The Quartix InfoPlus option includes a comprehensive range of reports and displays, helping you work with your mobile workforce to improve their driving, reducing their risk of accident and cutting fuel costs at the same time. The reports available range from the daily driver briefing to the league table of driving scores which calculates total fleet performance during any period of time. The driver briefing shows speeds and utilisation for the day, together with the corresponding acceleration and braking profiles for the same periods. Links are provided from the graphs to the actual map location of any speeding, braking or acceleration incidents. The driver is given an overall score for the day based on the factors shown in the next section.
The Quartix system monitors the speed of the vehicle every second, and the acceleration and braking indexes are calculated from the number of times per hour that the speed changes by more than a given amount between one second and the next. These are then weighted according to how severe they are, and averaged over a driving hour to calculate the Acceleration Index and the Braking Index.
This speedometer shows the 10 levels of acceleration and braking, and each level has a weighting based on its severity. As such, speed reaching 6 mph in a second is a level 3 acceleration. Speed which goes down by 9 mph equates to level 3 braking, and so on.
The weighting of acceleration and braking events is shown in the table opposite.
The acceleration index is the sum of all the acceleration incidents, each multiplied by their severity and finally divided by the driving time in hours. The braking index is worked out in a similar way, except that the levels of speed change are slightly different, as are the severity weightings.
Example. If a vehicle is driven for 2 hours, and during that time there are 20 level 1 accelerations (severity 0.2) and 15 level 2 accelerations (severity 0.5) then the acceleration index is (20x0.2+15x0.5)/2 =5.75 This is a relatively low index, showing modest acceleration.
The Driving Style Score is the overall score out of 100 for a given period, typically a day, a week or a month. The system will add up all the weighted acceleration and braking events with their severities, calculate the total driving time and work out the Acceleration and Braking Indexes.
This graph shows an analysis of 830,000 journeys, giving scores for 64,000 'driver days'.
As described above, the calculation of the acceleration and braking indexes and hence the driving style score, are based on a 'per hour' calculation. Calculating the average per hour means that no drivers are penalised for driving more or less than any other driver.
The system calculates the Daily Driving Style Score for each day, based on the amount of driving for that day or shift (excluding any parts of trips before the start or after the end of the day/shift). We apply colours to the Daily Driving Style scores as shown on the plot opposite. If the score is >80 it is green - this represents the best 30% of drivers. If the score is between 50 and 80 it is shown as amber, and this represents the middle 50% of daily scores. 50 or below is red, and that's the worst 20%.
Driving style scores can be compared across groups of vehicles, or even the whole fleet. Driver ranking can be carried out on acceleration or braking indexes as well as the overall score, and can also be measured over any selected period.
Once the league table is compiled in the desired order and format, it can be exported to a csv file for further analysis in software such as Microsoft Excel.
The league table can also be displayed in graphical format, as shown.
Many of our customers have reported significant savings in fuel costs: an improvement in average driving style score from 50 to 80 could result in savings of between 8 and 14%. The two graphs shown highlight the typical difference to be achieved in the daily driver briefing.