Touch screen controlled automatic wheel chair and home
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Transcript of Touch screen controlled automatic wheel chair and home
TOUCH SCREEN CONTROLLED AUTOMATIC WHEEL CHAIR AND HOME APPLIANCES.
Presented by Under the guidance of P.V.BHAVANA Mr. M.SUNDARARAO sir12C51A0458 Asst.prof
CONTENTS
Abstract Motivation Challenges Methodology Application Pros and Cons Future scope Conclusion
ABSTRACT
It is very difficult for the physically challenged people, to move and operate house hold appliances by their own.
The proposed seminar based on touch screen technology enables them to move independently without any external aid and at the same time it also helps them to operate home appliances using wireless communication.
MOTIVATION
A physically disabled person come across many problems while locomotion and it becomes more difficult for such a person to go near and operate the conventional switches .
To solve this problem a wheel chair is designed which can be controlled by the user and at the same time conventional switches are replaced with centralized control system to operate the house hold appliances located at remote places.
CHALLENGES Large touch screen leads to decrease in battery life. Stress on human fingers for large use. Automatic braking system is not in use.
METHODOLOGY
Touch screen technology is the direct manipulation type, gesture based technology.
A switch is placed on the wheel chair to perform two different types of operations i.e. either the movement of wheel chair or the house hold appliances control
Transmitter block diagram
LPC2148Micro controller
Power supply 16x2 LCD
Zigbeetransmitter
Drivercircuit for DC motor
Dcmotor
Dc moto
r
wheel
wheel
ResistiveTouch screen
switch
POWER SUPPLY
A power supply circuit is used to feed the microcontroller with 3.3v
SWITCH A switch is used to perform two different operations For one state of switch the signal from the touch screen is given
to the wheelchair to move in required direction. For second state ,the input signal is used to control house hold
appliances using zigbee technology
Touch screen A touch screen is capable of detecting and effectively
locating a touch over its display area. It is a 4-wire analog resistive touch screen, that is by
touching the screen at one point, resistance will vary for both X and Y axis.
By applying voltage across each axis, a change in resistance results in a change in voltage which is analog.
Lpc2148 microcontroller The analog output produced by the touch screen is given to
the ADC pins of micro controller. LPC2148 process and compares the obtained digital values
with the predefined range values. Accordingly it send instructions to direct the movement of
the chair and when switch is in state two, the same input is considered to control home appliances
Dc motors and its drivers Two 100rpm DC motors are used to control the movement of
wheel chair. To drive the motors having high torque, a driver circuit is
designed using mosfets and L293D An L293D circuit can control two motors simultaneously which in turn controls four wheels.
Zigbee transmitter and receiver
ZigBee is an IEEE 802.15.4-based specification for a suite of high-level communication protocols used to create personal area networks with small, low-power digital radios.
When switch state is zero, the input from the touch screen is given to ARM7 microcontroller, which transmits the input data serially to zigbee transmitter.
The data transmitted by zigbee transmitter is received by zigbee receiver in the receiving circuit.
The zigbee receiver sends the information to the microcontrollerAT89S52 ,that controls the home appliances.
Receiver block diagram
AT89S52 MICRO
CONTROLLER
Power supply
Zigbee reciever
16x2 LCD
Darlington pair for two relays
relay1
relay2
bulb
At89s52 microcontroller.
The AT89S52 is a low-power, high-performance 8-bit microcontroller with 8K bytes of in-system programmable Flash memory
It receives the digital signal from zigbee receiver It processes the received information to Darlington pair of relays.
Darlington pair
Two transistors with a common collector configuration and connected in a cascaded form constitute a Darlington Pair.
A Darlington pair circuit is designed to get current gain to operate the relay.
Relay A relay is an electromagnetic switch operated by a relatively
small electric current that can turn on or off a much larger electric current.
Hence in the receiver section relays act as switches that are connected with different home appliances.
16X2 LCD The LCD acts as an output device to display the function which is being performed by the microcontroller
APPLICATIONS
For paralyzed people
In hospitals
For para athletics
PROS AND CONS
PROS Highly user friendly. Easy to design and manufacture. Highly portable Less wired complexion.
CONS Collision avoidance mechanism
is absent. Absence of auto braking
mechanism.
FUTURE SCOPE
We can use voice command IC to interface our voice signal with micro controller.
This project can be extended by including GSM that sends an SMS during emergency.
Research is going on development of handicap wheelchair using nervous system of human.
CONCLUSION
Touch screen based control system is implemented for moving the wheel chair in all directions and the same control system is used to switch on and off the home appliances located in remote places using Zigbee technology.
This system will be very helpful for the people who cannot move without any external aid.