Wednesday, June 8, 2011

wireless sensor network project



In present world, where accidents have become more a day to day happening .It is high time that we come up with a plan to suppress it down. Our paper concentrates on how these daunting accidents which has great toll on valuable lives be curtailed .In India; we don’t have a complicated system which could facilitate to control the accidents. So we have a taken an initiative to control the dreadful accidents, which is at soaring rates at present by means of this paper.
 Our paper is about the prevention of accidents in case of bent roads where most accidents is suspected to happen as in this case vehicle on one side  ignorant about the vehicle coming on the other side. In this paper, we instill awareness in the driver of vehicle coming on one side of the road about the speed and type of other side vehicle of a bent road and make him cautious about the dangers befall him.  
In this paper we have used wireless sensors to demonstrate our idea. Wireless Sensors being a novel concept we really suppose this will help us to transcend our idea. We really presume that this paper will really help in reducing the atrocious accidents which takes a heavy toll on lives.

This project been implemented in bent roads where accidents are common will greatly help in preventing the accidents in a great way.


 Sensor node a part of the wireless sensor, which consists of a processor,
·        A radio and processor,
·        A magnetometer,
·        A battery and
·         A cover for protection from the vehicles.

The processor and the radio are located in MICA2DOT, the latest family of Berkeley motes .The microprocessor is Atmel ATmega128L with 128kB of programmable memory and 512kB of data flash memory.
It runs TinyOS, an operating system developed at UC Berkeley, from its internal flash memory.
TinyOS enables the single processor board to run the sensor processing and the radio Communication simultaneously.
The radio is ChipCon CC1000 916MHz, frequency shift keying (FSK) RF transceiver, capable
of delivering up to 40kbps. The RF transmit power can be changed in software.
        There are two HMC1051Z magnetic sensors, based on anisotropic magneto resistive (AMR) sensor technology. To receive one sample, the magnetometer is active for 0.9 msec and the energy spent for taking one sample is 0.9μJ. The magnetometer is turned off between samples for energy conservation.
  The battery is Tadiran Lithium TL5135, with 1.7Ah capacity in a compact size. The
entire unit is encased in a Smart Stud cover, designed to be placed on pavement and able to withstand 16,000 lbs. So the node is protected and can be glued on anywhere on the pavement.


In a communications network, a network node equipped for interfacing with another network node.
In this case Gateway Node is used to receive the signals from the sensor node on one side of the road and to transmit the signal to the sensor node on the other side of the road.It is simply a node
Which can receive the signal from one side and transmit the data to the other side.
We program the gateway node using netc in tinyos according to our need.


The actuator receive signal from the sensor node about the type and speed of the vehicle coming on the other side. The microprocessor processes the data and it switches on a corresponding relay based on the information supplied by the sensor node.
For ex:  a lorry or heavy locomotive coming a red light will be switched on making the driver cautious about the presence of a heavy locomotive on the other side.

The sensor detects distortions of the Earth’s field caused by a large ferrous object like a vehicle.
Such a vehicle can be modeled by a composite of many dipole magnets. Since

the distortion depends on the ferrous material, its size and orientation, a magnetic signature is induced  corresponding to the vehicle’s shape and configuration.

Based on the distortions produced in the sensor we may detect the speed and the type of vehicle.

These distortions are processed by the processor and based on the magnitude the type of vehicle is found out.
Speed detection:
                     VEHICLE             A                  B
To detect the speed of the vehicle the time when sensor node A and node B suffers distortions
is processed by the  processor in the GATEWAY node and the speed is found out by the simple formulae

 Since the distance between the sensor node A and sensor node B is constant and
The time when sensor node A and sensor node B suffer distortions, this information is send to the GATEWAY Node which calculates the time difference and calculates the speed of the vehicle using the formulae specified above. This information is then send to the sensor Node on the other side which excites the actuator which switches on a particular light based on the speed and type of vehicle.

The following graph shows the excitation in the output of the node A and node B when a vehicles passes across

Likewise the speed is detected and the type of vehicle is also detected and consequently a particular output signal is triggered by the actuator based on the data supplied to it.


Since the communication is wireless it is must to write protocol to control the communication between the sensor nodes and the GATEWAY Nodes.
In a sensor node, battery energy is mostly consumed by the radio. Therefore, the networks

Communication protocol, which determines how the radios are operated, has a decisive influence
on battery lifetime. Existing MAC protocols fall into one of two categories: random
Access and time division multiple access (TDMA).
In this paper we use random access  since the information must be passed to the gate way node whenever there is a vehicle.But at other times it is said to be inactive state on the verge of conserving power.Once the information passed to the gateway node ,this information is processed and  passed on to the sensor node located on the other side of the road which as a result produces the output signal.

Salient Features:

  • The process is wireless so no need of placing wires under the ground.
  • Till date in india we don’t have a complicated system to curb down the accidents.
  • This can be installed in every bent roads where accidents are frequent.
  • There is no need of maintenance since the work can be automated with the help of protocols and programs written in Netc in TinyOS environment.
  • This will greatly help in reducing the soaring accident rates .


·         This paper can be extended so that vehicles may receive the signals directly from the sensor node than viewing as signal on the side of the road.
·         A camera can also be embedded on the bottom of the road so that the reg no of the vehicle can be picturised and corresponding speed can be stored in the database along with it.
·         It can be also extended to be used for overspeed prevention by informing the traffic department about the vehicle no which have exceeded the speed limit of that locality.

1.       Networking Wireless Sensors 
                    by Bhaskar Krishnamachari

2.       Wireless Sensors and Instruments: Networks, Design, and Applications
by Halit Eren





I Posted it  just to give a idea regarding the sensor network projects.Ki ndly don't imitate it in any of the paper presentations.
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