US5898599A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Force reflecting haptic interface
Assignee: Massachusetts Institute of Technology
•
Filing: 1996-12-23
•
Granted: 1999-04-27
•
Expires: 2016-12-23
Abstract
Abstract An apparatus and method for physically exchanging a force with a user in a user-local environment. The apparatus includes a user connection element and a linkage physically linking the user connection element to a reference. The linkage provides at least six independent degrees of freedom to the user connection element. The linkage has an actuator system which powers at least three degrees of freedom of the user connection element, while at least three degrees of freedom remain unpowered. The method includes providing an apparatus which includes a user connection element and a linkage physically linking the user connection element to a reference, the linkage providing at least six independent degrees of freedom to the user connection element. The linkage of the apparatus provided has an actuator system which powers at least three of the six independent degrees of freedom relative to the reference. The method further includes connecting the user connection element to a body member of a user and powering at least three of the six independent degrees of freedom.
Inventors
- 👤 Thomas H Massie
- 👤 J. Kenneth Salisbury, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:56
CPC Classifications
B; B25; B25J; B25J9/00; B25J9/16; B25J9/1679; B25J9/1689; G; G05; G05B; G05B11/00; G05B11/01; B25J13/00; B25J13/02; G05B17/00; G05B17/02; G05G; G05G1/00; G05G1/52; G05G9/00; G05G9/02; G05G9/04; G05G9/047; G06; G06F; G06F3/00; G06F3/01; G06F3/011; G06F3/014; G06F3/016; G06F3/03; G06F3/033; G06F3/0346; G06F3/038; G06F3/0383; G06G; G06G7/00; G06G7/48; G05B2219/00; G05B2219/20; G05B2219/23; G05B2219/23021; G05G2009/04766; G06F2203/00; G06F2203/033; G06F2203/0331
Claims Analysis
Total Claims: 62
Claim 1
Independent Claim
168 words
An apparatus for generating a signal representative of force comprising: a. a receiver for receiving a signal representative of the location of a user reference point relative to a user reference frame; b. a geometry model residence for storing a representation of: i. a non-local reference frame; ii. the user reference frame, relative to said non-local reference frame; and iii. the conformation of a, non-local environment comprising a switch-type, spring-type element, relative to said non-local reference frame; c. a comparator for comparing the location of the user reference point relative to the non-local environment; and d. a force generator for generating a signal representative of a force, based on the location of the user reference point relative to the non-local environment and a set of force rules, including spring-force rules which specify a switch output force signal in response to a location signal of said user reference point indicative of a deflected conformation of said spring-type element, said switch output force signal being specified by a non-linear function.
Claim 2
Independent Claim
168 words
An apparatus for generating a signal representative of force comprising: a. a receiver for receiving a signal representative of the location of a user reference point relative to a user reference frame; b. a geometry model residence for storing a representation of: i. a non-local reference frame; ii. the user reference frame, relative to said non-local reference frame; and iii. the conformation of a, non-local environment comprising a switch-type, spring-type element, relative to said non-local reference frame; c. a comparator for comparing the location of the user reference point relative to the non-local environment; and d. a force generator for generating a signal representative of a force, based on the location of the user reference point relative to the non-local environment and a set of force rules, including spring-force rules which specify a switch output force signal in response to a location signal of said user reference point indicative of a deflected conformation of said spring-type element, said switch output force signal being specified by a non-linear function.
Claim 3
Dependent Claim
38 words
The apparatus of claim 1, further comprising a non-local environment reaction calculator that makes changes to the representation of the conformation of the non-local environment based on the signal representative of force and the set of force rules.
Claim 4
Dependent Claim
42 words
The apparatus of claim 2, said spring force rules specifying a change in the representation of the conformation of the non-local environment in response to a location signal of said user reference point indicative of a deflected conformation of said switch-type element.
Claim 5
Dependent Claim
28 words
The apparatus of claim 3, said change in the conformation of the non-local environment comprising a change in the conformation of the representation of the switch type element.
Claim 6
Dependent Claim
42 words
The apparatus of claim 4, said switch-type element comprising a switch having at least two positions, said change in conformation of the representation of the switch type element comprising a change from one position to another of said at least two positions.
Claim 7
Independent Claim
213 words
An apparatus for generating a signal representative of force comprising: a. a receiver for receiving a signal representative of the location of a user reference point relative to a user reference frame; b. a geometry model residence for storing a representation of: i. a non-local reference frame; ii. the user reference frame, relative to said non-local reference frame; and iii. the conformation of a, non-local environment comprising a diagonal-type, spring-type element, relative to said non-local reference frame; c. a comparator for comparing the location of the user reference point relative to the non-local environment; d. a force generator for generating a signal representative of a force, based on the location of the user reference point relative to the non-local environment and a set of force rules, including spring-force rules which specify a diagonal element output force signal in response to a location signal of said user reference point indicative of a deflected conformation of said diagonal-type element; and e. a non-local environment reaction calculator that makes changes to the representation of the conformation of the non-local environment based on the signal representative of force and the set of force rules, said diagonal element spring-type rule specifying a change in the representation of the cross-sectional area of a selected region of said diagonal-type element.
Claim 8
Independent Claim
213 words
An apparatus for generating a signal representative of force comprising: a. a receiver for receiving a signal representative of the location of a user reference point relative to a user reference frame; b. a geometry model residence for storing a representation of: i. a non-local reference frame; ii. the user reference frame, relative to said non-local reference frame; and iii. the conformation of a, non-local environment comprising a diagonal-type, spring-type element, relative to said non-local reference frame; c. a comparator for comparing the location of the user reference point relative to the non-local environment; d. a force generator for generating a signal representative of a force, based on the location of the user reference point relative to the non-local environment and a set of force rules, including spring-force rules which specify a diagonal element output force signal in response to a location signal of said user reference point indicative of a deflected conformation of said diagonal-type element; and e. a non-local environment reaction calculator that makes changes to the representation of the conformation of the non-local environment based on the signal representative of force and the set of force rules, said diagonal element spring-type rule specifying a change in the representation of the cross-sectional area of a selected region of said diagonal-type element.
Claim 9
Dependent Claim
54 words
The apparatus of claim 6, said set of force rules including a plurality of selectable different spring-force rules that specify a diagonal element output force signal, thereby facilitating a plurality of relationships between said spring-force output signal and the location of said user reference point indicative of a deflected conformation of said diagonal-type element.
Claim 10
Dependent Claim
73 words
The apparatus of claim 6 said force generator further generating forces based on the time history of the location of the user reference point relative to the non-local environment and a set of force rules, including friction-type rules which specify a friction output force signal in response to the time history of the location signal of said user reference point indicative of a change in position over time of the user reference point.
Claim 11
Dependent Claim
24 words
The apparatus of claim 6, said non-local environment further comprising an indicia of the cross-sectional area of said selected region of said diagonal-type element.
Claim 12
Dependent Claim
32 words
The apparatus of claim 9, said geometrical model residence further comprising means for storing a representation of said indicia of the cross-sectional area of said diagonal-type element as it changes over time.
Claim 13
Independent Claim
195 words
A method for generating a signal representative of force, said method comprising the steps of: a. receiving a signal representative of the location of a user reference point relative to a user reference frame; b. storing a representation of: i. a non-local reference frame; ii. the user reference frame, relative to said non-local reference frame; and iii. the conformation of a, non-local environment comprising a diagonal-type, spring-type element, relative to said non-local reference frame; c. comparing the location of the user reference point relative to the non-local environment; and d. generating a signal representative of a force, based on the location of the user reference point relative to the non-local environment and a set of force rules, including spring-force rules which specify a diagonal element output force signal in response to a location signal of said user reference point indicative of a deflected conformation of said diagonal-type element; e. changing the representation of the conformation of the non-local environment based on the signal representative of force and the set of force rules, said diagonal element spring-type rule specifying a change in the representation of the cross-sectional area of a selected region of said diagonal-type element.
Claim 14
Independent Claim
195 words
A method for generating a signal representative of force, said method comprising the steps of: a. receiving a signal representative of the location of a user reference point relative to a user reference frame; b. storing a representation of: i. a non-local reference frame; ii. the user reference frame, relative to said non-local reference frame; and iii. the conformation of a, non-local environment comprising a diagonal-type, spring-type element, relative to said non-local reference frame; c. comparing the location of the user reference point relative to the non-local environment; and d. generating a signal representative of a force, based on the location of the user reference point relative to the non-local environment and a set of force rules, including spring-force rules which specify a diagonal element output force signal in response to a location signal of said user reference point indicative of a deflected conformation of said diagonal-type element; e. changing the representation of the conformation of the non-local environment based on the signal representative of force and the set of force rules, said diagonal element spring-type rule specifying a change in the representation of the cross-sectional area of a selected region of said diagonal-type element.
Claim 15
Dependent Claim
32 words
The method of claim 11, further comprising the step of maintaining in said representation of said non-local environment an indicia of the cross-sectional area of said selected region of said diagonal-type element.
Claim 16
Dependent Claim
29 words
The method of claim 12, further comprising the step of storing a representation of said indicia of the cross-sectional area of said diagonal-type element as it changes over time.
Claim 17
Dependent Claim
33 words
The method of claim 13, further comprising the step of displaying said representation of said indicia of the cross-sectional area of said diagonal-type element as it changes over time on a visual display.
Claim 18
Independent Claim
98 words
An apparatus for physically exchanging a force with a user in a user-local environment, comprising: a user connection element; and a linkage physically linking said user connection element to a reference, said linkage providing at least six independent degrees of freedom to said user connection element, said linkage comprising: an actuator system powering at least three of the at least six independent degrees of freedom of said user connection element relative to the reference; wherein at least three of the at least six independent degrees of freedom of said user connection element are free-of-power relative to the reference.
Claim 19
Independent Claim
98 words
An apparatus for physically exchanging a force with a user in a user-local environment, comprising: a user connection element; and a linkage physically linking said user connection element to a reference, said linkage providing at least six independent degrees of freedom to said user connection element, said linkage comprising: an actuator system powering at least three of the at least six independent degrees of freedom of said user connection element relative to the reference; wherein at least three of the at least six independent degrees of freedom of said user connection element are free-of-power relative to the reference.
Claim 20
Dependent Claim
16 words
The apparatus of claim 15 wherein said linkage further comprises at least two linked orthogonal bearings.
Claim 21
Dependent Claim
35 words
The apparatus of claim 15 wherein said linkage further comprises a sensor determining a position of said user connection element relative to the reference with respect to the at least three powered degrees of freedom.
Claim 22
Dependent Claim
24 words
The apparatus of claim 15 wherein said user connection element is capable of exchanging an attractive force and a repulsive force with a user.
Claim 23
Dependent Claim
35 words
The apparatus of claim 15 wherein said actuator system further comprises at least one ironless armature motor powering at least one of the at least three powered degrees of freedom of said user connection element.
Claim 24
Dependent Claim
73 words
The apparatus of claim 15 wherein said linkage further comprises a plurality of interconnected links, at least one of the plurality of interconnected links being mechanically coupled to said user connection element and wherein said actuator system further comprises: at least one ironless armature motor powering at least one of the at least three powered independent degrees of freedom; and a cable transmission mechanically coupling said motor to said plurality of interconnected links.
Claim 25
Dependent Claim
15 words
The apparatus of claim 15 wherein the reference is a portion of the user's body.
Claim 26
Dependent Claim
53 words
The apparatus of claim 15 wherein said linkage further comprises a link and wherein said actuator system further comprises a pair of actuators more distal to the reference than said link, each actuator being connected to said link through a cable and being movable relative to each other and relative to said link.
Claim 27
Dependent Claim
43 words
The apparatus of claim 15 wherein said actuator system further comprises: an actuator powering at least one of the at least three powered independent degrees of freedom of said user connection element; and a cable transmission mechanically coupling said actuator to said linkage.
Claim 28
Dependent Claim
43 words
The apparatus of claim 15 wherein said actuator system receives a non-local signal from a non-local environment and powers the at least three powered independent degrees of freedom of said user connection element relative to the reference in response to the non-local signal.
Claim 29
Dependent Claim
42 words
The apparatus of claim 24 wherein said linkage further comprises a sensor tracking the at least three powered degrees of freedom and sending a master signal to the non-local environment in response to the tracked at least three powered degrees of freedom.
Claim 30
Dependent Claim
39 words
The apparatus of claim 15 wherein said linkage further comprises a sensor determining a position of said user connection element relative to the reference with respect to at least one of the at least three free-of-power degrees of freedom.
Claim 31
Dependent Claim
40 words
The apparatus of claim 26 wherein said actuator system powers the at least three powered degrees of freedom in response to the position of said user connection element with respect to the at least one sensed free-of-power degree of freedom.
Claim 32
Dependent Claim
65 words
The apparatus of claim 15 wherein said linkage further comprises at least two masses that are movable relative to the reference, movable relative to each other and movable relative to said user connection element such that the center of mass among said at least two masses and said user connection element remains substantially stationary relative to the reference despite motion of said user connection element.
Claim 33
Dependent Claim
17 words
The apparatus of claim 28 wherein at least one of said at least two masses comprises actuator.
Claim 34
Dependent Claim
72 words
The apparatus of claim 15 wherein said linkage further comprises a plurality of interconnected links, at least one of the plurality of interconnected links being mechanically coupled to said user connection element, and wherein said actuator system further comprises: an actuator powering at least one of the three powered degrees of freedom of said user connection element; and a flexible transmission member mechanically coupling said actuator to said plurality of interconnected links.
Claim 35
Dependent Claim
13 words
The apparatus of claim 30 wherein said actuator is an ironless armature motor.
Claim 36
Dependent Claim
48 words
The apparatus of claim 30 wherein said actuator comprises a motor having a capstan with an exterior surface, the exterior surface having a groove extending at least a portion of the circumference of said capstan, wherein said groove is sized and shaped to engage said flexible transmission member.
Claim 37
Dependent Claim
51 words
The apparatus of claim 30 wherein said actuator system comprises a motor having a capstan, and wherein said flexible transmission member extends along at least a portion of a perimeter of one of said plurality of interconnected links and is intracrossed forming a loop, said loop being engaged on said capstan.
Claim 38
Dependent Claim
36 words
The apparatus of claim 15 wherein said linkage further comprises first and second linked orthogonal bearings and a third bearing, which is linked to and orthogonal to one of either the first or second linked bearings.
Claim 39
Dependent Claim
31 words
The apparatus of claim 34 wherein each of said first, second and third bearings has an axis of rotation, each of the axes of rotation coinciding at a user reference point.
Claim 40
Dependent Claim
44 words
The apparatus of claim 35 wherein said user connection element comprises a thimble into which a body member of the user may be inserted, said thimble being arranged such that the user reference point is within the body member when inserted into said thimble.
Claim 41
Independent Claim
101 words
An apparatus for physically exchanging a force with a user in a user-local environment, comprising: a user connection element comprising a rod; and a linkage physically linking said user connection element to a reference, said linkage providing at least four independent degrees of freedom to said user connection element, said linkage comprising: an actuator system powering at least three of the at least four independent degrees of freedom of said user connection element relative to the reference; wherein at least one of the at least four independent degrees of freedom of said user connection element is free-of-power relative to the reference.
Claim 42
Independent Claim
101 words
An apparatus for physically exchanging a force with a user in a user-local environment, comprising: a user connection element comprising a rod; and a linkage physically linking said user connection element to a reference, said linkage providing at least four independent degrees of freedom to said user connection element, said linkage comprising: an actuator system powering at least three of the at least four independent degrees of freedom of said user connection element relative to the reference; wherein at least one of the at least four independent degrees of freedom of said user connection element is free-of-power relative to the reference.
Claim 43
Dependent Claim
35 words
The apparatus of claim 37 wherein said actuator system further comprises at least one ironless armature motor powering at least one of the at least three powered degrees of freedom of said user connection element.
Claim 44
Dependent Claim
72 words
The apparatus of claim 37 wherein said linkage further comprises a plurality of interconnected links, at least one of the plurality of interconnected links being mechanically coupled to said user connection element and wherein said actuator system further comprises: at least one ironless armature motor powering at least one of the at least three powered degrees of freedom; and a cable transmission mechanically coupling said motor to said plurality of interconnected links.
Claim 45
Dependent Claim
15 words
The apparatus of claim 37 wherein the reference is a portion of the user's body.
Claim 46
Dependent Claim
42 words
The apparatus of claim 37 wherein said actuator system further comprises: an actuator powering at least one of the at least four independent degrees of freedom of said user connection element; and a cable transmission mechanically coupling said actuator to said linkage.
Claim 47
Dependent Claim
35 words
The apparatus of claim 37 wherein said linkage further comprises a sensor determining a position of said user connection element relative to the reference with respect to the at least one free-of-power degree of freedom.
Claim 48
Dependent Claim
39 words
The apparatus of claim 42 wherein said actuator system powers the at least three powered degrees of freedom in response to the position of said user connection element with respect to the at least one free-of-power degree of freedom.
Claim 49
Dependent Claim
72 words
The apparatus of claim 37 wherein said linkage further comprises a plurality of interconnected links, at least one of the plurality of interconnected links being mechanically coupled to said user connection element, and wherein said actuator system further comprises: an actuator powering at least one of the three powered degrees of freedom of said user connection element; and a flexible transmission member mechanically coupling said actuator to said plurality of interconnected links.
Claim 50
Dependent Claim
51 words
The apparatus of claim 44 wherein said actuator system comprises a motor having a capstan, and wherein said flexible transmission member extends along at least a portion of a perimeter of one of said plurality of interconnected links and is intracrossed forming a loop, said loop being engaged on said capstan.
Claim 51
Independent Claim
101 words
An apparatus for physically exchanging a force with a user in a user-local environment, comprising: a user connection element comprising a rod; and a linkage physically linking said user connection element to a reference, said linkage providing at least five independent degrees of freedom to said user connection element, said linkage comprising: an actuator system powering at least three of the at least five independent degrees of freedom of said user connection element relative to the reference; wherein at least two of the at least five independent degrees of freedom of said user connection element are free-of-power relative to the reference.
Claim 52
Independent Claim
101 words
An apparatus for physically exchanging a force with a user in a user-local environment, comprising: a user connection element comprising a rod; and a linkage physically linking said user connection element to a reference, said linkage providing at least five independent degrees of freedom to said user connection element, said linkage comprising: an actuator system powering at least three of the at least five independent degrees of freedom of said user connection element relative to the reference; wherein at least two of the at least five independent degrees of freedom of said user connection element are free-of-power relative to the reference.
Claim 53
Independent Claim
101 words
An apparatus for physically exchanging a force with a user in a user-local environment comprising: a user connection element comprising a rod; and a linkage physically linking said user connection element to a reference, said linkage providing at least five independent degrees of freedom to said user connection element, said linkage comprising: an actuator system powering at least four of the at least five independent degrees of freedom of said user connection element relative to the reference; wherein at least one of the at least five independent degrees of freedom of said user connection element are free-of-power relative to the reference.
Claim 54
Independent Claim
101 words
An apparatus for physically exchanging a force with a user in a user-local environment comprising: a user connection element comprising a rod; and a linkage physically linking said user connection element to a reference, said linkage providing at least five independent degrees of freedom to said user connection element, said linkage comprising: an actuator system powering at least four of the at least five independent degrees of freedom of said user connection element relative to the reference; wherein at least one of the at least five independent degrees of freedom of said user connection element are free-of-power relative to the reference.
Claim 55
Independent Claim
101 words
An apparatus for physically exchanging a force with a user in a user-local environment, comprising: a user connection element comprising a rod; and a linkage physically linking said user connection element to a reference, said linkage providing at least six independent degrees of freedom to said user connection element, said linkage comprising: an actuator system powering at least five of the at least six independent degrees of freedom of said user connection element relative to the reference; wherein at least one of the at least six independent degrees of freedom of said user connection element are free-of-power relative to the reference.
Claim 56
Independent Claim
101 words
An apparatus for physically exchanging a force with a user in a user-local environment, comprising: a user connection element comprising a rod; and a linkage physically linking said user connection element to a reference, said linkage providing at least six independent degrees of freedom to said user connection element, said linkage comprising: an actuator system powering at least five of the at least six independent degrees of freedom of said user connection element relative to the reference; wherein at least one of the at least six independent degrees of freedom of said user connection element are free-of-power relative to the reference.
Claim 57
Independent Claim
137 words
A method for physically exchanging a force between an apparatus and a user in a user-local environment, comprising the steps of: a. providing an apparatus comprising: i. a user connection element; and ii. a linkage physically linking said user connection element to a reference, said linkage providing at least six independent degrees of freedom to said user connection element, said linkage comprising: an actuator system powering at least three of the at least six independent degrees of freedom of said user connection element relative to the reference, three of the at least six independent degrees of freedom remaining free-of-power relative to the reference; b. connecting said user connection element to a body member of a user; and c. powering the at least three of the at least six independent degrees of freedom of said user connection element.
Claim 58
Independent Claim
137 words
A method for physically exchanging a force between an apparatus and a user in a user-local environment, comprising the steps of: a. providing an apparatus comprising: i. a user connection element; and ii. a linkage physically linking said user connection element to a reference, said linkage providing at least six independent degrees of freedom to said user connection element, said linkage comprising: an actuator system powering at least three of the at least six independent degrees of freedom of said user connection element relative to the reference, three of the at least six independent degrees of freedom remaining free-of-power relative to the reference; b. connecting said user connection element to a body member of a user; and c. powering the at least three of the at least six independent degrees of freedom of said user connection element.
Claim 59
Dependent Claim
56 words
The method of claim 49 wherein the step of powering the at least three of the at least six independent degrees of freedom further comprises the step of generating a signal in a non-local environment and powering the at least three of the at least six independent degrees of freedom in response to the non-local signal.
Claim 60
Independent Claim
106 words
An apparatus for physically exchanging a force with a user in a user-local environment comprising: a user connection element; and a linkage physically linking said user connection element to a reference, said linkage providing at least two independent degrees of freedom to said user connection element, said linkage comprising: an actuator system comprising an ironless armature motor, said actuator system powering at least one of the at least two independent degrees of freedom of said user connection element relative to the reference, wherein at least one of the at least two independent degrees of freedom of said user connection element is free-of-power relative to the reference.
Claim 61
Independent Claim
106 words
An apparatus for physically exchanging a force with a user in a user-local environment comprising: a user connection element; and a linkage physically linking said user connection element to a reference, said linkage providing at least two independent degrees of freedom to said user connection element, said linkage comprising: an actuator system comprising an ironless armature motor, said actuator system powering at least one of the at least two independent degrees of freedom of said user connection element relative to the reference, wherein at least one of the at least two independent degrees of freedom of said user connection element is free-of-power relative to the reference.
Claim 62
Dependent Claim
71 words
The apparatus of claim 51, wherein said motor has a capstan and wherein said linkage further comprises: a plurality of interconnected links; and a flexible transmission member mechanically coupling said capstan to said plurality of interconnecting links, said flexible transmission member extending along at least a portion of a perimeter of one of said plurality of interconnected links and being intracrossed forming a loop, said loop being engaged on said capstan.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-04-26 | 2002-10-26 | 2003-04-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-04-26 | 2006-10-26 | 2007-04-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-04-26 | 2010-10-26 | 2011-04-27 | $7700.00 | Window Closed / Lapsed |