Claims
- 1. A torsional actuator comprising:
- a) a plurality of segments, each segment having a length L, each segment comprised of an electroactive material which is poled along its length dimension, said plurality of segments arranged side by side into a cylindrical cross-sectional arrangement exhibiting a radius R, wherein a ratio of L to R is a value greater than one, said ratio greater than one assuring an amplification of rotational displacement of said cylindrical cross-section in accord with said ratio, adjacent segments arranged so that their respective polings are in opposed directions;
- b) conductive means positioned between adjacent edges of said side-by-side segments;
- c) means for fixing first-ends of said side-by-side segments with respect to second ends thereof; and
- d) additional cylindrical shaped torsional actuators positioned about said torsional actuator of cylindrical shape, each of said additional cylindrical shaped torsional actuators constructed as recited in paragraphs a)-c);
- e) power supply means connected to said conductive means for applying oppositely poled electric fields across said side-by-side segments to cause shear deformations of each of said adjacent segments; and
- f) means for binding together said torsional actuator of cylindrical shape and said additional cylindrical shaped torsional actuators so as to achieve concurrent rotational movement of said second ends of each thereof.
- 2. The torsional actuator as recited in claim 1 wherein said electroactive material is a piezoelectric comprising lead, zirconium and titanium.
- 3. The torsional actuator as recited in claim 1 wherein said electroactive material is selected from the group consisting of ceramic piezoelectric materials, single crystal piezoelectric materials and polymeric piezoelectric materials.
- 4. The torsional actuator as recited in claim 1 wherein said conductive means comprises a conductor incorporated into a composite polymeric material.
- 5. The torsional actuator as recited in claim 1 wherein said second ends are arranged to engage an object to be rotatively moved.
GOVERNMENT SPONSORSHIP
This invention was made with Government support under Contract No. N00014-92-J-1510 awarded by the U.S. Department of the Navy. The Government has certain rights in the invention.
US Referenced Citations (8)
Non-Patent Literature Citations (1)
Entry |
"Piezoelectric Torsional Actuator", Fuda et al., Ferroelectrics, vol. 160, pp. 323-330 (1994). |