastomer under pressure, show that it can undergo
an enormous change of volume with changing temperature and suggest its
application as a pump with extremely high ejection fraction.
