Intelligent spreading - winter maintenance with a twist
Published: 30 March, 2012
What was once a case of dumping sand on the road is now a high-tech business. Ann-Marie Knegt reports on the latest winter maintenance vehicle technology.
Andrew Bunce, Sales Director of Bunce Ashbury, distributor for Epoke spreaders, believes that the winter maintenance market is currently reacting to the risk of increased litigation against councils. One result has been a demand for data-logging systems on winter maintenance vehicles.
“All main operations which are carried out during a spreading run are recorded on a control box - e.g. time of run, the taken route, driving behaviour and the spread settings used,” explains Andrew.
“This information is both a useful management tool to check that operations have been carried out right as well as potential defence against litigation,” he reports.
“I have heard of cases like this one - the police have arrived at the scene of an accident where the road had been treated with the precautionary 10 grammes of salt per square metre. They notice the verges are covered with frost, but they cannot see the salt on the ground and therefore write in their report that the road is not treated - which is often not the case.
“This is not very helpful, and could mean the council might end up in court. The police need to be aware of the fact that a road can be adequately treated without the need to actually see a thick carpet of salt,” he comments. The example mentioned above is one of the reasons why Epoke have patents on the Epoke EpoSat system.
The Epoke EpoSat system.
This system enables spreaders to be automatically controlled from satellites via GPS positioning. When EpoSat is installed on the vehicle, the driver only needs to concentrate on his or her driving. The spreader will automatically correct and adjust the spread rate and spread widths according to the co-ordinates of the route.
According to Andrew the whole operation will be carried out more effectively than just relying on the driver and his codriver. It also means that more than one operation can be carried out at the time.
“There could be a point in the route when, for instance, the spread-rate, width and symmetry of spread have to be changed at exactly the same point. GPS enables this instantaneously. It also make sure that it will happen at exactly the same place every time the route is treated thus ensuring the route is â€˜correctly' treated,” he explains.
This inbuilt â€˜intelligence' as Andrew refers to it, knows its own speed and position and it anticipates changing functions. When these tasks are performed manually, it would be very hard to accomplish the same â€˜exact' results and it could mean that the road would not be treated, as it should in all places.
He gives the example of a gritter driving at a speed of 50 km an hour (just over 30m). In this time the vehicle will travel almost 14 metres in one second so any delay in adjusting the spread can have serious consequences to road safety.
“Furthermore, the system is easy to set up and the software used enables the management to edit the route easily without the need for driving the route again,” he continues. “We have also incorporated safeguards in case the driver has to deviate from the correct route.”
Lincolnshire County Council is the first authority in the UK to use EpoSat GPS and is currently performing trials up to late November.
Andrew adds: “We believe that Epoke EpoSat system will make a major contribution to improved safety and performance in winter maintenance practice.”
As mentioned before, Epoke is not the only company to react to a changing market. Spreader manufacturer Schmidt also identified a need for more accurate spreading within their circle of customers.
That is why the company developed a new range of control systems to provide high accuracy spreading. This range comprises models for different requirements, for example: three lane motorways, urban highways with cyclepaths, bus lanes, chicanes and speed control devices as well as street furniture and narrow country roads and lanes.
“We developed the CB system after customer research identified a need for a basic remote control system. Where sophistication is not a priority - for example, in smaller councils handling non-complex routes with few climate or geographical variations - the CB system enables the driver to carry out all major control functions from within the cab using an easy to operate control box,” Paul Diver, MD of Schmidt UK, tells LAPV.
The company also offers more advanced systems for councils, which stretch over more geographically-varied areas. “The more advanced CX system features a new in-cab control box and incorporates new levels of precision and control. It follows similar design principles to the control range currently in use with existing Schmidt spreaders, with easy to use â€˜click' buttons and a clear display,” Paul continues.
The sophisticated top-of-the-range CL system has a range of options, including ruggedised memory cards and GPS satellite communications for data logging and communications. “Furthermore, the system can be linked with Schmidt's â€˜Thermo logic' and â€˜Autologic' systems.”
Autologic allows routes, spread rates and dosages to be preset, enabling the driver to just concentrate on driving. The system handles the winter maintenance functions.
Both CX and CL use CAN BUS and CAN OPEN protocol. Another new development is the â€˜contact-less' salt sensor for monitoring salt delivery as an alternative to the metal loop sensor.
Where previously the Thermologic system was working along a set route treating the roads based on real temperatures, the new improved system enables drivers to input predicted temperatures, this new possibility is called the â€˜offset temperature' function.
Paul explains that if a driver has to treat a route at a time when the temperature is higher than it will be in an hour or so - for example at 19.00 the road temp is 1°C, but forecasters predict -5C° at 20.30 hours the operator can set the predicted temperature.
“Thermologic interrogates actual surface temperatures and uses this data automatically and instantly adjust dosages and spread rates. The offset function will now calculate the direct dosage for the entire route, including fluctuations for shading and different heights, based on predicted temperature.
“The operation never stops spreading; it just maximises effectiveness by doing accurately without waste, this has proved to deliver up to 15% savings on materials with improved performance,” Paul concludes.
Different calibration options
Andrew Lupton, MD of Econ Engineering, explains that Econ's own independent research has revealed that to cope with all the different types of salt that are currently marketed in the UK a spreader would need 65 different calibration settings.
Although this difference between the settings might be small, he recognises a need within his range of customers for a finer control of the systems.
“This means that we as a company have little choice but to offer these options. In conjunction with this, there is an everincreasing demand prospect of litigation for malpractice, within the provision of the service has lead for the control of the spreaders to be done via external means. In the last 6 months we have launched several external control systems,” Andrew explains.
Econ has developed an open architecture interface for GPS systems in their spreaders as well as the Smart Card System.
Andrew says:”The latter is driven by one of the main key performance indicators, namely the coverage of the entire network before the temperature reaches a freezing point. When plotted on a GPS map proof positive is given that the service was performed as stated within the contract requirements.”
Econ's smart card system comprises of sensors that are fitted throughout the spreading equipment. The data is transferred from the cab to a Windows based PC using a smart card. The system is designed to be simple to operate with an in-cab writer and an in-office reader based on one card and one route.
This is an easy way to keep track on fleet performance and your operations as well as a protection against litigation. Furthermore, the company offers SPARGO, a control system that features a twin-dial control for spread width and spread pattern. The spread width is now a standard function and is continuously visible on the LCD in-cab display. Other information is also accessible and can be controlled with the joystick that adjusts the discharge rate and when activated a snowplough.
Spargo enables the driver to fully control, via switches and buttons; the blast, pre-wet functions, snowplough, beacons and spreading functions.
“This format is driven by key research performed by the NSSRG society, which performed research on the effects of different road surfaces, the application of salt on different road surfaces and of those road surfaces to hold water and therefore freeze far more readily,” he says.
“Several local authorities have brought it to our attention that the use of porous asphalt has lead to problems with water remaining in the pores. This requires far greater dosages of salt to prevent the surface from freezing. Roads constructed from other materials such as SMA pose the same problems,” he reports. “Clearly it is not practical for a driver, whilst travelling at 28mph at night to be able to detect which surface is on the carriageway at any given point during the route. Therefore, external control of pre-setting the discharge rate against the road surface is a natural progression. We, as a company, expect most progression in this area in the next 12 months,” Lupton concludes.
Behaviour of road users
In conclusion, Andrew Bunce from Bunce Ashbury adds: “Regarding driving in winter conditions, the average UK driver could benefit from some education about the whole winter maintenance process and would also benefit from training in icy conditions.
“Very often the average driver sees the weather forecast on the evening news that there will be a frost the next morning, however, they very often still awaken at the same time as usual, go through their normal routine leaving their front door exactly the same time as usual, only to find the car is encrusted with ice. They then either spend 10 minutes de-icing the car which makes them 10 minutes late and so they drive that much faster on roads which perhaps unsafe, or perhaps worse still, they only clear small viewing hole through the ice and drive their car in a dangerous condition on possibly dangerous roads,” he says.
“I know that a number of Councils issue leaflets advising drivers about safe practices together with a map of their area showing which roads would be treated on a normal salting route.”
In response to the severe US environment of litigation the company IceAlert has developed temperature displays for road users that work as a standard reflective marker during the year, but as soon as the mercury level reaches 2°C the internal blue reflectors driven by a mechanical thermostatic action, progressively move in to view. The amount of blue visible in the window indicates the likely risk of ice, and the blue reflector will be in full display by -1°C, indicating a very strong possibility.
The device has several important benefits. It indicates the risk of ice at each specific location and can be placed in areas with known freezing tendencies or a history of ice related accidents. Under icy conditions the reflector is very apparent and the dramatic change creates a very high visual impact. Unlike other variable message signage it is in expensive and requires no power and no more maintenance than an inert roadside reflector.