23-09-2016, 03:36 PM
1455911839-AUTOMATICHEADLIGHTDIMBRIGHTCONTROLLER.doc (Size: 181.5 KB / Downloads: 6)
Synopsis
As for Indian road transport scenario is concerned, accidents are becoming a day to day cause an attempt has been made in this project to reduce such mishaps.
Introduction
Car safety is the avoidance of automobile accidents or the minimization of harmful effects of accidents, in particular as pertaining to human life and health. Special safety features have been built into cars for years, some for the safety of car's occupants only, and some for the safety of others.
Working Operation
The sensor is fixed in front of the vehicle, so that it senses the any obstacle in front of the vehicle. It senses the obstacle and giving control signal to the control unit. The control unit activates the dim light automatically. This operation is called “Automatic head light dim/bright control”.
Advantages
• To provide smooth ride for the motorist.
• To provide mind free ride for the motorist.
• To provide the nation with an accident free roads.
• Low Cost Automation Project
Disadvantages
• Additional Cost is required.
Applications
• This system can be used in both light moving vehicles such as two wheelers as well as in heavy moving vehicles such as buses and trucks etc.
• This system can be implemented in institutional vehicles, taxis, driving school vehicles, etc.
Need for Automation
Automation can be achieved through computers, hydraulics, pneumatics, robotics, etc., of these sources, pneumatics form an attractive medium for low cost automation. Automation plays an important role in automobile.
Nowadays almost all the automobile vehicle is being atomized in order to product the human being. The automobile vehicle is being atomized for the following reasons.
• To achieve high safety
• To reduce man power
• To increase the efficiency of the vehicle
• To reduce the work load
• To reduce the vehicle accident
• To reduce the fatigue of workers
• To high responsibility
• Less Maintenance cost
Types of Sensors
Sensors
A sensor is a transducer used to make a measurement of a physical variable. Any sensor requires calibration in order to be useful as a measuring device. Calibration is the procedure by which the relationship between the measured variable and the converted output signal is established.
Care should be taken in the choice of sensory devices for particular tasks. The operating characteristics of each device should be closely matched to the task for which it is being utilized. Different sensors can be used in different ways to sense same conditions and the same sensors can be used in different ways to sense different conditions.
Types of Sensors
Passive sensors detect the reflected or emitted electro-magnetic radiation from natural sources, while active sensors detect reflected responses from objects which are irradiated from artificially generated energy sources, such as radar. Each is divided further in to non-scanning and scanning systems.
A sensor classified as a combination of passive, non-scanning and non-imaging method is a type of profile recorder, for example a microwave radiometer. A sensor classified as passive, non-scanning and imaging method, is a camera, such as an aerial survey camera or a space camera, for example on board the Russian COSMOS satellite.
Sensors classified as a combination of passive, scanning and imaging are classified further into image plane scanning sensors, such as TV cameras and solid state scanners, and object plane scanning sensors, such as multi-spectral scanners (optical-mechanical scanner) and scanning microwave radiometers.
An example of an active, non-scanning and non-imaging sensor is a profile recorder such as a laser spectrometer and laser altimeter. An active, scanning and imaging sensor is radar, for example synthetic aperture radar (SAR), which can produce high resolution, imagery, day or night, even under cloud cover. The most popular sensors used in remote sensing are the camera, solid state scanner, such as the CCD (charge coupled device) images, the multi-spectral scanner and in the future the passive synthetic aperture radar.
Characteristics of Optical Sensors
Optical sensors are characterized specified by spectral, radiometric and geometric performance. The spectral characteristics are spectral band and band width, the central wavelength, response sensitivity at the edges of band, spectral sensitivity at outer wavelengths and sensitivity of polarization.
Sensors using film are characterized by the sensitivity of film and the transmittance of the filter, and nature of the lens. Scanner type sensors are specified by the spectral characteristics of the detector and the spectral splitter. In addition, chromatic aberration is an influential factor. The radiometric characteristics of optical sensors are specified by the change of electro-magnetic radiation which passes through an optical system.
They are radiometry of the sensor, sensitivity in noise equivalent power, dynamic range, signal to noise ratio (S/N ratio) and other noises, including quantification noise. The geometric characteristics are specified by those geometric factors such as field of view (FOV), instantaneous field of news (IFOV), band to band registration, MTF, geometric distortion and alignment of optical elements. IFOV is defined as the angle contained by the minimum area that can be detected by a scanner type sensor. For example in the case of an IFOV of 2.5 milli radians, the detected area on the ground will be 2.5 meters x 2.5 meters, if the altitude of sensor is 1,000 m above ground.
a. Range
This refers to the minimum and maximum change in input signal to which the sensor can respond. The sensor should posses a wide operating range.
b. Response
The sensor should be capable of responding to change in the sensed variable in minimum time. Ideally, the response should be instantaneous.
c. Accuracy
The accuracy of the measurement should be as high as possible. The output of the sensing device should properly reflect the input quantity being measured or sensed.
d. Sensitivity
It refers to the change in the output exhibited by the sensor for a unit change in input. The sensitivity should be as high as possible.
e. Linearity
The sensory device should exhibit the same sensitivity over its entire operating range.
The following are the other considerations:-
1. The device should not disturb nor have any affected upon the quantity it sensors or measures.
2. The devices should be suitable for the environment in which it is to be employed.
3. Ideally, the devices should include isolation from receiving excess signals or electrical noise that could give rise to the possibility of miss operation or damage of the sensors.
4. Also important are the physical size, cost and ease of operation.
Components and Description
The major components of the “automatic dim/bright controller and engine overheating arrangement” are follows
• LDR Sensor
• Frame Stand
• Battery
• Head light and its arrangement
• Relay
1. LDR Sensor
This is fixed to the front side of the frame stand. In this circuit are having one LDR sensor and control unit.
2. Heat Sensor Unit
The step down transformer is used to convert the 230Volt A.C to 12 Volt A.C voltages. The full wave rectifier circuit is used to rectify the A.C sin wave. In our circuit Heat Sensor is used as a sensor unit. The resistance of the Heat Sensor is changes depend upon the Temperature or fire. The OP-AMP 324 IC is used as a comparator. The comparator is giving the output voltages depends upon the two input voltage values.
3. Frame Stand
The whole parts of our projects are fixed to the frame stand with the help of suitable arrangement. This made upof Mild Steel Materials.
4. Battery
Introduction
In isolated systems away from the grid, batteries are used for storage of excess solar energy converted into electrical energy. The only exceptions are isolated sunshine load such as irrigation pumps or drinking water supplies for storage. In fact for small units with output less than one kilowatt. Batteries seem to be the only technically and economically available storage means. Since both the photo-voltaic system and batteries are high in capital costs. It is necessary that the overall system be optimized with respect to available energy and local demand pattern. To be economically attractive the storage of solar electricity requires a battery with a particular combination of properties:
1. Low cost
2. Long life
3. High reliability
4. High overall efficiency\
5. Low Discharge
Minimum maintenance
a. Ampere hour efficiency
b. Watt hour efficiency
We use lead acid battery for storing the electrical energy from the solar panel for lighting the street and so about the lead acid cells are explained below.
Lead Acid Cell
Where high values of load current are necessary, the lead-acid cell is the type most commonly used. The electrolyte is a dilute solution of sulfuric acid (H₂SO₄). In the application of battery power to start the engine in an auto mobile, for example, the load current to the starter motor is typically 200 to 400A. One cell has a nominal output of 2.1V, but lead-acid cells are often used in a series combination of three for a 6-V battery and six for a 12-V battery.
Construction
Inside a lead-acid battery, the positive and negative electrodes consist of a group of plates welded to a connecting strap. The plates are immersed in the electrolyte, consisting of 8 parts of water to 3 parts of concentrated sulfuric acid. Each plate is a grid or framework, made of a lead-antimony alloy. This construction enables the active material, which is lead oxide, to be pasted into the grid. In manufacture of the cell, a forming charge produces the positive and negative electrodes. In the forming process, the active material in the positive plate is changed to lead peroxide (pbo₂). The negative electrode is spongy lead (pb). Automobile batteries are usually shipped dry from the manufacturer. The electrolyte is put in at the time of installation, and then the battery is charged to from the plates.
With maintenance-free batteries, little or no water need be added in normal service. Some types are sealed, except for a pressure vent, without provision for adding water.
The construction parts of battery are shown in figure.
5. Dim/Bright Light
The dim and bright light is fixed to the frame stand by suitable arrangement. It having three wires they are given bellow.
Wire 1 - Common Wire
Wire 2 - Bright Light
Wire 3 - Dim Light
6. Relay
A relay is nothing but a switch mostly switches are manually operated type. But the operations has not sufficient in ON and OFF purpose, it has many problems. So we are used automatically operated switches it is worked based on the voltage across the relay coil, an relay consist of an relay coil one pole two contact the pole is a movable one.
It is moved to new position by means of voltage is applied to the relay coil. The pole is normally closed contact and another contact is normally opened contact. The supply is available across the relay coil, then the normally opened contact is closed and normally closed contact opened. The above explanations are suitable for single pole and double through relay. The contacts are used to following of the current.
The various current ratings are available. The current rating is not available in the market then we are assuming the total current. But the relays are not used in very high currents rating. Because of arcing at the time of contacts is opened. The relay contacts are periodically checkup is required. The operations will not be followed. So the contact is damaged on the continuous condition may gets damaged the contact, due to the heat.
Working Principle
The Solar panel output is stored in a 12 volt lead-acid battery. The solar panel giving the D.C output of 12 volt at any condition. The battery gives the input power supply of the sensor unit. In our circuit LDR is used as a sensor unit. The resistance of the LDR is changes depend upon the light or fire intensity. The OP-AMP 324 IC is used as a comparator. The comparator is giving the output voltages depends upon the two input voltage values.
In our project one input voltage (Reference Voltages) is given to the PIN number 2 (- ive pin) of 324 IC from the variable resistor (10 K Ohm). The LDR output is given to the OP-AMP pin number 3 (+ ive pin). The LDR light dependent resistor is varying resistance with light intensity. This will be mostly linear to the light intensity. During the darkness the resistance of LDR shoots up to Meg ohm ranges. When LDR is illuminated by means of the sunlight, the resistance of LDR suddenly decreases (below 10 kilo ohm).
At Normal Condition
In normal condition the Resistance of the LDR is high. The voltages applied to the non-inverting terminal (+ ive) is low when compared to the inverting terminal voltages (- ive). In that time, the OP-AMP output is –Vsat. (I.e -12 Volt). The transistor and relay are in “OFF” condition. In that condition, the bright light is in “ON” condition.
At Abnormal Condition
In Abnormal condition the Resistance of the LDR is low due to intensity of the light or fire. The voltages applied to the non-inverting terminal (+ ive) is high when compared to the inverting terminal voltages (- ive). In that time, the OP-AMP output is +Vsat. (I.e +12 Volt). The transistor and relay are in “ON” condition. In that time, the bright light is in “OFF” condition, at the same time dim light is in “ON” position.
Advantages
• Low cost automation project.
• Free from wear adjustment.
• Less power consumption
• Operating Principle is very easy.
• Installation is simplified very much.
• Less time and more profit.
• Sensor cost is low due to LDR sensor
Applications and Disadvantages
Application
• Four wheeler application
• Two Wheeler Application
Disadvantages
• This circuit detects fire also.
• Additional cost required for automation
• This circuit senses the sun light also.