ELECTRONIC DASHBOARD DEVICE SUGGESTING THE DRIVING BEHAVIOUR FOR IMPROVEMENT IN FUEL CONSUMPTION

The information to be given to the driver to lower the fuel consumption must be useful in all driving conditions (i.e. at constant speed or acceleration), showing not only the economy level obtained, but also the way to increase it, if possible, by changing the gear ratio, the speed, the acceleration. For this purpose, it is useful to know the way in which power requirement and engine speed determine fuel consumption. A car dashboard device has been prepared showing on the plane having RPM on abscissa and log HP on ordinate the working point of the engine and the level-curves of fuel consumption per hour; this plane is displayed by a led matrix driven by a simple micro-computer. On that plane three fields of different colours characterize three different levels of economy, obtained as a compromise between energetic efficiency of the engine and consumption per hour related to the car speed. The driving behaviour selected as the best (and controlled also by means of road tests) suggests high accelerations at low engine speeds and high gear ratios but avoiding full load. The values of the car speed and the kilometric fuel consumption on a digital display complete the information.