Presented By :-Presented By :-

SEMINAR REPORT ONSEMINAR REPORT ON VECHILE SKID CONTROL VECHILE SKID CONTROL

SANGRAM KISHORE MOHARANAREGD NO:-0701206093

INTRODUCTIONINTRODUCTION Vehicle skid can be defined as the loss of traction Vehicle skid can be defined as the loss of traction

between a vehicle’s tyres and the road surface due to between a vehicle’s tyres and the road surface due to the forces acting on the vehicle. the forces acting on the vehicle.

To counter these skids and to prevent accidents To counter these skids and to prevent accidents Vehicle Skid Control (VSC) is incorporated in the Vehicle Skid Control (VSC) is incorporated in the vehicle which takes the safety aspects of the driver vehicle which takes the safety aspects of the driver and the vehicle to the next level . The VSC system and the vehicle to the next level . The VSC system electronically monitors speed and direction , and electronically monitors speed and direction , and compares the vehicle's direction of travel with the compares the vehicle's direction of travel with the driver's steering, acceleration and braking input. driver's steering, acceleration and braking input. VSC can help the driver compensate for loss of VSC can help the driver compensate for loss of lateral traction , which can cause skids and loss of lateral traction , which can cause skids and loss of vehicle control.vehicle control.

CAUSESCAUSESThe main causes of skidding are as follows :The main causes of skidding are as follows :

HARSH OR SUDDEN ACCELERATION. HARSH OR SUDDEN ACCELERATION.

EXCESSIVE OR SUDDEN BRAKING.EXCESSIVE OR SUDDEN BRAKING.

COARSE OR JERKY STEERING COARSE OR JERKY STEERING MOVEMENTS .MOVEMENTS .

OVERSTEER AND UNDERSTEEROVERSTEER AND UNDERSTEER . .

TYPES OF SKIDTYPES OF SKID

The main types of skid are :The main types of skid are :

THE FRONT WHEEL SKID.THE FRONT WHEEL SKID.

THE REAR WHEEL SKID.THE REAR WHEEL SKID.

THE FOUR WHEEL SKID.THE FOUR WHEEL SKID.

THE FRONT WHEEL SKIDTHE FRONT WHEEL SKID CHARACTERISTICSCHARACTERISTICS The car tends to take a course outside of The car tends to take a course outside of the expected course. The car is said to understeer. the expected course. The car is said to understeer. UNDERSTEERUNDERSTEER Understeer occurs when the front slip angle is Understeer occurs when the front slip angle is

greater than the rear and the car goes straighter greater than the rear and the car goes straighter rather than following the intended turn .rather than following the intended turn .

CAUSECAUSE Excess speed on entry to a hazard .e. a corner or Excess speed on entry to a hazard .e. a corner or

bend,bend, of destabilizing the vehicle making it more of destabilizing the vehicle making it more vulnerable to a loss of control.vulnerable to a loss of control.

THE REAR WHEEL SKIDTHE REAR WHEEL SKID CHARACTERISTICSCHARACTERISTICS The rear of vehicle swings out of line and gives the The rear of vehicle swings out of line and gives the

impression of trying to overtake the front the car is said to impression of trying to overtake the front the car is said to oversteer.oversteer.

OVERSTEEROVERSTEER Oversteer occurs when the rear tyres have a greater slip angle Oversteer occurs when the rear tyres have a greater slip angle

than the front tyres and the back threatens to overtake the than the front tyres and the back threatens to overtake the front, causing the vehicle to spin. front, causing the vehicle to spin.

CAUSECAUSE As with the front wheel skid, excessive speed into the hazard As with the front wheel skid, excessive speed into the hazard

and sudden braking , destabilising the vehicle, are the main and sudden braking , destabilising the vehicle, are the main causes of this skid.causes of this skid.

FOUR WHEEL SKIDFOUR WHEEL SKID

CHARACTERISTICS :-CHARACTERISTICS :- All four wheels have locked up and the vehicle is All four wheels have locked up and the vehicle is

sliding in the direction that the forward momentum is sliding in the direction that the forward momentum is carrying it, with no directional control carrying it, with no directional control

CAUSECAUSE :-:- Harsh or sudden braking has caused the wheels to Harsh or sudden braking has caused the wheels to

lock. A sensation of increase in the vehicle’s speed lock. A sensation of increase in the vehicle’s speed often occurs.often occurs.

SKID CONTROLSKID CONTROL

Stability control systems or skid control systems Stability control systems or skid control systems with names like StabiliTrak, Dynamic Stability with names like StabiliTrak, Dynamic Stability Control, Stability Management, and Vehicle Skid Control, Stability Management, and Vehicle Skid Control are the latest advancement in vehicle Control are the latest advancement in vehicle safety . A vehicle skid control system actually safety . A vehicle skid control system actually detects when a driver has lost some degree of detects when a driver has lost some degree of control. Luxury cars, such as the Mercedes control. Luxury cars, such as the Mercedes Benzes, BMW, Lexus, etc. now sold in India, Benzes, BMW, Lexus, etc. now sold in India, have stability systems installed that are have stability systems installed that are designed to remove oversteer or understeer.designed to remove oversteer or understeer.

COMPONENTSCOMPONENTSThe Vehicle Skid Control is made by the combination of The Vehicle Skid Control is made by the combination of different electronic and mechanical components. Some different electronic and mechanical components. Some of the components are those used in Anti-lock Braking of the components are those used in Anti-lock Braking System (ABS), and an electronically controlled engine System (ABS), and an electronically controlled engine throttle, as well as a dedicated computer and sensors, throttle, as well as a dedicated computer and sensors, providing information to the VSC system. These include:providing information to the VSC system. These include:

Yaw rate sensor. Yaw rate sensor.

G-sensor.G-sensor.

Steering angle sensor. Steering angle sensor.

Electronic throttle control. Electronic throttle control.

Slip indicator.Slip indicator.

Computer.Computer.

WORKINGWORKING

The heart of all these systems is a The heart of all these systems is a central processor that takes central processor that takes information from a number of information from a number of sensors, and then determines sensors, and then determines whether the car is in a stable or whether the car is in a stable or unstable state unstable state

REMEDIAL MEASURESREMEDIAL MEASURES In each case, the cause can be removed by taking In each case, the cause can be removed by taking

the foot off the accelerator or brake and depressing the foot off the accelerator or brake and depressing the clutch. The reasons are as follows:-the clutch. The reasons are as follows:-By decelerating, the vehicle’s speed is lowered, By decelerating, the vehicle’s speed is lowered, which in turn will start to reduce the magnitude which in turn will start to reduce the magnitude of the skid.of the skid.Relaxation of the pressure on the brake pedal Relaxation of the pressure on the brake pedal will unlock the wheels and allow the tyres to will unlock the wheels and allow the tyres to regain traction, enabling the vehicle to be regain traction, enabling the vehicle to be steered.steered.By depressing the clutch pedal .By depressing the clutch pedal .

ADVANTAGESADVANTAGES

Monitors each wheel independently Monitors each wheel independently maximizing the performance of the car.maximizing the performance of the car.Increases comfort, both physical and Increases comfort, both physical and psychological. psychological. Improves safety aspects of the car and the Improves safety aspects of the car and the driver.driver.Helps save money long term.Helps save money long term.Enhances the ability to dodge a renegade Enhances the ability to dodge a renegade object in its pathways.object in its pathways.

DISADVANTAGESDISADVANTAGES

High initial costs.High initial costs.

Overdependence.Overdependence.

Not perfect.Not perfect.

Repairing cost may be highRepairing cost may be high

CONCLUSIONCONCLUSION

Driving has become more and more Driving has become more and more dangerous with the ever increasing dangerous with the ever increasing population of man and vehicles. It is population of man and vehicles. It is estimated that 25% of all accidents are estimated that 25% of all accidents are caused by driver distractions. Automotive caused by driver distractions. Automotive technology is being developed everyday to technology is being developed everyday to make our lives on the roads much safer. make our lives on the roads much safer. Vehicle Skid Control is one such instanceVehicle Skid Control is one such instance

REFERENCES:-

1.www.audidrivingexperience.com2.www.howstuffworks.com3. www.edufive.com/seminartopics.html4.Sing Harbans,The Automobile,1st edition5.www.lexus.com