On-road and in-vehicle are not in competition

The integrity and accuracy of data that can be verified by weigh-in-motion technology has been improving for decades – and the range of WIM applications is increasing at a tremendous pace.

Chris Koniditsiotis, president of the International Society for Weigh-in-Motion (ISWIM) and CEO of 7205 Transport Certification Australia (TCA), began his career in 1985 as a pavements engineer. “When I joined this portfolio, the integrity, accuracy, and sampling frequency of mass information delivered at best an estimate, used in research and specific projects,” he explained to delegates at the ISWIM WIM Forum in Brisbane, Australia. “Routine or day-to-day use was limited to on-road systems and investments usually championed by individuals in road transport agencies and associated research and academic institutes. Back in 1985, we dreamt of the day when we would more routinely have available to us mass information with improved integrity and associated accuracy, and a frequency that provided insight and hence, allowed us to address directly the policy challenges.”

Integrity and accuracy

He asks whether the industry has now “arrived at and achieved our goal of integrity, accuracy and a sampling frequency of the collection of mass information to achieve our multiple uses? Has the journey that we have travelled over the past three decades reached its destination”? Koniditsiotis believes the answer is ‘yes’. “With respect to on-road WIM systems we have a myriad of commercially available technologies and commercially available acquisition models,” he points out. “We have widespread networks of high-speed WIM systems used for a myriad of different purposes - additionally, we also see specific routes, infrastructure or operations which have specific units. We have progressed from not only using high-speed WIM as an information-gathering tool and filter for compliance and enforcement but to be able to achieve direct enforcement. With respect to in-vehicle technologies we witness again a commercially viable industry, and the availability of national specifications which customers can use to make acquisition and now increasingly the adoption of this by not only transport operators, but also end users to achieve their private and public policy needs.”

Key challenges

While the integrity and accuracy in the collection of mass information is now commercially available, he sees a variety of challenges:

1.  A recognition that on-road and in-vehicle are not in competition – they both monitor mass but for different purposes and policy uses
2. The need to operate, maintain and ensure the correct calibration of WIM systems, be they on-road or in-vehicle 
3. A recognition that they are operationally very compatible and in many regards co-dependent
   

When he started out in the industry, Koniditsiotis continues, “our use of mass was by necessity, conservative”. This means that “today we need to rethink and re-evaluate our uses and take into account the improved quality of mass information that is available”. He added: “We need to factor the conservative design, management, and maintenance estimates - or at least as a minimum, be aware of them - as this will provide a whole new set of opportunities across numerous policy areas,” he added, giving a couple of examples.

Traditional practice

Firstly, both on-road and in-vehicle systems require calibration, to ensure that ‘the scale or sensor’ is weighing properly. “The traditional practice is to apply a temporal condition,” he said. “We calibrate every three months, or every six months, or annually. However, in practice, we all recognise that some WIM system sites tend to be better than others and some operating environments and their weighing systems tend to last longer than others. We have an opportunity through the co-dependency of these two technologies to improve the calibration process. In doing so - for one to inform the other - so that collectively both benefit from being aware of when ‘the scale or sensor’ is out of calibration and providing an evidence-based approach to ensuring it is maintained.”

Taking opportunities

His second point was that, while a “conservative nature” has been built into the design, management and maintenance of infrastructure, it is there for a legitimate reason. “It is there to cater for the things that we don’t know, it is there to cater for the occasions which exceed the expected,” he continued. “Today though, with this greater integrity and accuracy that mass information provides us, can we absorb that safety factor that has been put into place so that rather than estimating the worst case, we recognise and give credit to the best case. The opportunity presents itself for the use of both on-road and in-vehicle weighing systems to provide greater confidence to all stakeholders and provide for increased productivity but also not compromise the safety that is expected by all.”

He concluded that the two approaches - on-road and in-vehicle - can co-exist “and indeed complement each other”, and urged the industry to recognise “the opportunities that greater integrity, accuracy and measurement frequency provide us”.

The speed of change

Weigh-in-Motion (WIM) technology is increasing in sophistication at an extraordinary rate and – as the range of its applications also expands – this is posing fascinating questions about the ways in which we should be using the information that we can now extract.
Chris Koniditsiotis, president of the International Society for WIM, has seen a great deal of change over a distinguished career in the industry and suggests that the integrity and accuracy of the data at our fingertips now creates real opportunities.

“We have progressed from not only using high-speed WIM as an information-gathering tool and filter for compliance and enforcement but to be able to achieve direct enforcement,” he says.

Integral part

WIM technology is already an integral part of charging and enforcement activities, detecting overloading and calculating road user fees among other things. It is a key element, for example, in 4984 Kapsch TrafficCom’s recent €76.7 million deal to set up a nationwide tolling system in Bulgaria - which involves the installation of 100 WIM facilities, as well as tolling gantries, a data centre and back office – after the company created similar systems in Austria, Switzerland, Poland, the Czech Republic and Belarus. When it comes to the hardware, companies are keen to emphasise the range of what is achievable. 657 Kistler is highlighting its new WIM solution at 70 Intertraffic in Amsterdam, KiTraffic Plus. With the potential to be combined with camera systems, weight enforcement and toll-by-weight are among its applications, and the company says it can measure vehicle loads at different speeds “on a virtually infinite number of lanes”. Kistler says it is the world’s first WIM system based on subsurface quartz sensors. The Lineas Compact sensors – two to eight of them per lane - are installed 25mm below the road surface and covered with a grouting compound which, Kistler says, “ensures an extended sensor lifetime”.

New solution

7691 Cross Zlín says that its newly-launched OptiWIM sensor - shortlisted in the Infrastructure category of the Intertraffic Amsterdam Innovation Award 2018 - can measure a vehicle’s axle width directly and detect the use of double-wheel assemblies or the presence of underinflated tyres, even in dual-assembly, separately. The firm says that its new solution, which has spent two years in testing, even weighs accurately when trucks drive between lanes – such as when overtaking.