University of Southern MindanaoKabacan, CotabatoDepartment of Electronics and Computer EngineeringCollege of Engineering and Computing

Mobot

Rizza A. Unabia5BSECE-A

Engr. Jeannalen P. LunodInstructor

October 2012IntroductionMobotis anautomatic machinethat is capable of movement in a given environment. It has the capability to move around in their environment and are not fixed to one physical location. Radio-controlled(orR/C)carswhich is a self-powered model car trucks that can be controlled from a distance using a specialized transmitter, is used to form this mobot together with its sensor. Sensors are essential parts of mobots, without such devices it could not gather information about the environment in which it activates and navigation would not be possible. Light dependent resistor (LDR)is used for its sensor. It is aresistorwhoseresistancedecreases with increasing incident light intensity; in other words, it exhibitsphotoconductivity. This sensor will able the mobot to sense and follow black line or curve. Together with the sensor circuit, PIC microcontroller is used. A program that is coded to move forward, left and right is loaded in it.

Block Diagram

SENSOR-This mobot uses Light dependent resistors (LDR) in its sensors. The LDRs sense the brightness of the area being sensed and directing the mobot to the right path.

Switch

PIC-16F84AThis microcontroller receives input from the sensor and controls the driver to move in line with the pathleft, right, forward. It this then outputted to the driver.

DRIVER

List of Materials

(1) PIC 16F84A(1) 18-PIN DIP IC Socket(1) RC Car w/ motor drivers (2) 470/6V(2) 220/6V(7) 10k, W(3)330 , W(1) 22pF, ceramic capacitor (1) LM324 Op Amp Transistor(1) 14 PIN DIP IC socket(4) 1K, W(4) LED-white(4) LDR (Light dependent resistors)(4) LED (as indicators)(4) Trimmers 10k, 1/4W(4) 100, WJumpersConnecting wiresPCBSoldering leadFerric Chloride(2) 1.5V rechargeable batteries(1) 9V battery

Schematic Diagram

SensorSource Code

porta equ 0x05portb equ 0x06 org 0x00

startmovlw 0xff trisporta movlw 0x00 tris portbclrfportb

test1btfscporta,1gototest2btfscporta,2gototestaagotoforwardtest2btfscporta,2gototestbbbtfscporta,3gotorightgotorighttest3btfscporta,3gotoforwardgoto right

testaabtfscporta,0gotoleftgotolefttestbbbtfscporta,0gototest3gotoleft

forwardmovlw 0x01movwf portbgoto test1rightmovlw 0x03movwf portb goto test1leftmovlw 0x05movwf portbgoto test1 end