than the required deceleration a warning is generated and transmitted to the vehicle that is at risk the process of fig4 steps 4 5 and 6 are repeated for each vehicle identified in the fig3 current data set as vehicles change range velocity and acceleration as a function of time the operation of the fig4 loops and the generation of fig3 data sets will result in real time warnings whenever a vehicle is found to be operating in a potentially hazardous situation for the embodiment cited warnings will be generated within 0 1 sec of the time a hazard arises depending on the magnitude of required deceleration warnings at several levels of urgency can be communicated to transponder equipped vehicles with a time delay that is small compared to the response time of drivers and vehicles warnings to drivers of non transponder equipped vehicles can be communicated via traffic signals and changeable overhead signs in the equation of step 5 the quantity v n is the velocity of the vehicle for which existence of a potential hazard is being computed the quantity v c is the velocity of a potential hazard vehicle or other device the quantity a c is the acceleration of the hazard vehicle or other device the quantity s is a safety.