US5497061A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of controlling robot's compliance
Assignee: Hitachi Ltd
•
Filing: 1994-03-24
•
Granted: 1996-03-05
•
Expires: 2014-03-24
Abstract
Abstract A control system in which an end effector of a robot is mechanically compliant for a particular object. The robot has multiple degrees of freedom and movement and includes a sensor which senses a velocity nd a sensor which senses an external force. A virtual compliance control method is applied to the robot. Influence of the weight and gyro moment of the end effector is subtracted from a value obtained from a mechanism which senses the external force to set a term of the external force in a mathematic model of the control system constructed during control. By such arrangement, when a rotational body having a mechanically large rotational momentum is set as the end effector of the robot, the control system is mechanically compliant with the object.
Inventors
- 👤 Youichi Nonaka
- 👤 Shiyuki Sakaue
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 09:58
CPC Classifications
B; B25; B25J; B25J9/00; B25J9/16; B25J9/1628; B25J9/1633
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
134 words
A method of controlling the compliance of robot having multiple degrees of movement and freedom, said robot including means for sensing a velocity of an end effector and means for sensing an external force to the end effector, said method comprising the steps of: sensing the external force so that the motion of the end effector of said robot may have a proper mechanical compliance against the external force; calculating an angular momentum of a rotational body provided at the end effector of said robot, a gyro moment occurring at said rotational body due to the motion of said robot, a moment of inertia and rotational velocity of said rotational body and an operating velocity of said robot; and subtracting said gyro moment from the signal of said means for sensing the external force.
Claim 2
Independent Claim
134 words
A method of controlling the compliance of robot having multiple degrees of movement and freedom, said robot including means for sensing a velocity of an end effector and means for sensing an external force to the end effector, said method comprising the steps of: sensing the external force so that the motion of the end effector of said robot may have a proper mechanical compliance against the external force; calculating an angular momentum of a rotational body provided at the end effector of said robot, a gyro moment occurring at said rotational body due to the motion of said robot, a moment of inertia and rotational velocity of said rotational body and an operating velocity of said robot; and subtracting said gyro moment from the signal of said means for sensing the external force.
Claim 3
Independent Claim
153 words
A method of controlling the compliance of a robot having multiple degrees of movement and freedom, said robot including means for sensing a position of an end effector and means for sensing an external force to the end effector, said method comprising the steps of: sensing the external force so that the motion of the end effector of said robot may have a proper mechanical compliance against the external force; calculating an angular momentum of a rotational body provided at the end effector of said robot and a gyro moment occurring at said rotational body due to the motion of said robot, a moment of inertia and rotational velocity of said rotational body and an operating velocity of said robot obtained by differentiation of a signal of said means for sensing the position with respect to time; and subtracting said gyro moment from the signal of said means for sensing the external force.
Claim 4
Independent Claim
153 words
A method of controlling the compliance of a robot having multiple degrees of movement and freedom, said robot including means for sensing a position of an end effector and means for sensing an external force to the end effector, said method comprising the steps of: sensing the external force so that the motion of the end effector of said robot may have a proper mechanical compliance against the external force; calculating an angular momentum of a rotational body provided at the end effector of said robot and a gyro moment occurring at said rotational body due to the motion of said robot, a moment of inertia and rotational velocity of said rotational body and an operating velocity of said robot obtained by differentiation of a signal of said means for sensing the position with respect to time; and subtracting said gyro moment from the signal of said means for sensing the external force.
Claim 5
Independent Claim
148 words
A method of presuming an external force applied to an end effector of a robot having multiple degrees of movement and freedom, said robot including means for sensing velocity and means for sensing the external force, wherein a rotational body is provided at the end effector, said method comprising the steps of: calculating an angular momentum of said rotational body and a gyro moment occurring at said rotational body due to the motion of said robot, a moment of inertia and rotational velocity of said rotational body and an operating velocity of said robot; subtracting said gyro moment from the signal of said means for sensing the external force; and calculating the external force applied to said end effector from the positional relation between the contacting point of the subtracted signal and the external force applied to said end effector and said means for sensing the external force.
Claim 6
Independent Claim
148 words
A method of presuming an external force applied to an end effector of a robot having multiple degrees of movement and freedom, said robot including means for sensing velocity and means for sensing the external force, wherein a rotational body is provided at the end effector, said method comprising the steps of: calculating an angular momentum of said rotational body and a gyro moment occurring at said rotational body due to the motion of said robot, a moment of inertia and rotational velocity of said rotational body and an operating velocity of said robot; subtracting said gyro moment from the signal of said means for sensing the external force; and calculating the external force applied to said end effector from the positional relation between the contacting point of the subtracted signal and the external force applied to said end effector and said means for sensing the external force.
Claim 7
Independent Claim
133 words
A method of presuming a point of contact between an end effector of a robot having multiple degrees of movement and freedom, said robot including means for sensing velocity and means for sensing the external force, and an object, wherein a rotational body is provided at the end effector, said method comprising the steps of: calculating an angular momentum of said rotational body and a gyro moment occurring at said rotational body due to the motion of said robot, a moment of inertia and rotational velocity of said rotational body and an operating velocity of said robot; and subtracting said gyro movement from the signal of said means for sensing the external force; and calculating the point of contacts by utilizing the subtracted signal and information of the form of the end effector.
Claim 8
Independent Claim
133 words
A method of presuming a point of contact between an end effector of a robot having multiple degrees of movement and freedom, said robot including means for sensing velocity and means for sensing the external force, and an object, wherein a rotational body is provided at the end effector, said method comprising the steps of: calculating an angular momentum of said rotational body and a gyro moment occurring at said rotational body due to the motion of said robot, a moment of inertia and rotational velocity of said rotational body and an operating velocity of said robot; and subtracting said gyro movement from the signal of said means for sensing the external force; and calculating the point of contacts by utilizing the subtracted signal and information of the form of the end effector.
References Cited (Backward Citations)
JPS6235915A
Cited
US5023808A
Cited
US4949026A
Cited
US5206930A
Cited
US5159249A
Cited
US5056038A
Cited
US5224032A
Cited
US5115418A
Cited
US4999553A
Cited
US5260629A
Cited
US5179514A
Cited
US5193963A
Cited
US5239248A
Cited
US5220261A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-03-05 | 1999-09-04 | 2000-03-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-03-05 | 2003-09-04 | 2004-03-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-03-05 | 2007-09-04 | 2008-03-05 | $7700.00 | Window Closed / Lapsed |