Software controlled electromyogram control systerm

• US 20060004298A1
• Filed: 06/30/2004
• Published: 01/05/2006
• Est. Priority Date: 06/30/2004
• Status: Abandoned Application

• Current Assignee: Neural Signals, Inc
• Original Assignee: Neural Signals, Inc
• Inventors: Kennedy, Philip R., Wilmink, Ronnie J. H., Andreasen, Dinal, Wright, Edward Joseph, Cheng, Yian Chuin, Wagner, Kristan R., Montricul, Richard
• Application Number:
  US10/881,923
• Publication Number:
  US 20060004298A1
• Time in Patent Office: Days
• US Class Current: 600/546
• CPC Class Codes: A61B 5/389 Electromyography [EMG]
• CPC Class Codes: A61B 5/7257 using Fourier transforms

Abstract

A system for enabling a user to exert control with bioelectrical impulses via an input from the user includes a first electromyogram interface, a computer display and a computer. The first electromyogram interface to the user is in communication with a first source of bioelectrical impulses from the user. The computer display is capable of displaying a cursor. The computer is in communication with the electromyogram interface and the computer display, and is programmed to sense a first input from the first electromyogram interface, change a first computer control attribute in response to a state change sensed in the first input, and generate a preselected cursor action in response to a change in the first computer control attribute.

Claims

1. A system for enabling a user to exert control with bioelectrical impulses via an input from the user, comprising:

a first electromyogram interface to the user in communication with a first source of bioelectrical impulses from the user;

a. a computer display capable of displaying a cursor; and

b. a computer, in communication with the electromyogram interface and the computer display, programmed to execute the following steps;

i. sense a first input from the first electromyogram interface;

change a first computer control attribute in response to a state change sensed in the first input; and

ii. generate a preselected action in response to a change in the first computer control attribute.

2. The system of claim 1, wherein the first computer control attribute comprises a cursor attribute.

3. The system of claim 1, wherein the first computer control attribute comprises a keyboard attribute.

4. The system of claim 1, wherein the first computer control attribute indicates a direction of cursor movement.

5. The system of claim 1, wherein the first computer control attribute indicates a selection between a mouse emulation input mode and a scanning input mode.

6. The system of claim 1, wherein the first computer control attribute indicates a selection between a cursor movement mode and a cursor click mode.

7. The system of claim 1, further comprising a second electromyogram interface to the user in communication with a second source of bioelectrical impulses from the user, different from the first source of bioelectrical impulses.

8. The system of claim 7, wherein the computer is programmed to execute the following steps:

a. sense a second input from the second electromyogram interface;

b. change a second computer control attribute in response to a state change sensed in the second input; and

c. generate a preselected cursor action in response to a change in the second computer control attribute.

9. The system of claim 8, wherein the first computer control attribute comprises a selection of cursor direction and wherein the second computer control attribute comprises a selection of cursor movement.

10. The system of claim 9, wherein cursor comprises an image of a first arrow and an image of a second arrow and wherein the selection of cursor direction is accomplished according to the following steps:

a. displaying the image of the first arrow pointing in a first direction on the computer display;

b. displaying the image of the second arrow pointing in a second direction, different from the first direction, on the computer display;

c. indicating a change selection of arrow from the first arrow to the second arrow or from the second arrow to the first arrow each time the first input from the first electromyogram interface is sensed; and

d. causing the cursor to move in the direction of a currently selected one of the first arrow and the second arrow when the second input from the second electromyogram interface is sensed.

11. The system of claim 10, wherein the direction of the first arrow is transverse to the direction of the second arrow.

12. The system of claim 7, further comprising a third electromyogram interface to the user in communication with a third source of bioelectrical impulses from the user, different from the first source of bioelectrical impulses and the second source of bioelectrical impulses.

13. The system of claim 12, wherein at least one of the first electromyogram interface, the second electromyogram interface or the third electromyogram interface comprises:

a. a bioelectrical impulse sensor, capable of generating a first signal when a bioelectrical impulse is asserted;

b. a piezoelectric member, capable of generating a second signal when subjected to a mechanical force corresponding to a muscle movement; and

c. a detection system, responsive to the bioelectrical impulse sensor and the piezoelectric member, that determines if the input from the user has been asserted based on the first signal and the second signal, the detection system also capable of determining if either the bioelectrical impulse sensor or the piezoelectric member is malfunctioning and, thereby determining if the input from the user has been asserted even when one of the bioelectrical impulse sensor or the piezoelectric member is malfunctioning.

14. The electromyogram interface of claim 13, in which the detection system comprises a processor that compares a current state of the first signal and the second signal to a previous state of the first signal and the second signal to determine if either of the bioelectrical impulse sensor or the piezoelectric member is malfunctioning.

15. A method of validating an electromyogram signal, comprising the steps of:

a. incrementing a counter at a first rate of a first preselected number of counts per second if the electromyogram signal has been asserted;

b. decrementing the counter at a second rate of a second preselected number of counts per second if the electromyogram signal has not been asserted and if the counter has a value not equal to zero; and

c. asserting an electromyogram state change signal if the counter has a value of not less than a predetermined threshold value, not equal to zero.

16. The method of claim 15, wherein the first rate is greater than the second rate.

17. A method of processing electromyogram information on a computer-based system that includes a computer display, comprising the steps of:

a. causing a cursor displayed on the computer display to move in response to a first assertion of an electromyogram signal;

b. displaying a sleep-mode icon on the display;

c. entering the computer-based system into a sleep-mode state when the cursor is in a position corresponding to the sleep-mode icon;

d. disabling a predetermined set of functions controlled by the computer-based system upon entering the sleep-mode state;

e. sensing a second assertion of the electromyogram signal; and

f. re-enabling the predetermined set of functions when the second assertion of the electromyogram signal indicates that a predetermined electromyogram state has been changed.

18. The method of claim 17, wherein determining if the predetermined electromyogram state has been changed is perfonned by executing a set of steps comprising:

a. incrementing a counter at a first rate of a first preselected number of counts per second if the electromyogram signal has been asserted;

b. decrementing the counter at a second rate of a second preselected number of counts per second if the electromyogram signal has not been asserted and if the counter has a value not equal to zero; and

c. asserting an electromyogram state change signal if the counter has a value of not less than a predetermined threshold value, not equal to zero.

19. The method of claim 18, wherein the first rate is greater than the second rate.

20. A method of processing electromyogram information on a computer-based system that includes a computer display, comprising the steps of:

a. causing a cursor displayed on the computer display to move in response to a first assertion of an electromyogram signal;

b. displaying a special mode icon on the display;

c. entering the computer-based system into a special mode state when the cursor is in a position corresponding to the special mode icon such that a predetermined electromyogram state change signal has been asserted; and

d. generating a special mode indication when the computer-based system has entered the special mode state.

21. The method of claim 20, further comprising determining if the predetermined electromyogram state change signal has been asserted by executing a set of steps comprising:

a. incrementing a counter at a first rate of a first preselected number of counts per second if the electromyogram signal has been asserted;

b. decrementing the counter at a second rate of a second preselected number of counts per second if the electromyogram signal has not been asserted and if the counter has a value not equal to zero; and

c. asserting an electromyogram state change signal if the counter has a value of not less than a predetermined threshold value, not equal to zero.

22. The method of claim 21, wherein the first rate is greater than the second rate.

23. The method of claim 22, wherein the special mode icon comprises an alarm mode icon and wherein the special mode state comprises an alarm state and wherein the special mode indication comprises an alarm.

24. The method of claim 22, wherein the special mode icon comprises a sleep mode icon and wherein the special mode state comprises a sleep mode state and wherein the step of generating a special mode indication comprises suppressing a predetermined set of functions until a valid termination of sleep mode is sensed.

25. A method of processing an electromyogram information from a user, comprising the steps of:

a. measuring a first electromyogram signal corresponding to a first condition from the user;

b. measuring a second electromyogram signal corresponding to a second condition from the user, the second condition contrasting with the first condition;

c. applying a fast Fourier transform to the first signal, thereby generating a first frequency domain signal;

d. applying a fast Fourier transform to the second signal, thereby generating a second frequency domain signal;

e. comparing the first frequency domain signal and the second frequency domain signal according to predefined criteria, thereby creating a filter function;

f. applying a fast Fourier transform to a real-time electromyogram signal, thereby generating a real time frequency domain signal;

g. applying the filter function to the real-time frequency domain signal, thereby generating a real-time filtered signal;

h. applying an inverse fast Fourier transform to the real-time filtered signal, thereby generating a real-time filtered time domain signal corresponding to the real-time electromyogram signal.

26. The method of claim 25, wherein the first frequency domain signal comprises a plurality of first frequency components and the second frequency domain signal comprises a plurality of second frequency components, and wherein the step of comparing the first frequency domain signal and the second frequency domain signal according to predefined criteria further comprises the steps of:

a. performing a comparison of each of the first frequency components to a corresponding one of the second frequency components to determine a frequency component difference value for each comparison;

i. setting a frequency component multiplier equal to a first multiplier value if the frequency component difference value is less than a first threshold value;

ii. setting the frequency component multiplier equal to a second multiplier value, not equal to the first multiplier value, if the frequency component difference value is not less than the first threshold value, but less than a second threshold value; and

iii. setting the frequency component multiplier equal to a third multiplier value, different from the first multiplier value and the second multiplier value, if the frequency component difference value is not less than the second threshold value; and

b. defining the filter function as multiplying each frequency component of a frequency domain signal by the frequency component multiplier corresponding to the frequency component.

27. The method of claim 26, wherein the step of applying the filter function to the real-time frequency domain signal comprises multiplying each frequency component of the real-time frequency domain signal by the frequency component multiplier corresponding to the frequency component.

28. A device for interfacing an electromyogram to a computer, comprising:

a. a power supply;

b. a first electromyogram channel input;

c. a first output, capable of transmitting a signal from the first electromyogram channel input to the computer;

d. a first computer signal input, capable of receiving a data signal from the computer;

e. a first switch output; and

f. a first relay, activated by the first computer signal input, that electrically couples the power supply to the first switch output when a first signal is asserted at the first computer signal input, the first signal indicating that a bioelectrical impulse has been sensed by the first electromyogram channel input.

29. The device of claim 28, wherein the first output is compatible with a PCMCIA card.

30. The device of claim 28, further comprising

a. a second electromyogram channel input;

b. a second output, capable of transmitting a signal from the second electromyogram channel input to the computer;

c. a second computer signal input, capable of receiving a data signal from the computer;

d. a second switch output; and

e. a second relay, activated by the second computer signal input, that electrically couples the power supply to the second switch output when a second signal is asserted at the second computer signal input, the second signal indicating that a bioelectrical impulse has been sensed by the second electromyogram channel input.

31. The device of claim 30, wherein the second output is compatible with a PCMCIA card.

32. The device of claim 30, further comprising

a. a third electromyogram channel input;

and

b. a third output, capable of transmitting a signal from the third electromyogram channel input to the computer.

33. The device of claim 32, wherein the second output is compatible with a PCMCIA card.

34. An electromyogram interface for sensing an input from a user, comprising:

a. a bioelectrical impulse sensor, capable of generating a first signal when a bioelectrical impulse is asserted;

b. a piezoelectric member, capable of generating a second signal when subjected to a mechanical force corresponding to a muscle movement; and

c. a detection system, responsive to the bioelectrical impulse sensor and the piezoelectric member, that determines if the input from the user has been asserted based on the first signal and the second signal, the circuit also capable of determining if either the bioelectrical impulse sensor or the piezoelectric member is malfunctioning and, thereby determining if the input from the user has been asserted even when one of the bioelectrical impulse sensor or the piezoelectric member is malfunctioning.

35. The electromyogram interface of claim 34, in which the detection system comprises a processor that compares a current state of the first signal and the second signal to a previous state of the first signal and the signal to determine if either of the bioelectrical impulse sensor or the piezoelectric member is malfunctioning.