Aerial Armour for Vehicles
PROJECT BY: KUMAR RISHABH and ANAGH PRASAD, IIT Delhi

INTRODUCTION
Every year more than 1.3 million people die worldwide due to car accidents. As engineering students, it’s our passion to try to find solutions to such problems. For this purpose we wish to develop a system which can help in protecting lives of many people. The basic idea of this system is use of air bags outside the car which reduces the impact of collisions and most importantly these air bags will inflate before the collision. For this we will use the concept of fusion of sensors. We will use Lidar & hall effect sensors in our cars.

MOTIVATION: We were highly fantasised by the use of air bags for safe landing of vehicle in the NASA Pathfinder project. It motivated us to use similar technology for cars.

AIR BAGS (SAVE MILLION LIVES)
The concept of using air bags in cars is not new but they are used only inside the car at present. In air bags sodium azide(NaN3) is used. It is a stable compound but when heated it decomposes to Na and N2. This N2 is used in air bags. Most important fact is that inflation time of air bags is only 0.03 sec. Also air bags are made up of nylon polymer which can sustain a lot of pressure without bursting.

DESIGN BACKGROUD

To make our system affective we should consider different road accident scenarios.

Type 1-when the car fell off from a cliff or the car starts toppling.
In this situation Lidar sensors will be installed at the bottom of the car. The sensor measures the distance between the car and the road but when it topples or falls from an elevation then this value will change and sensors are activated.

Type 2-when the car skids on a wet road.
When a car skids then its wheel translates without rotating. So hall effect sensor is installed in the car which will measure its rpm. If the rpm value reduces drastically to zero then our hall effect sensor activates. After the activation of sensor microcontroller will take input from sensor and then air bags are inflated.

COST
The cost of an air bag is 500 US $. For this system we will need 5 air bags. So the cost of production is (500*5 + cost of sensors & microcontroller) = 3000$. So this amount is really less as compared to the money which we lose in an accident.

CONCLUSION
If we use this system in our cars then we can save lives of many people who die in road accidents; moreover air bags also protect the car from heavy damage, by absorbing most of the resulting stress and prevent injury which happens due to broken car parts. Although this design doesn’t consider all the scenarios of road accidents it will surely minimize the number of deaths due to road accident.