Patent US5136201A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5136201A Expired / Lapsed US ⏱️ 0.0 years remaining

Piezoelectric robotic articulation

Assignee: Boeing North American Inc
•
Filing: 1991-04-15
•
Granted: 1992-08-04
•
Expires: 2011-04-15
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Actuators of rigid electrically actuatable material provide articulation for robotic limbs. Piezoelectric actuators, for example, may be used in various embodiments of robotic joints to rotate a cylindrical or spherical connection or to translate a rod. Opposing pairs of actuators engage in smooth walking motion and maintain a vise-like grip on the robot limb at all times. The traction surfaces of the actuators contact the robot limb with zero clearance. Unlike the use of conventional bearings, zero clearance and full area contact provide relatively large mechanical stiffness that allows very precise positioning of robot limbs without mechanical oscillations of the extremities. With adequate limb rigidity, slop is essentially eliminated from the joints. The smooth walking motion of the actuators achieves high mechanical efficiency by eliminating sliding friction. The joints operate in air or space vacuum without lubrication and with negligible heating. Relatively large forces and torques are developed at relatively slow speeds. Size of the robotic joints can range from relatively large to microscopic.

Inventors

  • 👤 Gordon W. Culp

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 11:53
CPC Classifications
B; B25; B25J; B25J17/00; B62; B62D; B62D57/00; B62D57/02; B62D57/032; B25J17/02; B25J17/0241; B25J17/0258; B25J17/0275; B25J5/00; B25J9/00; B25J9/10; B25J9/12; H; H02; H02N; H02N2/00; H02N2/02; H02N2/021; H02N2/028; H02N2/10; H02N2/101; H02N2/108; H10; H10N; H10N30/00; H10N30/20; H10N30/202; H10N30/2023

Claims Analysis

Total Claims: 21
Claim 1
Independent Claim 74 words
A robotic articulation comprising: an articulator housing attached to a robot body, at least two pair of actuators mounted in said housing, each of said actuators comprising a stack of electrically actuable material having a lifter segment, a tangenter segment, and a traction surface for engaging an articulable robot limb having an end extending within said housing, wherein the pairs of actuators alternately act in a vice-like manner to grip and move said limb.
Claim 2
Dependent Claim 74 words
A robotic articulation comprising: an articulator housing attached to a robot body, at least two pair of actuators mounted in said housing, each of said actuators comprising a stack of electrically actuable material having a lifter segment, a tangenter segment, and a traction surface for engaging an articulable robot limb having an end extending within said housing, wherein the pairs of actuators alternately act in a vice-like manner to grip and move said limb.
Claim 3
Dependent Claim 65 words
The robotic articulation of claim 1 wherein each pair actuators operates in a cycle having the steps of, contacting the limb while moving at the same speed as the limb, in order to eliminate rubbing friction during contact, moving the limb, lifting off the limb while moving at the same speed as the limb to eliminate rubbing friction during contact, retracing to begin another cycle.
Claim 4
Dependent Claim 44 words
The robotic articulation of claim 1, wherein said end of said limb comprises a rod having a rectangular cross section, said housing includes a rectangular opening, and said actuators comprise two pairs of opposing actuators mounted in said rectangular opening for engaging said rod.
Claim 5
Dependent Claim 44 words
The robotic articulation of claim 1, wherein said end of said limb comprises a cylindrical shaft, said housing includes a cylindrical opening, and said actuators comprise at least two pairs of opposing cylindrical arcs mounted in said cylindrical opening for engaging said cylindrical shaft.
Claim 6
Dependent Claim 24 words
The robotic articulation of claim 4, wherein said robot limb further comprises an upper leg and a lower leg connected by a knee joint.
Claim 7
Dependent Claim 38 words
The robotic articulation of claim 5, wherein said knee joint comprises a knee housing and a plurality of knee actuators mounted in said knee housing for engaging an end of said lower leg extending within said knee housing.
Claim 8
Dependent Claim 44 words
The robotic articulation of claim 2, wherein said end of said limb comprises a rod having a rectangular cross section, said housing includes a rectangular opening, and said actuators comprise two pairs of opposing actuators mounted in said rectangular opening for engaging said rod.
Claim 9
Dependent Claim 44 words
The robotic articulation of claim 2, wherein said end of said limb comprises a cylindrical shaft, said housing includes a cylindrical opening, and said actuators comprise at least two pairs of opposing cylindrical arcs mounted in said cylindrical opening for engaging said cylindrical shaft.
Claim 10
Dependent Claim 18 words
The robotic articulation of claim 7, wherein the electrically actuable material of the actuators is a piezoelectric material.
Claim 11
Dependent Claim 18 words
The robotic articulation of claim 3, wherein the electrically actuable material of the actuators is a piezoelectric material.
Claim 12
Dependent Claim 36 words
The robotic articulation of claim 1, wherein said end of said limb comprises a ball, said housing comprises a spherical cavity and said pairs of actuators are mounted on said spherical cavity and engage said ball.
Claim 13
Dependent Claim 18 words
The robotic articulation of claim 1, wherein the electrically actuable material of the actuators is a piezoelectric material.
Claim 14
Dependent Claim 18 words
The robotic articulation of claim 4, wherein the electrically actuable material of the actuators is a piezoelectric material.
Claim 15
Dependent Claim 18 words
The robotic articulation of claim 11, wherein the electrically actuable material of the actuators is a piezoelectric material.
Claim 16
Dependent Claim 36 words
The robotic articulation of claim 2, wherein said end of said limb comprises a ball, said housing comprises a spherical cavity and said pairs of actuators are mounted on said spherical cavity and engage said ball.
Claim 17
Dependent Claim 18 words
The robotic articulation of claim 2, wherein the electrically actuable material of the actuators is a piezoelectric material.
Claim 18
Dependent Claim 24 words
The robotic articulation of claim 8, wherein said robot limb further comprises an upper leg and a lower leg connected by a knee joint.
Claim 19
Dependent Claim 38 words
The robotic articulation of claim 17, wherein said knee joint comprises a knee housing and a plurality of knee actuators mounted in said knee housing for engaging an end of said lower leg extending within said knee housing.
Claim 20
Dependent Claim 18 words
The robotic articulation of claim 8, wherein the electrically actuable material of the actuators is a piezoelectric material.
Claim 21
Dependent Claim 18 words
The robotic articulation of claim 15, wherein the electrically actuable material of the actuators is a piezoelectric material.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-08-04 1996-02-03 1996-08-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-08-04 2000-02-03 2000-08-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-08-04 2004-02-03 2004-08-04 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag