Economic driving assistance
Poor driving style can increase fuel consumption considerably, by up to 15-25%. In particular, heavy acceleration and braking consumes additional fuel unnecessarily, while also making conditions unpleasant for passengers, increasing risk of accident, and increasing wear and tear on the vehicle. Transit operators encourage safer and fuel-efficient driving, and seek to detect poor driving practice.
There is relatively little that ITS systems can do to directly enforce fuel-efficient driving. Other than electronic “fly by wire” acceleration and speed governors, the full flexibility of the vehicle needs to be made available to the driver. Especially in urban transit operations, the performance is almost entirely up to the driver’s skill, awareness and attitude.
Fuel consumption rate indicators are fairly standard on both commercial vehicles and automobiles, giving drivers feedback to assist them optimise their driving style.
ITS-supported assistance to economic driving is mostly downstream. It assists the Transit Operator or Transit Authority to detect, analyse and follow-up with drivers who exhibit poor driving practice.
The following are the main methods used:
- Tracking and comparative analysis of fuel consumption by individual drivers, using both fuel records and the CAD/AVM operations data.
- Analysis of the GPS data from the CAD/AVM system to detect excessive point speeds or unusually short sectional journey times (which indicate speeding)
- Use of in-vehicle sensors to detect excessive g-forces, and excessive pitch and roll, which indicate sharp acceleration/braking and sharp cornering
- In vehicle sensor to detect excessive fuel consumption for the given set of driver inputs
- Analysis of materials from external forward-facing CCTV to view the actual driving style, and from vehicle-interior CCTV to detect passengers reacting to sharp driving and jolts
Technologies, data and resources
Economic driving assistance mostly harnesses the systems installed for other primary purposes. These include:
- the CAD/AVM system, operational records, and the GPS data
- in-vehicle sensors
- safety systems, including collision warning and avoidance systems
Specific technologies which are added to these platforms for economic driving support include:
- downstream tracking and comparative analysis software
- gyroscopes and other sensors of abnormal motion
- forward-facing CCTV
Advantages and Cautions
The primary advantages of Economic Driving assistance applications are to:
- detect uneconomic and unsafe driving
- provide supporting material for mitigation actions, including both retraining and disciplinary measures
- provide the driver with a feedback loop to modify his/her driving style
- contribute to reduction in fuel consumption, emissions, accidents, and vehicle wear and tear
The principal cautions in relation to Economic Driving Assistance are:
- ITS systems can do relatively little to directly control driving style. They are only effective when introduced as part of a more comprehensive program.
- The driver skill and attitude is the primary determinant of fuel efficiency (for a given vehicle and operating condition). ITS support needs to focus on providing feedback and real-time information to assist the driver to adjust and optimise driving style.
Relevant Case Studies
Prince William County