MOTORWAY tunnels are fundamentally challenging to operate. Deep underground they are remote from control centres and their required 24 hour/7 days per week traffic operation means they can’t be physically managed as big commercial and industrial sites might be.
What this meansis that motorway tunnels demand the integration and operation of exceptionaland diverse control systems from video surveillance and associated analytics,to fire control, ventilation, lighting control Radio Re-broadcast, PA and arange of additional subsystems.
In the controlroom, operations staff must have fingertip control of this host of systems, as well as being able to see the state of all systems at a glance. Alongside this general overview of the tunnel, operators also need the ability to drill down into each system to extract real time footage, check alarm states or controlmessage signs and jet fans etc.
While the day today operations of tunnels are challenging it’s impossible to talk about RiverCity Motorway Group’s 6.8km Clem7 Tunnel without acknowledging the profound challenges of the installation itself. This was a vast infrastructure projectthat took 3.5 years to build and cost $A1.9 billion dollars.
While the surveillance element is a small portion of the whole control system, the nature of the CCTV installation here is indivisible from the overall build. The Clem7Tunnel itself shaped the nature of the installation process in a fundamental way.
Also tough from the point of view of the narrator, is peeling away layers of overall control system integration to expose the nature of the video surveillance system. The challenge is that the overall solution represents a profound integration of a type most CCTV applications never approach.
The Clem7 Tunnel
One of Queensland’s largest ever infrastructure projects, the Clem7 Tunnel is owned by RiverCity Motorway Group and managed by Brisbane Motorway Services. Design and construction of the project was handled by Leighton Contractors and the Baulderstone Bilfinger Berger Joint Venture.
Electrical and Mechanical systems, including CCTV, were designed and installed by UGL Infrastructure, which has also completed many other tunnels, including LaneCove Tunnel, Sydney Harbour Tunnel, the M5 Tunnel and Melbourne’s City LinkTunnel. The bulk of the surveillance gear, including 375 cameras, a Pelco matrix switcher and DVRs was supplied by Pacific Communications.
According to Brisbane Motorway Services Clem7 operations manager, Brendan Gough, the tunnel was conceived as a North/South bypass of the Brisbane CBD as part of Brisbane City Council’s TransApex Plan which incorporates the CLEM 7, the Northern LinkTunnel and another tunnel to the south of the city.
“The project is 6.8km long overall with 4.6km long underground and is a dual tube construction with a pair of 3.5m lanes running each way,” Gough explains.
“The contract stipulated that to operate the tunnel we had to able to detect and monitor all incidents inside it,” he says. “The tunnel has to monitored in real time, 24-7.
“There are 375 cameras throughout the Clem7 project including cameras in the tunnel with continuous coverage overlaps underground so there are no blind spots.
“CCTV is used onset tours to do sweeps of the area ensuring rapid response to breakdowns and there’s an integrated automatic video incident detection system (AVID) video analytics solution that is worth its weight in gold,” says Gough.
“As well as 2 operators in the control room, there are 2 response crews on the road and during peak hours they are located nearby so they can quickly respond to incidents in the tunnel.”
While the system has an obvious safety role, there are also security functions.
“Operationally the surveillance system offers both safety and security,” Gough explains.“Firstly, you’ve got safety for motorists, you’ve got traffic monitoring for congestion – the AVIDs will detect slow traffic, stopped traffic, smoke andother traffic incidents.
“And security is an issue, too. Clem7 Tunnel is a key piece in the road system in Brisbane so weneed to ensure nothing untoward happens – there are electrical supplysubstations, air management systems and water treatment plants that form partof the overall project. We do keep an eye out to ensure security in and around the Clem7 project.”
This is a hybrid CCTV solution with analogue cameras running to local cabinets in the tunnel where they are converted using multiplexers. Signals then travel to the control centre on fibre optic cable. Once back in the Tollroad Control Centre, signals are de-multiplexed and the feeds then handed over to a Pelco CM9760 Master Distribution Amplifier, then to a Pelco 9760 switcher and then the automatic video incident equipment, PDR-Platinum-D1 Pacom DVRs and monitors in the control room.
The choice of a hybrid system was dictated by a range of considerations including the demand for 100 per cent uptime and zero latency. The system also represents what was undeniably the most reliable and proven technology when designed back in 2006/2007 and the images provided by a mixture of Pelco and Ikegami cameras offer excellent quality in the challenging underground environment.
According to Pacific Communications’ Queensland state manager, Hardi Kurnadi, all the video surveillance hardware components were supplied by Pacific Communications and they include a Pelco Matrix Switcher CM9760 (384 video inputs x 64 video outputs) along with 3 Pelco Keyboard CM9760-KBD units.
“The cameras include 57 Pelco Spectra 4 PTZs, 286 ICD-809 Ikegami fixed cameras, 28 PelcoEsprit IOP camera units, 3 x DVTEL 8 channel encoders and 30 Pacom PAC-20RTH monitors. There are also 2 Pacom PDR-Platinum-D1 16-channel recorders.
“All the Fixed cameras inside the tunnel are Ikegami colour cameras. There are dome cameras in the tunnel which are made by Pelco and include a 35x zoom.
As Kunardi explains, the overall system is analogue with camera images arriving on fibre then passing through a Pelco 9760 switcher where signals are split, some to AVIDs and others going to DVRs.
“We take fibre in, it goes to coax then to a Master Distributor Amplifier and then to arelevant outlet. In terms of system performance, image quality is D1 resolution with a frame rate of 25 images per second.”
One of the key drivers of the choice of hardware for the CCTV system is the fact video image processing for analytics depends on the quality of the image received. Fixed cameras are preferred for use of video detection, according to the video incident supplier, though the company also makes VIP boards that support PTZ cameras.
There are also specific requirements in terms of ideal camera performance when using video analytics, including CCIR/EIA 1Vpp (+/- 20%), a CCD sensor, slow iris regulation, no AGC, no frame accumulation, an infrared filter, no blooming and good contrast. The installation also needed to take into account a mounting height suitable for video analytics using the AVID solution.
The integrator ofthe Clem7 project was UGL Infrastructure which designs and constructs mechanical and electrical systems for large infrastructure projects in diverse areas such as water treatment, power utilities and tunnel projects.
In the CLEM 7 Tunnel UGL Infrastructure performed nearly all of the systems design, including CCTV, while the civil contractor LLBJV designed and built the tunnel using Tunnel Boring Machines (TBMs).
As soon as LLBJV completed the tunnel lining, UGL Infrastructure commenced installation activities including cable trays, lights, fans, electronic signage (tunnel message signs, variable message signs and speed limit signs) and the video surveillance cameras.
As part of the process of developing the video surveillance solution, UGL Infrastructure initiated a competitive tendering process to suppliers with experience in large CCTV surveillance systems for which Pacific Communications were the winning tenderer. UGL Infrastructure produced design reports that demonstrated the selected system met the requirements. This design was submitted to all stakeholders for review and approval.
Operationally,the CCTV system at Clem7 is designed with a high availability (99.995%) via overlapping coverage and full redundancy of key components. Inside the tunnel there is a fixed camera on the roof every 58 metres while there is a PTZ camera at 116 metre intervals. The 116m spacing corresponds to the distance between Emergency Egress passages in the tunnel.
The PTZs at each passage can look 120m either way that allows operators to pan, tilt and zoom in order to get a good look at situations in the tunnel. The tunnel itself is viewed as a higher risk place to break down so the coverage there is denser.But CCTV coverage is not limited to the tunnel itself. At the project boundaries there are also AVID enabled cameras and PTZ cameras.
Meanwhile, in the control room nominated vital cameras viewing traffic hot spots are displayed on a video wall as part of a tour so operators viewing them have the best chance of seeing an incident in real time.
UGL Infrastructure specifically decided to implement analogue based cameras and ananalogue switcher at Clem7 in order to avoid latency when trying to switch IP packets of data quickly.
On a system with nearly 400 cameras such reservations are understandable – particularly given the system was designed in 2006/2007. Also relevant was the fact that at the time the system was designed the video incident supplier did not have an IP-based solution in its range.
Also important for UGL Infrastructure was the fact the company’s engineers had worked with the Pelco and Ikegami cameras before and knew how they operated and what their strengths were. The advantage here was that it meant UGL Infrastructure could install only those products and designs it was completely confident of.
In applications like this where uptime is paramount, integrators resist jumping to new camera technology only to find there’s a problem later and have to go in and swap outall the cameras and/or lenses in an operational tunnel. With tunnel CCTV systems, installations have to work from day one.
Given the size of the Clem7 project the backbone of the video surveillance solution is a vital component of the system and given the distances involved it’s no surprise UGL went with a fibre optic solution. In this installation a fibre backbone is run from the control centre all the way down to the motorway. The complete fibreoptic backbone is not dedicated to the CCTV system. The backbone is also used for other systems designed, constructed and commissioned in house by UGL Infrastructure.
From an installation point of view, there are cable tunnels running through each tube of the tunnel and each carries the data backbone for all its electrical systems. These runs have links up into the cross passages which have electrical rooms located within them. With the CCTV system, modems convert coax signals from the analogue cameras to fibre optic signals. The short coaxial cable runsout to cameras in the tunnel are not more than about 60m.
The system is based upon redundancy and importantly for reliability, there’s limited CCTV gear in the tunnel, primarily from an access point of view as it is not easy to get to a location if something fails. Maintenance involves closing lanes and it can be a long process to get things done.
Tunnel equipment must be simple and very robust so as to handle temperature variations,vibration, dust and dirt. This means that at Clem7 it’s just fibre and multiplexers in the tunnel with all the head end equipment as well as video analysis units and video storage handled at the Tollroad Control Centre.
It’s not just monitoring of the roadway that’s important at Clem7. There are also emergency doors and emergency cabinets positioned along the tunnel – hundreds of them –and all these alarm inputs monitored in real time from the Tollroad Control Centre via an integrated Operational Management & Control System designed in house by UGL Infrastructure.
All the doors in the Clem7 project have a mechanical switch that’s linked into the PLC systemand monitored in the control centre. If someone opens a cross passage door inthe tunnel and trips a door switch, software is programmed so not only is an alarm signal sent to operators, designated cameras also move to preset positions viewing doors so operators can see what’s going on.
There are also cameras inside the cross passages and those cameras will also come up on the operator’s screens if an emergency door in the tunnel is accessed. The operators can then use the PA system to communicate with anyone in the passageor road tunnel.
Along with exit doors, there are also Emergency Equipment Cabinets located every 60 metres along the tunnel and each has a door switch inside. If a cabinet inside or outside the tunnel opens a camera will immediately swing around to a preset position that allows viewing of the door/cabinet. Clearly, in terms of integration, this is no ordinary solution and UGL Infrastructure is no ordinary integrator.
UGL Infrastructure specialises in taking all the signal inputs from multiple systems and combining them with system programming so that if a particular event happens, then a particular action is taken. There’s a code to handle this and door switches generate one sort of event.
Similarly if someone picks up a telephone, they will be connected to the Tollroad Control Centre and visually monitored by the nearest camera. In normal operation no one is opening a door or picking up a phone so every time something like that happens then operators know something untoward has occurred. This makes operators’ lives far easier.
Not surprisingly there were significant challenges with the installation but it was not technical issues relating to CCTV equipment that stretched the UGL Infrastructure installation team. The problems with these large projects relate to time pressures. Because it’s a toll road, management and investors want to start collecting tolls as early as possible and in this case the Clem7 Tunnel opened 7 months ahead of schedule.
For installers, the sequence of events is to put the trays up, put the cables up, install the devices and then get power on. By the time a camera is finally turned on, it is reasonably late in the overall process. Essentially the cameras were installed and plugged in as part of the final commissioning process.
Also an issue was the fact the AVID system needed to be fettled by hand – no easy task on a building site like this one. Techs spent 3-4 months driving cars up and downthe tunnel, stopping, slowing down and throwing boxes out the back in order to program the AVID filters.
Challenging too, because of the intense safety focus of the tunnel, techs also had to prove that at every point the CCTV and associated door alarm system worked, every alarm functioned properly and reported to the control room before opening day.
All these tests have to be sequenced accordingly because of the significant distances and associated travelling time. If a technician has to go back and adjust one parameter or change a single bracket it’s a major operation. All this vital work takes place while other contractors undertake their own last minute works including painting of ceilings and installation of wall panels.
The logistics of having many people working in such a small space are quite challenging. Just getting a technician 2 or 3 kilometres down a tunnel during the general commissioning process is an effort. There are speed limits (eg – 10km/h) that means it may take half an hour to get to the work face and if a technician finds they’ve forgotten something that’s an hour round trip to retrieve it.
Environmental issues faced by UGL Infrastructure for camera installation included image resolution due to lighting levels and vibration from the tunnel ventilation system generated airflow. Initially UGL installed 24x zoom PTZ cameras in the tunnel; due, however, to the mentioned issues; these were replaced 35x units.
The business end
Given the only elements of the system in the field are cameras fibre converters and multiplexers, the business end of the Clem7 surveillance installation is thecomputer room and main control room in the Bowen Hills Control Centre.
The computer room is large and well laid out and the CCTV installation is very well done. The Pelco 9760 particularly impresses. You don’t expect to see new analogue matrix switchers these days thanks to the penetration of IP solutions but this one is a real peach.
The installationwas performed by UGL Infrastructure and overseen by Pacific Communications. UGL Infrastructure insisted it be cabled in miniature RG-179. The results are veryimpressive – it’s definitely among the sweetest matrix cabling looms around. This is a redundant switcher with a hot swap unit and 2 processors.
Along with the matrix switch, other elements of the system located in the computer room include modems and fibre racks with single multiplexers that decode surface cameras and 4 channel multiplexers that decode signals from the tunnel.
As we walk through the computer room, It’s easy to see the system elements in their 19-inch racks. There are the 2 cabinets for fibre one from the north-bound tube and one from the south-bound. They are redundant for each other based on the UGL Infrastructure design. This same rack also contains the modems for which Pacific Communications oversaw the wiring.
The rack next door holds the Pacom PDR-Platinum-01 DVRs which handle recording. There are 16 channels on each of these recorders giving the ability to record 32 cameras simultaneously. The cameras designated for recording are in areas identified by the operator’s, other cameras are switched to record on specific events like door openings.
Alongside these DVRs are the AVID units which handle analytics. The AVID detection unitsconsist of a number of VIP (Video Image Processor) boards and a communication board integrated into a standard 19-inch rack.
Out of the back of this rack comes an MPEG video stream that can be viewed live in the event ofan incident with a clip sent to a video server. This functionality is repeated for every video incident camera in the tunnel and the surface. Everything is redundant and there are also redundant ring switchers that go all the way around the tunnel. The entire system inside and outside is designed to be extremely robust.
The control room
Also vital to the business end of the system is the control room, it is a quality facility with multiple workstations supporting the myriad of systems that comprise the overall control solution at Clem7. Dominating the room is the video wall at thecentre of which is a very large computer screen. Gough explains that thiscentral display is a large rear projection screen capable of displaying the status of the Clem7’s plant, communications, power and traffic systems via fivedifferent schematics, all of which are part of the integrated system design andsupplied by UGL Infrastructure.
The Traffic Control Screen shows a live representation of the state of all devices in the project including current speed limits, current message boards, hazard warnings, lane closures and more. This screen allows more efficient management by providing a complete picture of the tunnel’s state in a glance.
Handling videosurveillance are 24 Pacom monitors – with 12 on either side of the video wall.These monitors display continual tours of key cameras, with these supported bya further 8 monitors onto which incident detections are highlighted.
“The resolution is good – we use good quality monitors, modems, coax, we are very happy with the cameras we have installed,” says Brendan Gough. “There are multiple systems in the control room, the video system, the fire system, the Operational Management System, a log system.
“Operators can see the big picture on the plan and then drill down to a particular device or view a scene from their workstations – it’s a very complete solution,” he says.
Video analytics is integral to control room operation. It goes without saying that monitoring 375 cameras with 2 operators would be challenging. Use of an AVID solution assists operators by drawing their attention to a range of pre-programmed conditions that indicate incidents inside the Clem7.
Management of the surveillance system is handled by intelligent video detection management software that collects traffic data, events, alarms and video images generated by the video detectors and allows complete management and control. It provides a user-friendly interface that allows real-time monitoring of events and alarms. All event info is automatically documented and visualised in a straightforward way, allowing managing each traffic situation efficiently.
The client of this interface is a web-based application. This means users only need a web-browser installed on their PC that is connected to the network of the video detection system to access the traffic management system. This web-based zero-install GUI provides more flexibility and better manageability for all users because there is no requirement to install client code or software on thePC.
As it is used to store and collect data, events and video, operators can immediately retrieve these recorded video sequences comprehending pre- and post-incident images.This direct visual information is not only extremely valuable for the operator to take all necessary actions in case of an incident but also for traffic analysis and evaluation afterwards.
To ensure event alerting, it allows maximum flexibility by the implementation of advanced filters which are a set of inhibitions that can be launched for a group of cameras. Each inhibition is characterised by events that must be filtered on one or more zones.
In terms of the function of the AVID system each camera has a dedicated piece of VIP hardware that’s doing the analysing. The system compares an incoming video stream with a default background in real time and if an anomaly is detected it will send an alarm and a video clip to control software to allow operators to see what happened. It’s complicated and expensive but it’s clearly worth the investment.
The way it works is that specific video feeds also go into the video analytics solution which converts the captured image stream to digital then undertakes analytics looking for changes in pixels to determine if there have been changes in a scene.
When a car goesby the system is looking for the presence of a car and then the rate of changeis depicted so it can estimate its speed and if suddenly you go from 80km/hr from 20 km/hr there’s an alarm that goes to the operator indicating a slow vehicle.
If a car stops there’ll be an alarm for a stopped vehicle, if a pedestrian gets out of the caror walks in the tunnel the system will detect them. The AVID solution will alsopick up fallen objects like a box and it will detect smoke. While the AVID system is not infallible, it’s generally thought to be about 95-98 per cent accurate which means it makes a major contribution to the efficiency of the control room and safety of the public using the tunnel
With an AVID solution it’s obviously a compromise between setting up the system to be so sensitive it detects a reflection from a light off a puddle or setting thresholds so high that no objects are detected at all. During installation the UGL Infrastructure team determined the settings that worked best in the Clem7 Tunnel. Post opening the UGL Infrastructure team worked to tune out the nuisance alarms by making adjustments to parameters in the software.
One of the benefits of the AVIDs is they are constantly recording so if there’s anincident, the AVIDs will save 60 seconds back in time which is advantageous as it shows lead ups to incidents in real time. A big discussion point on the Clem7 project was whether every camera should be recorded all the time. Thanks to the AVID system there’s no need to record every camera in this installation. Cameras that are triggered by an event get recorded. What happens is that when an event occurs the cameras get switched and an event gets recorded by the DVRs.
In the video incident system, image streams go into a card which is effectively a PC, onepart is storing that to a hard drive and the other part is looking at the image in real time. The recording on the Pacific Communications side is a DVR.
UGL Infrastructure took the decision that locating video footage of an incident needs to be performed with relative ease. The beauty of the AVID system is that it can catalogue video in an efficient manner. If therefore you are looking for a stopped vehicle at 8.36 am, you will be able to find it.
It’s fair to say that increasingly, recording every camera is an old-fashioned way of handling CCTV. You will never find what you are looking for in the real time recording of 375 cameras unless there’s some form of analysis and cataloguing of events.
“There could be some criticism that operators come to rely on the automated detection capabilities of the system to tell them something has happened as opposed to being proactive and constantly watching but this works extremely well,” saysGough.
“In other tunnels operators have to sit and stare at images from hundreds of cameras all day and there are meal breaks and toilet breaks and phone answering and there might belong periods of time no one looks at a particular camera and that’s where the door switches and alarms and the automation comes in.
“They give the system the smarts to inform the operators that something could be wrong.There’s a lot of redundancy in the system and to date we have had exceptional performance with our operators’ detection times vs traditional monitoring techniques.
According to Gough, cameras can pick up if a pedestrian or a cyclist has entered the tunnel. Both are prohibited.
“The AVIDSare programmed to recognise what a normal traffic carriageway should represent,” Gough says.
“In the event that the camera detects something it does not recognise as normal it will alert the control room operators to incidents including stationary vehicles,slow-moving vehicles, pedestrians, cyclists, debris and smoke.”
All in all, the installation at Clem7 is a remarkable achievement that represents a deep integration of hybrid technologies. There’s use of web based monitoring and digital storage with robust analogue cameras that run cool and have strong performance in low light.
Then there’s the AVID video analytics solutionand its associated impact on system monitoring and recording. The integration of analytics defines the Clem7 project as something special. It’s among the first major projects in Australia to exploit the power of video analytics in real time and from an operational perspective this type of application represents the future of video surveillance.