Home › Magazines › 2007 › July/August › Stereo Robot Ears

Stereo Robot Ears

Published in issue 367, July/August 2007

Stereo Robot Ears

Service robots of the future will most likely need to act on spoken commands and be able to recognise voices. This article takes a look at one aspect of this behaviour namely locating the position of a sound source using the cross-correlation function. A technique is developed which drastically cuts down on the number crunching so that even a basic microcontroller fitted with binaural sensors can pinpoint a continuous audio signal with an accuracy of just 10 degrees.

Resistors

R1,R5,R12 = 47kΩ

R2 = 33kΩ

R3,R10 = 22kΩ

R4,R11 = 1kΩ

R6,R9,R13,R16,R18,R19,R20 = 10kΩ

R7, R14 = 2kΩ2

R8, R15 = 100kΩ

R17 = 100kΩ preset

Rx = 100kΩ

 

Capacitors

C1,C2,C3,C4 = 1µF 16 V

C5 = 22µF 16 V

C6 = 100µF 16 V

C7,C8 = 100nF

C9,C10 = 22pF

 

Semiconductors

IC1 = LM324

IC2 = PIC16F88, programmed, order code 060040-41 from Elektor SHOP

Miscellaneous

Q1 = 20MHz quartz crystal

DIL14 socket

DIL18 socket

SL1,SL2,(SL4),SL5,SL6,SL7 = 2-way SIL pinheader (SL4 bridged with a 100k resistor, see text)

SL3 = 6-way SIL pinheader

JP1,JP2 = jumper

MicR, MicL = CZ034 electret microphone insert

PCB, ref. 060040-1, free artwork download

Click below to download a PDF copy of this article from Elektor magazine.

 

Downloads 

PDF article
10 Elektor Credits
PCB layout
Free download
 

Order this magazine 

Magazine July/August 2007
UK-367 (US $ 9.20)
 

Order from Elektor 

Programmed controller PIC16F88
060040-41 (US $ 16.20)
 

Order from ThePCBShop 

PCB, bare

 

Free downloads 

Binaural_v132.hex

Free download

Please note. In view of the complexity of international markets, Elektor cannot guarantee the availability of components for this project.

Subscribe now

Subscribe to our free
E-weekly Newsletter!

Enter your Email address:

Sponsored


Design your unique front panel with our free CAD software - it is quick and easy! Front Panel Express will machine your design with modern CNC technology. You will receive the panel exactly as you need it in a couple of days.

FAQ

Before submitting questions, review our FAQ section!

Benefit now

Audio Collection Bundle

19% Discount !

This complete range of The Audio Collection offers you access to more than 225 different audio circuits originally published in Elektor Electronics magazine between 1996 and 2008.