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!

New book

Python Programming and GUIs

This book is aimed at people who want to interface PCs with hardware projects using graphic user interfaces. The programming language used is Python, an object-oriented scripting language.