Snow clearing machinery under FMC650 control

The FMC650 belongs to the professional range. It has its own GNSS module with high positioning accuracy, so the machine's track lands on the map street by street. The dispatcher sees in real time where each grader and gritter is, and after the shift receives the route overlaid on the plan of the roads being serviced. Missed sections and repeat passes are visible straight away, rather than after complaints from residents.

The second block of data is materials. The gritter controller is connected to the tracker through the RS232 port. The FMC650 takes from it the quantity of material spread and the spreading width and sends that to the server together with the coordinates. The result is a report: on such a street, such a machine spread so much salt. That is the basis for the report to the city and for finding waste, when de-icer is spread where the surface is already clear or while the machine is standing still.

The third block is people. Winter shifts are often longer than usual, and overrunning is easy. The FMC650 can read the data of a VDO digital tachograph remotely: who is at the wheel (the driver card number), what mode they are in, how long they have been driving without a break. One of the parameters is called exactly that — remaining driving time in the current shift, in minutes. The dispatcher sees that the driver has to stop in 20 minutes and plans a relief in advance, while the accounts department gets an honest basis for paying overtime.

The fourth block is technical condition. Through the FMS interface the tracker reads Tell Tale Status, that is, the same indicators that light up on the driver's dashboard: oil pressure, temperature, system faults. A signal about a problem reaches the dispatcher before the machine stops, and it can be taken off its route ahead of the breakdown rather than recovered out of a snowdrift.

In the monitoring system all these data come together in a single vehicle card. Where it is, what it has done during the shift, how much material has gone, who is at the wheel and how much time they have left, whether any warning indicators are on. For the head of the service that is a daily report; for the dispatcher it is a working screen for the whole night.

An example from a typical night. Snow starts falling at two o'clock, and the dispatcher sends six machines out on their assigned sections. By four in the morning he can see on the map that one section by the hospital is still grey: the machine that should have covered it is standing at the depot with an engine temperature indicator lit. The neighbouring gritter has already finished its route and is given an extra job. In the morning the report shows that every street was covered, and how many tonnes of material went onto each.

Drove past or treated. The track only shows that the machine drove past. A section counts as treated when the gritter controller reports at the same moment that it was working — or, on machines with older equipment, when a sensor shows the gritter switched on or the blade position. Otherwise a lorry that drove down a street empty looks the same in the report as one that gritted it.

Where the figures come from. The volume and the spreading width are the controller's readings, passed over RS232, not a weighing. How accurate they are depends on the calibration of the controller itself, so before the season it is checked against a known volume of material.

What the customer gets. A report for each section: when it was covered, by which machine, whether the gritter was working, how much material went and at what width. Missed sections come as a separate list, so that they can be dealt with the same night.

There is one limitation, but it matters: the tracker only gets the volume and the spreading width from a controller able to supply them over RS232. With an old mechanical gritter with no electronics you will have to settle for the fact of operation from a switch-on sensor.