7AIRBAGS IN TWO WHELERS
THE GOOGLE SCIENCE FAIR
Why airbags in two wheelers ?
Normally most deaths take place by accidents . About 70% of death is road accidents. In that 45% is two wheeler accidents. Few years back I saw an accident where the two wheeler hits with a car heavily . Car’s rider escaped because of air bag but the two wheeler’s rider had died .So I planned to take this project.
Road accidents Railways ac-cidents
Seaways ac-cidents
Airways ac-cidents
Natural disas-teres
Others
About me I am Master M.OHM ASHWIN studying Class VIII in The
Ashok Leyland School at Hosur, TamilNadu, INDIA. I always aspire for doing and achieving something
which bring credits to me. Last month I had participated in VIT-INNOVIT
competition in Vellore, TamilNadu and presented my project report on Hovercraft vehicle design and working concept which had won an award for me and which had encouraged me in doing a lot more similar excises or experiments of Innovative in nature and useful for the public.
In the same line now I have thought of a project “Airbags – Safety protection of two wheelers” which according to me is going to be a very interesting and futuristic project.
The question:The question comes to my mind is proving
totally successful considering rider and pillion rider convenience, economy, fail safe system etc.,
Hypothesis :An airbag is vehicle safety device which is occupant restraint consisting of a flexible envelope design to get inflated in no time (rapidly) during any automobile collision. This balloon like airbag is to prevent the driver and occupants already restrained with seatbelts from striking interior objects such as driving wheel, window, dash board etc.,
Suitable sensors are deployed in the car with one or two or more airbags locating in the Impact Zone with variable rate depending on the severity of impact. The existing designs seem to be inflated thro’ Pyrotechnic means and can be operated only once. Extending the concept of four wheeler to a two wheeler the basic idea has been formed by me.
Project Concept / Experiments / Research aspects :The automobile Industry started the airbag
research in the late 1950 and soon discovered that there were many difficulties in design, location, accommodation, actuation etc., etc., Crash tests conducted showed that1) an airbag will be useful as a PROTECTIVE
DEVICE, provided that the airbag must deploy and inflate within 40 milliseconds (really a fraction of a second)
2) The system considered must detect the difference between a severe crash or a minor fender-bender.
Hence the first component of airbag system is development of suitable SENSOR (with fast reaction time)that can detect “head-on Collision” and immediately trigger the airbags deployment.
Experiments:Concept development :
One of the simple design for the crash sensor could be a steel ball that slides inside a smooth bore or a fine finished plunger sliding effortlessly in a fine bore cylinder.
The ball or the plunger will be held in position by a stiff spring located at suitable place which inhibits the ball’s (plunger’s) motion when the vehicle rides over a bump or a pot hole.
However when there is a crash or head on collision involving the
vehicle front (say bumper , tyre/wheel etc) then there will be a
deceleration (sudden reduction in the velocity / speed of the vehicle ) but the impact makes the ball / plunger
moves forward and actuates an electric circuit or mechanical linkage with maximum advantage or release the valve port in the compressed pit air accumulator or a gas generator
which burns the liquid fuel or may be solid fuel to produce large volume of cooler gas (should not increase the
temperature more) to inflate the airbag immediately. In many cars,
gas generators use a small quantity of ‘PYROTECHNIC CHARGE’ will be used to open a valve which in turn begins the gas generation process. Some gas generators use hydrogen
peroxide for similar application.
Data:Similarity of Technique for two wheelers :
The prevailing motor bike design have very little scope to accommodate gas generator etc., but for a suitable simple mechanical linkage system tagged on to the existing elements of the bike which reads the pulse of the Impact. The general observation in Two wheeler head on collision :The pillion rider is thrown out if he or she is not holding the side mounted hand holders/brackets firmly.
Major issue :
Solution :
The Rider gets hurt by the impact on the handlebars or hitting against the dashed objects in the gap between the handle bar.
Provide an air bag to get inflated wherever there is a head on collision involving the front wheel dashing against the vehicle / object / tyre in the front. This bag will be placed over the fuel tank only where at present simple service bag or carry bag kind is placed on the petrol / fuel tank fully on the flat condition.
Operating mechanism : This concept to be adopted, engineered on any one of the bike, experimented with dummy rider / pillion to establish as road worthy safety device.
Concept :
The fork rods situated at both sides supporting the front wheel takes the impact of the load coming on the front tyre.
The shock absorber also placed at near-parallel to the fork to absorb the shock loads.The fork angle & the trail lead decide the movement of the shock absorber. We should make use of this up & down sliding motion for the basic sensor system.
Whenever this sliding motion reaches the maximum position (i.e. whenever the shock absorber is in the extreme compressed stage), the side mounted linkage on the shock absorber in the sliding arm should actuate the Accumulator or air reservoir having dry compressed air to release instantly to inflate the balloon like air bag fitted or placed on the petrol tank to protect the rider from the impact load.
Observation:What happens if the Driver / Rider looses the balance or whenever there is a side impact by another vehicle?For this, the first thought is to have
rigid side wheels (as used in the bike for handicapped) for stability. However these two side wheels will be held in a position 2”(50 to 60mm) above the ground level only.
How these side wheels help?
Whenever there is a head on collision where the front tyre hits, then these two side wheels are pushed down simultaneously along with the command signal from the accumulator for the lateral stability.
Whenever there is a impact load from the rear, if the road is free, then the vehicle (bike) will move forward or dash against the front vehicle. Whenever this happens, then the same action as explained earlier will happen & save.
Whenever a side load hit on either side, the opposite side
wheel which is only 2”inch above ground level will come to a help to some extent and both
of the riders are also having safety belts which should keep them safe against any impact. Actual safety system elements
like positioning with line diagram for actuations and also
possible/ probable fitment / functioning aspects of the
mechanism fitted on the two wheeler will be illustrated in
the following pages.
Impact Front Wheel
Linkage in Shock absorber
Air reservoir
Air bag inflate
sProtects the rider
Component Transfer
Force on shock absorber
Actuates the accumulator / gas generator
Air releaseIn-between handlebar
Linkage in the shock absorber
Pushes down the side-wheels to rest
on the ground
Lateral stability is maintained in the
vehicle
CONCLUSION:This technique of air bag in two wheelers saves from any major injury from the accidents and safer ride for both rider and pillion rider.Basically this idea works similar to the concept in car and the supporting wheels technique is an additional thought which will avoid the vehicle falling down even in light dashing as well as minor side hits. A simple and more economic idea save many human beings from accidents.Anyway we have to travel a long way to establish the credentials to have a full proof system in the long run.
THANK YOU