Society of Automobile Engineering,Southern section India. As a part of virtual baja 2017. Awarded as best. Detailed info regarding braking of a 4*4 offroad vehicle(ATV)

1. SAE INDIA

2. The Brake System
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3. Concept Of Braking
 A brake is a mechanical device that inhibits motion by absorbing energy from a
moving system.
 It is used for slowing or stopping a moving vehicle, wheel, axle, or to prevent its
motion, most often accomplished by means of friction.
 Uses friction between two surfaces pressed together to convert the kinetic
energy of the moving object into heat.
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4. Brake System Model4

5. Hydraulic System Configurations
 There are two layouts of hydraulic brake systems used in cars and light trucks.
 Front/Rear hydraulic split: Also called axle by axle, vertical, and some times
“black and white”.
 Diagonal Split: Also called criss-cross. The type of split is only significant in the
event of a hydraulic system failure.
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6. Diagonal Hydraulic Split System
 The diagonal split concept comes from the fact that the left rear and right front
brakes are on one hydraulic line while the right front and left rear brakes are on
another.
 The diagonal split system, because it maintains braking ability for both a front and
rear tire, is easier for the driver to control the vehicle in emergency brake failure.
 In a non-diagonal system, all the braking power would transfer to either just the
front or back tires, increasing the likelihood of skidding and possibly losing control.
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8. Brake Component Function8
4 Subsystems
Actuation
sub-systems ABS,EBD,ESP…
Parking brake
sub-system
Foundation
sub-systems

9. Actuation Sub-Systems
 Brake Pedal
 Master cylinder
 Proportionating valves
 Brake lines
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10. The Brake Pedal10
Pedal Ratio,
𝑋
𝑌
=6.2:1
620N

11. Master Cylinder
 A master cylinder is just a simple piston inside a cylinder.
 Master brake cylinders must be leak-proof – and stay that way.
 The outstanding features of Bosch master brake cylinders are their top quality and
long service life. They are made of cast iron or aluminum.
 The high quality standard is guaranteed by sophisticated production methods and
stringent checks, with tight tolerance specifications to ensure ideal functioning and
freedom from leaks.
 Optimized cylinder surfaces minimize cup abrasion and help to maintain the long-
term reliability of Bosch master brake cylinders.
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13. Basics of Master cylinder
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14. M/C Applied
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19. Foundation Brake System
 Linings
 Disc Brakes
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20. Brake Lines
 A reliable link: Brake hoses from Bosch form the flexible link between brake lines and
wheel brakes to ensure that the hydraulic pressure is ideally transmitted to the wheel
brake cylinders and brake calipers.
 Bosch brake hoses are made of multi-layered plastic/rubber material with fabric inlay.
 The diameter and connection method vary depending on the application.
 The outstanding quality of Bosch brake hoses pays dividends - not least in terms of
stable braking action.
 Steel tubing is used for rear wheels. Steel tubing helps to reduce degrees of freedom.
 3/16” o.d. is standard size.
 Very robust, can take a lot of abuse.
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21. Disc Brakes
 A disc brake is a type of brake that uses calipers to squeeze pairs of pads against
a rotor (or "disc") in order to create friction that retards the rotation of a shaft, such
as a vehicle axle, either to reduce its rotational speed or to hold it stationary.
 The energy of motion is converted into waste heat which must be dispersed.
 Hydraulic disc brakes are the most commonly used form of brake for motor
vehicles but the principles of a disc brake are applicable to almost any rotating
shaft.
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22. Exploded view of brake system
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29. Points to be Noted
 Keep it SIMPLE
 Keep it light; but not too light.
 If the rotor is too light it gets very hot
 Packaging and Integration drive 90% of design.
 Read the rules
 Allow enough time for details and testing
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QUERIES