24-09-2014, 03:43 PM
Design of Automatic Speed Control System in 4 – Wheelers for Avoiding Accidents Project Report
Automatic Speed Control.pdf (Size: 204.44 KB / Downloads: 182)
ABSTRACT
Many accidents are at least partially caused because of rash driving. This can happen due to
many reasons: poor judgment on the part of the driver, poor driving by the driver. Once the driver has lost
control it is very difficult to drive the vehicle. To avoid rash driving and to prevent losing of valuable property
we need some safety systems in the vehicles. We can make this true by controlling the flow of fuel to the Engine
using sensors and other mechanical arrangements and this can bring the vehicle to the intended course. This
simple system provides safety, and avoids rash driving in highly populated regions.
INTRODUCTION
For avoiding rash driving by drivers, we provide safety systems within the vehicles especially for 4-
wheelers.. The main conclusion of their report is the crucial importance of seat belts and padded dashboards.
Since then many important inventions such as automatic braking, electronic stability control, adaptive cruise
control, traction control systems, antilock braking, etc. Our work is on a same pathway. In this system there is
one power source (battery) as an input, one controlling element (toroidal coil with controlling rod arrangement),
micro controller and small modifications in the already existing conventional designs of S.I & C.I
[b] Description
It is the system, which mainly uses photoelectric sensor, electrical power source and micro-controller
for controlling the vehicle speed. The arrangement of the components used in this system. By using this simple
system we can control automatically the speed of the vehicle. The vehicle will move with designated speed (low
speed) of the control system even though the driver wants to drive the vehicle with high velocities.
Photo Electric Sensor
A photoelectric sensor is a device used to detect the distance, absence, or presence of an object by
using a light transmitter, often infrared. A retro-reflective arrangement places the transmitter and receiver at the
same location and uses a reflector to bounce the light beam back from the transmitter to the receiver[1]. An
object is sensed when the beam is interrupted by the same [1]. Diffuse reflection is the reflection of light from an
uneven or granular surface such that an incident ray is seemingly reflected at a number of angles. It is the
complement to specular reflection. If a surface is completely non-specular, the reflected light will be evenly
spread over the hemisphere surrounding the surface.
MODIFICATIONS IN FUEL CONTROL SYSTEMS
We are giving small modifications to the already existing fuel supply system in S.I. engine and also in C.I.
engine. But these modifications are very small.
2.1 In S.I engine
In this fuel supply system I am just using the control rod movement to force a metering rod element in to the
main jet pipe that will restrict the flow area. So for given pressure depression in the carburetor a decrease in
flow area implies the amount of fuel entering also decreases which eventually reduces the speed of the vehicle.
WORKING
The system will start working only when we applying the brake a number of times. The brake will act
like a switch. When the brake is pressed the circuit will be completed by the battery which will start conducting
the charge, which will be stored in the toroidal coil. Due to high valued resistor in the parallel circuit and low
resistance of coil, 95% of charge will be stored within the coil. This charge will create a magnetic field around
the coil that will pull the controlling rod.[4] This controlling rod movement will be used for controlling the fuel
supply system for varying the fuel rate entering into the combustion chambers.
In case of S.I. engine the controlling rod will force or move another needle, which will obstruct the
flow area in main fuel nozzle so with this effect the quantity of fuel entering will be decreased. It cannot affect
the airflow rate or any other thing; it only reduces the quantity of fuel entered.[5] In case of C.I. engine the
controlling rod movement will be used for rotating the circular ring on fuel induction pump, which will control
the opening of hole through the port, when the hole is opened the fuel will be spilled out.
Due to opening of spill port in circular ring before the actual spill port (due to helical groove
arrangement) the quantity of fuel injected will be varied. It will rotate in opposite direction to that of plunger
rotation. If the controlling rod is moved to a full extent then the quantity of fuel injected will be very small
irrespective of the actual spill port position.Due to opening of brake the circuit will be disconnected with the
battery. During this energy that is stored in the toroidal coil will be discharged through the variable resistor and
the lamp [3]. So there is no power or energy input to the toroidal coil. To discharge all the energy stored within
the coil will take some time due to higher resistance in the path. During this period the system will continuously
control the fuel flow. This time period we can vary by varying the resistance value of the resistor
SALIENT FEATURES OF THE SYSTEM
We used the low voltage battery which is safe to operate and easy to charge
Controlling of force acting on the controlling rod is very easy. It is simply by varying the variable resistor.
Energy consuming device which we are using i.e. a lamp is a less expensive device and it is also used for
giving indication to the driver.
The modifications given for the conventional carburetor or fuel injection pump are very small and simple.
The costs of the system are of very less expense varying from Rs. 1000/- to Rs. 3000/- only.
This system can be more effectively used for heavy duty locomotives and automobiles, which are the main
cause for accidents.
CONCLUSION
Finally we can use this system for S.I. engines, C.I. engines and also for gas engines. We can vary the value of
variable résistance as per our requirements. For buses and Govt. vehicles we will set the resistance to a low
value. So for these vehicles the time for which the system is in an active condition, is very less. So the time for
which the vehicle will move slowly will also be very less.But for Lorries and autos we can use higher values of
variable resistance. So it will take more time to consume the charged energy. These vehicles need more time to
get back the system to its normal state.
So by using this system we can reduce rash driving and accidents up to 35% and we can save many lives and
many valuable properties. We can reduce the rash driving within cities, within the regions of school zones,
villages that are located at the highways and beside the highways.