26-05-2014, 11:16 AM
Automatic Acceleration Control and Braking System (AACBS)
Automatic Acceleration.docx (Size: 76.87 KB / Downloads: 30)
ABSTRACT
Vehicle technology has increased rapidly in recent years, particularly in relation to braking and sensing systems. With alarming increase in road accidents being recorded in large numbers every year, increasing demand for electronic stability control(ESC), sensors to allow traction control(TC), brake assist(BA), adaptive cruise control(ACC) and electronic brake force distribution is increasing.
Major drawback in existing system:
1) On viewing an obstacle at certain nearer distance, existing braking control systems tend to apply sudden brakes without decelerating the vehicle.
2) Such a performance is not suitable for vehicle traffic conditions in India.
3) Collision, Bodily Injury, Property damage.
Problem statement:
The automatic acceleration control system includes three major components: 1) a RADAR 2) microcontroller and 3) a gear and braking system. The radar is activated only when the vehicle’s speed limit approaches 60kmph and transmits signals that reflect back from an obstacle, probably a vehicle in roadway, by which the approximate distance is calculated and sent as an input to the microcontroller. As per programmed in controller, the gear and braking system gets activated in response to the reducing distance of the approaching obstacle, thereby decelerating the vehicle when the obstacle is 500m apart from the vehicle under control. And ultimately the brake is applied when the obstacle crosses a distance limited by the program given to the controller.
Problem solution:
One way to measure the distance to an object is to transmit a short pulse of radio signal (electromagnetic radiation) and measure the time it takes for the reflection to return. The distance is one-half the product of the round trip time (because the signal has to travel to the target and then back to the receiver) and the speed of the signal. Since radio waves travel at the speed of light, accurate distance measurement requires high-performance electronics. Through the use of a duplexer, the radar switches between transmitting and receiving at a predetermined rate.
ECUs use a microprocessor which can process the inputs from the engine sensors in real-time. An electronic control unit contains the hardware and software. The microprocessors in the ECU will receive input from the sensor that is placed in the throttle pedal. Based on the extent to which the throttle is pressed the micro processor will send electrical signals which will control the carburettor and fuel injection system. By interrupting this routine and generating instructions which will perform the deceleration operation the speed of the vehicle can be controlled.
SYSTEM ARCHITECTURE:
Brake Sensors:
Sensor controlled systems have become an integral part of today’s automobile. A multitude of electro-mechanical devices have become better refined and more efficient with their application. Travel sensors are a core component of electric brake pedals, which are required for efficient braking systems in hybrid and electric vehicles. These pedals record the driver's desired level of braking, which the systems then implement electrically, hydraulically, or using a combination of the two.
The measurement principle behind the Brake sensor is based on a Hall sensor that records the magnetic vector of a magnetic field. The magnetic field is generated using a magnetic circuit, which takes into account the design requirements of numerous braking systems and reports linear and rotational motion to the Hall sensor. Also there is a brake fluid sensor located in the reservoir at the master cylinder. When the brake fluid is low it will turn the light on.
Operation of Radar:
The following figure shows the operating principle of a primary radar set. The radar antenna illuminates the target with a microwave signal, which is then reflected and picked up by a receiving device. The electrical signal picked up by the receiving antenna is called echo or return. The radar signal is generated by a powerful transmitter and received by a highly sensitive receiver.
CONCLUSION:
This paper represents design and implementation of an Automatic Acceleration Control and Braking System using RADAR .Once achieved this would not only saves the lives of people also gain profit as well. Introducing AACBS to automobiles (especially cars) will definitely change the view of vehicle technology. The casualty reduction potential in this situation was greatly increasing and if fitted to all cars it would likely to have a fatality saving potential .Overall it is found that AACBS is likely to be very highly effective safety measure in terms of both casualty reduction and benefit to cost ratio in the near future if implemented.And we hereby declare that this project is the results of our own research except
as cited in references.