Controlled bending actuator system

• US 5,933,002 A
• Filed: 11/07/1996
• Issued: 08/03/1999
• Est. Priority Date: 01/28/1991
• Status: Expired due to Term

• Current Assignee: SARCOS LC (Sarcos Technology & Robotics Corp.)
• Original Assignee: SARCOS LC (Sarcos Technology & Robotics Corp.)
• Inventors: Wells, David L., Jacobsen, Stephen L.
• Primary Examiner(s): Nguyen, Vinh P.
• Application Number:
  US08/744,368
• Time in Patent Office: 999 Days
• Field of Search: 324/106, 324/99 R, 324/117 R, 324/130, 324/73.1, 324/158.1, 324/132, 73/767, 73/862.631, 73/849, 73/794, 73/795, 702/104
• US Class Current: 324/99.00R
• CPC Class Codes: B23K 15/002 Devices involving relative movement between electronbeam and workpiece
• CPC Class Codes: B23K 17/00 Use of the energy of nuclear particles in welding or related techniques
• CPC Class Codes: B23K 26/08 Devices involving relative movement between laser beam and workpiece
• CPC Class Codes: G01B 7/24 using change in magnetic properties
• CPC Class Codes: G01D 5/12 using electric or magnetic means G01D5/06 takes precedence
• CPC Class Codes: G01K 5/483 using materials with a configuration memory, e.g. Ni-Ti alloys
• CPC Class Codes: G01P 13/04 Indicating positive or negative direction of a linear movement or clockwise or anti-clockwise direction of a rotational movement
• CPC Class Codes: G01P 15/08 with conversion into electric or magnetic values
• CPC Class Codes: G01P 15/0922 of the bending or flexing mode type
• CPC Class Codes: G01P 15/133 with piezoelectric counterbalancing means
• CPC Class Codes: G01P 15/18 in two or more dimensions
• CPC Class Codes: G02B 6/12002 Three-dimensional structures
• CPC Class Codes: G02B 6/43 Arrangements comprising a plurality of opto-electronic elements and associated optical interconnections
• CPC Class Codes: G03F 7/70691 Handling of masks or workpieces
• CPC Class Codes: G05B 19/186 Generation of screw- or gearlike surfaces
• CPC Class Codes: G09F 9/33 being semiconductor devices, e.g. diodes
• CPC Class Codes: G12B 1/00 Sensitive elements capable of producing movement or displacement for purposes not limited to measurement; Associated transmission mechanisms therefor
• CPC Class Codes: H01L 21/4846 Leads on or in insulating or insulated substrates, e.g. metallisation H01L21/4821 takes precedence; metallisation of ceramics in general C04B41/51; printed circuits H05K3/00
• CPC Class Codes: H01L 21/67011 Apparatus for manufacture or treatment processes H01L21/30, H01L21/46; for production or after-treatment of single crystals or homogeneous polycrystalline material C30B35/00
• CPC Class Codes: H01L 21/68 for positioning, orientation or alignment
• CPC Class Codes: H01L 25/065 : the devices being of a type provided for in group H01L27/00
• CPC Class Codes: H01L 25/162 : the devices being mounted on two or more different substrates
• CPC Class Codes: H01L 29/0657 : characterised by the shape of the body
• CPC Class Codes: H01L 2924/00 : Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 : Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H10N 30/2042 : Cantilevers, i.e. having one fixed end
• CPC Class Codes: H10N 30/304 : Beam type
• CPC Class Codes: H10N 30/306 : Cantilevers

Abstract

Controlled bending movement of a flexible elongate rod or filament in response to a bend signal indicative of a desired amount of bending is effected by a strip of shape-changing material disposed on a first side of an elongate rod element, the shape changing material changing shape in response to an actuation signal, thereby causing the filament element to bend, and a sensor including a strain gauge disposed on the rod element on a second side opposite the first side, said sensor sensing the amount of bend in the rod element from strain indicated, and a feedback control comparing the amount of bend of the filament sensed to a desired amount of bend defined by said bend signal and altering the actuation signal as required to make the amount of bend sensed the same as the amount of bend desired.

Claims

1. An actuator comprising

an elongate rod element of flexible material;

a strip of actuable material which changes shape in response to an actuation signal, said strip of actuable material being disposed on the surface of a first side of the element, said actuable material being responsive to an actuation signal for changing its shape to thereby cause the rod element to bend in an imaginary plane which extends through the strip and rod element;

a bending sensor further comprising a strain gauge disposed on the surface of the rod element on a second side opposite said first side to develop a signal indicating the amount of bend based on strain occurring at said surface on the second side of the elongate rod element;

a feedback control responsive to said signal indicating the amount of bend based on strain occurring and a signal indicative of a desired amount of bend of the elongate rod element, said feedback control supplying said actuation signal to the actuable material to cause bending such that the signal indicating the amount of bend based on strain occurring at said surface on the second side of the elongate rod element comes to indicate an amount of bend equal to said desired amount of bend of the elongate rod element; and

a signal source supplying said signal indicative of a desired amount of bend of the elongate rod element to the feedback control.