ELECTRONICALLY ASSISTED SKID CONTROL SYSTEM FOR TWO-WHEELERWITH THE IMPLICATION OF GEAR REDUCTION FACILITATED ENGINE BRAKING

M.ASHWIN SRM EASWARI ENGINEERING COLLEGE

BHUVANESWARAN.P PANIMALAR INSTITUTE OF TECHNOLOGY

VARUN.C PANIMALAR ENGINEERING COLLEGE

ABSTRACT • In our country the number of lives that we lose due to two wheeler road accidents

is augmenting year by year. One of the major reasons for these accidents is found to be skidding of bikes due to unanticipated sudden braking. In this project we aim to reduce bike skidding by introducing immediate gear reduction at the time of unforeseen braking. Wheels generally lock up when brakes (Front & Rear) are applied excessively which eventually leads to skidding. So we are reducing wheel lock by minimising the usage of conventional friction brakes. With the help of a mechanical stopper we limit the usage of front brakes and immediate gear reduction limits the prolonged application of rear brakes. By increasing the engine braking force with automatic gear reduction the engine braking force is rapidly increased due to which vehicle speed is brought to control without wheel lock. This automatic braking is controlled by a pre-programmed micro controller which assists in reduction of gear. Thus we propose that this gear reduction assisted braking can prove to be a solution for bike skidding and has the potential to save humans’ life.

INTRODUCTION

Two wheeler accidents are increasing rapidly.

Most of the two wheelers used in India are budget bikes and are below 150cc.

It is not feasible to bring ABS and other safety

braking systems to these bikes.

STATISTICS

According to 2013 road accident data, 26.3% of all road crashes involved two-wheelers and the number of people killed in such accidents was 39,353.

Two wheelers account for 25% of total road crash deaths.

1214 road crashes occur every day in India.

CONCEPTDuring unanticipated braking wheels lockup when

brakes are applied excessively which leads to skidding.

So we limit the usage of brakes and we reduce the speed of vehicle through automatic gear reduction. (controlled engine braking)

Through gear reduction large amount of engine braking force is produced which reduces the vehicle speed during sudden braking on unfavourable conditions(sand, wet conditions etc)

WORKING

• When Speed of the vehicle exceeds 35kmph the front brake limiter comes into action.

• At unforeseen conditions and harsh road conditions wheels lock up due to sudden severe braking.

• When brakes are applied severely it is sensed by a sensor and gear is reduced instantaneously.

• To release the hand from holding the clutch high intensity dual shock vibrator is placed near the clutch lever.

FLOWCHART

SUDDEN BRAKING

HARSH ROAD CONDITIONS

(WET&SAND)

UNFORESEEN CONDITIONS

VEHICLE SPEED ABOVE 35KMPH

VEHICLE SPEED SENSOR

MICROCONTROLLER

FRONT BRAKE LIMITER

BRAKE SPEED

SENSORS

GEAR REDUCTION MOTOR

CLUTCH LEVER VIBRATOR

GEAR REDUCED AND CLUTCH

ENGAGED

VEHICLE STOPS.

ELECTROMAGNETIC CLUTCH

DESIGN OF FRONT BRAKE LIMITER IN HANDLEBAR

FRONT BRAKE LIMITER

MODIFIED GEAR PEDAL WITH REDUCTION MECHANISM

ANALYSIS OF GEAR PEDAL

ANALYSIS OF GEAR PEDAL

CALCULATIONS (REAR BRAKE) Force applied on the pedal, Fpedal = 10N Advantage offered by the pedal, Advpedal = (a/b) = 2.625~2.5 Advantage offered by the drum lever, Advlever = (d1/c1) =

5.278~5 Force applied at the cam, Fcam = Fpedal × Advpedal ×

Advlever =125 kgf Coefficient of friction between brake shoe and brake drum, µ

= 0.4 Maximum force applied by the brake shoes, Fmax = 2 × Fcam

× µ =100 kgf Maximum brake torque, Tmax = Drum Diameter × Fmax =0.15

×100 =15 kgf-m

CALCULATIONS(FRONT BRAKE) Force applied on the lever, Flever = 35N=3.5 kgf Advantage offered by the hand lever, Advlever1 = (l2/l1) = 4 Advantage offered by the drum lever, Advlever2 = (l3/l4) = 5.278 Cable efficiency, η = 0.8 Force applied at the cam, Fcam = Flever × Advlever1 ×

Advlever2 = 72.8 kgf Coefficient of friction between shoe and drum, µ = 0.4 Maximum force achieved by the brake, Fmax = 2 × Fcam × µ =

58.24 kgf Maximum brake torque, Tmax = Drum Diameter × Fmax = 0.15 ×

58.24=8.74

CALCULATIONS WITH LIMITERIf front brake is limited with the help of a stopper,Force applied on lever is approximately 60% of full force. Force applied on the lever, Flever = 0.6 ×35=21N=2.1kgf Advantage offered by the hand lever, Advlever1 = (l2/l1) = 4 Advantage offered by the drum lever, Advlever2 = (l3/l4) = 5.278 Cable efficiency, η = 0.8 Force applied at the cam, Fcam = Flever × Advlever1 × Advlever2 =

43.68 kgf. Coefficient of friction between shoe and drum, µ = 0.4 Maximum force achieved by the brake, Fmax = 2 × Fcam × µ = 34.9kgf Maximum brake torque, Tmax = Drum Diameter × Fmax = 0.15 ×

34.9=5.2 kgf.

ADVANTAGES

Stopping distance is reduced drastically when compared to other braking systems

Possibility of failure is very less as most of the braking is depended on controlled engine braking force.

It is very cheap when compared to other safety braking systems like ABS.

Human intervention is very less because entire system is completely automatic.

Cost of the entire system is less than three thousand rupees so it is very much possible in budget bikes

Can be implemented in bikes having both disk and drum brakes.

CONCLUSIONSafety braking system has been designed by us

which is very effective in any conditions.It has the potential to control skidding and

prevent accidents.This system is designed in such a way that it can

installed in budget bikes which are more vulnerable to accidents.

So we hope it has the potential to save human lives.