Abstract
Keywords
ADAS, ITS, GPS, optimum velocity, driver interface
Abstract
The alert system developed consists of a real time electronic device for the driver information about the optimum driving velocity, taking into account driving safety criteria. These criteria have been defined considering the geometric characteristics of the road and the dynamic behaviour of the vehicle.
A previous analysis of the road is required. Along this analysis, several road variables have to be calculated, such as: radius, ramp, slope, traffic signals location, way in and way out secondary roads location and their characteristics, lanes number and geometric visibility distance. For carrying out this task, a vehicle with several accurate sensors has been built. This vehicle contains the following on board electronic devices: a no contact velocity sensor, a gyroscopic platform, a video digital camera and a recording system.
The definition of the optimum velocity is based on the geometric parameters of the road, and on a vehicle dynamic model (14 degrees of freedom), for the simulation of the vehicle behaviour on the measured road.
After the definition of the optimum velocity, the problem of the in real time vehicle location has to be solved. For it, a GPS (Global Positioning System) device will be installed in the vehicle. This device, in combination with a digital map and the vehicle speed, calculates the vehicle location with an error less than 5 meters. The digital map is calculated during the project, using the sensor vehicle previously described.
Besides, the algorithm developed for the generation of the driver alert information takes into account the vehicle transverse location in the road lane, specially if the border line is crossed. The lane lines detection is based on the in real time analysis of the images collected by a digital camera. A system based on a FPGA hardware, with an algorithm developed by INSIA, carried out this analysis.
Finally, all the information from the different devices has to be integrated in a platform. The inputs for the system are: the vehicle location (GPS and digital map), the current vehicle velocity, and the lane vehicle transverse location. Considering the optimum driving velocity previously calculated, the system generates an output (acoustic and visual) for alerting to the driver about this optimum velocity. This system has been developed, and a prototype of it is been evaluated with different vehicles and drivers.