CONTROLLING A USER'S TACTILE PERCEPTION IN A DYNAMIC PHYSICAL ENVIRONMENT

• US 20140139327A1
• Filed: 11/19/2012
• Published: 05/22/2014
• Est. Priority Date: 11/19/2012
• Status: Active Grant

• Current Assignee: Disney Enterprises Incorporated (The Walt Disney Company)
• Original Assignee: Disney Enterprises Incorporated (The Walt Disney Company)
• Inventors: Bau, Olivier, Poupyrev, Ivan, LeGoc, Mathieu
• Granted Patent: US 9,122,330 B2
• Time in Patent Office: Days
• US Class Current: 340/407.1
• CPC Class Codes: G06F 3/016 Input arrangements with force or tactile feedback as computer generated output to the user
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/0425 using a single imaging device like a video camera for tracking the absolute position of a single or a plurality of objects with respect to an imaged reference surface, e.g. video camera imaging a display or a projection screen, a table or a wall surface, on which a computer generated image is displayed or projected tracking a projected light spot to determine a position on a display surface G06F3/0386
• CPC Class Codes: G06F 3/0488 using a touch-screen or digitiser, e.g. input of commands through traced gestures

Abstract

To maintain consistency in different environments with different impedances, a high voltage current driver may be used as a signal generator to output a tactile signal with a constant current. The constant current ensures that the voltage between the user'"'"'s finger and the object'"'"'s surface or electrode remains the same even if impedances in the electrical path change. Specifically, the current driver includes a current sensing circuit that determines the average current being generated. Using a feedback loop, the measured current is compared to a reference current to determine if the correct tactile sensation is perceived by the user. As the impedance changes, the current driver detects the resulting change in the signal'"'"'s current and adjusts the voltage amplitude of the generated tactile signal in order to match the measured current to the reference current.

Claims

1. A method, comprising:

generating an electrical signal in a first electrical path, the electrical signal causing a user to perceive a tactile sensation as a contact surface of the first electrical path is urged by the user along a surface of the object;

measuring a current of the electrical signal; and

adjusting at least one characteristic of the electrical signal based on the measured current to generate a predetermined tactile sensation at the appendage.

2. The method of claim 1, further comprising:

comparing the measured current to a reference current associated with the predetermined tactile sensation, wherein adjusting the characteristic of the electrical signal alters a current of the electrical path to substantially match the reference current.

3. The method of claim 1, wherein the at least one characteristic is a voltage amplitude of the electrical signal, and wherein the contact surface of the first electrical path is at least one of an appendage of the user and a conductive element held by the user.

4. The method of claim 1, wherein the object comprises a conductive layer and an insulator layer, wherein at least a portion of the conductive layer is covered by the insulator layer.

5. The method of claim 4, wherein the conductive layer is coupled to a same electrical reference point as the signal generator.

6. The method of claim 1, further comprising:

receiving an instruction from a motion detection system tracking a location of an appendage of the user or a conductive element held by the user on the surface of the object, wherein at least one characteristic of the electrical signal is defined based on the instruction.

7. The method of claim 1, further comprising, after adjusting at least one characteristic of the electrical signal:

generating the electrical signal when an appendage of the user or a conductive element held by the user touches a different object, thereby creating a second electrical path comprising a different net impedance relative to a net impedance of the first electrical path,

measuring the current of the electrical signal in the second electrical path, and

adjusting at least one characteristic of the electrical signal based on the measured current in the second electrical path to produce a same tactile sensation at the appendage that was produced using the first electrical path.

8. A signal generator, comprising:

a tactile signal module configured to generate an electrical signal in a electrical path, the electrical signal causing a user to perceive a tactile sensation as a contact surface of the electrical path is urged by the user along a surface of the object;

a current sensing circuit configured to measure a current of the electrical signal; and

a feedback loop configured to transmit the measured current to the tactile signal module, wherein the tactile signal module is configured to adjust at least one characteristic of the electrical signal based on the measured current to generate a predetermined tactile sensation at the user.

9. The signal generator of claim 8, wherein the tactile signal module is configured to compare the measured current to a reference current associated with the predetermined tactile sensation and adjust the characteristic of the electrical signal and alter a current of the electrical path to substantially match the reference current.

10. The signal generator of claim 8, further comprising:

a first electrical interface configured to introduce the electrical signal to the user'"'"'s body; and

a second electrical interface configured to couple the signal generator to a electrical reference point shared with the object.

11. The signal generator of claim 8, wherein the tactile signal module is configured to alter a voltage amplitude of the electrical signal based on the measured current, wherein the contact surface is at least one of an appendage of the user and a conductive element held by the user.

12. The signal generator of claim 8, further comprising:

a wireless receiver configured to receive an instruction from a motion detection system tracking a location of an appendage of the user or a conductive element held by the user on the surface of the object, wherein at least one characteristic of the electrical signal is defined based on the instruction.

13. The signal generator of claim 8, wherein the tactile signal module is configured to generate a detection signal when the measured current falls below a predefined current threshold, wherein the detection signal uses less power than the electrical signal that produces the tactile sensation.

14. The signal generator of claim 8, further comprising a battery configured to power the tactile signal module.

15. A system, comprising:

a first object; and

a first signal generator configured to generate a first electrical signal in a first electrical path, the first electrical signal causing a first user to perceive a tactile sensation as a first contact surface of the first electrical path is urged by the first user along a surface of the first object,

wherein the first signal generator is configured to measure a current of the first electrical signal,

wherein the first signal generator is configured to transmit the measured current to the tactile signal module, and wherein the tactile signal module is configured to adjust at least one characteristic of the first electrical signal based on the measured current to generate a predetermined tactile sensation at the user.

16. The system of claim 15, further comprising a second signal generator configured to generate a second, different electrical signal in a second electrical path, the second electrical signal causing a second user to perceive a different tactile sensation relative to the tactile sensation perceived by the first user as a second contact surface of the second electrical path is urged by the second user along the surface of the first object,

wherein the first and second contact surfaces of the first and second electrical paths contact the surface of the first object simultaneously.

17. The system of claim 15, wherein the first object comprises a conductive layer and an insulator layer, wherein at least a portion of the conductive layer is covered by the insulator layer, and

wherein the conductive layer and the first signal generator are coupled to a same electrical reference.

18. The system of claim 15, further comprising:

a second object,

wherein the first signal generator is configured to generate the first electrical signal when the first user contacts the second object, thereby creating a second electrical path comprising a different net impedance relative to a net impedance of the first electrical path,

wherein the first signal generator is configured to measure the current of the first electrical signal in the second electrical path, and adjust at least one characteristic of the first electrical signal based on the measured current in the second electrical path to produce a same tactile sensation at the first user that was produced using the first electrical path.

19. The system of claim 15, further comprising a tracking module configured to track the movement of the contact surface on the surface of the first object and transmit, based on a location, an instruction to the signal generator controlling when the signal generator generates the electric signal.

20. The system of claim 19, wherein the tracking module is configured to transmit a first instruction when contact surface is at a first location on the surface of the first object and a second instruction when the contact surface is at a second location on the surface of the first object, the first instruction causing the signal generator to generate a different electric signal relative to the electric signal generated in response to the second instruction.

21. A signal generator, comprising:

a tactile signal component configured to generate an electrical signal indicative of a tactile characteristic of an object, wherein an electrical path including the tactile signal component and the object exhibits impedance variations; and

a compensation component configured to adjust the electrical signal to compensate for the impedance variations to produce a compensated electrical signal, wherein the compensated electrical signal is coupled to a user such that the compensated electrical signal causes the user to perceive a substantially consistent tactile sensation during the exhibited impedance variations.