This document discusses an anti-lock braking system (ABS). It begins with an introduction to ABS and then outlines the objectives and components of the system. The objectives are to reduce stopping distance, improve stability, and maintain steerability during braking. The key components are the master cylinder, wheel speed sensors, and hydraulic control unit. The document then presents mathematical models of vehicle dynamics, wheel dynamics, and the overall ABS system model in Simulink. Simulation results show that ABS is able to regulate wheel slip to reduce stopping distance and maintain control compared to conventional braking without ABS.
An anti-lock braking system or anti-skid braking system (ABS) is an automobile safety system that allows the wheels on a motor vehicle to maintain tractive contact with the road surface according to driver inputs while braking, preventing the wheels from locking up (ceasing rotation) and avoiding uncontrolled skidding.
An anti-lock braking system or anti-skid braking system (ABS) is an automobile safety system that allows the wheels on a motor vehicle to maintain tractive contact with the road surface according to driver inputs while braking, preventing the wheels from locking up (ceasing rotation) and avoiding uncontrolled skidding.
Linear Control Technique for Anti-Lock Braking SystemIJERA Editor
Antilock braking systems are used in modern cars to prevent the wheels from locking after brakes are applied. The dynamics of the controller needed for antilock braking system depends on various factors. The vehicle model often is in nonlinear form. Controller needs to provide a controlled torque necessary to maintain optimum value of the wheel slip ratio. The slip ratio is represented in terms of vehicle speed and wheel rotation.
In present work first of all system dynamic equations are explained and a slip ratio is expressed in terms of system variables namely vehicle linear velocity and angular velocity of the wheel. By applying a bias braking force system, response is obtained using Simulink models. Using the linear control strategies like PI-type the effectiveness of maintaining desired slip ratio is tested. It is always observed that a steady state error of 10% occurring in all the control system models.
Vehicle safety system
it covers
hydraulic brakes
working of drum ,disk brakes
abs
airbags
ESP/ESC(electronic stability programme)
future trends in safety systems
cruise control
ACC
Linear Control Technique for Anti-Lock Braking SystemIJERA Editor
Antilock braking systems are used in modern cars to prevent the wheels from locking after brakes are applied. The dynamics of the controller needed for antilock braking system depends on various factors. The vehicle model often is in nonlinear form. Controller needs to provide a controlled torque necessary to maintain optimum value of the wheel slip ratio. The slip ratio is represented in terms of vehicle speed and wheel rotation.
In present work first of all system dynamic equations are explained and a slip ratio is expressed in terms of system variables namely vehicle linear velocity and angular velocity of the wheel. By applying a bias braking force system, response is obtained using Simulink models. Using the linear control strategies like PI-type the effectiveness of maintaining desired slip ratio is tested. It is always observed that a steady state error of 10% occurring in all the control system models.
Vehicle safety system
it covers
hydraulic brakes
working of drum ,disk brakes
abs
airbags
ESP/ESC(electronic stability programme)
future trends in safety systems
cruise control
ACC
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
2. INTRODUCTION
ANTILOCK BRAKING SYSTEM 2
• Anti-lock braking system (ABS) is an automobile safety system that allows
the wheels on a motor vehicle to maintain tractive contact with the road surface
according to driver inputs while braking, preventing the wheels from locking up
and avoiding uncontrolled skidding.
• ABS generally offers improved vehicle control and decreases stopping distances
on dry and slippery surfaces.
• ABS modulates the brake line pressure independent of the pedal force, to bring
the wheel speed back to the slip level range that is necessary for optimal
braking performance.
3. PROJECT OUTLINE
ANTILOCK BRAKING SYSTEM 3
• Objectives of ABS
• Components of ABS
• Working of ABS
• Mathematical model
• System model
• Results
• Conclusion
• References
4. OBJECTIVES OF ABS
ANTILOCK BRAKING SYSTEM 4
• To reduce stopping distance
1. The road surface type and conditions can be inferred from the vehicle's
braking pressure, wheel slip measurements, and deceleration rate
comparisons.
2. The wheel slip is regulated so that the road adhesion coefficient is
maximized. By keeping all of the wheels of a vehicle near the maximum
friction coefficient, an antilock system can attain maximum fictional
force
3. In turn, this strategy leads to the minimization of the vehicle stopping
distance.
5. ANTILOCK BRAKING SYSTEM 5
• Stability
1. A locked-up wheel generates a reduced braking force, smaller than the peak
value of the available adhesion between tires and road. A locked-up wheel
will also lose its capability to sustain any lateral force. This may result in the
loss of vehicle stability.
2. The basic purpose of a conventional ABS system is thus to prevent any
wheel from locking and to keep the longitudinal slip in an operational range
by cycling the braking pressure.
6. ANTILOCK BRAKING SYSTEM 6
• Steerability
1. Good peak frictional force control is necessary in order to achieve
satisfactory lateral forces and, therefore, satisfactory steer-ability.
2. If an obstacle appears without warning, emergency braking may not be
sufficient. When the wheels are locked, car no longer respond to the driver’s
steering intention.
3. With ABS car remains steerable even during emergency braking, and thus the
obstacle can be safely avoided.
7. ANTILOCK BRAKING SYSTEM 7
• Power booster and master cylinder assembly
1. It is activated when the driver pushes down on the brake pedal. The master
cylinder transforms the applied pedal force into hydraulic pressure which
is transmitted simultaneously to all four wheels.
2. It provides the power assistance required during braking.
• Wheel sensor unit
1. Speed sensors are comprised of a magnet wrapped in a coil and a toothed
sensor ring. An electrical field given off by the contact between the magnet
and the toothed ring creates a AC voltage.
2. The voltage frequency is directly proportional to the wheel's rotational
speed.
3. It monitors the rotational speed of the wheel and transmits this data to the
ABS control module.
8. WORKING OF ABS
ANTILOCK BRAKING SYSTEM 8
• If a wheel-speed sensor signals a lock up - the ECU sends a current to the
hydraulic unit. This energizes the solenoid valve. The action of the valve
isolates the brake circuit from the master cylinder. This stops the braking
pressure at that wheel from rising, and keeps it constant. It allows wheel
velocity to increase and slip to decrease.
• When the velocity increases, ECU re-applies the brake pressure to restrict
the wheel slip to a particular value.
• Hydraulic control unit controls the brake pressure in each wheel cylinder
based on the inputs from the system sensor. This in result controls the wheel
speed.
9. MATHEMATICAL MODEL
ANTILOCK BRAKING SYSTEM 9
• Wheel slip:
When the braking action is initiated, a slippage between the tire and the
contacted road surface will occur, which make the speed of the vehicle to be
different from that of the tire.
• The longitudinal slip is defined as
𝑆 =
𝑉𝑐𝑜𝑠𝛼 − 𝜔𝑅𝑤
𝑉𝑐𝑜𝑠𝛼
The side slip angle is
𝛼 = 𝑡𝑎𝑛−1 𝑉𝑠𝑦
𝑉𝑥
Force and velocity components on tyre
10. ANTILOCK BRAKING SYSTEM 10
• Vehicle Dynamics
According to Newton's second law, the equation of motion of the
simplified vehicle can be expressed by,
𝑚𝑡𝑉 = −𝐹𝑡 − 𝐹𝑎
The road friction force is given by Coulomb law
𝐹𝑡 = 𝜇𝑁
The total mass of the quarter vehicle can be written as
𝑚𝑡 = 𝑚𝑡𝑖𝑟𝑒 +
𝑚𝑐
4
Thus, the total normal load cm be expressed by
𝑁 = 𝑚𝑡𝑔 − 𝐹𝑙
𝐹𝑙 is the longitudinal weight transfer load due to braking
12. ANTILOCK BRAKING SYSTEM 12
• Wheel dynamics
According to Newton's second law, the equation of motion at wheel
level for the rotational DOF is given by,
𝐽𝑤𝜔 = −𝑇𝑏 + 𝐹𝑡𝑅𝑤
14. SYSTEM MODEL
ANTILOCK BRAKING SYSTEM 14
Assumption: Only a linear model was considered and does not include actual road
conditions. The system here is modelled only for straight line braking.
15. INPUT PARAMETERS FOR SIMULINK MODEL
ANTILOCK BRAKING SYSTEM 15
Gravitational constant 𝑔 = 32.18 𝑓𝑡/𝑠2
Initial velocity of vehicle 𝑣0 = 88 𝑓𝑡/𝑠
Wheel Radius 𝑅𝑟 = 1.25 𝑓𝑡
Mass of vehicle 𝑚 = 50 lbs
Maximum Braking Torque 𝑇𝑏𝑚𝑎𝑥
= 1500 𝑙𝑏𝑓 ∗ 𝑓𝑡
Hydraulic Lag 𝑇𝐵 = 0.01 𝑠
Moment of Inertia 𝐽𝑤 = 5 𝑓𝑡4
22. CONCLUSION
ANTILOCK BRAKING SYSTEM 22
• It is inferred that ABS improves the braking performance.
• The stopping distance after using ABS system has considerably reduced.
• The error in slip and desired slip is used to manipulate brake pressure in brake
cylinder.
23. REFERENCES
ANTILOCK BRAKING SYSTEM 23
• Tianku Fu,“Modelling and performance analysis of ABS system with non-linear control”,
2000.
• Tobias Eriksson,“Co-simulation of full vehicle model in Adams and anti-lock brake system
model in Simulink”, 2014.