Video analytics is the use of computer intelligence to perform repetitive surveillance tasks. Typical applications include monitoring a site for intruders (for example depots and track for cable thieves) or unusual behaviour at level crossings where pattern and direction of movement of people and vehicles should conform to prescribed norms. Writes Alex Renton Senior System Engineer, Vital Technology
To date, this technology has been underused in the rail sector. However, take-up should now increase with the introduction of a mobile rapid-deployment tower system consisting of CCTV cameras mounted to a hydraulic extendable mast, onboard analytics, integrated power supply and the ability to send email alerts straight to a smart device or Alarm Receiving Centre.
More than just motion detection
One must not confuse video analytics with cruder ‘motion detection’ systems. These generate alarms on movement but are unable to distinguish more complex target behaviour such as legitimate train traffic and therefore they can create nuisance alarms.
Vital Technology has exploited recent advances in intelligent scene analysis to develop Xtend. This offers rail infrastructure operators and TOCs a nine-metre high, 360° of rotation tower with four CCTV cameras operating from a ruggedised trailer unit. The trailer is manufactured in Lincolnshire by Vital’s collaborative partner, Morris Site Machinery. The SMC Eco-90
environmentally-friendly mobile unit is adapted from the industry leading, Network Rail approved SMC TL-90 mobile lighting tower.
Xtend has been purpose-built to be transportable across difficult terrain to remote locations of high value or vulnerability on railway routes. These can include storage depots and temporary work locations where plant and assets remain in situ overnight. The product can create a sterile zone or ‘virtual tripwire’ around significant targets containing copper cable and other valuable metal components during engineering works.
Any current observer of the UK rail network will have noted extensive cable-pulling projects and the running of new fibre and copper along the lines themselves. Plant and cable are being left trackside and great demands are being made of manned guarding resources. Route managers can now protect cable-pulling and troughing equipment, with the Xtend trailer units simply moving down the line as works progress.
Network operators will appreciate that Xtend can be used at rail-side locations prone to flooding where fixed mounting poles are impractical. Engineers and site safety managers should therefore consider using the unit at locations with varied topography where CCTV has never been contemplated before. At hazardous locations including earthworks, Controllers of Site Safety (COSS) now have a new means of supervising operations and implementing safety codes, with convenient playback of high- resolution footage for instructional purposes. Weighing 850kgs, Xtend can be taken to virtually any location accessible by a vehicle or it can be winched into cuttings.
Alarms are not limited to intrusion. Xtend differentiates between a range of target types and behaviours, performing analysis according to specifications that include filters on direction, presence and speed of movement.
Detecting no motion
The system can also generate an alarm if a target is stationary where it should not be (e.g. a vehicle stalled on a level crossing) or at crossings where pedestrians behave in an irresponsible manner.
Another scenario is ‘loitering’ where a target is taking too long to move through an area, e.g. a person contemplating suicide from a bridge. Here, the analytics generates an alarm on the situation, prompting human intelligence to assess the atypical movement pattern which can of course be for many reasons.
Statistics collated by the Rail Safety and Standards Board (RSSB) show that there were 265 suicides on the UK rail network in 2009, this being four percent of the national total. Video analytics is proving increasingly successful in alerting on suicidal behaviour. There are, of course, limitations to how artificial intelligence interprets human behaviour, but the inevitable false positives are a small price to pay in terms of the humanitarian cost, which may include driver trauma.
Xtend can be delivered to a location that has temporarily become hazardous or the target of anti-social behaviour (e.g. a railway station) in a matter of hours and the presence of the unit can act as an immediate deterrent. Facilities managers will be aware that the process of researching a CCTV installation, buying cameras, carrying out groundwork for poles/masts takes a minimum of six weeks. Network operators should also note that Xtend can prove invaluable when new station projects are at an intermediate stage or when stations are being refurbished.
As with rail suicides, Xtend can also protect the public by creating alarms in the (surprisingly common) scenario of misguided would-be cable thieves attacking live overhead line equipment (OLE), behaviour that is more common in the tram sector than on railway networks.
The Xtend system requires absolutely no local infrastructure for implementation; it is fully self- powered and will operate on its diesel generator for over 250 hours using the CCTV only. A battery option is available and if the site is near permanent infrastructure, Xtend can be mains-powered.
Incidentally, at an additional cost in terms of fuel consumption, engineers can use the trailer to power tools, lighting and welfare facilities.
A core feature of Xtend is that notifications of unusual and potentially threatening situations can be sent via email to a PC or any ‘smart’ device including mobile phones. This functionality can be combined with the more traditional method of review at Alarm Receiving Centres (ARCs). Video transmission can be a local-wired connection or via point-to-point wireless allowing links of over one kilometre. Xtend also exploits 3G and satellite transmission so it can be used almost in the middle of nowhere.
The extent of the views from the four cameras with the hydraulic mast extended to its full nine metres means that large premises and sites can be protected. Cameras can be high-definition and up to 36x zoom, while rail operators who need to secure extensive perimeters may opt for a combination of conventional (day/night) cameras with thermal imaging cameras which will detect heat signatures. The daylight cameras can also switch to mono after nightfall, improving image quality during the hours of low light, especially when combined with infrared illuminators.
Xtend relieves management of the obligation to ensure that hours of eventless video footage is monitored by security guards. The system only processes meaningful data i.e. unusual situations that may pose a security or safety threat. In this way, the product optimises use of computer bandwidth and storage space.
For rail clients who need to respond promptly at lineside hotspots in difficult locations or protect their assets at depots, yards, halts and stations, Xtend offers a flexible, real- time security solution 24/7.