Defence alarm system gathers dust in laboratory

The low cost system can detect intrusion in border areas, which is difficult to monitor by line-of-sight implements or patrolling personnel.It can alert the authorities through discontinuous beeps if a single intruder crosses the border. In case of vehicles or a group of people running across the border, it emits a continuous noise.

The knowhow was transferred to Indian Telephone Industries ITI, Naini, for commercialisation. But unfortunately, there are no takers, said the scientists.

quot;Though the vibration sensor-based system has been demonstrated successfully to the Border Security Force BSF and Indian Army several times, nobody has come forward to take it,quot; they said.

Last month, the BSF tried the device at Bhuj region of Gujarat, the scientists said, claiming that it was a success, like the previous times. Surveillance in Kashmir border can be made easier and better with the system, as up to 15 sensors could be monitored from a receiving point situated on a hill-top, the defence scientists said.

It was demonstrated in Barmer and Jaisalmer in Rajasthan, Kutch region in Gujarat and the Punjab border. It had not been tested in Kashmir Valley, though demonstration dates were fixed several times in the past, only to be cancelled at the last moment, they said. The performance of the system is weather-independent. It sleeps in the absence of intrusion activity and wakes up in the presence of targets.

Called Remotely Activated Acoustic Warning System RAAWS, it can narrow down the location within a range of 10-50 metres, depending upon the soil condition. It runs on re-chargeable 12 volt nickel-cadmium batteries.The six-inch long pyramidal sensor needs to be grounded in an inverted fashion behind a bush or a sand dune for camouflage.

The sensors are connected to a receiving unit placed a few kilometres away which can monitor activities around each sensor.

The system, that costs about Rs five lakh, consists of vibration sensors and receivers. Vibration generated by moving personnel or a vehicle is detected first by the sensor which filters and amplifies the signal and converts it into a detectable electrical signal.

As an important civilian spin-off of this technology, the scientists have developed an unmanned railway level crossing warning system which also acts by picking up the vibrational signal generated by a moving train.

It can detect approaching trains sufficiently in advance to generate an alarm in the form of a sharp hooting sound and an intense flashing light to attract attention.

quot;There are lakhs of unmanned railway level crossings where the system can be employed to prevent accidents,quot; they added.