Good Thinking

Radar system could detect people who fall onto train tracks

Radar system could detect peop...
A new radar system could be used to detect and identify objects that fall onto train tracks (Photo: Nigel Chadwick)
A new radar system could be used to detect and identify objects that fall onto train tracks (Photo: Nigel Chadwick)
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A new radar system could be used to detect and identify objects that fall onto train tracks (Photo: Nigel Chadwick)
A new radar system could be used to detect and identify objects that fall onto train tracks (Photo: Nigel Chadwick)

Although you may never have seen it happen yourself, it isn't all that uncommon for large objects - including people - to fall onto the tracks at subway or railway platforms. While security personnel viewing CCTV feeds will catch some of these accidents, the cameras' shots are sometimes obscured by people, poor lighting, or even the trains themselves. The results can range from lengthy delays in rail service, to fatalities. Now, however, researchers working on a project for the Université Lille Nord de France have developed a system that uses radar to automatically detect and identify objects that fall onto the tracks. When installed at a platform, the system could then shut off power to the tracks, and notify oncoming trains.

The system continuously sends out wideband radio waves, and analyzes their reflections when they're bounced back by a foreign object, via an Automatic Target Recognition procedure. Only the most prominent features of the object's reflected signal are processed, and then compared to a database of known objects.

In a computer simulation, the researchers tested the system using objects such as suitcases, bottles, and the bodies of human adults, adolescents and children. In all cases, it was able to accurately identify the objects. Physical tests were also conducted in an echo-free chamber, in which the radio waves were guided towards two men, a woman, and two pieces of luggage made of different materials. Once again, it was able to differentiate between the subjects.

"We hope these devices will be used in the near future since they are very complementary to existing video systems and have a similar final cost," said Ali Mroué, lead author of a paper on the research. "The complementary use of video and radar systems could lead to low levels of false detection, which is mandatory for this application, and maximize the chance of survival for passengers who have fallen on the line."

The paper was published today in the journal Measurement Science and Technology.

John Potter
Ref: UK only Total Daft, you are not dealing with a sane rational public and ignores children sizes, dogs etc. Only way is to link it to a overhead cctv auto-switching to the Control Desk so ECRO\'s can provide a rational localized switching procedure, limiting the the resultant delays that platform only. Public safety involves much more than the unfortunate individual who might well regain the platform within 2 sec. Note: Discharging the current does not apply the oncoming trains brakes. also Regenerative braking is \"uncontrolled\" and apply\'s current to the tracks. Delays to trains over 30min might well result in passengers de-training. Station staff are \"NOT\" allowed/authorized on the track (see recent dismisal).
A good warning system is nice but I would prefer a good system of vertically open and closing gates that keep people and debris off the tracks. One of the problems with the \'Third rail\' electrical supply system is that if you do fall on the tracks there is only one safe direction to roll out of the way of a train. It would be possible to combine the warning system with a system of high-pressure water or air to clear the tracks of debris, or people to safety.
John Potter
I think you got it Slowburn give the chicken dancers , train skateboarders and other urban gamers a good soaking, experience has shown that only by lawless action does someone \"Fall\" from a platform.
Stay behind the Yellow Line! and \"Control\" your pets and children.
Suggestion: Hand out B.T. Police camera\'s and increase Police presence in evenings also give plat. staff 10% of on-spot Trespass Fines ( £1000 at present ).
Its another devices that will fail after expensive testing (at e.g.Wimbledon) in the U.K. because T.O.s will make it fail, and present a better case to H.M. Inspectorate (more lawyers (usually ten per T.O.)) - ECRO -
The system described above in the article is unnecessary and over-complex.
The problems have already been solved at some train stations around the world by simply adding walls on the edge of the platforms made with a clear perspex pane and automatic doors that open only when a train has arrived and are closed otherwise. Also, you would need an overhead walkway to get to the other side safely and stop people crossing the tracks.
Charles Bosse
Contrary to the above naysaying, I think this is pretty cool and gets us closer to mostly automated rail systems. Of course, I agree that a good first step would be rail and transit companies that gave a dingle or had adequate funding and maintenance (a rail bridge near a previous home looked like it was about to fall apart any day until a train hit a teenager who opted to cross the tracks instead), but I still think this is cool.
I agree with Oztechi. An ounce of prevention is worth a kilogram of cure. Further, people or objects on the tracks will still be at the mercy of how fast a train\'s mass can be brought to a halt, particularly if the incident happens moments before a train arrives.
A better system might be a non-conductive ejector or shallow trap door safety zone that removes the person/object from the path of a train until it has either stopped or passed by. I\'m not saying that a person should be unceremoniously catapulted back onto the platform if they have fallen onto the tracks but, I\'d rather suffer a few bruises than be struck by a train.
John Potter
It is with regret the latest: Mother 23 trying to retrieve her phone (from track). . from Walton-on-Thames, Surrey, was hit by an express train on Sunday at Wimbledon station. Im Sorry...