SAFETY AUTO BRAKE SYSTEM FOR HILL STATION

VEHICLE USING MEMS SENSOR

INTRODUCTION• The aim of the project is to design and construction of a module used

for vehicles in the hill stations. Auto breaking system is used when

vehicle is moving upward direction.

• The project was divided into two phases. The First phase is to

demonstrate the application of MEMS. The second phase of the

project attempts controlling motors.

• MEMS (micro-electro-mechanical-systems) sensor is interfaced to

micro controller using I2c protocol, microcontroller receives the data

from the MEMS sensor and process it according to the data from the

sensor appliances are operated.

ATMEGA 32

Power Supply

MEMS sensor

LCD Display

Driver Motor 1

Driver Motor 2

Block diagram

Atmega32 Micro Controller

•The Atmega8535 is a low-power CMOS 8-bit microcontroller

based on the AVR enhanced RISC architecture

•The Atmega8535 achieves throughputs approaching 1 MIPS per

MHz allowing the system designed to optimize power consumption

versus processing speed.

•The Atmel Atmega8535 is a powerful microcontroller that provides

a highly-flexible and cost-effective solution to many embedded

control applications.

Micro Electro Mechanical Systems (MEMS)

Micro electro mechanical systems (MEMS) (also written as micro-

electro-mechanical, Micro Electro Mechanical or microelectronic

and micro electro mechanical systems) is the technology of very

small mechanical devices driven by electricity; it merges at the nano-

scale into nano electro mechanical systems (NEMS) and

nanotechnology. MEMS are also referred to as micro machines (in

Japan), or micro systems technology – MST (in Europe).

MEMS are made up of components between 1 to 100 micrometers

in size (i.e. 0.001 to 0.1 mm) and MEMS devices generally range

in size from 20 micrometers (20 millionths of a meter) to a

millimeter. They usually consist of a central unit that processes

data, the microprocessor and several components that interact with

the outside such as micro sensors.

Working

The power supply to the circuit is given through a step down transformer

which reduces the 230 Volts AC supply to 12V AC, that is converted into pulsating

DC supply through the bridge rectifier used in the circuit. Now the pulsating DC is

passed through a filter this filtered output is pure DC, this filtered output is then

given to a voltage regulator and a 5 Volts DC supply is obtained and used to power

the various components used in the circuit. This 5 Volts DC supply is given to 40th

pin of the Microcontroller which is VCC, 9th pin of the Microcontroller for the

RESET button, LCD segment, driver IC (L293D).

The port C of the microcontroller is attached a pull-up resistor and interfaced

with LCD. Port A is given to the MEMS sensor and port D is connected to the

L293D driver IC. MEMS sensor is interfaced to micro controller using I2c

protocol, microcontroller receives the data from the mems sensor and process it

according to the data from the sensor appliances are operated.The output from

the MEMS sensor is given to the microcontroller, this chip converts it into

digital data. The output from the microcontroller is processed and the output is

shown in the LCD display and accordingly the motor is driven with the help of

the driver IC. The driver IC L293D is connected to the port D of the

microcontroller and it controls the dc motors. The direction of the motors and

the speed control of the motors are controlled by the driver circuit. The motors

are connected to the wheels of the vehicle and as the speed changes the

vehicles starts moving

The MEMS sensor senses the acceleration of the vehicle and

it is displayed in the LCD screen. As the vehicle moves the

MEMS sensor displays the difference in the acceleration. As the

vehicle climbs up the hill the speed of the motor speed changes

as there is a change in the acceleration of the values in the X and

Y plane. This speed is changed as it is already mentioned in the

source code and accordingly the braking system is applied by

decreasing the speed of the vehicle when the given acceleration

values are reached. Thus automatically braking system is applied

on the vehicle by using MEMS sensor.

Project kit

This is the module of the safety auto brake of hill station vehicle. In this module

all the components are kept on a single board. In the figure we can see the

transformer, power supply unit, L293D driver IC, ATMEGA 32 microcontroller,

MEMS sensor, LCD display and the motors are connected to the wheels of the

vehicle

The acceleration of the vehicle is sensed by the 3-axis accelerometer MEMS

sensor and the acceleration is displayed in the LCD display. The acceleration of

the vehicle in the X and Y axis is shown in the LCD display. The below figure

shows the values displayed in the LCD after the vehicle starts moving.

As the vehicle climbs up the hill the speed change. The MEMS sensor

senses the change in the difference in the X and Y axis and gradually the

acceleration of the vehicle decreases. As a result safety auto brake is applied

automatically.

This is the final output of the project. As the vehicle climbs up the hill the

speed of the vehicle decreases and brakes are applied using the L293 D driver IC

circuit. As a result, the vehicle moves up the hill safely without slipping back.

Future scope

Since the project made now is just a prototype, in future it can be used in any

vehicle in order to provide safety in order to avoid accidents and collisions of the

vehicles. Regenerative braking is used in the vehicles and the energy is saved and

it is stored in the battery for later use. This type of braking can be used in any

hybrid vehicles and we can reduce the use of fossil fuels in the vehicles.

Conclusions

The project SAFETY AUTO BRAKE SYSTEM FOR HILL STATION

VEHICLE USING MEMS SENSOR has been successfully designed and

tested. It has been developed by integrating features of all the hardware

components used. Presence of every component has been reasoned out and

placed carefully thus contributing to the best working of the unit. Secondly, using

highly advanced IC’s and with the help of growing technology the project has

been successfully implemented.

THANK YOU.