By

ANIMESH SARKAR

NIE,mysore

Introduction

1. Safety in automobiles has always been a prime priority for both engineers and the customers.

2. Automobile safety is the study and practice of design, construction, equipment and regulation to minimize the occurrence and consequences of automobile accidents

3. The aim is to not only build effective cost efficient solutions but to also touch new heights in technology and development

Safety systems in automobiles can be classified into two

factors on the basis of their use before and after the accident

DONE TO AVOID AN

ACCIDENT Created to protect the

driver during the accident.

ACTIVE SAFETY IN DESIGN

SECTOR

• Automotive aerodynamics is the study of the

aerodynamics of road vehicles.

• It not only focuses on minimizing drag and noise

emission but also provides required stability to

the vehicle

• It reduces unwanted lift force caused by air

passing through gaps in fast moving vehicles.

1. Self-healing materials are a class of smart

materials that have the structurally

incorporated ability to repair damage caused

by mechanical usage over time.

2. Use of such materials in the manufacturing

of automobiles would reduce the risks of

internal damages due to stress and also cost

efficient maintenance.

WHY ?

When cars at high speeds suddenly apply brakes

the wheels tend to lock and are unable to be

steered . This leads to instability hence skidding.

How it works?

• Traction control system prevents

wheel spin in slippery condition when

the vehicle needs to be accelerated.

• TCS uses the same sensors like that

of ABS to detect whenever one of the

wheel goes faster than the others.

• The system can break a drive when

the wheel starts to spin and transfer

the torque to opposite drive wheel

that still has traction. In some cases

the TCS may reduce throttle opening,

shift the transmission to a higher

gear, and retard the ignition time in

order to reduce engine capacity.

• Interprets the speed and force by

which the driver executes brakes,

to determine whether it is an

emergency situation.

• The system then overrides and

fully applies the brakes until the

• ABS takes in control.

• In hilly regions vehicles with manual or semi-

automatic transmission face difficulty with

applying throttle In an incline.

• HILL ASSIST system activates automatically when

a gradient of 3% or more is detected. It then acts

to hold the car stationary for 2 sec after the

brake is released giving the driver time to apply

the throttle.

DIRECT TPMS:Here the sensors are used to monitor the tyres and has the advantage that It takes into account the factors such as tyre temperature when calculation of pressure

INDIRECT TPMS :. A decrease in tyre pressure will lead to decrease in the wheel radius.it means it will rotate faster compared to other tyres and the speed sensors will detect this change. The sensors in abs detect this and signal the driver

• A run flat tyre is a pneumatic

vehicle tyre that is designed to

resist the effect of deflation when

punctured and to enable the vehicle

to continue to be driven at reduced

speeds (up to 55mph), and for

limited distances up to 160 km .

ADAPTIVE CRUISE

CONTROL:• Adaptive cruise control (ACC) is an

intelligent form of cruise control

that slows down the speed up

automatically to keep in pace with

the car in front of you.

• The driver sets the speed –just as

wit cruise control –then the radar

sensor watches the traffic ahead,

locks on to the car ahead in a lane

ad instructs the car to stay 2,3 or 4

sec behind the car head. • Uses radar sensors, longitudinal

controller, digital sensor processor.

• Standard headlights shine straight

ahead, no matter what direction the car

is moving. When going around curves,

they illuminate the side of the road

more than the road itself.

• Adaptive headlights react to the

steering, speed and elevation of the car

and automatically adjust to illuminate

the road ahead. When the car turns

right, the headlights angle to the right.

Turn the car left, the headlights angle

to the left.

An automotive night vision system is a system using a

Thermo graphic camera to increase a vehicle driver's

perception and seeing distance in darkness or poor weather

beyond the reach of the vehicle's headlights

Passive infrared systems do not use an infrared light

source, instead they capture thermal radiation already

emitted by the objects, using a thermo graphic camera.

What is V2V?

• Vehicle-to-vehicle (V2V) communications

comprises a wireless network where

automobiles can communicate and alert

the drivers on the lane.

• It uses a wi-fi network of 5.9Ghz, which is

used by Wi-Fi. The range is up to 300

meters.

The technology is designed to alert the driver of cars and obstacles in his blind spot

while driving and parking, usually it will activate when the driver put on the

indicators , the system if detects any obstacle the light in you mirror starts flashing

and the steering starts to vibrate. This technology is limited to short ranges only.

• Active head restraint

• Air bags

• Seat belt pretensioners

ACTIVE HEAD RESTRAINT

An active head restraint moves forward and upward in

a rear-end collision to decrease the space between

the restraint and the occupant’s head, reducing the

degree to which the head accelerates before making

contact. The less acceleration, the lower the chance of

injury.

Using a lever-action mechanism built into a seat,

The beauty of this design is that it reacts

proportionately to the occupant’s motion

AIR BAGS

Air bags are air cushions that reduce the impact on

the body of the driver during a collision. The

sensors in the air bags sense the intensity of the

collision and inflate rapidly to protect the body of

the driver and the passengers.

SEAT BELT PRETENSIONERS

Seat belt pretensioners are typically pyrotechnic devices.

They are triggered along with the air bags; these are

slightly more sensitive as compared to the sensors for the

air bags and get activated in minor collisions. The

pyrotechnic device usually forms a part of the seat buckle.

A steel cable links the seat belts buckle to a piston that can

move along the steel tube. The steel tube attached to the

piston pulls down the seat belt and eliminates any kind of

slack in the belt.

Thus advance technology in automobile safety along with automation control systems has led

to drastic drop in fatality rate and further drop is projected by 2020 in European Union (ref

graph below).

Still in India the most advance system in safety is promoted to high end vehicles some times out

of reach for many. A change needs to be focused on Vehicle Law with mandatory safety system

in any vehicle which can save lives.

http://auto.howstuffworks.com/car-driving-safety/safety-regulatory-

devices/airbag.htm

http://www.extremetech.com/extreme/80512-volvo-targets-injuryproof-car-by-

2020

http://www.slideshare.net/geniusworks/futurecar-creating-the-future-of-

automotive?related=1

http://blogs.internetautoguide.com/6382672/auto-news/overview-of-the-bmw-7-

series-adaptive-headlight-technology/

http://www.futurevehicletechnologies.com/

http://www.nissan-global.com/EN/TECHNOLOGY/OVERVIEW/ldw.html\

http://en.wikipedia.org/wiki/Automotive_night_vision

http://auto.howstuffworks.com/adaptive-headlight.htm

http://auto.howstuffworks.com/car-driving-safety/safety-regulatory-

devices/airbag.htm