Method and apparatus for traffic-aware speed guidance based on V2X communications

1. A method, comprising: in a traffic environment that includes a followed vehicle and a self-vehicle that acts as a following vehicle,

analyzing, by a processor in a vehicle control apparatus in the self-vehicle, values and change patterns of a plurality of speed inputs to obtain analyzed values, wherein a speed input of the followed vehicle is received through vehicle-to-everything (V2X) communications;

for each analyzed value, calculating by the processor, a respective time to collision (TTC) adjustment, wherein the respective TTC adjustment is computed by a guidance quality analyzer that increases a TTC to lower a speed guidance of the self-vehicle when the self-vehicle speed is decreased relative to a prior speed guidance;

calculating, by the processor, a combined TTC between the self-vehicle and the followed vehicle using the TTC adjustments;

based on the combined TTC, calculating by the processor, a new speed guidance for the self-vehicle; and

providing the new speed guidance to an advanced driving system (ADAS) in the self-vehicle to automatically control the speed of the self-vehicle responsive to the new speed guidance.

2. The method of claim 1 , wherein the plurality of speed inputs includes a speed of the self-vehicle and a speed of a vehicle ahead.

3. The method of claim 2 , wherein the speed of the vehicle ahead is measured by sensors of the self-vehicle.

4. The method of claim 1 , wherein the calculating a respective TTC adjustment includes calculating a driver compliance TTC adjustment.

5. The method of claim 1 , wherein the calculating a respective TTC adjustment includes calculating a road speed fluctuation TTC adjustment.

6. The method of claim 1 , wherein the calculating a respective TTC adjustment includes calculating a vehicle ahead speed TTC adjustment.

7. An apparatus installed in a self-vehicle acting as a following vehicle vs. a followed vehicle, comprising:

a vehicle-to-everything (V2X) communication unit;

a traffic-aware speed guidance unit that includes:

a first analyzer implemented in a processor and configured to analyze stability of road speed on a road and to calculate a road speed fluctuation time to collision (TTC) adjustment using at least one speed input received from the followed vehicle through V2X communications,

a second analyzer implemented in the processor configured to analyze a speed guidance and to calculate a guidance quality TTC adjustment to increase a TTC to lower a speed guidance of the self-vehicle when the self-vehicle speed is decreased relative to a prior speed guidance, and

a third analyzer implemented in the processor configured to analyze a speed of the self-vehicle and a speed of the vehicle ahead and to calculate a vehicle ahead speed TTC adjustment;

a speed guidance combiner unit executed by the processor and configured to calculate a combined TTC between the self-vehicle and the followed vehicle using at least some of the TTC adjustments, and to calculate a new speed guidance of the self-vehicle based on the combined TTC; and

means to provide the new speed guidance to an advanced driving system (ADAS) in the self-vehicle to automatically control the speed of the self-vehicle responsive to the new speed guidance.

8. The apparatus of claim 7 , further comprising a fourth analyzer implemented in the processor and configured to analyze the self-vehicle speed and a target speed and to calculate a driver compliance time-to-collision (TTC) adjustment.

9. The apparatus of claim 8 , further comprising an Adaptive Cruise Control (ACC) unit for providing ACC speed guidance to the speed guidance combiner unit.

10. The apparatus of claim 7 , wherein the at least some of the TTC adjustments used by the speed guidance unit include the road speed fluctuation TTC adjustment.

11. A non-transitory computer-readable medium including instructions executed by a processor in a self-vehicle that acts as a following vehicle to a followed vehicle, to perform a method comprising:

analyzing, by the processor, values and change patterns of a plurality of speed inputs to obtain analyzed values, wherein a speed input of the followed vehicle is received through vehicle-to-everything (V2X) communications;

for each analyzed value, calculating by the processor, a respective time to collision (TTC) adjustment, wherein the respective TTC adjustment includes calculating a guidance quality TTC adjustment to increase a TTC to lower a speed guidance of the self-vehicle when the self-vehicle speed is decreased relative to a prior speed guidance;

calculating, by the processor, a combined TTC between the self-vehicle and the followed vehicle using the TTC adjustments;

based on the combined TTC, calculating, by the processor, a new speed guidance for the self-vehicle; and

providing the new speed guidance to an advanced driving system (ADAS) in the self-vehicle to automatically control the speed of the self-vehicle responsive to the new speed guidance.

12. The non-transitory computer-readable medium of claim 11 , wherein the plurality of speed inputs includes a speed of the self-vehicle and a speed of a vehicle ahead.

13. The non-transitory computer-readable medium of claim 11 , wherein the speed of the vehicle ahead is measured by sensors of the self-vehicle.

14. The non-transitory computer-readable medium of claim 11 , wherein the calculating a respective TTC adjustment includes calculating a driver compliance TTC adjustment.

15. The non-transitory computer-readable medium of claim 11 , wherein the calculating a respective TTC adjustment includes calculating a road speed fluctuation TTC adjustment.

16. The non-transitory computer-readable medium of claim 11 , wherein the calculating a respective TTC adjustment includes calculating a vehicle ahead speed TTC adjustment.