Smart material control system and related method

• US 6,188,160 B1
• Filed: 09/11/1998
• Issued: 02/13/2001
• Est. Priority Date: 09/12/1997
• Status: Expired due to Fees

• Current Assignee: University Of Kentucky Research Foundation (University of Kentucky)
• Original Assignee: University Of Kentucky Research Foundation (University of Kentucky)
• Inventors: Main, John A., Nelson, George C.
• Primary Examiner(s): Dougherty, Thomas M.
• Application Number:
  US09/152,236
• Time in Patent Office: 886 Days
• Field of Search: 310/314, 310/317
• US Class Current: 310/314
• CPC Class Codes: H10N 30/04 Treatments to modify a piezoelectric or electrostrictive property, e.g. polarisation characteristics, vibration characteristics or mode tuning
• CPC Class Codes: H10N 30/2042 Cantilevers, i.e. having one fixed end

Abstract

A smart material control system and related method is disclosed for adaptively controlling the movement of an adaptive structure. The adaptive structure includes a smart material layer bonded to a conductive substrate in a bimorph configuration. A charge projector, such as an electron gun, is utilized to project charges onto the smart material layer of the adaptive structure. A voltage/charge source adaptively controls the potential of the conductive substrate. Depending on the placement of the projected charges and the adaptively controlled potential of the conductive substrate the displacement/curvature is precisely controlled. In an alternate embodiment, two smart material layers are bonded together to form an adaptive structure controlled independently in the x- and y- directions. Also, an array of charge projectors and/or conductive substrate sections may be used to provide varying and broad control of adaptive structures.

Claims

1. A system for controlling movement of an adaptive structure comprising:

an adaptive structure having first, second, third, and fourth layers, said first and second layers having a plurality of perforations;

a charge projector for projecting charges onto said first layer and through said perforations and onto said third layer of said adaptive structure,

whereby the movement of said first and third layers of said adaptive structure is independently controllable.

2. The system for controlling the movement of an adaptive structure of claim 1, wherein said first and third layers are smart material layers and said second and fourth layers are conductive substrates, said layers bonded together in a multimorph configuration.

3. The system for controlling the movement of an adaptive structure of claim 2 further comprising a voltage/charge source for selectively varying the potential of said second and fourth layers of said adaptive structure;

and

wherein said charge projector is a single energy electron gun.

4. A system for controlling the movement of an adaptive structure comprising:

an adaptive structure having first and second smart material layers, and a conductive substrate layer, wherein said first and second smart material layers are arranged such that polarities of said first and second smart material layers are opposing;

a charge projector for projecting charges onto said first layer of said adaptive structure; and

a variable voltage/charge source for selectively varying the potential of said conductive substrate layer of said adaptive structure,

whereby the displacement and/or curvature of said adaptive structure is dependent upon the placement of said charges and the potential of said conductive substrate layer of said adaptive structure.

5. The system for controlling the movement of an adaptive structure of claim 4, wherein said voltage/charge source for selectively varying the potential of said conductive substrate layer is an amplifier and said charge projector includes at least one single energy electron gun.

6. A method of controlling an adaptive structure bonded to a conductive substrate layer having a potential/charge comprising the steps of:

projecting charges onto a first smart material layer of said adaptive structure, said adaptive structure having first and second smart material layers arranged such that polarities of said first and second smart material layers are opposing;

selectively varying the potential/charge of said conductive substrate layer; and

wherein the displacement and/or curvature of said adaptive structure is dependent upon both the placement of said projected charges and the potential/charge on said conductive substrate layer.

7. The method of adaptively controlling an adaptive structure of claim 6 wherein the step of varying the potential/charge includes selectively polarizing said conductive substrate layer in order to shorten the time required to effect the displacement and/or curvature of said adaptive structure.