Title :
A novel actuation mechanism based on ferromagnetic SMA thin films
Author :
Kohl, M. ; Brugger, D. ; Ohtsuka, M. ; Takagi, T.
Author_Institution :
Forschungszentrum Karlsruhe GmbH, Germany
Abstract :
A novel actuation mechanism is presented, which makes use of the antagonism of intrinsic magnetic and shape recovery forces acting on a ferromagnetic shape memory alloy (SMA) microactuator in a magnetic field. This mechanism is associated with large actuation and small biasing forces in each actuation direction resulting in a large stroke. Since no external biasing elements are required, extremely compact designs are possible. As a demonstrator, an optical microscanner of 9/spl times/3/spl times/5 mm/sup 3/ size is presented showing large scanning angles up to 75 deg in off-resonance mode. The scanning performance keeps frequency-independent below a critical frequency, which is determined by heat-transfer times.
Keywords :
ferromagnetic materials; gallium alloys; magnetic forces; magnetic thin films; manganese alloys; microactuators; nickel alloys; optical scanners; NiMnGa; actuation; biasing forces; ferromagnetic SMA thin films; ferromagnetic shape memory alloy; heat-transfer times; magnetic field; magnetic force; microactuator; optical microscanner; shape recovery force; Frequency; Magnetic fields; Magnetic materials; Optical films; Optical scattering; Shape memory alloys; Sputtering; Temperature sensors; Transducers; Transistors;
Conference_Titel :
TRANSDUCERS, Solid-State Sensors, Actuators and Microsystems, 12th International Conference on, 2003
Conference_Location :
Boston, MA, USA
Print_ISBN :
0-7803-7731-1
DOI :
10.1109/SENSOR.2003.1216939
