Fast reversible NiTi fibers for use in microrobotics

Abstract

The authors report the experimentally determined characteristics of NiTi fibers which have been modified using a preparation procedure in which the fibers were subjected to brief very large current pulses during forced stretching. The modified fibers contract and relax fast enough to be of use in microrobotics. The modified fibers generate a maximum extrapolated stress of 230 MN/m/sup 2/ and yield a peak measured power/mass approaching 50 kW/kg. The theory of a micro-actuator incorporating the modified fibers is presented.<>