Keeping Track of Traffic
Gathering data is an essential part of road safety schemes and managing traffic flow. Chris Lo talks to a prominent traffic monitoring manufacturer about the best ways to keep a sharp eye on the road.
Congested roads and mile-long tailbacks have become a familiar feature of the industrialised world, from the misery of the daily commute to more exceptional delays such as Beijing's record-breaking 60-mile traffic jam in August this year. As infrastructure demand begins to outstrip capacity, authorities are forced to gather data and manage traffic flow to prevent the consistent build-up of vehicles on the same heavy-usage routes.
Traffic monitoring also plays an important role in road safety, giving police the tools to identify areas where speeding is a particular problem, as well as the ability to catch offenders in the act. But what are the most advanced modern systems used to collect and manage this data?
Induction loop-based detection systems can register every vehicle passing over a point in the road, smart cameras can track cars and photograph registration plates, and sophisticated software packages sort raw data into actionable information. We talk to Bernard Greene, managing director of CA Traffic, a UK-based manufacturer of traffic-monitoring systems and software, to find out how the right system can help authorities make sense of chaotic road networks.
Chris Lo: What applications are your traffic monitoring systems used for?
Bernard Greene: We've been in this industry for about 15 years; local authorities have been collecting data for much longer than that, and the data is collected to analyse trends. Traffic engineers can see the increase or decrease in traffic and apply some logic to that for the future. They might say: "At that volume of traffic increasing at 5% a year, we're going to need to resurface the road." It's an aid for the traffic engineer to start assessing the impact of increasing traffic. If they have undertaken some roadworks - built a roundabout or bypass, for example - they can use selected traffic counts to find out whether or not the new feature is having the expected effect.
CL: There must also be a road safety aspect to it.
BG:Certainly. Many speed cameras are supplemented by some form of count and classification or speed measuring. Two safety camera partnerships have bought a lot of our equipment but are returning data over GSM networks, and they're monitoring speeds on a weekly basis. So they will know that the speeds at this particular bypass have gone up to a point where they want to put a camera out.
By monitoring speed trends, it helps them to schedule the deployment of speed enforcement cameras, or even putting a police car out.
CL: What do clients expect from traffic monitoring systems?
BG:Continuity of data. They want reliable, continuous counting and classifying. They are more interested in the data than the technology we use to collect it, I think. So we have an approach that looks towards putting telemetry at monitoring sites so we can provide easy data collection and make the client's job simpler. We've got a software product called VDA-Pro that manages the data, scheduling the system to call individual sites, retrieving the data and adding it to the database automatically. We're trying to facilitate exactly what the client needs, which is access to good, accurate data. They don't really care about GSM modems, GPRS modems or inductive loop technology. They want to know how many cars, what sort of car and what time of day. What we're trying to do is make it easier for the customer to sit at his computer, hit a button and see what happened yesterday.
CL:What are the current technological challenges for traffic systems?
BG:We're trying to get the unit to do things at the same time that it registers the information coming in. So you're trying to work out another way of creating the inductive loop technology, you're trying to work out a way of putting some technology in the device that says "under these circumstances, my client wanted to know that traffic has slowed down to 5mph" or "this piece of information requires me to switch on a variable message sign". You can put more of those control functions in the unit, rather than have data go to a central processor and then be worked out. We can now get the unit to take action based on immediate local incidents.
CL:Is the use of solar technology an emerging trend?
BG:In terms of a green power solution, I don't think the power consumption of these sites is particularly high anyway. I think what the solar and battery back-up solution does is allows us to put sites in remote places. It's much more flexible, so if the client wants to monitor traffic at a particular point, he is not restricted by having to put a mains supply in there.
CL:What benefits can software packages have once the data has been collected?
BG:Our data management suite is called VDA-Pro, and we have a VDA Net, which allows access over the internet. We also have a new product called Catalyst, which is a new instation for the Black CAT [CA Traffic's monitoring platform].
It puts more flexibility in the hands of the client. The client is interested in the data; as long as the data is in the format that he wants and he can access it easily, he's a happy guy.
What we're trying to do with VDA-Pro is to manage the whole system for the customer - VDA-Pro will dial up all the sites, it will retrieve the data. If it doesn't retrieve the data on the first call, it tries again. The data is never lost; it's always in the machine, so if he goes back two days later, the machine will still have the data and know that he hasn't collected it yet. So we have a robust way of collecting the data from the outstations. VDA-Pro will automatically put that data in the correct tables for that location and the user interface allows the client to very easily collect the data from the locations that he needs to review.
CL:ANPR (automatic number plate recognition) cameras require a great deal of precision - can you talk about your Evo8 camera?
BG:The biggest benefit is that we've entered the market later than a lot of people who have gone through a lot of pain. So we've been able to use the experience of our designers from their previous roles to understand the complications of the technology and the discipline you need in terms of camera performance - there are issues with number plate reading for low sun, concrete roads, all sorts of things. We've gained from the experience of others in developing the Evo8.
We started the Evo8 with a clean sheet of paper two and a half years ago, and we now have a camera whose performance is acceptable to the UK police, and they are very demanding in terms of accuracy. It requires a colour overview image, it sends the data over 3G… So we've been able to engineer a product from scratch, knowing the current demands of the marketplace. We are trying to put some applications within it that are discrete to us, which will remain there for a while. But the application for journey time system is just an infrared camera reading number plates. The police require higher accuracy, combined with the overview image. So managing that data within a single camera, where absolutely everything happens internally, is quite difficult, but we've been able to achieve that with the Evo8. Everything is integral to the camera. It's a very smart CCTV camera with a lot of smart application software within it, to control the camera, to read the number plate and to dispatch it to the client.
CL:What do you think will be the next step for new generations of smart cameras and traffic monitoring?
BG:Cameras will become smaller. Our camera does dual-lane monitoring now, but I suspect someone will want systems to cover three lanes. So it's pushing the technology to deliver more data for less money and in a smaller package. In terms of the traffic data collection and ANPR cameras, it's combining the two things. One of our competitors on the count-classify side already has a product that can trigger in the event of an overweight vehicle.
Now that's a sensible application of combining the two technologies.
In our case, we've actually got ownership of the two technologies. So we can create an application whereby the Black CAT will measure weight-in-motion, triggering the camera to retrieve the image of an overweight vehicle and send it off to a waiting police car. It could also apply to something like lane discipline, where articulated vehicles are not allowed in a particular lane. If there was a particular situation where that was becoming evident, you could use the Black CAT to determine that there's an articulated lorry in a lane where it shouldn't be, and you could use the camera to take that image and send it to a police car. It's combining the two technologies to get more out of a system.
CL:Given recent stories about councils cutting speed cameras and a general reduction in budgets, do you think this is a concerning time for traffic data collection and road safety?
BG:I think it must be, because people should be using this technology to monitor speed and find out what's actually happening on the road. In terms of traffic data collection, it's not life and death normally, but the speed enforcement issue is one I suspect would make life more dangerous on the road. Anybody who thinks they can speed down a road and not get caught would just do it. So the answer is yes.