Travel control system for vehicle

1. A travel control system for a vehicle configured to control travel of the vehicle with respect to a congestion section using information about the congestion section acquired from outside of the vehicle, the system comprising: a congestion position estimation unit configured to, when the information about the congestion section cannot be acquired within a prescribed time, estimate a position of the congestion section using a probability distribution model of the congestion section; and a reliability determination unit configured to determine a reliability of the position of the congestion section estimated by the congestion position estimation unit on a basis of a change of the probability distribution model over time.

2. The travel control system for a vehicle according to claim 1 , wherein the information about the congestion section includes at least a position of a tail end of the congestion section and a travel speed at the tail end of the congestion section.

3. The travel control system for a vehicle according to claim 2 , wherein the congestion position estimation unit is configured to estimate the position of the tail end of the congestion section on a basis of the travel speed at the tail end of the congestion section and an elapsed time since the information about the congestion section is last acquired.

4. The travel control system for a vehicle according to claim 1 , wherein the congestion position estimation unit is configured to estimate a position of a tail end of the congestion section premised on that the probability distribution model is a model in which the position of the congestion section follows a normal distribution.

5. The travel control system for a vehicle according to claim 2 , wherein the congestion position estimation unit is configured to estimate the position of the tail end of the congestion section premised on that the probability distribution model is a model in which the position of the congestion section follows a normal distribution.

6. The travel control system for a vehicle according to claim 3 , wherein the congestion position estimation unit is configured to estimate the position of the tail end of the congestion section premised on that the probability distribution model is a model in which the position of the congestion section follows a normal distribution.

7. The travel control system for a vehicle according to claim 4 , wherein the congestion position estimation unit is configured to estimate the position of the tail end of the congestion section to be an end, on a vehicle side, of a predetermined range of the normal distribution.

8. The travel control system for a vehicle according to claim 5 , wherein the congestion position estimation unit is configured to estimate the position of the tail end of the congestion section to be an end, on a vehicle side, of a predetermined range of the normal distribution.

9. The travel control system for a vehicle according to claim 6 , wherein the congestion position estimation unit is configured to estimate the position of the tail end of the congestion section to be an end, on a vehicle side, of a predetermined range of the normal distribution.

10. The travel control system for a vehicle according to claim 1 , wherein the congestion position estimation unit is configured to correct an estimation value of a position of a tail end of the congestion section according to a state of another vehicle traveling around the vehicle.

11. The travel control system for a vehicle according to claim 2 , wherein the congestion position estimation unit is configured to correct an estimation value of the position of the tail end of the congestion section according to a state of another vehicle traveling around the vehicle.

12. The travel control system for a vehicle according to claim 3 , wherein the congestion position estimation unit is configured to correct an estimation value of the position of the tail end of the congestion section according to a state of another vehicle traveling around the vehicle.

13. The travel control system for a vehicle according to claim 1 , wherein when a reliability of a estimation value of a position of a tail end of the congestion section decreases by a predetermined value or more, the reliability determination unit determines that the estimation value of the position of the tail end of the congestion section is not applicable to controlling the travel of the vehicle and stops the control of the travel of the vehicle.

14. The travel control system for a vehicle according to claim 2 , wherein when a reliability of a estimation value of the position of the tail end of the congestion section decreases by a predetermined value or more, the reliability determination unit determines that the estimation value of the position of the tail end of the congestion section is not applicable to controlling the travel of the vehicle and stops the control of the travel of the vehicle.

15. The travel control system for a vehicle according to claim 3 , wherein when a reliability of a estimation value of the position of the tail end of the congestion section decreases by a predetermined value or more, the reliability determination unit determines that the estimation value of the position of the tail end of the congestion section is not applicable to controlling the travel of the vehicle and stops the control of the travel of the vehicle.

16. A travel control system for a vehicle configured to control travel of the vehicle with respect to a congestion section using information about the congestion section acquired from outside of the vehicle, the system comprising circuitry configured to estimate, when the information about the congestion section cannot be acquired within a prescribed time, a position of the congestion section using a probability distribution model of the congestion section; and determine a reliability of the estimated position of the congestion section on a basis of a change of the probability distribution model over time.