Robotic Floor Cleaner with Robotic Floor Cleaner with Obstacle Sensing Obstacle Sensing

TechniqueTechnique

By:By:Udit Chauhan (05-EL-Udit Chauhan (05-EL-

285)285)Sumit Kaul (05-EL-279)Sumit Kaul (05-EL-279)

Components Used:Components Used:

AT89S52 micro-controllerAT89S52 micro-controller IR Sensor for sensingIR Sensor for sensing LM567LM567 Crystal Oscillator 11.059 Crystal Oscillator 11.059

MHzMHz D.C. Motors ( D.C. 12 V )D.C. Motors ( D.C. 12 V ) LCD 16 x 2LCD 16 x 2 Battery 12VBattery 12V Voltage Regulator ( IC 7805)Voltage Regulator ( IC 7805) TransistorsTransistors CapacitorCapacitor DiodeDiode ResistancesResistances LEDsLEDs One Free Rotation WheelOne Free Rotation Wheel One Dusting PadOne Dusting Pad

CIRCUIT DIAGRAMCIRCUIT DIAGRAM

IR SensorsIR Sensors

The high-efficiency IRLED driven by pnp The high-efficiency IRLED driven by pnp transistor tbc369 with a modulating transistor tbc369 with a modulating frequency of about 20 khz (available from frequency of about 20 khz (available from IC LM567) emit infrared light.IC LM567) emit infrared light.

Whenever the IR beam is radiated by Whenever the IR beam is radiated by IRLED is reflected by a nearby object IRLED is reflected by a nearby object (obstacles), LM567 receives 20khz (obstacles), LM567 receives 20khz reflected signal at its pin 3 on detection by reflected signal at its pin 3 on detection by photo diode. As a result LM567 pulls its photo diode. As a result LM567 pulls its output pin low.output pin low.

LM567 – PLL tone decoderLM567 – PLL tone decoder

The LM567 and LM567C are general purpose tone The LM567 and LM567C are general purpose tone decoders designed to provide a saturated decoders designed to provide a saturated transistor switch to ground when an input signal transistor switch to ground when an input signal is present within the passband.is present within the passband.

The circuit consists of an I and Q detector driven The circuit consists of an I and Q detector driven by a voltage controlled oscillator which by a voltage controlled oscillator which determines the center frequency of the decoder.determines the center frequency of the decoder.

External components are used to independently External components are used to independently set center frequency, bandwidth and output set center frequency, bandwidth and output delay.delay.

LM 567 - PLL tone decoder IC LM 567 - PLL tone decoder IC

JHD162A -LCD UnitJHD162A -LCD Unit The 1, 3, 5, 16 pins of lcd The 1, 3, 5, 16 pins of lcd

controller is grounded.controller is grounded. Pin no 7 (DB0) to pin no 14 Pin no 7 (DB0) to pin no 14

are connected to P0 port of are connected to P0 port of controller for receiving controller for receiving data.data.

In lcd first the input is In lcd first the input is received at pin no 4 and received at pin no 4 and pin 6, after that the led is pin 6, after that the led is ready to read data and ready to read data and print it on the screen as print it on the screen as per the command given.per the command given.

AT89C51 - MicrocontrollerAT89C51 - Microcontroller

The AT89C51 is a low-power, high-performance The AT89C51 is a low-power, high-performance CMOS 8-bit microcomputer with 4K bytes of Flash CMOS 8-bit microcomputer with 4K bytes of Flash programmable and erasable read only memory programmable and erasable read only memory (PEROM).(PEROM).

Fully Static Operation: 0 Hz to 24 MHz.Fully Static Operation: 0 Hz to 24 MHz. 128 x 8-bit Internal RAM.128 x 8-bit Internal RAM. 32 Programmable I/O Lines.32 Programmable I/O Lines. Two 16-bit Timer/Counters.Two 16-bit Timer/Counters. Programmable Serial Channel.Programmable Serial Channel. Six Interrupt Sources.Six Interrupt Sources.

DC Gear MotorDC Gear Motor

VOLT: 12-18V. DC

R.P.M: 75-100

RelayRelay

A relay consists of a coil that may be A relay consists of a coil that may be energized by the low-voltage circuit and energized by the low-voltage circuit and one or more sets of switch contacts, which one or more sets of switch contacts, which may be connected to the high-voltage may be connected to the high-voltage circuit.circuit.

If a current is passed through the coil, the If a current is passed through the coil, the resulting magnetic field attracts the metal resulting magnetic field attracts the metal arm and acts as the Normally Open (N.O.) arm and acts as the Normally Open (N.O.) switch contact and the common switch switch contact and the common switch contact.contact.