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

1. ELECTRONICALLY ASSISTED SKID CONTROL SYSTEM FOR TWO-WHEELER
WITH 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

2. 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.

3. 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.

4. 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.

5. CONCEPT
During 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)

6. 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.

7. 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

8. DESIGN OF FRONT BRAKE LIMITER IN
HANDLEBAR

9. FRONT BRAKE LIMITER

10. MODIFIED GEAR PEDAL WITH
REDUCTION MECHANISM

11. ANALYSIS OF GEAR PEDAL

12. ANALYSIS OF GEAR PEDAL

13. 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

14. 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

15. CALCULATIONS WITH LIMITER
If 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.

16. 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.

17. CONCLUSION
Safety 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.