Hierarchical methods for generating force feedback effects

• US 20040217942A1
• Filed: 04/30/2003
• Published: 11/04/2004
• Est. Priority Date: 04/30/2003
• Status: Active Grant

• Current Assignee: Immersion Corporation
• Original Assignee: Immersion Corporation
• Inventors: Grant, Danny
• Granted Patent: US 7,280,095 B2
• Time in Patent Office: Days
• US Class Current: 345/161
• CPC Class Codes: G06F 3/016 Input arrangements with force or tactile feedback as computer generated output to the user

Abstract

Embodiments of the invention relate to a hierarchical method for generating force feedback effects. In one embodiment, a method comprises receiving a first force contribution associated with a first (e.g., previous) position of a manipulandum; determining a second force contribution associated with a second (e.g., current) position of the manipulandum; and outputting a force signal to an actuator coupled to the manipulandum, such that the actuator renders a feedback force having a sum of the first and second force contributions. The method may further include classifying force effects according to a predetermined “hierarchy” (or “priority”) scheme, whereby the second force contribution is related to “high” priority force effects associated with the second position, and the first force contribution is related to “low” priority force effects associated with the first position. As such, computation delay in outputting force feedback effects can be substantially reduced, thereby enhancing the stability and performance of the underlying force feedback system.

Claims

1. A method, comprising:

receiving a force contribution associated with a first position of a manipulandum;

determining a force contribution associated with a second position of the manipulandum, the second position being subsequent to the first position; and

outputting a force signal to an actuator coupled to the manipulandum, the actuator configured to render a feedback force having a sum of the force contribution associated with the first position and the force contribution associated with the second position.

2. The method of claim 1, further comprising:

classifying a plurality of force effects according to a priority scheme, the force contribution associated with the first position including at least one force effect associated with the first position and associated with a first priority value, the force contribution associated with the second position including at least one force effect associated with the second position and associated with a second priority value.

3. The method of claim 2, wherein the priority scheme is associated with a system stability.

4. The method of claim 3, wherein the at least one force effect associated with the second priority value includes at least one condition effect, the at least one force effect associated with the first priority value includes at least one temporal effect.

5. The method of claim 2, wherein the priority scheme is associated with an effect gain.

6. The method of claim 5, wherein the at least one force effect associated with the second priority value includes at least one high gain force effect, and the at least one force effect associated with the first priority value includes at least one low gain force effect.

7. The method of claim 2, further comprising determining a third force contribution related to at least one force effect associated with the second position that is associated with the first priority value, after outputting the force signal.

8. The method of claim 1, wherein the manipulandum includes one of a knob, a scroll wheel, a steering wheel, a jog dial, a joystick, and a medical instrument.

9. A processor-executable program, stored on a computer-readable medium, comprising:

code to receive a force contribution associated with a first position of a manipulandum;

code to determine a force contribution associated with a second position of the manipulandum, the second position being subsequent to the first position; and

code to output a force signal to an actuator coupled to the manipulandum, the actuator configured to render a feedback force having a sum of the force contribution associated with the first position and the force contribution associated with the second position.

10. The processor-executable program of claim 9 further comprising:

code to classify a plurality of force effects according to a priority scheme, the force contribution associated with the first position including at least one force effect associated with the first position and associated with a first priority value, and the force contribution associated with the second position including at least one force effect associated with the second position and associated with a second priority value.

11. The processor-executable program of claim 10 further comprising:

code to determine a force contribution related to at least one force effect associated with the second position and associated with the first priority value, after execution of the code to output the force signal.

12. An apparatus, comprising:

a manipulandum having a range of motion including a first position and a second position;

a sensor coupled to the manipulandum and operable to monitor a position of the manipulandum in the range of motion; and

an actuator coupled to the manipulandum, the actuator configured to receive a force signal and output a feedback force having a first force contribution and a second force contribution, the first force contribution associated with the first position of the manipulandum, the second force contribution being associated with the second position of the manipulandum.

13. The apparatus of claim 12 wherein the second position is subsequent to the first position, a plurality of force effects have an associated priority value according to a priority scheme, the first force contribution including at least one force effect associated with the first position and associated with a first priority value, and the second force contribution including at least one force effect associated with the second position and associated with a second priority value.

14. The apparatus of claim 13 wherein the at least one force effect associated with the second priority value includes at least one condition effect, and the at least one force effect associated with the first priority value includes at least one temporal effect.

15. The apparatus of claim 12 further comprising:

a processor, in communication with the sensor and the actuator, the processor operative to receive a signal from the sensor and output the force signal to the actuator.

16. The apparatus of claim 15 further comprising a memory storing a program executable by the processor, the program comprising:

code to receive the first force contribution associated with the first position of the manipulandum;

code to determine the second force contribution associated with the second position of the manipulandum, the second position being subsequent to the first position; and

code to output the force signal to the actuator coupled to the manipulandum.

17. The apparatus of claim 12 wherein the manipulandum includes one of a knob, a scroll wheel, a steering wheel, a jog dial, a joystick, and a medical instrument.