Description:This research investigates smart
material actuators and valve concepts. Specically, a prototype pilot stage nozzle
ap-
per valve is developed for the purpose of actuating a main stage spool. The typical
nozzle
apper type servo valve uses a torque motor to actuate the
apper. In this
research project, the torque motor has been substituted for two piezoelectric ring ben-
der actuators. A novel mounting mechanism has been developed to secure the ring
benders within the valve. Analytical and nite element models have been made to
understand the displacement mechanism of a ring bender and the eects of the mount
on the displacement and force from a ring bender, and the results were compared with
experiment. The mounting stiness at the inner and outer edges was found to decrease
the displacement of the ring bender and it was found that the stiness of the mount
at the outer edge has a greater negative eect on displacement than the stiness of the
mount at the inner edge.