US6147422A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Actuator with opposing repulsive magnetic forces
Assignee: Coactive Drive Corp
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Filing: 1999-07-09
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Granted: 2000-11-14
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Expires: 2019-07-09
Abstract
Abstract A new class of actuators and mechanisms use opposing repulsive magnetic forces. The repulsive forces are typically generated between a stationary magnet and a moving magnet, where the moving magnet is coupled to the mechanism output member. The mechanisms are generally configured such that the repulsive force from one electromagnet is opposed by a repulsive force from another electromagnet, where the opposing forces are simultaneously applied to the mechanism's output member. This configuration is similar in certain aspects to the way biological flexor and extensor muscles are configured in a musculoskeletal system. The opposing configuration allows for open loop control of position and stiffness. The actuator mechanism may have both rotary and linear motion output, and may have either a single degree of freedom or multiple degrees of freedom. Permanent magnets can be used to create a baseline repulsive force without electric power, and electromagnets can modulate the repulsive force magnitude. The actuator can provide high fidelity motion and force output, and is well suited for human interface devices, such as force feedback joysticks. Other applications include adjustable stiffness devices, and high bandwidth mechanisms.
Inventors
- 👤 Nathan J. Delson
- 👤 John S Houston
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 21:40
CPC Classifications
H; H02; H02K; H02K26/00; H02K23/00; H02K41/00; H02K41/02; H02K41/035; H02K41/0352; H02K2201/00; H02K2201/18
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
86 words
An actuator assembly comprising: a. an interface member, constrained by a travel guide to have between one and six DOF of motion; b. a set of force generators, each being arranged to apply a force onto said interface member; and c. a set of actuators, each actuator of said set also being arranged to apply a force onto said interface member, the force of each actuator being generated by repulsive magnetic forces, each actuator being in opposition with at least one other actuator or force generator.
Claim 2
Dependent Claim
86 words
An actuator assembly comprising: a. an interface member, constrained by a travel guide to have between one and six DOF of motion; b. a set of force generators, each being arranged to apply a force onto said interface member; and c. a set of actuators, each actuator of said set also being arranged to apply a force onto said interface member, the force of each actuator being generated by repulsive magnetic forces, each actuator being in opposition with at least one other actuator or force generator.
Claim 3
Dependent Claim
23 words
The actuator assembly of claim 1, said interface member comprising an interface member constrained to have between two and six DOF of motion.
Claim 4
Dependent Claim
23 words
The actuator assembly of claim 2, said interface member comprising an interface member constrained to have between three and six DOF of motion.
Claim 5
Dependent Claim
14 words
The actuator assembly of claim 1, the force generators comprising passive energy storage devices.
Claim 6
Dependent Claim
16 words
The actuator assembly of claim 4, one of said passive energy storage devices comprising a spring.
Claim 7
Dependent Claim
20 words
The actuator assembly of claim 4, one of said passive energy storage devices comprising a weight in a gravitational field.
Claim 8
Dependent Claim
31 words
The actuator assembly of claim 1, said interface member being movable through a number N of Degrees of Freedom equal to the total number of actuators plus force generators minus one.
Claim 9
Dependent Claim
19 words
The actuator assembly of claim 1, further comprising, for each actuator of said set, an electromagnet and an amplifier.
Claim 10
Dependent Claim
21 words
The actuator assembly of claim 1, further comprising, for each actuator of said set, a separate electromagnet and a separate amplifier.
Claim 11
Dependent Claim
30 words
The actuator assembly of claim 8, further comprising, for each of said amplifiers, a lookup table from which to select current values or an algorithm processor to establish current values.
Claim 12
Dependent Claim
17 words
The actuator assembly of claim 10, said current values corresponding to set positions of the actuator assembly.
Claim 13
Dependent Claim
16 words
The actuator assembly of claim 10, said current values corresponding to stiffnesses of the actuator assembly.
Claim 14
Dependent Claim
20 words
The actuator assembly of claim 10, said current values corresponding to combinations of set positions and stiffnesses of the mechanism.
Claim 15
Dependent Claim
74 words
An actuator assembly comprising: a. an interface member, constrained by a travel guide to have between one and six DOF of motion; b. a plurality of pairs of actuators, where: i. each actuator is arranged to apply a force onto the interface member, each force being generated by repulsive magnetic force; and ii. each of said pairs of actuators being configured such that the actuators within the pair are in opposition with each other.
Claim 16
Dependent Claim
74 words
An actuator assembly comprising: a. an interface member, constrained by a travel guide to have between one and six DOF of motion; b. a plurality of pairs of actuators, where: i. each actuator is arranged to apply a force onto the interface member, each force being generated by repulsive magnetic force; and ii. each of said pairs of actuators being configured such that the actuators within the pair are in opposition with each other.
Claim 17
Dependent Claim
23 words
The actuator assembly of claim 14, said interface member comprising an interface member constrained to have between two and six DOF of motion.
Claim 18
Dependent Claim
23 words
The actuator assembly of claim 15, said interface member comprising an interface member constrained to have between three and six DOF of motion.
Claim 19
Dependent Claim
26 words
The actuator assembly of claim 14, further comprising, for each pair of actuators, a single amplifier, coupled to said pair of actuators to control the actuators.
Claim 20
Dependent Claim
49 words
The actuator assembly of claim 17, each said actuator comprising an electromagnet, each said amplifier configured such that an increase in current from the amplifier increases the repulsive force in one of the pair of actuators and decreases the repulsive force in the other actuator of the actuator pair.
Claim 21
Dependent Claim
32 words
The actuator assembly of claim 17, each said actuator comprising an electromagnet, each said amplifier configured such that an increase in current from the amplifier changes the position of the interface member.
Claim 22
Dependent Claim
29 words
The actuator assembly of claim 18, further comprising a lookup table or an algorithm processor that specifies the current from said amplifier corresponding to an actuator assembly set position.
Claim 23
Dependent Claim
31 words
The actuator assembly of claim 18, furhter comprising a lookup table or an algorithm processor that specifies the current from said amplifier corresponding to a force applied by the actuator assembly.
Claim 24
Dependent Claim
30 words
The actuator assembly of claim 17, where said amplifier is configured such that an increase in current from the amplifier increase the repulsive force in both actuators of the pair.
Claim 25
Dependent Claim
28 words
The actuator assembly of claim 22, further comprising a lookup table or an algorithm processor that specifies the current from said amplifier corresponding to an actuator assembly stiffness.
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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) | 2003-11-14 | 2004-05-15 | 2004-11-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-11-14 | 2008-05-15 | 2008-11-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-11-14 | 2012-05-15 | 2012-11-14 | $7700.00 | Window Closed / Lapsed |