17-06-2010, 01:01 PM
[attachment=3774]
AUTHORS:
R.Sridevi,
&
E.Prasoona,
Final year, B.E (ECE)
Sir C.R.R COE, Eluru.
SIR C R REDDY COLLEGE OF ENGINEERING, ELURU
Department of Electronics & Communications Engineering
VEHICLE MONITORING AND CONTROL SYSTEM USING MICROCONTROLLERS
ABSTRACT:
It is observed that most of the accidents occur due to the driverâ„¢s ignorance of traffic and safety rules. It is a practice for the drivers to drive the vehicle beyond permitted limits. Depending on the terrain, and other conditions, speed restrictions may be imposed on drivers from time to time. Therefore, a system monitoring the speed and other desired vehicle parameters can be installed in the vehicle to warn the driver appropriately and intervene to control if necessary.
One may not know the instantaneous position of a vehicle and itâ„¢s arrival time. Generally, the truck operators depend on intermittent telephone calls made by the drivers.To overcome such problems, an automatic monitoring system can be established with monitoring stations located at important major junctions, cities through which the vehicles ply. As the vehicle approaches a monitoring station, it has to automatically identify itself and upload critical data about the vehicle and operating conditions. The monitoring station can send modified control parameters and guidelines to the vehicle driver. For this purpose, we need a RF (radio frequency) transceiver system.
In general, vehicle monitoring, tracking and such activities are done using separate systems and they require some mechanical force as input. Speed is monitored using speedometer and for controlling mechanical force is required to decelerate it. Fuel level monitoring, proximity detection, battery monitoring, etc requires separate system. This paper presents a micro-controller-based control and monitoring system. Normally we need to use extra RF building blocks to provide RF page link increasing the system complexity. In such cases, a PSoC (Programmable System-On-Chip) micro-controller can be used in place of conventional approach. In this system, initially a building block can be used to monitor the status of vehicle and store it in memory. Then, same building block will be configured as a receiver and the system looks for an approaching monitoring station. The same building block can be configured as transmitter and used to upload the vehicle information.
A PSOC based system is versatile in that it offers dynamic reconfigurability in the same IC package.
ORGINASATION:
The nature of human being is to lead his life in most comfortable way. Our paper presents an idea of such system, which is most compact and is portable so to land it at any place of the vehicle. However, such techniques are being implemented in many other conventional means but, due to the advent of PSOC & SOCâ„¢S (Programmable system on chip & system on chip). The systems are being smaller and smarter.
Our paper is organized as follows. In section I, it deals with introduction of the system. In section II, it deals with operation of the system. In section III, it deals with various applications of the system. Finally section IV, deals with conclusion of our presentation.
I.INTRODUCTION:
The vehicle monitoring system can be easily implemented by using PSoC (Programmable system-on-chip). As said above, it can be dynamically reconfigured by suitably programming at the run time. However, this programming can be done by using high level language such as 'C' with which most of the hardware designers would be familiar. This makes ËœCâ„¢ the natural language for system-on-chip.
An instant tracking system is needed for vehicles carrying inflammable fuels, explosives, etc. in such cases GPS (Global Positioning System) can be used more effectively. This is going to be costlier. This paper presents cost effective and more compact equipment for various applications. An automatic monitoring system for vehicles can be established with monitoring stations located at major junctions, cities through which the vehicle ply. As the vehicle approach a monitoring station, it has to automatically identify itself and upload critical data about the vehicle and operating conditions such as temperature, speed, fuel, battery indication, coolant level etc.
FEATURES:
Some of the important features of the PSoC are follows:
1. Powerful Harvard architecture processor.
2. Advanced peripherals.
3. Flexible on-chip memory.
4. Precision, programmable clocking.
5. Programmable pin configuration.
6. Additional system resources.
7. Complete development tools.
II.OPERATION:
The typical parameters of a vehicle are temperature, speed, fuel, battery indication, coolant level etc. These are measured by appropriate sensors, followed by signal processing block and are given to ADC block that is an internal block of PSOC. The desired parameters are sampled at regular interval; suitable actions are taken and are stored in memory for later reference.
Generally the system acts as a receiver. This consists of a RF preamp, demodulator. These blocks, but for RF preamp, are readily provided by PSOC. The output of demodulator is fed to the UART, which is configured as a receiver. The system looks for an approaching monitoring station. When it detects the monitoring station, UART is configured as transmitter and is used to convert data into serial form, then modulated using digital modulation techniques, followed by a RF amplifier, to upload the vehicle information. The only external blocks that are used in the system are RF amplifiers and power amplifiers. Therefore the choice of PSOC reduces component count in the circuit.
III.APPLICATIONS:
a.)ENGINE SPEED MONITORING & CONTROL SYSTEM:
The crankshaft is applied with a reflective coating and at the middle a strip of black absorbing material is placed. Light is projected on to this rotating shaft. The light is reflected by the reflecting surface and is absorbed by the black-colored strip. The reflected light is sensed by photo sensor, followed by signal amplifier. The signal is then applied to schmith trigger and corresponding pulses are obtained. They are fed to a counter. These blocks are readily available in PSOC.
The Engine speed is monitored once in a second and converted to RPM, and displayed in the display unit. When the Engine speed exceeds a predefined value, the monitor intervenes, and activates a motor to apply the brakes. In this way the speed is automatically limited to a predefined value.
b.)FUEL LEVEL MONITORING:
The fuel level can be monitored by using a non-conducting, non-contact measurement system using ultra sonic waves. The system consists of a ultra sonic transponder. The transponder is fixed at the top of the fuel tank. Ultra sonic signals are sent in the downward direction. These waves are reflected from the fuel surface and the receiver receives the reflected signals. The time elapsed, in receiving the reflected ray since the transmission of signal, gives the total distance traveled by the rays. By evaluating the simple mathematical expressions we can easily calculate the fuel level in the fuel tank. This information is stored in Memory and used to warn the driver about Fuel level.
C.)COLLISION DETECTION SYSTEM:
One of the major problems in road transport is Head on Collisions, in which lives are lost. To avoid or minimize collisions, the distance between this vehicle and neighboring vehicles is to be monitored. As the gap reduces once again the driver is to warned. For this an Ultra sonic proximity sensor can used. This consists of ultra sonic transmitter and receiver. The Ultra sonic signals are transmitted at regular intervals. These signals, upon falling on approaching vehicle, would be reflected. The reflected signal is received by Receiver circuitry, and the time for receiving the reflecting the signal is calculated. The time reduces for an approaching vehicle. This can be checked by a program, which alerts the driver. All the building blocks such as Signal amplifiers are readily provided by PSoC.
d.)TEMPERATURE MONITOR:
One major area that troubles the people is the engine. If the heat generated is not removed and the engine is not cooled, in no time the engine starts to err before it comes to grinding halt. It is better to use the thermal relays such as thermistors. Here a thermistor is used to form a resistor divider network and the junction voltage is fed to a voltage amplifier followed by ADC. Then the digitized value is used by the program to check for the limits and suitable warning is issued to driver. If any further rise of temperature is detected, then the monitor can cutoff fuel to engine and apply brakes, forcing the vehicle to stop.
In this all the blocks, i.e. Voltage amplifier, ADC is available in PSOC, simplifying the implementation
e.)BATTERY MONITOR:
Battery voltage is another major problem auto field. Especially when the battery is completely discharged, it causes problems. A comparator can monitor the battery status. To one input a ref voltage is applied and to the second input battery voltage is applied. If the battery voltage is greater than the reference voltage, the output of op-amp is positive. So the LED glows indicating battery is full. If the battery voltage is less than the reference voltage, output of the op-amp is negative and LED turns off indicating battery is to be charged. This can caution the driver.
IV.CONCLUSION:
The above system can be implemented using traditional designs and approach. But the trend is to embed the systems into the gadgets, which they are controlling. This puts restrictions on designers for space, cost and power consumption. In such cases one can turn to micro controller based designs. The usage of PSOC simplifies design complexities, reduces the size of system greatly and offers a host of peripheral devices that can be dynamically configured and used. It is expected that near future PSOC over takes other micro controllers in the market and systems based on PSOC would be flooding the homes.
V.REFERENCE:
Magazines: IEEE transactions, electronics for you.
Books:
1. The 8051 Micro Controller and Embedded Systems
-Muhammad Ali Mazidi
-Janice Gillispie Mazidi
2. Design with PIC Micro Controller
-John.B.Peatman
3. Micro Controller technology
-Peter Spasov
4. Embedded Micro Controller
-Todd.D.Morton
