27-09-2010, 05:30 PM
Cellphone_Land Rover.pdf (Size: 435.69 KB / Downloads: 567)
This article is presented by:
P. Raghavendra PRASAD and
K. Susram Rahul
ABSTRACT
Conventionally, wireless-controlledrobots use RF circuits,which have the drawbacks oflimited working range, limited frequencyrange and limited control. Useof a mobile phone for robotic controlcan overcome these limitations. Itprovides the advantages of robustcontrol, working range as large as thecoverage area of the service provider,no interference with other controllersand up to twelve controls.Although the appearance andcapabilities of robots vary vastly,all robots share the features of a mechanical,movable structure undersome form of control. The control ofrobot involves three distinct phases:preception, processing and action.Generally, the preceptors are sensorsmounted on the robot, processing isdone by the on-board microcontrolleror processor, and the task (action)is performed usingmotors or with someother actuators.
Overview
In this project, therobot is controlledby a mobile phonethat makes a call tothe mobile phone attachedto the robot. Inthe course of a call, ifany button is pressed,a tone corresponding to the buttonpressed is heard at the other end ofthe call. This tone is called ‘dual-tonemultiple-frequency’ (DTMF) tone.The robot perceives this DTMF tone. with the help of the phone stacked inthe robot.The received tone is processed bythe ATmega16 microcontroller with thehelp of DTMF decoder MT8870. Thedecoder decodes the DTMFtone into its equivalent binarydigit and this binarynumber is sent to the microcontroller.The microcontrolleris preprogrammed totake a decision for anygiven input and outputsits decision to motordrivers in order to drivethe motors for forwardor backward motion ora turn.The mobi le thatmakes a call to the mobilephone stacked in therobot acts as a remote. Sothis simple robotic projectdoes not require the constructionof receiver andtransmitter units.DTMF signaling isused for telephone signalingover the line in thevoice-frequency band tothe call switching centre.The version of DTMFused for telephone tonedialing is known as‘Touch-Tone.’DTMF assigns a specificfrequency (consistingof two separatetones) to each key sothat it can easily beidentified by the electroniccircuit. The signalgenerated by the DTMFencoder is a direct algebraicsummation, in real time, ofthe amplitudes of two sine (cosine)waves of different frequencies, i.e.,pressing ‘5’ will send a tone madeby adding 1336 Hz and 770 Hz to theother end of the line.
Overview
In this project, therobot is controlledby a mobile phonethat makes a call tothe mobile phone attachedto the robot. Inthe course of a call, ifany button is pressed,a tone corresponding to the buttonpressed is heard at the other end ofthe call. This tone is called ‘dual-tonemultiple-frequency’ (DTMF) tone.The robot perceives this DTMF tone. with the help of the phone stacked inthe robot.The received tone is processed bythe ATmega16 microcontroller with thehelp of DTMF decoder MT8870. Thedecoder decodes the DTMFtone into its equivalent binarydigit and this binarynumber is sent to the microcontroller.The microcontrolleris preprogrammed totake a decision for anygiven input and outputsits decision to motordrivers in order to drivethe motors for forwardor backward motion ora turn.The mobi le thatmakes a call to the mobilephone stacked in therobot acts as a remote. Sothis simple robotic projectdoes not require the constructionof receiver andtransmitter units.DTMF signaling isused for telephone signalingover the line in thevoice-frequency band tothe call switching centre.The version of DTMFused for telephone tonedialing is known as‘Touch-Tone.’DTMF assigns a specificfrequency (consistingof two separatetones) to each key sothat it can easily beidentified by the electroniccircuit. The signalgenerated by the DTMFencoder is a direct algebraicsummation, in real time, ofthe amplitudes of two sine (cosine)waves of different frequencies, i.e.,pressing ‘5’ will send a tone madeby adding 1336 Hz and 770 Hz to theother end of the line.