REMOTE CONTROLLING OF STEPPER MOTOR DIRECTION AND SPEED USING MOBILE.

By:E. Arun KumarN. ArchanaV. Swetha

Stepper Motor finds it applications in various areas.

• COMPUTER APPLICATIONS• INDUSTRIAL APPLICATIONS• WIND TURBINES

Block Diagram :

Mobile Phone

Micro Controller(AT89C52

)

L.C.D

D.T.M.F Decode

r

Motor Driver

Stepper Motor 1

Stepper Motor 2

Power Supply

Components :HARDWARE IC 7805 AT89C52 (UC)HT9170b (DTMF DECODER)ULN2803a (MOTOR DRIVER)Stepper MotorL.C.D ( HT44870)SOFTWARE Keil

Micro Controller :8K Bytes of In-System Reprogrammable

Flash MemoryEndurance: 1,000 Write/Erase Cycles Fully Static Operation: 0 Hz to 24 MHz Three-level Program Memory Lock 256 x 8-bit Internal RAM32 Programmable I/O Lines Three 16-bit Timer/CountersEight Interrupt SourcesProgrammable Serial ChannelLow-power Idle and Power-down Modes

Stepper Motor Types :• Unipolar Stepper Motor: Unipolar stepper motors

are characterised by their center-tapped windings.

Bipolar Stepper Motor: Bipolar stepper motors are designed with separate coils.

• Hybrid Stepper Motor : Variable reluctance stepper motor (also called hybrid motors) are characterised by one common lead.

Motor Driver :

• Output current up to 500mA• Output voltage up to 50V• Internal suppression diodes• Eight Darlington with eight emitters• Outputs can be parallelized

DTMF:Dual-tone multi-frequency signaling

(DTMF) is used for telecommunication signallingover analog telephone lines in the voice-frequency band between telephone handsets and other communications devices and the switching center.

A DTMF signal is the algebraic sum of two different audio frequencies, and can be expressed as follows:

f(t) = A0sin(2*П*fa*t) + B0sin(2*П*fb*t) + ………..   

• The frequencies associated with various keys on the keypad are shown in figure (A).

HT9170b :•Operating voltage: 2.5V~5.5V•Minimal external components•No external filter is required•Low standby current (on power down mode)•Excellent performance

L.C.D :Alpha Numeric L.C.D

with 16 pins.7-14 pins are data pins.L .C.D used is 2x16.

Flow Chart :start

Display Characters on L.C.D

If key presse

d

Stop

Display Corresponding Key on L.C.D rotate

motor depending on key pressed

Conclusion :It finds its application in X-Y Plotter used in industrial

applications.