Tool arrays for biomedical surgery where the tools consist of layered
polymer micromuscles arranged to induce geometrical changes and movements
via an electrochemically induced change of volume in at least one polymer
layer. The tool or tool arrays are mounted on a carrier having the form
of a needle being inserted into a cannula/catheter through which the
tools can be electrically actuated via external means to induce a
mechanical movement to act upon biological structures.