Virtual environment tactile system

• US 5,583,478 A
• Filed: 03/01/1995
• Issued: 12/10/1996
• Est. Priority Date: 03/01/1995
• Status: Expired due to Fees

• Current Assignee: Sandia National Laboratories (Government of the United States of America)
• Original Assignee: Sandia National Laboratories (Government of the United States of America)
• Inventors: Renzi, Ronald
• Primary Examiner(s): Hofsass, Jeffery
• Assistant Examiner(s): TRIEU, VAN THANH
• Application Number:
  US08/397,291
• Time in Patent Office: 650 Days
• Field of Search: 340/407.1, 340/407.2, 340/825.19, 340/965, 73/862.04, 73/865.7, 434/112, 434/113, 434/114, 434/115, 414/4, 414/5, 414/6, 414/7, 341/20, 341/21, 341/27
• US Class Current: 340/407.1
• CPC Class Codes: G06F 3/011 Arrangements for interaction with the human body, e.g. for user immersion in virtual reality blind teaching G09B21/00
• CPC Class Codes: G06F 3/014 Hand-worn input/output arrangements, e.g. data gloves
• CPC Class Codes: G06F 3/016 Input arrangements with force or tactile feedback as computer generated output to the user

Abstract

A method for providing a realistic sense of touch in virtual reality by means of programmable actuator assemblies is disclosed. Each tactile actuator assembly consists of a number of individual actuators whose movement is controlled by a computer and associated drive electronics. When an actuator is energized, the rare earth magnet and the associated contactor, incorporated within the actuator, are set in motion by the opposing electromagnetic field of a surrounding coil. The magnet pushes the contactor forward to contact the skin resulting in the sensation of touch. When the electromagnetic field is turned off, the rare earth magnet and the contactor return to their neutral positions due to the magnetic equilibrium caused by the interaction with the ferrous outer sleeve. The small size and flexible nature of the actuator assemblies permit incorporation into a glove, boot or body suit. The actuator has additional applications, such as, for example, as an accelerometer, an actuator for precisely controlled actuations or to simulate the sensation of braille letters.

Claims

1. A system for providing a sense of touch on a sensing area of a user'"'"'s skin by converting electrical signals from a controller to tactile sensations produced by an actuator assembly, the actuator assembly comprising:

a) a plurality of individually addressable actuators for contacting the sensing area of the user'"'"'s skin, wherein the plurality of individually addressable actuators is arranged in a matrix, each actuator including;

1) a nonferrous spool having an axial cavity, wherein the cavity has one open end,

2) a magnet slidably disposed within the cavity,

3) a contactor adjacent the magnet, and

4) a coil wrapped around the nonferrous spool such that the magnet is at least partially within the circumference of the coil,

b) a sleeve disposed around the nonferrous spool, wherein the sleeve encloses the nonferrous spool and the coil disposed thereon and isolates a magnetic field produced by the coil when the coil is energized by an electrical signal such that the magnetic field remains substantially within the nonferrous spool and sleeve; and

c) a flexible enclosure housing the matrix of actuators and providing for coupling the electrical signals received from the controller to at least one of the actuators in the actuator assembly, wherein the flexible enclosure conforms substantially to a contour of the area of the user'"'"'s skin.

2. The system of claim 1, wherein the individually addressable actuators have an operating bandwidth of less than about 300 Hz.

3. The system of claim 1, wherein the sleeve is comprised of a ferrous material.

4. The system of claim 1, wherein the magnet is selected from the group consisting of Samarium-Cobalt, Neodymium and rare earth magnet materials and combinations thereof.

5. The system of claim 1, wherein the nonferrous spool is elected from the group consisting of lucite, delrin and lexan and combinations thereof.

6. The system of claim 1, wherein the flexible enclosure further comprises:

a) a flexible printed circuit having a plurality of wiring path pairs, at least one for each actuator, wherein each wiring path pair is coupled to the coil in each actuators; and

b) a flexible structure holding the matrix of actuators in place and being bonded to the flexible printed circuit.

12. The apparatus of claim 4, wherein the controller comprises a processor and waveform generator, wherein the processor provides at least one of wave type, frequency, phase and amplitude to the waveform generator and the waveform generator outputs a unique waveform to each coil within each of the tactile actuators in all of the actuator assemblies.

7. A system for providing a sensation of touch to a user, wherein electrical signals are transmitted to a glove worn by the user, the glove comprising:

a) a plurality of matrices of actuators being disposed in the glove, wherein each actuator in each of said matrices of actuators is individually addressable, and wherein each actuator includes;

i) a nonferrous spool having an axial cavity, wherein the cavity has one open end,

ii) a magnet slidably disposed within the cavity,

iii) a contactor adjacent the magnet, and

iv) a coil wrapped around the nonferrous spool such that the magnet is at least partially within the circumference of the coil,

b) a sleeve disposed around the nonferrous spool, wherein the sleeve encloses the nonferrous spool and the coil disposed thereon and isolates a magnetic field produced by the coil when the coil is energized by an electrical signal such that the magnetic field remains substantially within the nonferrous spool and sleeve; and

c) a plurality of wires being disposed in the glove, one pair of wires for each actuator, each of the wire pairs transmitting an electrical signal to at least one of the actuators, thereby energizing the coil in said one actuator and causing the contactor to contact the user'"'"'s skin.

8. The system according to claim 7, wherein the electrical signals energize each coil in each actuator independently of all other coils, thereby simulating a sense of touch.

9. The system of claim 7, further comprising one matrix of actuators being disposed in an index finger of the glove, one matrix of actuators being disposed in a thumb of the glove, and one matrix of actuators being disposed in a middle finger of the glove.

10. The system of claim 9, further comprising one of the matrix of actuators being disposed in a palm region of the glove.

11. An apparatus for providing a sense of touch to a user, comprising:

a) a plurality of tactile actuator assemblies, one for a different area of the user'"'"'s skin, each tactile actuator assembly including;

i) a matrix of tactile actuators, each tactile actuator including;

1) a nonferrous spool having an axial cavity, wherein the cavity has one open end,

2) a magnet slidably disposed within the cavity,

3) a contactor adjacent the magnet,

4) a coil wrapped around the nonferrous spool such that the magnet is at least partially within the circumference of the coil, and

5) a sleeve disposed around the nonferrous spool, wherein the sleeve encloses the nonferrous spool and the coil disposed thereon and isolates a magnetic field produced by the coil when the coil is energized by an electrical signal such that the magnetic field remains substantially within the nonferrous spool and sleeve,

ii) a flexible enclosure conforming substantially to the area of the user'"'"'s skin and housing the matrix of tactile actuators and including a plurality of wire pairs, at least one pair for each of the tactile actuators, each of said one wire pairs being coupled to the coil in one of the tactile actuators in the matrix of tactile actuators such that each actuator is individually addressable; and

b) a controller coupled to each tactile actuator and transmitting electrical control signals to each tactile actuator, which electrical control signals control the frequency and amplitude of movement of all of the contactors in all of the tactile actuators independently of each other.

13. A method of providing a sensation of touch to a user, comprising the steps of:

a) specifying a waveform for each of a plurality of electrical control signals;

b) controlling the movement of a plurality of magnets disposed near the skin of the user by energizing a plurality of coils with the plurality of electrical control signals; and

c) contacting the skin of the user with a plurality of contactors being driven by a plurality of magnets.

14. The method of claim 13, further comprising the steps of;

d) disposing a plurality of actuators on the skin of the user, wherein each actuator includes;

i) a nonferrous spool having an axial cavity, wherein the cavity has one open end,

ii) a magnet slidably disposed within the cavity,

iii) a contactor adjacent the magnet,

iv) a coil wrapped around the nonferrous spool such that the magnet is at least partially within the circumference of the coil, and

v) a sleeve disposed around the nonferrous spool, wherein the sleeve encloses the nonferrous spool and the coil disposed thereon and isolates a magnetic field produced by the coil when the coil is energized by an electrical signal such that the magnetic field remains substantially within the nonferrous spool and sleeve,

e) transmitting at least one electrical control signal to the coil in at least one of the actuators; and

f) contacting the user'"'"'s skin with the contactor in said one actuator as a function of said one electrical control signal.

15. The method of claim 13, wherein the step of specifying further comprises specifying at least one of frequency, amplitude, phase and waveform type for each electrical control signal, and wherein the step of contacting further comprises contacting the user'"'"'s skin according to the frequency, amplitude, phase and waveform type of the electrical control signal.