ABS (Antilock Braking System)

ANTILOCK BRAKING SYSTEM (ABS)

SYNOPSIS

The aim is to design and develop a control system based on the braking system of an electronically controlled safely automotive wheel braking system. Based on this model, control strategies such as an 'antilock braking system' (ABS) and improved maneuverability via individual wheel braking are to be developed and evaluated.

The anti-lock brake controller is also known as the CAB (controller anti-lock brake). An anti-lock braking system (commonly known as ABS, from the German name "Antiblockiersystem") is a system on motor vehicles which prevents the wheels from locking while braking. The purpose of this is twofold: to allow the driver to maintain steering control and to shorten braking distances.

The solenoid controlled braking system is used for this project. When the brake pedal or Bush Button is activated by the driver, the Solenoid Valve (Cut off Valve) activates/deactivate the pneumatic braking system simultaneously at a constant speed. The braking is applied gradually to the vehicle so that the vehicle stops smoothly with safe. 

INTRODUCTION

A recent typical ABS is composed of a central electronic unit, four-speed sensors (one for each wheel), and two or more hydraulic valves on the brake circuit. The electronic unit constantly monitors the rotation speed of each wheel. When it senses that one or more wheel is rotating slower than the others (a condition that will bring it to lock), moves the valves to decrease the pressure on the braking circuit, effectively reducing the braking force on that wheel.

On high-traction surfaces such as bitumen, whether wet or dry, most ABS-equipped cars are able to attain braking distances better (i.e. shorter) than those that would be possible without the benefit of ABS. A moderately-skilled driver without ABS might be able, through the use of cadence-braking, to match the performance of a novice driver with an ABS-equipped vehicle. However, for a significant number of drivers, ABS will improve their braking distances in a wide variety of conditions.

WORKING PRINCIPLE

The brake pedal or Bush Button was activated at the time of any braking time. The Electrical Signal is given to the solenoid valve when the pedal/Bush Button is activated. The compressed air is going to the solenoid valve.

            The solenoid valve is simultaneously activated at the time of pedal/Button pushed. The compressed air goes to the pneumatic cylinder. The compressed air pusses the pneumatic cylinder piston and move forward. The braking operation occurred at the of solenoid valve activated time. This activation of the solenoid valve is a continuous process and a constant and smooth so that the smooth braking operation is done.

            Another solenoid valve is deactivated at the time of pedal releasing time. The inside of the pneumatic cylinder air goes to the solenoid valve with the help of the exhaust port.

ADVANTAGES:

Ø  It requires simple maintenance cares

Ø  The safety system for the automobile.

Ø  Checking and cleaning are easy because the main parts are screwed.

Ø  Easy to Handle.

Ø  Manual power required is less

Ø  Repairing is easy.

Ø  Replacement of parts is easy.

Ø   No Oil wastage.

DISADVANTAGES

v Initial cost is high.

v High maintenance cost

           APPLICATIONS

Ø  It is very much useful for Car Owners & Auto-garages.  This Antilock braking system is used for smooth braking of the vehicles.

Ø  Thus it can be useful for the following types of vehicles;

1) MARUTI,  2) AMBASSADOR, 3) FIAT, 4) MAHINDRA,

 5) TATA