Methods and apparatus for hands-free operation of a voice recognition system

• US 6,594,632 B1
• Filed: 11/02/1998
• Issued: 07/15/2003
• Est. Priority Date: 11/02/1998
• Status: Expired due to Term

• Current Assignee: NCR Voyix Corporation
• Original Assignee: NCR Corporation
• Inventors: White, Daniel F.
• Primary Examiner(s): ABEBE, DANIEL DEMELASH
• Application Number:
  US09/184,801
• Time in Patent Office: 1,716 Days
• Field of Search: 704/246, 704/251, 704/275, 704/270
• US Class Current: 704/270
• CPC Class Codes: G10L 15/22 Procedures used during a speech recognition process, e.g. man-machine dialogue

Abstract

Techniques for activating a voice recognition system are described. The system disclosed can be non verbally started and stopped without the need for the system user to use his or her hands facilitating hands-free operation in an environment with a relatively high degree of ambient background verbal noise. For example, a user may start the voice recognition system by blowing once on a microphone and stop the system by blowing twice on a microphone. The user may alternately start and stop the system by using other nonverbal inputs such as facial expressions, clearing the throat or moving one'"'"'s head. Such other nonverbal inputs may be detected by pressure sensors or motion sensors. The operational state of the system may alternately be toggled from off to on, or from on to off, with each subsequent nonverbal input.

Claims

1. A hands-free method for starting and stopping a voice recognition system, the method comprising the steps of:

storing in a computer memory a set of reference nonverbal voice signals, said nonverbal voice signals representing commands to start and stop a voice recognition system;

reading into a computer memory a signal from a microphone;

comparing said signal from said microphone to said set of reference nonverbal voice signals;

sending start or stop commands to a voice recognition system if said signal from said microphone matches one of the set of said reference nonverbal voice signals; and

starting and stopping the voice recognition system based upon the start and stop commands.

2. The method of claim 1 wherein said set of reference voice signals is comprised of:

a nonverbal voice signal representing the sound of blowing once into the microphone; and

a nonverbal voice signal representing the sound of blowing twice into the microphone.

3. The method of claim 2 wherein said voice signal representing the sound of blowing once into the microphone generates a command to start the voice recognition system and the voice signal representing the sound of blowing twice into the microphone generates a command to stop a voice recognition system.

4. The method of claim 1 wherein said set of reference voice signals is comprised of a nonverbal voice signal representing the sound of clearing the throat once or twice.

5. The method of claim 4 wherein said voice signal representing the instance of once clearing the throat generates a command to start the voice recognition system and the instance of twice clearing the throat generates a command to stop the voice recognition system.

6. The method of claim 1 wherein said set of reference voice signals is comprised of voice signals representing the sound of clucking the tongue.

7. The method of claim 6 wherein said voice signal representing once clucking the tongue generates a command to start the voice recognition system and twice clucking the tongue generates a command to stop the voice recognition system.

8. A hands-free method for starting and stopping a voice recognition system, the method comprising the steps of:

storing in a computer memory a reference nonverbal voice signal, said reference nonverbal voice signal representing a command to toggle the operational state of a voice recognition system;

reading into a computer memory a voice signal from a microphone;

comparing said voice signal from said microphone to said reference nonverbal voice signal; and

sending a toggle command to a voice recognition system if said voice signal from said microphone matches said reference nonverbal voice signal, said toggle command switching the voice recognition system to an active operational state if the voice recognition system is in an inactive operational state or to an inactive operational state if the voice recognition system is in an active operational state.

9. The method of claim 8 wherein said reference voice signal is comprised of a nonverbal voice signal representing the sound of blowing into the microphone.

10. The method of claim 8 wherein said reference voice signal is comprised of a nonverbal voice signal representing the sound of clearing the throat.

11. The method of claim 8 wherein said reference voice signal is comprised of a nonverbal voice signal representing the sound of clucking the tongue.

12. An apparatus for non verbally starting and stopping the operation of a voice recognition system, said apparatus comprising:

a microphone;

a filter for passing frequencies that represent nonverbal voice signals; and

a logic circuit for controlling the operation of a voice recognition system, said logic circuit being operable to monitor the output of said filter and being further operable to determine when to issue start and stop commands to said voice recognition system based upon the output of the filter exceeding a predetermined threshold level and further based upon the output of the filter comprising nonverbal voice signals.

13. The apparatus of claim 12, further comprising an annunciator, said annunciator indicating the operational status of the voice recognition system.

14. The apparatus of claim 12, further comprising a headset, said headset comprised of said microphone and one or more speakers.

15. The apparatus of claim 12 wherein said filter and said logic circuit are contained on an adapter card for use with a POS terminal.

16. The apparatus of claim 15 wherein said filter is an analog-to-digital converter.

17. A method for calibrating an apparatus for controlling the operation of a voice recognition system, the method comprising the steps of:

measuring the volume and frequency content of the ambient background noise from a microphone to generate a first calibration signal;

measuring the volume and frequency of nonverbal voice signals from a microphone to generate second and third calibration signals, said nonverbal voice signals representing start and stop commands for use with the voice recognition system; and

modifying the volume and frequency response of a filter to correspond to the first, second and third calibration signals.

18. The method of claim 17 further comprising the steps of:

determining minimum and maximum threshold volume levels by voicing nonverbal test signals into said microphone.

19. A method for calibrating an apparatus for controlling the operation of a voice recognition system, the method comprising the steps of:

measuring the volume and frequency content of the ambient background noise from a microphone to generate a first calibration signal;

measuring the volume and frequency of a nonverbal voice signal from a microphone to generate a second calibration signal, said nonverbal voice signal representing a toggle command for use with the voice recognition system; and

modifying the volume and frequency response of a filter to correspond to the first and second calibration signals.