US4884941A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Active compliant end-effector with force, angular position, and angular velocity sensing
Assignee: University of Minnesota System
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Filing: 1987-03-30
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Granted: 1989-12-05
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Expires: 2007-03-30
Abstract
Abstract A direct-drive active compliant end-effector (10) comprises a planar linkage (28) having input links (30, 44) driven by motors (24, 26). A force sensor (52) is connected between the output link (36) and a tool mount (48) for measuring tool interaction forces, signals representative of which together with those representative of angular displacement and velocity of the input links (30, 44) are used by a controller (82) for controlling the drive motors (24, 26) to provide active electronic compliancy.
Inventors
- 👤 Homayoon Kazerooni
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 02:48
CPC Classifications
B; B25; B25J; B25J9/00; B25J9/10; B25J9/106; B24; B24B; B24B9/00; B25J13/00; B25J13/08; B25J13/088; B25J15/00; B25J15/0019; B25J17/00; B25J17/02; B25J17/0208; B25J19/00; B25J19/02; B25J19/028; B25J9/12; Y; Y10; Y10S; Y10S414/00; Y10S414/13; Y10T; Y10T74/00; Y10T74/20; Y10T74/20207
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
218 words
An end-effector for use with a robotic manipulator, comprising: a linkage including an output link, a first drive link and a connecting link each coupled at one end in a spaced-apart relationship to the output link, and a second drive link coupled at one end to the other end of the connecting link; means for mounting a tool on the output link of said linkage; first rotary drive means coupled to the other end of the first drive link of said linkage for applying torque thereto and for generating signals representative of its angular displacement and angular velocity; second rotary drive means coupled to the other end of the second drive link of said linkage for applying torque thereto and for generating signals representative of its angular displacement and angular velocity; and sensor means connected between said tool mounting means and the output link of said linkage for generating signals representative of forces in orthogonal directions parallel to the plane of the output link of said linkage upon interaction of the tool with a workpiece; said first and second rotary drive means each being responsive to said angular displacement, angular velocity and force signals for applying controlled torque to said linkage in order to achieve active electronic compliancy between the tool and manipulator upon interaction with the workpiece.
Claim 2
Dependent Claim
218 words
An end-effector for use with a robotic manipulator, comprising: a linkage including an output link, a first drive link and a connecting link each coupled at one end in a spaced-apart relationship to the output link, and a second drive link coupled at one end to the other end of the connecting link; means for mounting a tool on the output link of said linkage; first rotary drive means coupled to the other end of the first drive link of said linkage for applying torque thereto and for generating signals representative of its angular displacement and angular velocity; second rotary drive means coupled to the other end of the second drive link of said linkage for applying torque thereto and for generating signals representative of its angular displacement and angular velocity; and sensor means connected between said tool mounting means and the output link of said linkage for generating signals representative of forces in orthogonal directions parallel to the plane of the output link of said linkage upon interaction of the tool with a workpiece; said first and second rotary drive means each being responsive to said angular displacement, angular velocity and force signals for applying controlled torque to said linkage in order to achieve active electronic compliancy between the tool and manipulator upon interaction with the workpiece.
Claim 3
Dependent Claim
19 words
The end-effector of claim 1, wherein said first rotary drive means comprises a brushless, DC motor with a resolver.
Claim 4
Dependent Claim
19 words
The end-effector of claim 1, wherein said second rotary drive means comprises a brushless, DC motor with a resolver.
Claim 5
Dependent Claim
32 words
The end-effector of claim 1, wherein said sensor means for generating signals representative of orthogonal forces parallel to the plane of the output link of said linkage comprises a piezoelectric force transducer.
Claim 6
Dependent Claim
271 words
An end-effector for use with a robotic manipulator and with a controller for electronically controlling compliancy between the manipulator and a tool interacting with a workpiece, comprising: a linkage including a first drive link, an output link coupled at one end to the first drive link, a connecting link coupled at one end to the other end of said output link, and a second drive link coupled to the other end of said connecting link; the tool being mounted on the output link of said linkage; a first motor including a shaft drivingly connected directly to the first drive link of said linkage, said first motor including a resolver for generating signals representative of angular displacement and angular velocity of the first drive link; a second motor including a shaft drivingly connected directly to the second drive link of said linkage, said second motor including a resolver for generating signals representative of the angular displacement and angular velocity of the second drive link; means for supporting said first and second motors on the robotic manipulator with their shafts in fixed relative spaced-apart positions; and sensor means connected between the tool and the output link of said linkage for sensing forces, in two directions in a plane parallel to the plane of the output link of said linkage upon interaction of the tool with the workpiece, and generating signals representative thereof; and the controller being responsive to the angular displacement and angular velocity signals of said first and second motors and the force signals from said sensor means to control torque applied by said motors in order to achieve active electronic compliance.
Claim 7
Dependent Claim
271 words
An end-effector for use with a robotic manipulator and with a controller for electronically controlling compliancy between the manipulator and a tool interacting with a workpiece, comprising: a linkage including a first drive link, an output link coupled at one end to the first drive link, a connecting link coupled at one end to the other end of said output link, and a second drive link coupled to the other end of said connecting link; the tool being mounted on the output link of said linkage; a first motor including a shaft drivingly connected directly to the first drive link of said linkage, said first motor including a resolver for generating signals representative of angular displacement and angular velocity of the first drive link; a second motor including a shaft drivingly connected directly to the second drive link of said linkage, said second motor including a resolver for generating signals representative of the angular displacement and angular velocity of the second drive link; means for supporting said first and second motors on the robotic manipulator with their shafts in fixed relative spaced-apart positions; and sensor means connected between the tool and the output link of said linkage for sensing forces, in two directions in a plane parallel to the plane of the output link of said linkage upon interaction of the tool with the workpiece, and generating signals representative thereof; and the controller being responsive to the angular displacement and angular velocity signals of said first and second motors and the force signals from said sensor means to control torque applied by said motors in order to achieve active electronic compliance.
Claim 8
Dependent Claim
14 words
The end-effector of claim 5, wherein said first motor comprises a brushless DC motor.
Claim 9
Dependent Claim
14 words
The end-effector of claim 5, wherein said second motor comprises a brushless DC motor.
Claim 10
Dependent Claim
30 words
The end-effector of claim 5, wherein the directions of the forces sensed by said sensor means parallel to the plane of the output link of said linkage are mutually orthogonal.
Claim 11
Dependent Claim
15 words
The end-effector of claim 5, wherein said sensor means comprises a two-dimensional piezoelectric force transducer.
Claim 12
Dependent Claim
16 words
The end-effector of claim 5, further including: means for insulating said sensor means from spurious signals.
Claim 13
Dependent Claim
256 words
An end-effector system for connection between a robotic manipulator and a tool, comprising: a linkage including a first drive link, an output link coupled at one end to the first drive link, a connecting link coupled at one end to the other end of said output link, and a second drive link coupled to the other end of said connecting link; the first drive link and connecting link extending transverse to the output link, and the second drive link extending transverse to the connecting link, with the tool being mounted on the output link of said linkage; a first motor drivingly connected to the first drive link of said linkage, said first motor including a resolver for generating signals representative of angular displacement and angular velocity of the first drive link; a second motor drivingly connected to the second drive link of said linkage, said second motor including a resolver for generating signals representative of the angular displacement and angular velocity of the second drive link; sensor means connected between the tool and the output link of said linkage for sensing forces, in two directions in a plane parallel to the plane of the output link of said linkage upon interaction of the tool with a workpiece, and generating signals representative thereof; and means for individually controlling said first and second motors responsive to their angular displacement and angular velocity signals and the force signals from said sensor means in order to achieve active electronic compliance between the manipulator and tool during interaction with the workpiece.
Claim 14
Dependent Claim
256 words
An end-effector system for connection between a robotic manipulator and a tool, comprising: a linkage including a first drive link, an output link coupled at one end to the first drive link, a connecting link coupled at one end to the other end of said output link, and a second drive link coupled to the other end of said connecting link; the first drive link and connecting link extending transverse to the output link, and the second drive link extending transverse to the connecting link, with the tool being mounted on the output link of said linkage; a first motor drivingly connected to the first drive link of said linkage, said first motor including a resolver for generating signals representative of angular displacement and angular velocity of the first drive link; a second motor drivingly connected to the second drive link of said linkage, said second motor including a resolver for generating signals representative of the angular displacement and angular velocity of the second drive link; sensor means connected between the tool and the output link of said linkage for sensing forces, in two directions in a plane parallel to the plane of the output link of said linkage upon interaction of the tool with a workpiece, and generating signals representative thereof; and means for individually controlling said first and second motors responsive to their angular displacement and angular velocity signals and the force signals from said sensor means in order to achieve active electronic compliance between the manipulator and tool during interaction with the workpiece.
Claim 15
Dependent Claim
18 words
The end-effector system of claim 11, wherein said first motor comprises a brushless, DC motor with a resolver.
Claim 16
Dependent Claim
21 words
The end-effector system of claim 11, wherein said first and second motors each comprises a brushless, DC motor with a resolver.
Claim 17
Dependent Claim
21 words
The end-effector system according to claim 13, wherein the directions of the forces sensed by said sensor means are mutually orthogonal.
Claim 18
Dependent Claim
16 words
The end-effector system according to claim 14, wherein said sensor means comprises a piezoelectric force transducer.
References Cited (Backward Citations)
JPS5231456A
Cited
US4098001A
Cited
US4155169A
Cited
FR2460762A1
Cited
US4341502A
Cited
US4324032A
Cited
SU918081A1
Cited
US4491760A
Cited
US4633414A
Cited
US4523409A
Cited
US4621332A
Cited
US4603511A
Cited
US4706004A
Cited
US4637775A
Cited
US4712971A
Cited
US4668146A
Cited
US4756662A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-12-04 | 1993-06-05 | 1993-12-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-12-04 | 1997-06-05 | 1997-12-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-12-04 | 2001-06-05 | 2001-12-05 | $7700.00 | Window Closed / Lapsed |